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Background: This prospective multicenter randomized clinical trial was designed to evaluate the long-term angiographic and clinical outcomes of elective treatment with the GR-II stent compared with the Palmaz-Schatz (PS) stent in patients with coronary stenoses., Methods and Results: Seven hundred fifty-five patients with myocardial ischemia and de novo native coronary stenoses in 3- to 4-mm vessels were randomly assigned to the PS (375 patients) or the GR-II stent (380 patients). The primary end point was 12-month target lesion revascularization (TLR)-free survival. Angiography was performed at baseline and at follow-up in the first 300 consecutive patients to assess the frequency of angiographic restenosis. Procedure success was 98.5% for the GR-II stent and 99.4% for the PS stent (P:=0.19). At 30 days, patients assigned to the GR-II stent had a higher stent thrombosis rate (3.9% versus 0.3% for PS stent, P:<0.001) and TLR rate (3.9% versus 0.5% for PS stent, P:<0.001). The GR-II group had a higher follow-up restenosis frequency (47.3% versus 20.6% for the PS group, P:<0.001) and a lower 12-month TLR-free survival rate (71.7% versus 83.9% for the PS group, P:<0. 001). Multivariate logistic regression analysis identified a smaller final stent minimal lumen diameter (odds ratio [OR] 2.49, 95% CI 1. 56 to 3.98; P:<0.001), diabetes mellitus (OR 2.14, 95% CI 1.42 to 3. 22; P:<0.001), and use of the GR-II stent (OR 1.78, 95% CI 1.20 to 2. 64; P:<0.01) as independent determinants of 12-month TLR., Conclusions: On the basis of these long-term follow-up data, we conclude that use of the GR-II stent should be limited to the acute treatment of abrupt or threatened closure after failed conventional balloon angioplasty procedures.

Background: Ticlopidine has been shown to reduce the incidence of stent thrombosis compared with warfarin, but it may cause serious hematological side effects. Clopidogrel, a new thienopyridine derivative, may be a safe alternative to ticlopidine. The aim of this study was to compare the safety and efficacy of clopidogrel and aspirin with those of ticlopidine and aspirin in patients undergoing coronary stent implantation., Methods and Results: The population of this study consisted of 2 groups: patients who underwent coronary stenting and were treated with ticlopidine and aspirin (TA group, n=1406), and patients who underwent coronary stenting followed by treatment with clopidogrel and aspirin (CA group, n=283). At 1-month follow-up, there was no difference in stent thrombosis (1.5% versus 1.4%, P=1.0) or major adverse cardiac events (3.1% versus 2.4%, P=0. 85) between the TA and CA groups, respectively. The probability of any side effect (neutropenia, diarrhea, rash) was significantly higher in the TA group (10.6% versus 5.3%, P=0.006; relative risk, 0. 53; CI, 0.32 to 0.86)., Conclusions: These data suggest that clopidogrel may be an effective pharmacological regimen after coronary stent implantation. Furthermore, the simpler dosing regimen, the absence of neutropenia, and the lower frequency of other side effects make it a safe alternative to ticlopidine.

Objectives: Our objective was to determine whether a strategy of intended incomplete percutaneous transluminal coronary angioplasty revascularization (IR) compromises long-term patient outcome., Background: Complete angioplasty revascularization (CR) is often not planned nor attempted in patients with multivessel coronary disease, and the extent to which this influences outcome is unclear., Methods: Before randomization, in the Bypass Angioplasty Revascularization Investigation, all angiograms were assessed for intended CR or IR via angioplasty. Outcomes were compared among patients with IR intended if assigned to angioplasty, randomized to coronary artery bypass graft surgery (CABG) versus angioplasty; and within angioplasty patients only, among patients with IR versus CR intended., Results: At 5 years, there was a trend for higher overall (88.6% vs. 84.0%) and cardiac survival (94.5% vs. 92.1%) in CABG versus angioplasty patients with IR intended. The excess mortality in angioplasty patients occurred solely in diabetic subjects; overall and cardiac survival were similar among nondiabetic CABG and angioplasty patients. Freedom from myocardial infarction (MI) at 5 years was higher in nondiabetic CABG versus angioplasty patients (92.4% vs. 85.2%, p = 0.02), vet was similar to the rate observed (85%) in nondiabetic CABG and angioplasty patients with CR intended. Five-year rates of death, cardiac death, repeat revascularization and angina were similar in all angioplasty patients with IR versus CR intended. However, a trend for greater freedom from subsequent CABG was seen in CR patients (70.3% vs. 64.0%, p = 0.08)., Conclusions: Intended incomplete angioplasty revascularization in nondiabetic patients with multivessel disease who are candidates for both angioplasty and CABG does not compromise long-term survival; however, subsequent need for CABG may be increased with this strategy. Whether the risk of long-term MI is also increased remains uncertain.

Background: Conventional balloon angioplasty of very long de novo coronary lesions or very long coronary dissection caused by angioplasty is associated with low success and high complication rates. Multiple intracoronary stents have been used to treat both conditions, although long-term efficacy has not been defined., Methods and Results: Between June 1993 and December 1995, 47 consecutive patients underwent native coronary angioplasty and stenting with 4 or more stents covering at least 2 consecutive diseased coronary segments. Preangioplasty and poststenting diameter stenoses were 81% +/- 13% and 21% +/- 12%, respectively. Reference vessel diameters were 3.53 +/- 0.55 mm proximal to the stents and 2. 95 +/- 0.62 mm distal to the stents. Average lesion length was 63 +/- 20 mm. The number of stents used was 4.5 +/- 1 per vessel (from 4 to 7). Gianturco Roubin I stents were used in all patients. Coronary Palmaz-Schatz stents were used as supplementary stents in 3 patients. Angiographic success was 100%. In-hospital outcomes include 1 death, 1 coronary bypass surgery, no Q-wave myocardial infarction, and 7 non-Q-wave myocardial infarctions. Long-term follow-up at 430 +/- 199 days was completed in all patients. Thirty-five (76%) patients were asymptomatic, 8 (17%) had class 1 or 2 angina, 1 had a myocardial infarction, 13 (28%) underwent repeat angioplasty, 2 patients had subsequent elective bypass surgery, and 3 died during follow-up., Conclusions: Multiple intracoronary stents for very long lesions or dissection can be performed with acceptable immediate and long-term outcomes.

We undertook a study to determine the efficacy of stents in reducing restenosis in cardiac allograft vasculopathy. The result shows that coronary stenting significantly reduces restenosis in cardiac allograft vasculopathy compared with balloon angioplasty alone.

In the general population, peripheral atherosclerosis is a strong predictor of cardiovascular disease and death. In patients with known coronary artery disease, it is unclear whether the presence of additional noncoronary atherosclerosis is of further prognostic value. In the Bypass Angioplasty Revascularization Investigation, 5-year outcome was compared between patients with and without clinically evident noncoronary atherosclerosis. Within the subgroup with noncoronary atherosclerosis, surgery, and angioplasty treatment strategies were compared. Noncoronary atherosclerosis was defined as claudication, peripheral vascular surgery, abdominal aortic aneurysm, history of cerebral ischemia, or carotid disease. Among 1,816 patients, 303 (17%) had noncoronary atherosclerosis. These patients were more likely to have a history of congestive heart failure, diabetes, and hypertension, and were more likely to smoke. Coronary angiographic variables were similar between the 2 groups. Five-year survival was 75.8% for patients with noncoronary atherosclerosis and 90.2% for those without (p < 0.001). The adjusted relative risk of death was 1.7 for any noncoronary atherosclerosis, 1.5 for lower extremity disease alone, 1.7 for cerebral disease alone, and 2.3 for both conditions. Among the 303 patients with noncoronary atherosclerosis, the adjusted relative risk of death for surgery versus angioplasty was 0.87 (p = 0.40). However, the study has limited power to detect a treatment effect in this small subgroup. Thus, patients with combined coronary and clinically evident noncoronary atherosclerosis are a high-risk group with significantly worse long-term outcome compared patients with isolated coronary disease.

Objectives: The purpose of this study was to evaluate the safety, feasibility, optimal deployment technique and 1-year clinical outcome for the Advanced Cardiovascular Systems (ACS) MultiLink stent., Background: Optimal stent deployment assessed by quantitative coronary angiography and intravascular ultrasound (IVUS) is associated with improved clinical outcome., Methods: Forty-nine consecutive patients with a discrete stenosis in a native coronary artery 3 to 4 mm in diameter were treated with the new, balloon-expandable ACS MultiLink stent. Stent expansion was assessed in all patients using quantitative coronary angiography and serial IVUS imaging after 8-, 12- and 16-atm inflations. Clinical follow-up was obtained at 30 days and 1 year., Results: All 49 patients had successful placement of a MultiLink stent without death, emergency coronary artery bypass graft surgery or Q wave myocardial infarction. After placement of the MultiLink stent, the minimal lumen diameter increased from 1.24 to 2.98 mm (p < 0.001), and diameter stenosis decreased from 61% to 7% (p = 0.001). Minimal lumen cross-sectional area by IVUS increased progressively after 8, 12 and 16 atm (5.6 to 6.8 to 7.4 mm2, respectively, p < 0.001). However, only 64% of stents achieved a lumen/reference area ratio > or = 70%. No adverse clinical events occurred by 30 days, and by 1 year only one patient (2.0%) required revascularization of the stented artery., Conclusions: Treatment of stenoses in native coronary arteries with the MultiLink stent is associated with a high success rate and a low incidence of adverse events by 1 year, despite the fact that the majority of stents did not meet IVUS-defined criteria for "optimal stenting" derived from first-generation devices.

In the New Approaches to Coronary Intervention (NACI) registry, 887 patients were electively treated with excimer laser coronary angioplasty (ELCA) for coronary artery disease. The Advanced Interventional System (AIS) system was used in 487 cases; the Spectranetics system, in 400. The mean age was 63.4 years. Most patients had unstable angina (60.3%); 43.7% had a prior myocardial infarction; and 18.6% were high risk or inoperable patients. Mean ejection fraction was 55.4%. A total of 1,000 lesions were treated in the 887 patients. Of the 1,000 lesions treated with ELCA in the 887 patients, 36% were in the right coronary artery; 33%, left anterior descending; 13%, circumflex; 3%, left main; and 16.6%, vein graft. By angiographic core laboratory analysis available for 752 (85%) patients with 839 lesions, lesions were 12.76 mm long. The minimum lumen diameter increased to 1.29 mm after the laser and finally to 1.95 mm after adjunctive percutaneous transluminal coronary angioplasty (PTCA) (which was performed in 93% of all lesions), with a final residual stenosis of 32.1% and Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow in 95%. Dissections of grades B, C, or D were seen after 22.0% of initial laser attempts, and postlaser perforations were noted in 2.6%. Additional such dissections accumulated after adjunctive PTCA but the perforation rate remained low. Procedural success was achieved in 84% of patients, but 1.2% died, 0.7% experienced Q-wave myocardial infarction (MI), and 2.7% required emergency bypass surgery. Multiple logistic regression analysis could not identify any independent predictors of these in-hospital complications. One-year mortality was 5.7% and the cumulative incidence of Q-wave MI was 1.5%. Coronary artery bypass graft (CABG) surgery was performed in 15.0% of patients whereas 25.5% required repeat percutaneous intervention with a target lesion revascularization rate of 31%. Independent predictors of death, Q-wave MI, or target lesion revascularization (which, combined, occurred in 35.6% of patients) were the absence of prior MI, ELCA in the circumflex, perforation after the procedure, and small (<2 mm) final minimal lumen diameter. Considering the large number of patients with high-risk lesions, laser angioplasty was performed with excellent procedural success rates and a reasonable incidence of major complications.

The objective of this study is to compare the in-hospital and follow-up outcome in patients receiving the Gianturco-Roubin stent (GRS) who were enrolled in the New Approaches to Coronary Intervention (NACI) registry. The GRS was approved by the US Food and Drug Administration (FDA) in August 1992 for the treatment of acute or threatened closure after a percutaneous intervention. The application of intracoronary stenting has broadened substantially in the last few years, but less is known about the use of this device for other indications. Since the NACI registry includes patients stented for other indications, a comparison of these groups with patients being stented for acute or threatened closure was undertaken. A GRS was deployed in 497 NACI registry patients. Of these, 466 patients received a GRS in 1 of 3 of the following ways: (1) 351 unplanned stenting after conventional angioplasty of the same lesion; (2) 54 after failed/suboptimal use of a new device in the same lesion; and (3) 61 in planned stenting procedures. This analysis focuses on these 3 patient subgroups and compares their in-hospital outcome and subsequent follow-up to 1 year. There were 520 stented segments in the 466 patients. The group with stenting after failed/suboptimal new-device use had a higher incidence of myocardial infarction (MI) and cardiogenic shock than either the patients with unplanned stenting after percutaneous transluminal coronary angioplasty (PTCA) or planned stenting (MI 22.2% vs 12.0% vs 0%, respectively, and cardiogenic shock 5.6% vs 0.9% vs 0%, respectively; p < 0.05). This group also had significantly lower procedural success (58.7% vs 75.3% vs 81.5%, respectively; p < 0.05). Although not statistically significant, the requirement for transfusion was higher in the unplanned and new-device stented groups than in the planned group (10.5% vs 16.7% vs 1.6%, respectively). Likewise, the incidence of Q-wave MI was higher in the new-device group (22.2% vs 12% vs 0%, respectively; p < 0.05). Despite a higher, in-hospital complication rate in the unplanned groups, follow-up from discharge to 1 year showed similar outcome. In particular, percutaneous reintervention of the stented segment occurred in: 13.0% in the unplanned after new device; 17.4% in the unplanned after PTCA; and 26.2% in the planned group. Although not statistically significant, the higher incidence of percutaneous target lesion revascularization in the planned group probably represents the greater incidence of restenotic lesions in this cohort. In this very heterogeneous group of patients, including those with failure of another new device, the use of the GRS is associated with acceptable in-hospital and follow-up complication rates, although complications were clearly greater when unplanned use of the stent was needed, particularly after failure of another new device. Although the experience is small, patients having the GRS placed in an elective fashion, i.e., the planned group, appear to experience lower in-hospital complication rates, although they have a higher rate of subsequent target lesion revascularization, in this group of predominantly restenotic lesions.

Higher complication rates and lower success rates for treatment of women compared with men have been reported in prior studies of coronary angioplasty and in most early reports of outcome with new coronary interventional devices. In multivariate analysis this has been attributed largely to older age and other unfavorable clinical characteristics. These results are reflected in the current guidelines for coronary angioplasty. Women in prior studies have also had different distributions of vessel and lesion characteristics, but the influence of these differences on the outcome of new-device interventions have not been adequately evaluated. This article evaluates the influence of gender on clinical and angiographic characteristics, interventional procedure and complications, angiographic success, and clinical outcomes at hospital discharge and 1-year follow-up, as observed in the New Approaches to Coronary Intervention (NACI) registry. The NACI registry methodology has been reported in detail elsewhere in this supplement. This study focuses on the 90% of patients-975 women and 1,880 men-who had planned procedures with a single new device and also had angiographic core laboratory readings. Women compared with men were older, had more recent onset of coronary ischemic pain that was more severe and unstable, and had more frequent histories of other adverse clinical conditions. The distributions of several but not all angiographic characteristics before intervention were considered more favorable to angioplasty outcome in women. Differences were observed in device use and procedure staging. Angiographically determined average gain in lumen diameter after new-device intervention, with or without balloon angioplasty, was significantly less in women (1.38 mm) than in men (1.53 mm; p < 0.001); this 0.15 mm difference is consistent with the 0.16-mm smaller reference vessel lumen diameter of women. However, final percent diameter stenoses and TIMI flow and lesion compliance characteristics were similar. Among procedural complications, only treatment for hypotension, blood transfusion, and vascular repair occurred more often in women. More women than men were clinically unstable (2.1% vs 1.1%) or went directly to emergent coronary artery bypass graft surgery (CABG; 1.2% vs 0.6%) on leaving the interventional laboratory. However, in-hospital death (1.4% vs 1.1%), Q-wave myocardial infarction (MI) (0.9% vs 1.1%), and emergent CABG (1.5% vs 1.0%, for women and men, respectively) were not significantly different. Nonemergent CABG was more frequent in women (1.8% vs 0.9%; p < 0.05) and length of hospital stay after device intervention was longer (4.4 days vs 3.8 days in men; p < 0.01). In both univariate and multivariate analyses gender did not emerge as a significant variable in relation to the combined endpoint, death, Q-wave MI, or emergent CABG at hospital discharge. At 1-year follow-up more women than men reported improvement in angina (70% vs 62%) and fewer women than men had had repeat revascularization (32% vs 36%). Similar proportions were alive and free of angina, Q-wave MI and repeat revascularization (46% of women vs 45% of men). Although several procedure-related complications were more frequent in women than men after coronary interventions with new devices, no important disadvantages were observed for women in the rates of major clinical events at hospital discharge and at 1-year clinical follow-up. Additional studies are needed to evaluate the complex interplay of clinical, vessel, and lesion characteristics on success and complications of specific interventional techniques and to determine whether gender, per se, is a risk factor and whether gender specific interventional strategies may be beneficial.

Directional coronary atherectomy (DCA) with the Simpson coronary atherocath seeks to debulk rather than simply displace obstructive tissue and is a means of enlarging the stenotic coronary lumen. This report from the New Approaches to Coronary Intervention (NACI) registry describes the experience of 1,196 patients who underwent DCA as the sole treatment for either native vessel or vein graft lesions. Device success (post-DCA residual stenosis <50% and > or =20% improvement) was achieved in 87.8%, with a lesion success rate (postprocedural residual stenosis <50% and > or =20% improvement) of 94.0%. The mean resultant stenosis after all interventions (by core laboratory) was 19%. Significant in-hospital complications occurred in 2.8% of patients with DCA attempts, including death 0.6%, Q-wave myocardial infarction (MI) 1.5%, and emergent coronary artery bypass graft surgery (CABG) 2.8%. At 1-year follow-up, cumulative mortality was 3.6%, with repeat revascularization in 28% (repeat percutaneous transluminal coronary angioplasty, 20.1%; CABG, 10.6%). This reflected percutaneous or surgical revascularization of the original lesion (target lesion revascularization) in 22.6% of patients. Subgroup analysis showed a lower lesion success rate and an increased complication rate for unplanned use, vein graft treatment, and treatment of a de novo (vs a restenotic) lesion. Multivariate analysis shows that diabetes mellitus, unstable angina, treatment of a restenotic lesion, and greater residual stenosis after the initial procedure were independent predictors of the composite endpoint of death/Q-wave MI/target lesion revascularization by 1-year follow-up. Among these generally favorable acute and 1-year results, the NACI directional atherectomy data confirm the "bigger is better" hypothesis: that lesions with a lower residual stenosis after a successful procedure had significantly fewer target lesion revascularizations between 30 days and 1 year, with no increase in major adverse events.

Angioplasty of aorto-ostial stenosis is associated with lower procedural success and a higher complication rate. The aim of the present study was to compare the acute and long-term results of balloon and new device angioplasty in 110 consecutive patients with right coronary ostial lesions. Patients were divided into 3 groups according to the angioplasty device used: group I (balloon only, n = 26), group II (debulking devices including excimer laser, directional and rotational atherectomy, n = 26), group III (stent, n = 58). Procedural success was highest in group III (96%) followed by group I (88%), and group II (77%). In-hospital complications were similar among the groups (p = NS). Patients in group III achieved the highest acute gain (2.61 mm) followed by groups II (1.92 mm), and I (1.39 mm, p <0.05). During follow up, target lesion revascularization and/or bypass surgery was required in 24% of patients in group III compared with 47% and 40% in groups I and II, respectively (p <0.05). Cardiac-event free survival was highest in the stent group (74%, p <0.005) and was similar between the balloon (39%) and debulking device groups (45%). Thus, among the currently available technologies, stenting of right coronary ostial lesions appears to provide excellent angiographic and long-term results.

Objectives: We sought to determine the in-hospital clinical outcome and angiographic results of patients prospectively entered into the National Heart, Lung, and Blood Institute/New Approaches to Coronary Intervention (NHLBI/NACI) Registry who received Gianturco-Roubin stents as an unplanned new device., Background: Between August 1990 and March 1994, nine centers implanted Gianturco-Roubin flex stents as an unplanned new device in the initial treatment of 350 patients (389 lesions) who were prospectively enrolled in the NHLBI/NACI Registry., Methods: Patients undergoing implantation of the Gianturco-Roubin flex stent were prospectively entered into the Gianturco-Roubin stent portion of the NHLBI/NACI Registry. Only subjects receiving the Gianturco-Roubin stent as a new device in an unplanned fashion are included., Results: The mean age of the patient group was 61.8 years, and the majority of the patients were men. A history of percutaneous transluminal coronary angioplasty (PTCA) was present in 35.4% of the group, and 16.9% had previous coronary artery bypass graft surgery. Unstable angina was present in 67.7%. Double- or triple-vessel coronary artery disease was present in 55.4%, and the average ejection fraction was 58%. The presence of thrombus was noted in 7.3%, and 7.2% had moderate to severe tortuosity of the lesion. The angiographic success rate was 92%. Individual clinical sites reported that 66.3% of the stents were placed after suboptimal PTCA, 20.3% for abrupt closure and 13.4% for some other technical PTCA failure. Major in-hospital events occurred in 9.7% of patients, including death in 1.7%, Q wave myocardial infarction in 3.1% and emergency bypass surgery in 6%. Abrupt closure of a stented segment occurred in 3.1% of patients at a mean of 3.9 days. Cerebrovascular accident occurred in 0.3%, and transfusion was required in 10.6%. Vascular events with surgical repair occurred in 8.6% of patients., Conclusions: Despite these complications, the use of this device for the treatment of a failed or suboptimal PTCA result remains promising given the adverse outcome of abrupt closure with conventional (nonstent) treatment.

We describe a patient who underwent stenting of both internal carotid arteries and two coronary arteries. Two combined carotid and coronary procedures were done 4 wk apart to revascularize the patient. The first procedure was complicated by a minor stroke with good recovery. At 6 mo of follow-up, he is asymptomatic and without angiographic restenosis.

Since the first description of percutaneous transluminal coronary angioplasty (PTCA), the number of patients who have undergone this procedure has rapidly increased. Two problems have plagued PTCA: acute vessel closure and restenosis. Acute vessel closure following PTCA increases the incidence of in-hospital death, myocardial infarction and coronary bypass grafting. The advent of intracoronary stenting for acute closure has had a profound impact on these complications. Complications following intracoronary stenting have declined with modification of anticoagulation post-stenting and an improved understanding of stent mechanics. Further refinement of these devices and continued improvement in our understanding of them should lead to further reduction of post-stent complications and improved patient outcomes.

This prospective nonrandomized study was performed comparing aspirin alone (n = 46) versus aspirin and ticlopidine (p = 338) following native coronary artery stenting. There were significantly more stent thrombosis events in the aspirin-only group than in the aspirin and ticlopidine group (6.5% vs 0.9%, p = 0.02) and significantly more Q-wave myocardial infarctions and cardiac-related deaths in the aspirin-only group than in the aspirin and ticlopidine group (6.5% vs 0%, p = 0.002 and 4.4% vs 0.3% p = 0.02, respectively).

Two patients with restenosis following implantation of the Gianturco-Roubin stent were successfully treated with the transluminal extraction atherectomy device, with the assistance of intravascular ultrasound guidance and adjunctive balloon angioplasty. The optimal management strategy of in-stent restenosis remains unclear, but the transluminal extraction atherectomy device may be an option for the management of restenosis within the Gianturco-Roubin stent.

Background: Although several studies have established that the complications of percutaneous transluminal coronary angioplasty (PTCA) are related to clinical and angiographic variables such as advanced age and lesion complexity, it is uncertain whether the use of hospital resources after PTCA also depends on the same baseline variables. The purpose of this study was to identify the factors responsible for prolonged hospital stay after PTCA., Methods and Results: The study cohort included 591 consecutive patients undergoing conventional balloon angioplasty at nine medical centers in North America. Major or minor complications occurred in 91 patients (15.4%) and were observed to be related to several baseline characteristics, including unstable angina, multivessel coronary artery disease, patient age, and lesion complexity. Compared with a median length of hospital stay of 2.0 days after PTCA (25th, 75th percentiles: 2.0, 4.0) for the entire cohort of patients, the length of stay was increased in patients with unstable angina (3.0 days [2.0, 5.0]; P = .002), multivessel coronary artery disease (3.0 [2.0, 5.5]; P = .001), age > 65 years (3.0 [2.0, 5.5]; P = .02), complex lesions (3.0 [2.0, 6.0]; P = .001), and filling defects (6.0 [2.0, 11.0]; P < .001). The length of stay was more strikingly increased, however, in patients who experienced major or minor PTCA complications, such as emergency bypass surgery (9.0 days [8.0, 18.0]; P < .001), Q-wave or non-Q-wave myocardial infarction (8.0 [6.0, 15.5]; P < .001), transfusion unrelated to bypass surgery (8.0 [4.0, 12.0]; P < .001), or abrupt vessel closure (6.0 [3.0, 10.5]; P < .001). On stepwise multiple linear regression, PTCA complications appeared to be the strongest predictors of length of hospital stay (all P < .001) and overwhelmed the weaker relation between length of stay and several individual baseline variables. Inclusion of a composite clinical risk score (reflecting the presence of unstable angina, multivessel disease, advanced age, complex lesions, or filling defects) in the regression model confirmed that patients with several high-risk baseline variables had a significant increase in length of stay after PTCA (P = .003), but PTCA complications remained the strongest predictors of length of stay., Conclusions: Although PTCA complications were correlated with baseline variables such as unstable angina, multivessel disease, advanced age, complex lesions, and filling defects, excess length of stay after PTCA was most strongly influenced by the development of minor and major PTCA complications. Because patients with several baseline risk factors experienced significantly prolonged hospitalizations, improved selection of patients may contribute to reductions in length of stay after PTCA. A greater reduction in resource use after PTCA, however, would be expected from developing new treatments to decrease PTCA complications rather than limiting the access of patients with unstable angina, advanced age, or complex lesions to PTCA.

This study was carried out to stratify the risk of stent thrombosis by using three predictors: stent size, poststenting residual dissection, and residual filling defect. In the multicenter clinical trial, 1318 patients had successful deployment of Gianturco-Roubin coronary stent for threatened and acute closure. The 714 (54.2%) patients having none of these risk factors were designated a low-risk group; 484 (36.6%) had one factor and were designated an intermediate-risk group; 120 (9.1%) had two or all three factors and were designated a high-risk group. The incidence of stent thrombosis was 5.6%, 9.4%, and 16.7% in the low-, intermediate-, and high-risk groups; the difference among the three groups was highly significant (p < 0.0001). With these three predictors, the risk of stent thrombosis can be stratified. Avoiding the use of small stents (< 3.0 mm) and achieving optimal angiographic results after stenting for acute or threatened closure are useful strategies in reducing stent thrombosis.

Percutaneous transluminal coronary angioplasty (PTCA) is currently performed in many patients seeking care because of severe manifestations of multivessel coronary artery disease. Previously, the majority of such patients would have undergone coronary artery bypass grafting (CABG). No definitive evidence is available as to which initial revascularization strategy has the best long-term clinical and economic outcomes. The Bypass Angioplasty Revascularization Investigation (BARI) is the largest of several recent clinical trials that were designed to test the hypothesis that an initial strategy of PTCA in selected patients with multivessel coronary artery disease does not compromise long-term clinical outcome compared with an initial strategy of CABG. This report describes how patients were screened, selected, and recruited in BARI and how this process may influence the results and the interpretation of the trial. During the enrollment period, 25,200 patients undergoing diagnostic coronary angiography at the participating institutions or with off-site angiograms referred to BARI investigators were screened for BARI eligibility. Excluded from screening were patients without coronary artery disease, those with single-vessel disease, prior revascularization, primary congenital, valvular, or myocardial disease, and age > 80 years. Slightly more than half of the patients screened (12,670) were not clinically eligible for BARI because of left main disease, insufficient symptoms, emergency revascularization, or other logistic reasons. Thus, 12,530 patients had severe angina and/or ischemia and were clinically eligible for BARI. Nearly 33% of them (4,110) had multivessel disease, which was suitable for both PTCA and CABG.(ABSTRACT TRUNCATED AT 250 WORDS)

Background: Early loss of minimal luminal diameter (MLD) after successful percutaneous transluminal coronary angioplasty (PTCA) is associated with a higher incidence of late restenosis., Methods and Results: Sixty-six patients (66 lesions) with > 0.3 mm MLD loss at 24-hour on-line quantitative coronary angiography were randomized into two groups: 1, Gianturco-Roubin stent (n = 33) and 2, Control, who received medical therapy only (n = 33). All lesions were suitable for stenting. Baseline demographic, clinical, and angiographic characteristics were similar in the two groups. Restenosis (> or = 50% stenosis) for the overall group occurred in 32 of 66 patients (48.4%) at 3.6 +/- 1-month follow-up angiography. Restenosis was significantly greater in group 2 than in group 1 (75.7% versus 21.2%, P < .001). Vascular complications (21.2% versus 0%) and length of hospital stay (7.3 +/- 1 versus 2.4 +/- 0.5 days, P < .01) were higher for the stent group. Although at follow-up there were no differences in mortality or incidence of acute myocardial infarction between the two groups, patients in the control group had a higher incidence of repeat revascularization procedures (73% versus 21%, P < .001)., Conclusions: In patients with successful PTCA but reduced luminal diameter demonstrated by repeat angiography at 24 hours, the Gianturco-Roubin stent appears to reduce angiographic restenosis at follow-up.

Background: Although the development of thrombus or dissection during percutaneous transluminal coronary angioplasty (PTCA) increases the risk of abrupt vessel closure, the magnitude of the effect is difficult to define., Objective: The aim of the study was to determine prospectively the effect of the development of thrombus or dissection on PTCA procedural outcome., Methods: Data from 591 consecutive angioplasty procedures involving 756 lesions at 9 clinical centers were included in a prospective registry with a core angiographic laboratory., Results: Clinical success (defined as < 50% stenosis of all target lesions assessed in a core angiographic laboratory, with no major complications of death, Q wave or non-Q wave myocardial infarction or emergency CABG) was achieved in 497 patients (84%). Major complications occurred in 45 (7.6%). Abrupt vessel closure, including both established closure (TIMI grade 0 or I flow) and impending closure (> 50% stenosis, TIMI grade 0-2 flow, plus use of additional interventions) occurred in 65 patients (11%). Angiographically visible dissections developed in 40% of lesions; more severe grades of dissection were associated with reduced success rates, and increased incidence of and abrupt vessel closure and major complication. Angiographic evidence of thrombus (filling defects) developed in 12.3% of lesions; the presence of thrombus was associated with significantly lower procedural success (61% vs. 86%) and significantly higher rates of abrupt vessel closure (28% vs 7%) and major complications (24% vs. 6%). With multivariable analysis, thrombus was identified as an independent predictor of procedural success, abrupt vessel closure, and major complications., Conclusions: The development of severe dissections or thrombus following PTCA is associated with significantly lower procedural success rates and higher rates of abrupt vessel closure and major complications. Patients who develop severe dissection or thrombus may be appropriate candidates for more aggressive forms of therapy.

A small residual stenosis and a low residual translesional pressure gradient after percutaneous transluminal coronary angioplasty (PTCA) are thought to be associated with lower rates of restenosis. However, these two posprocedure parameters have not been studied simultaneously in relation to late angiographic outcome. Restudy angiograms after successful single-vessel and single-lesion PTCA were performed in 1261 patients, who were divided into three groups according to final residual stenosis: group 1, 0% to 19%, group 2, 20% to 34%, and group 3, 35% to 49%. This study population also was divided into two groups by final residual pressure gradient: < or = 17 and > or = 18 mm Hg. Luminal patency at restudy and restenosis rates by these definitions were studied. By the definition of > or = 50% stenosis at restudy, group 1 had the lowest restenosis rate, and group 3 had the highest. By the definition of an increase of > or = 30% stenosis compared with the immediate post-PTCA result, group 1 had the highest restenosis rate, and group 3 had the lowest. Although it had the greatest loss of luminal diameter over the follow-up period, group 1 maintained the greatest luminal patency at restudy. A residual pressure gradient < or = 17 mm Hg was associated with lower restenosis rate regardless of the definition used. Despite greater loss of luminal diameter over the follow-up period, optimal postprocedure angiographic results may result in better long-term luminal patency. Transluminal pressure gradient is more predictive of late angiographic results regardless of the definition used. Further studies, with hemodynamic measurements, may reveal potential clinical implications.

Sixty patients with 1 or 2 stainless steel intracoronary stents (Cook, Inc.) underwent balloon angioplasty for in-stent restenosis 1.5-13.5 months after stenting. Seventy-five in-stent redilatation procedures were performed. Seventy-three restenotic lesions (97%) were successfully recrossed and dilated, reducing the mean pre-angioplasty intrastent diameter stenosis from 77 +/- 12% to 20 +/- 11% residual. Although one angioplasty (1.3%) was complicated by non-Q-wave infarction, no angioplasty-related death, acute closure, need for additional stenting, emergent coronary bypass surgery, side branch occlusion, or vascular sequelae occurred. Post-procedure heparin was not used in 83% of successful cases. Most patients were discharged the day following redilatation (mean in-hospital stay 1.7 +/- 1.3 days). At 5.4 +/- 3.4 months following in-stent angioplasty, 84% of patients were in Canadian Cardiovascular Society class 0 or I. In conclusion, balloon dilatation in this stent for restenosis appears simple and efficacious in the short term, and may entail less risk than dilatation of unprotected coronary vessels.

Historically, long coronary artery stenoses undergoing percutaneous transluminal coronary angioplasty (PTCA) are reported to have reduced procedural and clinical success in comparison with shorter lesions. The efficacy of long balloons (30 or 40 mm) in long lesions was evaluated. Eighty-two patients had 84 PTCA procedures with a primary long balloon. In all, 86 lesions were available for analysis. Data were collected prospectively on standard PTCA procedure forms. Coronary angiograms were reviewed and measured with digital calipers. Hospital charts were examined for complications. PTCA was performed in the left anterior descending artery in 44 cases (51%), the right coronary artery in 29 (34%) and the circumflex artery in 13 (15%). With the use of a modified classification system, 47 lesions (55%) were class C, 24 (28%) were class B2 and 15 (17%) were class B1. Mean lesion length was 22 +/- 11 mm (range 10 to 72), and 38 lesions (44%) were > or = 20 mm. Twelve patients received an intracoronary stent. The long balloon alone produced angiographic success (< 50% residual stenosis) in 77 lesions (90%). Angiographic success was achieved ultimately in all stenoses, using a stent in 7 patients and a short balloon in 2. There were 2 deaths (2%) and 1 Q-wave myocardial infarction (1%). One patient needed coronary artery bypass surgery. Clinical success without death, Q-wave infarction or bypass surgery was achieved in 83 of 86 procedures (97%). In conclusion, the use of long PTCA balloons with adjuvant stenting produced excellent results in these long stenoses. Lesion length was not a precursor of poor angiographic or clinical outcome.

Background: Abrupt vessel closure and early reocclusion remain the principal vascular events underlying early recurrent ischemia complicating elective percutaneous transluminal coronary angioplasty (PTCA). Intracoronary stenting has been used to circumvent emergency bypass surgery after acute vessel closure and as an adjunct for the elective treatment of restenosis. The initial multicenter experience with the Gianturco-Roubin stent is presented, and predictors for early recurrent ischemic events are identified., Methods and Results: Data accrued from 639 serial patients undergoing emergency stenting for abrupt closure (n = 415; 65%) or elective deployment for restenosis (n = 224; 35%) from October 1989 through May 1991 were analyzed. The incidence of subsequent ischemic events, including death, nonfatal myocardial infarction, and bypass surgery referral within 90 days of the procedure, was higher after acute deployment (20%) compared with elective stenting (9%; P = .0004). Although mortality within the two cohorts was the same (3%; P = NS), there were significant differences in the incidence of nonfatal myocardial infarction (5% versus 0.5%; P = .002) and bypass surgery (12% versus 6%; P = .02) between the acutely and electively stented patients, respectively. These events were significantly more common when the stent was undersized to the target vessel diameter (stent:artery ratio for event, 0.95 +/- 0.14 versus no event, 1.04 +/- 0.22; P = .0001) or when there was less expansion of the lesion by the deployed device (stent-to-lesion diameter ratio for event, 6.6 +/- 9.2 versus no event, 11.0 +/- 21.4; P = .0001). In a stepwise logistic regression model, acute stenting (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.3 to 2.4), multivessel disease (OR, 1.4; CI, 1.1 to 1.8), larger target lesion diameter (OR, 2.1; CI, 1.4 to 3.2), larger target vessel (OR, 2.9; CI, 1.7 to 4.7), and smaller stent size (OR, 6.1; CI, 3.0 to 12.3) were independent predictors of early, recurrent ischemic events. The presence of thrombus was associated with a higher event rate after elective stenting (OR, 2.3; CI, 1.06 to 5.4) but was not associated with a higher early event rate after acute stenting., Conclusions: Early ischemic events are more common after acute stenting for abrupt or threatened closure than after elective deployment. These events may be avoided with careful attention to morphometric characteristics to avoid undersizing the stent to the target vessel and ensure adequate lesion expansion.

Background: To be used optimally, new interventional devices (stent, lasers, atherectomy catheters) must be carefully evaluated in terms of optimal patient and lesion selection, technique of use, expected acute success and complications, and long-term results. Sources for that information include single-center and multicenter (single-device) reports, although randomized trials may then be performed to provide a more definitive picture of any clinical benefits. One interim option, however, consists of carefully collected registry data. The purpose of this article is to review data collected in the National Heart, Lung, and Blood Institute-funded New Approaches to Coronary Intervention (NACI) Registry and to compare them with existing reports., Methods and Results: NACI is an independent, investigator-driven effort that seeks to collect uniform data on patients undergoing treatment with one of several investigational devices and thereby provide an unbiased report of procedure outcome. Between November 1990 and November 1992, 36 participating centers treated a total of 3201 lesions in 2835 patients, using one of seven study devices: directional atherectomy (1084 lesions), transluminal extraction atherectomy (240 lesions), rotational atherectomy (349 lesions), Palmaz-Schatz stent (674 lesions), Gianturco-Roubin stent (213 lesions), and the Advanced Interventional Systems (474 lesions) or Spectranetics (167 lesions) excimer lasers. Data on each procedure were recorded on a unique modular database that captured the reason for (and interim result after) each device use. Device success (defined here as stenosis improvement by > or = 20% and a residual stenosis < 50% after new device use) was 66.5% overall. Adjunctive angioplasty was used in 75.5% of lesions, either before (25.9%) or after (43.5%) new device use, yielding an overall lesion success (> or = 20% stenosis improvement with a final residual stenosis < 50% after all devices) of 92.2%. Adjunctive angioplasty after new device use produced further enlargement in minimal lumen diameter (from 2.2 to 2.7 mm) and further reduction in residual stenosis (26.4% to 16.1%) compared with the results present after use of the new devices themselves. Major complications consisting of death (1.6%), Q-wave myocardial infarction (1.3%), or emergency bypass surgery (1.7%) occurred in 4.0% of patients (range, 2.6% to 8.7% across devices). Procedural success, defined as lesion success in all new device-treated lesions without a major complication, was achieved in 90.8% of patients, with a median length of hospital stay of 4 days., Conclusions: NACI illustrates the type of information that can be obtained in a registry format that examines the acute angiographic and clinical results of new devices according to uniform definitions. Although no registry can substitute for formal interdevice trials, registries such as this can supplement earlier single-center and multicenter reports. In doing so, they can help focus subsequent randomized interdevice comparisons on lesion types for which two or more devices have promising acute results. Given the substantial interdevice differences in baseline patient and lesion characteristics found in NACI, simple "head-to-head" comparison of the results of different devices might give misleading impressions and should be avoided unless such comparisons are restricted to carefully matched patient and lesion subgroups.

Objectives: This study reports on the initial experience with the Gianturco-Roubin flexible coronary stent. The immediate and 6-month efficacy of the device and the incidence of the complications of death, myocardial infarction, emergency coronary artery bypass surgery and recurrent ischemic events are presented., Background: Abrupt or threatened vessel closure after coronary angioplasty is associated with increased risk of myocardial infarction, emergency coronary artery bypass graft surgery and in-hospital death. When dissection or prolapse of dilated plaque into the lumen is unresponsive to additional or prolonged balloon catheter inflation, coronary stenting offers a nonsurgical mechanical means to rapidly restore stable vessel geometry and adequate coronary blood flow., Methods: From September 1988 through June 1991, 518 patients underwent attempted coronary stenting with the 20-mm long Gianturco-Roubin coronary stent for acute or threatened vessel closure after angioplasty. In 494 patients, one or more stents were deployed. Thirty-two percent of patients received stents for acute closure and 69% for threatened closure., Results: Successful deployment was achieved in 95.4% of patients. Overall, stenting resulted in an immediate angiographic improvement in the diameter stenosis from 63 +/- 25% before stenting to 15 +/- 14% after stenting. Emergency coronary artery bypass graft surgery was required in 4.3% (21 of 493 patients). The incidence of in-hospital myocardial infarction (Q wave and non-Q wave) was 5.5% (27 of 493 patients). At 6 months, myocardial infarction was infrequent, occurring in 1.6% (8 of 493 patients). The incidence of in-hospital death was 2.2% (11 of 493 patients). Late death occurred in 7 patients (1.4%) and 34 patients (6.9%) required later bypass graft surgery. Complications included blood loss, primarily from the arterial access site, and subacute thrombosis of the stented vessel in 43 patients (8.7%)., Conclusions: The early multicenter experience suggests that this stent is a useful adjunct to coronary angioplasty to prevent or minimize complications associated with flow-limiting coronary artery dissections previously correctable only by surgery. Although this study was not randomized, it demonstrated a high technical success rate and encouraging results with respect to the low incidence of emergency coronary artery bypass graft surgery and myocardial infarction.

This report describes a patient with a chronically occluded proximal LAD in whom antegrade flow was not re-established by successful dilatation alone. Obliteration of retrograde collateral flow restored antegrade flow. This case demonstrates the potential detrimental effect of vigorous collateral flow on the patency of chronic occlusions after successful PTCA.

Serum lipoprotein (a) (Lp[a]) has been associated with coronary artery atherosclerosis. Its association with restenosis after percutaneous transluminal coronary angioplasty (PTCA) has not been previously studied. Serum levels of Lp(a), in addition to other lipoproteins, and their components using standard assays, were determined in subjects undergoing cardiac catheterization within 10 months after PTCA. Clinical (e.g., sex, diabetes, angina class) and angiographic (e.g., PTCA percent diameter reduction) factors were not different between the group without (diameter reduction less than 50%; group A) and the group with (diameter reduction greater than or equal to 50%; Group B) restenosis. Total cholesterol, triglycerides, high- and low-density lipoprotein cholesterol, apolipoprotein A-I, apolipoprotein B and Lp(a) were compared. Univariate predictors of restenosis were serum triglycerides (2.50 +/- 1.07 mmol/liter for group A vs 1.72 +/- 0.79 +/- mmol/litre for group B, p = 0.008), and Lp(a) (median: 7.0 mg/dl [range 0 to 44] for group A vs 19 mg/dl [range 1 to 120] for group B; p = 0.006). Stepwise logistic regression revealed the only significant independent predictor of restenosis to be serum Lp(a) (p = 0.018). Each quintile of Lp(a) was associated with a progressively higher risk of restenosis, with the highest quintile (40 to 120 mg/dl) having an odds ratio of 11 (95% confidence interval 9 to 13) compared with the lowest quintile (0 to 3.9 mg/dl) (p = 0.033). A serum Lp(a) of greater than 19 mg/dl was associated with an odds ratio of 5.9 (95% confidence interval 4.6 to 7.2) (restenosis rates of 58% in the group with 0 to 19 mg/dl and 89% in the group with 19 to 120 mg/dl; p = 0.006).(ABSTRACT TRUNCATED AT 250 WORDS)

BACKGROUND. Acute closure remains a significant limitation of percutaneous transluminal coronary angioplasty (PTCA) and underlies the majority of ischemic complications. This study details the clinical and angiographic characteristics of a series of patients receiving an intracoronary stent device to manage acute and threatened closure and presents the early clinical results. METHODS AND RESULTS. From October 1989 through June 1991, 115 patients undergoing PTCA received intracoronary stents to treat acute or threatened closure in 119 vessels. Sixty-three percent had multivessel coronary disease, 33 (29%) had undergone prior coronary artery bypass grafting (CABG), and 52 (45%) had had previous PTCA. Using the American College of Cardiology/American Heart Association (ACC/AHA) classification, 15% of lesions were class A, 55% were class B, and 30% were class C. Eight patients were referred with severe coronary dissection and unstable angina after PTCA at other institutions. Acute closure was defined as occlusion of the vessel with TIMI (Thrombolysis in Myocardial Infarction) 0 or 1 flow immediately before stent placement. Threatened closure required two or more of the following criteria: 1) a residual stenosis greater than 50%, 2) TIMI grade 2 flow, 3) angiographic dissection comprising extraluminal dye extravasation and/or a length of greater than 15 mm, 4) evidence of clinical ischemia (either typical angina or ECG changes). Twelve vessels (10%) met the criteria for acute closure, and 87 vessels (73%) satisfied the criteria for threatened closure. Twenty vessels (17%) failed to meet two criteria. Stenting produced optimal angiographic results in 111 vessels (93%), with mean diameter stenosis (+/- 1 SD) reduced from 83 +/- 12% before to 18 +/- 29% after stenting. Overall, in-hospital mortality was 1.7% and CABG was required in 4.2%; Q wave myocardial infarction (MI) occurred in 7% and non-Q wave MI in 9%. Stent thrombosis occurred in nine patients (7.6%). For the 108 patients who presented to the catheterization laboratory without evolving MI, Q wave MI occurred in 4% and non-Q wave MI occurred in 7%. Angiographic follow-up has been performed in 81 eligible patients (76%), and 34 patients (41%) had a lesion of greater than or equal to 50%. CONCLUSIONS. This stent may be a useful adjunct to balloon dilatation in acute or threatened closure. Randomized studies comparing this stent with alternative technologies are required.

To test whether alpha-tocopherol prevents restenosis following percutaneous transluminal coronary angioplasty (PTCA), we enrolled patients in a double-blind, placebo-controlled trial. Patients were randomized after successful PTCA to receive vitamin E in the form of dl-alpha-tocopherol, 1200 IU/day, orally vs an inactive placebo for 4 months. Patients' blood was analyzed at baseline and at 4 months post-PTCA for differences in plasma lipids, lipoproteins, apolipoproteins, alpha-tocopherol, retinol, beta-carotene and lipoperoxide concentrations. One hundred patients completed the protocol. No significant difference was found in any parameter except alpha-tocopherol level between the vitamin E group and the placebo group, verifying compliance. Follow-up cardiac catheterization was obtained in 83% of the patients receiving placebo and in 86% of the patients receiving dl-alpha-tocopherol. Including thallium and exercise stress testing, objective information was obtained for practically all the patients receiving dl-alpha-tocopherol or placebo. Restenosis was defined as the presence of a lesion with greater than or equal to 50% stenosis in a previously dilated artery segment and results were analyzed with respect to pre- and post-PTCA artery diameter, vessel diameter at follow-up, and restenosis rate. Patients receiving dl-alpha-tocopherol had a 35.5% restenosis angiographically documented vs 47.5% restenosis in patients receiving the placebo. The overall incidence of restenosis defined by an abnormal angiogram or thallium test or exercise stress test was 34.6% in patients receiving dl-alpha-tocopherol and 50% in patients receiving the placebo. This difference (p = 0.06) did not reach significance because of an inadequate sample size.

To better understand the factors predisposing a patient to death after elective percutaneous transluminal coronary angioplasty (PTCA) and to gain insight into indications for high-risk PTCA both with and without adjunctive use of support devices, the outcomes of 8,052 consecutive procedures were reviewed. Death occurred after 32 procedures (0.4%) and was directly related to coronary artery closure in 26 (81%) of these cases. Left ventricular failure due to vessel closure at the dilated site, the most common cause of death, was independently correlated with female sex (p less than 0.001), "jeopardy score" (p less than 0.001) and PTCA of a proximal right coronary artery site (p = 0.002), but not with left ventricular ejection fraction or presence of multivessel disease. Right ventricular failure after closure of the proximal right coronary artery, and left main coronary dissection accounted for the majority of the remaining deaths. Systolic blood pressure immediately after coronary artery closure was also closely correlated with jeopardy score, and cardiogenic shock was frequent in women with scores greater than or equal to 3.5 and in men with scores greater than or equal to 5.0. These data highlight the superiority of the jeopardy score versus ejection fraction in the determination of risk, stress the importance of gender in determining outcome and point to the need for better means of right ventricular protection from severe ischemia. Therefore, an initial framework for rational use of PTCA and support devices in the high-risk setting is established.

After percutaneous transluminal coronary angioplasty, 3 to 7% of patients have in-hospital coronary closure, and the risk of subsequent myocardial infarction is high, even with an urgent bypass operation. Disrupted coronary morphologic integrity, particularly with large dissections, may be associated with an increased risk of acute coronary closure. A percutaneously placed coronary vascular stent may rapidly alleviate acute or threatened coronary closure and could reduce morbidity. Between October 1989 and June 1990, placement of a balloon-expandable, flexible metallic coil (Gianturco-Roubin) coronary stent was attempted 16 times in 15 Mayo Clinic patients--for treatment of actual or threatened abrupt coronary closure in 10 patients, for primary treatment of a lesion judged to be at high risk for dissection with conventional balloon angioplasty in 1, and for elective treatment of restenotic lesions in 5. Placement of the stent was successful in 15 attempts (94%). Associated complications, which were uncommon, were similar to those noted after balloon angioplasty. No early deaths occurred, and no patient required coronary artery bypass grafting. Stents were successfully placed in both urgent and elective circumstances in native coronary arteries and saphenous vein grafts, and they were used in primary atheromatous and restenotic lesions. Our initial experience with this metallic coil stent indicates that it is efficacious for vascular disruption that is threatening or causing coronary closure after angioplasty. Furthermore, elective placement of a stent may be safely undertaken in patients with high-risk coronary lesions or recurrent restenotic lesions. The long-term outcome in all groups of patients who receive coronary stents is unknown.

To determine the relation among lipids in predicting coronary artery disease (CAD), 213 patients undergoing diagnostic angiography for suspected CAD were prospectively studied. Twenty-one patients had normal coronary arteries and 192 had CAD in 1 to 3 arteries at arteriography with measurements obtained with digital calipers. Lipoproteins were measured and lipoprotein (a) [Lp(a)] was also assayed in a subset of 98 patients with CAD. Statistical analysis was performed using uni- and multivariate techniques to test the association among age, gender, systemic hypertension, diabetes mellitus, cigarette smoking, family history, total cholesterol, triglycerides, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, very low density lipoprotein cholesterol, apolipoproteins (apo) A-I and apo B, ratio of apo A-I to apo B, and ratio of HDL cholesterol to total cholesterol, to Lp(a) and to CAD. All factors except gender, systemic hypertension, diabetes mellitus and cigarette smoking were univariate predictors of CAD. Multivariate predictors were, in decreasing order of significance, family history, age, HDL/total cholesterol ratio and apo B. When Lp(a) was included, multivariate predictors were age, family history, apo B and Lp(a), in that order. Lipid parameters alone showed that the HDL/total cholesterol ratio and that Lp(a) provide the best predictive tests for the detection of CAD in this referral population and may ultimately become important screening tests for CAD.

Of 6,545 patients who had elective coronary angioplasty procedures performed over a 7.5-year period from June 1980 through December 1987, 114 (1.7%) never had symptoms of myocardial ischemia. Exercise-induced silent myocardial ischemia was documented before angioplasty in 94% of these asymptomatic patients. Angioplasty was successful in 87%, whereas emergency coronary artery bypass grafting was required in 4%, and a further 2% had myocardial infarctions after the procedures. The remaining 7% had unsuccessful angioplasty procedures but experienced no in-hospital cardiac events. The follow-up period after hospital discharge averaged 43 +/- 20 months (range 5 to 93). There were no deaths. In the group of 99 patients with initially successful angioplasty procedures the follow-up interval ranged from 5 to 92 months. During that period, 7 patients underwent coronary bypass surgery, 4 patients had myocardial infarction and 30 patients had repeat angioplasty procedures for restenosis. The cumulative probability of event-free survival over 5 years for the group with successful angioplasty was: 100% freedom from death, 95% freedom from myocardial infarction, 87% freedom from myocardial infarction or coronary bypass surgery and 61% freedom from myocardial infarction, coronary bypass surgery or repeat angioplasty. Thus, coronary angioplasty performed in 114 asymptomatic patients, most with exercise-induced silent myocardial ischemia, achieved very good primary success and was accompanied by low cardiac event rates and no deaths over several years of patient follow-up.

Intimal tear or dissection is an important descriptor of ischemic complications after coronary angioplasty, but only the minority of patients will develop an acute ischemic event. To identify additional factors that may predict the development of an ischemic event when arterial disruption occurs during otherwise uncomplicated angioplasty, the records of 1,346 patients prospectively identified as having tear or dissection without immediate vessel closure were examined. Ischemic complications, defined as ischemic chest pain, myocardial infarction, the need for coronary bypass surgery, or death, occurred in 120 patients (9%). Significant multivariate correlates of an ischemic complication were the presence of unstable angina or a totally occluded vessel before angioplasty and diameter stenosis of greater than 30% after angioplasty. Detailed geometric and videodensitometric analysis of the postdilatation angiograms of a subset of 96 consecutive patients was carried out. Ischemic complications occurred in 11 patients (11%). Multivariate analysis revealed that the independent correlates of complications, in decreasing order of importance, were the length of the tear or dissection (p = 0.001), diameter stenosis after angioplasty (p = 0.001), cross-sectional area after dilatation measured by videodensitometric methods (p = 0.013), and the presence of extraluminal contrast (p = 0.044). When tear or dissection occurs during otherwise uncomplicated coronary angioplasty, patients at risk of developing delayed ischemic complications can be identified and may benefit from measures designed to minimize this risk. By controlling for the geometric or mechanical factors that result in tear or dissection, it has been possible to identify factors not previously thought associated with ischemic complications.(ABSTRACT TRUNCATED AT 250 WORDS)

To assess the relationship between left ventricular (LV) response to exercise and myocardial ischaemia, 40 patients with coronary artery disease (CAD) and 17 control subjects underwent radionuclide ventriculography at rest and during semiupright exercise. In 14 of the 40 patients with CAD, radionuclide exercise studies were repeated 20 min after 20 mg of sublingual nifedipine. Patients with CAD had increases in both LV end-diastolic and end-systolic volumes and no change in ejection fraction during exercise. End-systolic volume increased and ejection fraction decreased significantly more in patients with multivessel disease, exercise-induced angina and/or ischaemic ST segment depression. Nifedipine reduced angina and ST-segment depression during exercise, attenuated exercise-induced increase in end-diastolic and end-systolic volumes and improved ejection fraction. This study suggests that in patients with CAD, the response of LV volumes and ejection fraction to exercise is related to the degree of exercise-induced myocardial ischaemia and nifedipine improves exercise LV performance.

Restenosis after percutaneous transluminal coronary angioplasty (PTCA) is strongly associated with incomplete initial dilatation. To determine if oversized PTCA balloons would reduce the restenosis rate without increasing the risk of arterial dissection and acute complications, we prospectively randomized 336 patients to receive either smaller or larger balloons. Thirty-four percent of patients had multivessel disease and 18% had multisite dilatation. One hundred sixty-nine patients were randomized to PTCA with a larger balloon and 167 to PTCA with a smaller balloon. Balloon:artery diameter ratios were 1.13 +/- 0.14 in the larger group and 0.93 +/- 0.12 in the smaller group (p less than 0.001). The trial was halted as clinically important differences in acute complications emerged. Emergency bypass graft surgery, usually for the treatment of arterial dissection, was required in 7.1% of patients in the larger balloon group and 3.6% of patients in the smaller balloon group (p = 0.15). Myocardial infarction (Q wave and non-Q wave) complicated 7.7% of procedures in which large balloons were assigned and 3.0% of procedures in which small balloons were assigned (p = 0.056). There were no deaths in either group. The incidence of bypass surgery was 1.7% when the balloon:artery ratio was less than 0.9, 3.1% when the ratio was 0.9-1.1, and 7.8% when it was greater than 1.1. Stepwise logistic regression analysis demonstrated that larger balloon assignment, multiple lesion dilatation, and multivessel coronary artery disease were independent predictors of emergency surgery. Angiographic restudy rates were 50% in the larger group and 60% in the smaller group (p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Three distinct periods in catheter design have been identified since the advent of percutaneous transluminal coronary angioplasty (PTCA) in 1977. In the first period PTCA was performed using a double-lumen balloon catheter that had a fixed, flexible guidewire at the tip. In the second period, an independent, steerable guidewire and the steerable catheter system were used. In the third period, low-profile catheters were introduced. A total of 2,969 patients who had single-vessel PTCA of a native coronary artery was separated into groups according to the period during which PTCA was performed. Introduction of the steerable catheter system was accompanied by improvement in primary success rate in PTCA attempts on the right coronary artery (78% vs 88%, p less than 0.005). Introduction of the low-profile catheter was accompanied by improved primary success in PTCA attempts on the left anterior descending coronary artery (LAD) (90% vs 94%, p less than 0.005). The percentage of PTCA attempts on the LAD decreased over the 3 periods (70% to 60% to 56%), while the percentage of attempts on the left circumflex artery increased (7% to 12% to 16%). Before steerable and low-profile catheters were used, there were significant differences in ability to reach and cross stenoses among the 3 major coronary arteries. These differences no longer exist. These results indicate that technical improvements and operator experience have made stenoses in all 3 major coronary arteries equally accessible to dilatation catheters and that primary success rates and reasons for failure in these arteries are now similar.

Obstruction to blood flow is accompanied by a pressure gradient across the obstructed site. In certain clinical settings, magnitude of pressure gradient has been used to judge severity of obstruction, and gradient reduction to judge success of an interventional procedure. In percutaneous transluminal coronary angioplasty (PTCA) the relationships between transstenotic pressure gradient, diameter stenosis, and lesion length are imprecisely known. We therefore examined 4263 sets of measurements in patients who underwent PTCA on single, discrete coronary arterial lesions. Multivariate regression analysis demonstrated that pressure gradient was artifactually elevated by about 12 mm Hg at low values of diameter stenosis but increased by the 4th power of stenosis as expected from fluid dynamics models. Pressure gradient was dampened and relatively constant at values of diameter stenosis of 60% or higher, probably because of total or near-total occlusion of the artery. Lesion length was not found to influence pressure gradient. Reductions in diameter stenosis (delta D) and pressure gradient (delta G) were related nonlinearly, with delta D proportional to the square root of delta G, suggesting that a reduction in gradient is directly proportional to an increase in cross-sectional area of the stenosis. The predictive value of final post-PTCA pressure gradients was found: a final gradient of 15 mm Hg or less predicted a final post-PTCA diameter stenosis of 30% or less, with 75% sensitivity and 29% specificity (p less than .01). The results of this study suggest that (1) pressure gradient as currently measured during PTCA is related to diameter stenosis but not to lesion length (2) reductions in pressure gradient and diameter stenosis are nonlinearly related.(ABSTRACT TRUNCATED AT 250 WORDS)

Restenosis after successful PTCA remains a major problem limiting the efficacy of the procedure. The pathophysiologic mechanism of restenosis has been enigmatic so far, but accumulated evidence strongly suggests that intimal hyperplasia is the major mechanism. Based on current understanding of the process of intimal hyperplasia, one unifying concept may be that there are at least two major local biologic determinants influencing this process, lesion characteristics and regional flow dynamics. Lesion characteristics include the plaque structure and the quantity of smooth muscle. These may provide the anatomic substrate that determines the extent of injury and the degree of smooth muscle cell proliferation. The amount of smooth muscle cells in the stenotic lesion activated by injury to undergo proliferation may determine the eventual bulk of the restenotic lesion. In addition, low wall shear stress could promote intimal hyperplasia and cause structural change of vessels to decrease the lumen, whereas high wall shear stress exerts the opposite effects. Intimal hyperplasia after balloon injury is a complex process involving platelets, growth factors, endothelial cells, smooth muscle cells, mechanical injury, wall shear stress, and probably other unknown factors. Platelets not only contribute growth factors such as PDGF but also cause organized thrombus. Different growth factors may be involved in initiating smooth muscle cell proliferation and may come from many different sources, including smooth muscle cells, endothelial cells, and macrophages. Intact confluent endothelial cells may produce heparin sulfates and inhibit intimal proliferation; however, regenerating endothelial cells may have the opposite effect. Thus, the proliferative potential of smooth muscle cells, endothelial recovery, extent of injury, wall shear stress, and other unknown factors may all influence this process. Based on these concepts concerning the biology of restenosis, some research directions concerning potential forms of therapy are proposed.

Seventeen postangioplasty cases were morphologically studied at postmortem. Four of the eleven, early and intermediate cases (few hours to 1 month from angioplasty to death), revealed intraluminal thrombi, although in only two cases were those thrombi occlusive. Almost all of the nine early cases (eight of nine) exhibited intimal disruptions. Except for two of these cases in which circumferential and/or longitudinal dissections were present, the remainder of the intimal cracks were superficial and of limited extent. Limited dissection between intima and media is not considered a serious or detrimental local event. The early cases showed an aneurysmal dilatation of the plaque-free segment of the arterial wall in eccentric plaques. This finding was interpreted as the result of uneven distribution of the dilating force (circumferential stress) on the aterial wall. Late cases (survival over 1 month) revealed characteristic medial and intimal lesions indicative of the initial dilatation injury. It is hypothesized that intrinsic arterial wall changes (medial disruption) at the plaque-free segment and the resulting altered arterial geometry at the site of dilatation have a significant hemodynamic effect on the vascular conduit and may enhance and sustain the myoproliferative intimal response.

Restenosis after coronary angioplasty, a gradual encroachment of the dilated arterial lumen by overgrowth of neointimal cells, occurs in a minority (25% to 30%) of patients. Clinical and anatomic descriptors of those patients who develop restenosis have been identified and suggest a complex, multifactorial etiology. Optimal initial enlargement of the diameter probably reduces the chance of restenosis on geometric grounds alone. The independent predictive value of a low final translesional pressure gradient indicates that adequate blood flow may reduce platelet adhesion and thrombus formation. The importance of the latter factor remains uncertain. Individual proliferative responses to the intimal and medial injury caused by balloon dilatation appear to be modulated by both lesion-specific and patient factors. Lesion-specific factors appear most important and relate to vessel site, tortuosity and branching. These factors are also thought to influence native atherogenesis but the relation between restenosis and atherogenesis remains obscure. Patient risk factors for coronary artery disease also appear to influence restenosis. Procedural factors and risk factor modification may partially modify the restenosis response; however, prevention of restenosis will depend on finding agents that block either stimulation or proliferation of smooth muscle cells.

To determine the importance of predilatation stenosis morphology on the risk of restenosis after percutaneous transluminal coronary angioplasty (PTCA), 500 procedures were randomly chosen for analysis from 3,839 consecutive successful PTCA procedures. Angiographic follow-up was available for 308 patients (62%) at a mean of 7.3 +/- 3.4 months after PTCA. One dilated site was randomly chosen per procedure. One hundred and one sites had documented restenosis (greater than or equal to 50% mean diameter stenosis from multiple projections) by quantitative angiography (33% of all sites restudied and 20% of all sites dilated). Twenty-eight morphologic variables and 20 other angiographic, clinical and procedural variables were analyzed by an observer blinded to clinical outcome. Univariate analysis found post-PTCA percent stenosis greater than 30% (p = 0.005), bend point location (p = 0.01), post-PTCA gradient greater than 15 mm Hg (p = 0.02), angina class III to IV (p = 0.03), age (p = 0.04) and the absence of dissection (p = 0.04) to predict restenosis. Multivariate analysis found only 2 significant (p less than 0.05) independent predictors of restenosis: post-PTCA percent stenosis greater than 30% and bend point location. Restenosis occurred in 41% of lesions located at an end-diastolic vessel angle greater than or equal to 45 degrees compared with 28% in lesions on lesser bends. Thus, only 1 predilatation morphologic characteristic, stenosis location at a bend point, was an important independent predictor of restenosis, and should be considered when assessing patients for PTCA.

Advances in technology and operator experience, and increased use of angiography early after myocardial infarction have led to greater use of percutaneous transluminal coronary angioplasty (PTCA) for chronic, total coronary artery occlusions. To better assess long-term outcome, 257 consecutive patients with successful PTCA of a total occlusion with late angiographic follow-up from 484 patients (53%) with PTCA success were reviewed. The mean +/- standard deviation patient age was 54 +/- 10 years, 79% were men, the duration of total occlusion was 11 +/- 15 weeks and the post-PTCA diameter stenosis was 24 +/- 12%. Eighty-two, 27 and 63% of patients received long-term aspirin, dipyridamole and warfarin therapy, respectively. Angiography at 8 +/- 8 months demonstrated restenosis (greater than or equal to 50% diameter stenosis) in 41% of patients restudied within 6 months and in 66% of patients restudied within 12 months by life table analysis. In multivariate regression analysis of 19 variables, 2 were independently correlated with the occurrence of restenosis: post-PTCA diameter stenosis greater than 30% (p = 0.02) and coronary artery dilated (left anterior descending and right coronary arteries greater than the left circumflex coronary artery) (p = 0.05). In log rank analysis that also considered the timing of angiographic detection of restenosis, dilatation of a proximal left anterior descending stenosis was also a significant predictor of restenosis (p = 0.01), and dilatation within 4 weeks of the presumed time of occlusion was only weakly predictive (p = 0.11).(ABSTRACT TRUNCATED AT 250 WORDS)