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Objective: Our objective was to quantify incremental risk associated with transfusion of packed red blood cells and other blood components on morbidity after coronary artery bypass grafting., Design: The study design was an observational cohort study., Setting: This investigation took place at a large tertiary care referral center., Patients: A total of 11,963 patients who underwent isolated coronary artery bypass from January 1, 1995, through July 1, 2002., Interventions: None., Measurements and Main Results: Among the 11,963 patients who underwent isolated coronary artery bypass grafting, 5,814 (48.6%) were transfused. Risk-adjusted probability of developing in-hospital mortality and morbidity as a function of red blood cell and blood-component transfusion was modeled using logistic regression. Transfusion of red blood cells was associated with a risk-adjusted increased risk for every postoperative morbid event: mortality (odds ratio [OR], 1.77; 95% confidence interval [CI], 1.67-1.87; p<.0001), renal failure (OR, 2.06; 95% CI, 1.87-2.27; p<.0001), prolonged ventilatory support (OR, 1.79; 95% CI, 1.72-1.86; p<.0001), serious infection (OR, 1.76; 95% CI, 1.68-1.84; p<.0001), cardiac complications (OR, 1.55; 95% CI, 1.47-1.63; p<.0001), and neurologic events (OR, 1.37; 95% CI, 1.30-1.44; p<.0001)., Conclusions: Perioperative red blood cell transfusion is the single factor most reliably associated with increased risk of postoperative morbid events after isolated coronary artery bypass grafting. Each unit of red cells transfused is associated with incrementally increased risk for adverse outcome.

Objective: We sought to evaluate magnesium as a neuroprotectant in patients undergoing cardiac surgery with cardiopulmonary bypass., Methods: From February 2002 to September 2003, 350 patients undergoing elective coronary artery bypass grafting, valve surgery, or both were enrolled in a randomized, blinded, placebo-controlled trial to receive either magnesium sulfate to increase plasma levels 1(1/2) to 2 times normal during cardiopulmonary bypass (n = 174) or no intervention (n = 176). Neurologic function, neuropsychologic function, and depression were assessed preoperatively, at 24 and 96 hours after extubation (neurologic) and at 3 months (neuropsychologic, depression). Neurologic scores were analyzed using ordinal longitudinal methods, and neuropsychologic and depression inventory data were summarized by principal component analysis, followed by linear regression analysis using component scores as response variables., Results: Seven (2%) patients had a postoperative stroke, 2 (1%) in the magnesium and 5 (3%) in the placebo group (P = .4). Neurologic score was worse postoperatively in both groups (P < .0001); however, magnesium group patients performed better than placebo group patients (P = .0001), who had prolonged declines in short-term memory and reemergence of primitive reflexes. Three-month neuropsychologic performance and depression inventory score were generally better than preoperatively, with few differences between groups (P > .6); however, older age (P = .0006), previous stroke (P = .003), and lower education level (P = .0007) were associated with worse performance., Conclusions: Magnesium administration is safe and improves short-term postoperative neurologic function after cardiac surgery, particularly in preserving short-term memory and cortical control over brainstem functions. However, by 3 months, other factors and not administration of magnesium influence neuropsychologic and depression inventory performance.

Background: The importance of moderate ischemic mitral regurgitation in patients presenting for coronary artery bypass grafting (CABG) is controversial. Therefore, we tracked the course of unrepaired moderate ischemic mitral regurgitation after CABG surgery alone, identified factors associated with worsening postoperative ischemic mitral regurgitation, and assessed the impact of unrepaired moderate ischemic mitral regurgitation on survival., Methods: From 1980 to 2000, 467 patients with moderate ischemic mitral regurgitation underwent CABG alone. The course of unrepaired mitral regurgitation was estimated by a longitudinal analysis of 267 follow-up echocardiograms from 156 patients. The survival impact of moderate ischemic mitral regurgitation was determined among propensity-matched patients with and without ischemic mitral regurgitation., Results: Mitral regurgitation was dynamic early postoperatively. Immediately postoperatively, it was absent or mild in 73% and severe in 6%; by 6 weeks, these figures were 40% and 22%, respectively. The course of postoperative mitral regurgitation was not associated with the preoperative extent of coronary artery disease or left ventricular dysfunction. Five-year survival of matched bypass patients without ischemic mitral regurgitation was 85% compared with 73% for patients with moderate ischemic mitral regurgitation (p = 0.003)., Conclusions: Moderate ischemic mitral regurgitation does not reliably resolve with CABG surgery alone and is associated with reduced survival. Therefore, a mitral valve procedure may be warranted for such patients presenting for CABG. A randomized trial comparing strategies of revascularization with mitral valve repair and revascularization alone is required to determine optimal treatment.

Background: Preoperative atrial fibrillation has been identified as a risk factor for reduced long-term survival after coronary artery bypass grafting. This study sought to determine whether atrial fibrillation is merely a marker for high-risk patients or an independent risk factor for time-related mortality., Methods: From 1972 to 2000, 46,984 patients underwent primary isolated coronary artery bypass grafting; 451 (0.96% prevalence) had electrocardiogram-documented preoperative atrial fibrillation (n = 411) or flutter (n = 40). Characteristics of patients with and without atrial fibrillation were contrasted by multivariable logistic regression to form a propensity score. With this, comparable groups with and without atrial fibrillation were formed by pairwise propensity-matching to assess survival., Results: Patients with preoperative atrial fibrillation were older (67 +/- 9.0 versus 59 +/- 9.8 years, p < 0.0001), had more left ventricular dysfunction (66% versus 52%, p < 0.0001) and hypertension (73% versus 59%, p < 0.0001), but less severe angina (39% moderate or severe versus 49%, p < 0.0001). Many of these factors are themselves predictors of increased time-related mortality. In propensity-matched patients, survival at 30 days and at 5 and 10 years for patients with versus without atrial fibrillation was 97% versus 99%, 68% versus 85%, and 42% versus 66%, respectively, a survival difference at 10 years of 24%. Median survival in patients with atrial fibrillation was 8.7 years versus 14 years for those without it., Conclusions: Atrial fibrillation in patients undergoing coronary artery bypass grafting is a marker for high-risk patients; in addition, atrial fibrillation itself substantially reduces long-term survival. Thus, if patients in atrial fibrillation require surgical revascularization, it is appropriate to consider performing a concomitant surgical ablation procedure.

Objective: Multiple reports demonstrate that off-pump surgery reduces the early morbidity associated with coronary artery bypass grafting. To determine if there are any differences in later outcomes, we compared midterm results of propensity-matched patients who underwent off- and on-pump coronary artery bypass grafting., Methods: From January 1997 to July 2000, 481 patients underwent off-pump coronary artery bypass grafting and 3231 underwent on-pump coronary artery bypass grafting. Propensity matching was used to match 406 patients from each group. Previously, the propensity-matched off-pump patients were found to have had significantly fewer bypass grafts. These 812 patients were followed for time-related events, including death, myocardial infarction, percutaneous coronary intervention, coronary reoperation, and the combined end point of all-cause mortality, myocardial infarction, and all coronary reintervention. Follow-up was 95% complete., Results: At 4 years, survival was 87.5% after off-pump and 91.2% after on-pump coronary artery bypass grafting (P =.2); freedom from myocardial infarction was 92.6% and 95.7% (P =.7), respectively; freedom from percutaneous coronary intervention was 94.3% and 95.5% (P =.9), respectively; freedom from coronary reoperation was 98.1% and 99.0% (P =.4), respectively; and freedom from the combined end point of all-cause mortality, myocardial infarction, and coronary reintervention was 75.2% and 82.9% (P =.14), respectively., Conclusions: Off-pump and on-pump coronary artery bypass grafting results in equivalent midterm outcomes. Fewer bypass grafts in the off-pump patients did not decrease survival or increase ischemic events at 4 years.

Background: In coronary arteries with moderate stenosis, competitive flow may lead to internal thoracic artery (ITA) graft occlusion. The goals of this study were to determine if competitive flow reduces ITA patency, and if there is a degree of coronary stenosis below which ITAs should not be used., Methods: From 1972 to 1999, 50,278 patients underwent primary coronary artery bypass grafting (CABG). Of these, 2,002 had at least one ITA graft and postoperative angiography before coronary reintervention; 2,999 angiograms of 2,121 ITAs were made. Time-related ITA occlusion was modeled using longitudinal analysis to identify its risk factors while accounting for lack of independence introduced by repeated angiography and multiple ITA anastomoses per patient. Proximal coronary stenosis (maximum preoperative stenosis between ITA anastomosis and aorta) was the surrogate for competitive flow., Results: Unadjusted ITA patency was 93%, 89%, 90%, and 92% at 1, 5, 10, and 15 years after CABG. Risk factors associated with ITA occlusion were lesser degree of proximal coronary stenosis (p < 0.0001); longer time from CABG in grafts to non-left anterior descending coronary arteries (p < 0.0001); female sex (p = 0.0003); later date of CABG (p = 0.01); right ITA (p < 0.0001); and smoking (p < 0.0001). In all arteries, as preoperative proximal coronary stenosis decreased, ITA patency declined; however, at no degree of stenosis was there a sharp decline., Conclusions: Internal thoracic artery patency decreases as coronary competitive flow increases. However, the nature of this relationship indicates ITAs should not be abandoned at moderate grades of stenosis.

Objective: To compare hospital outcomes of on-pump and off-pump coronary artery bypass surgery., Methods: From 1997 to 2000, primary coronary artery bypass grafting was performed in 481 patients off pump and in 3231 patients on pump. Hospital outcomes were compared between propensity-matched pairs of 406 on-pump and 406 off-pump patients. The 2 groups were similar in age (P =.9), left ventricular function (P =.7), extent of coronary artery disease (P =.5), carotid artery disease (P =.4), and chronic obstructive pulmonary disease (P =.5). However, off-pump patients had more previous strokes (P =.05) and peripheral vascular disease (P =.02); on-pump patients had a higher preoperative New York Heart Association class (P =.01)., Results: In the matched pairs the mean number of bypass grafts was 2.8 +/- 1.0 in off-pump patients and 3.5 +/- 1.1 in on-pump patients (P <.001). Fewer grafts were performed to the circumflex (P <.001) and right coronary (P =.006) artery systems in the off-pump patients. Postoperative mortality, stroke, myocardial infarction, and reoperation for bleeding were similar in the 2 groups. There was more encephalopathy (P =.02), sternal wound infection (P =.04), red blood cell use (P =.002), and renal failure requiring dialysis (P =.03) in the on-pump patients., Conclusions: Both off- and on-pump procedures produced excellent early clinical results with low mortality. An advantage of an off-pump operation was less postoperative morbidity; however, less complete revascularization introduced uncertainty about late results. A disadvantage of on-pump bypass was higher morbidity that seemed attributable to cardiopulmonary bypass.

Background: HDL cholesterol (HDL-C) is an important independent predictor of atherosclerosis, yet the role that HDL-C may play in the prediction of long-term survival after CABG remains unclear. The risk associated with a low HDL-C level in post-CABG men has not been delineated in relation to traditional surgical variables such as the use of arterial conduits, left ventricular function, and extent of disease., Methods and Results: We performed a prospective, observational study of 432 men who underwent CABG between 1978 and 1979 in whom preoperative HDL-C values were available. Baseline lipid and lipoprotein values, history of diabetes mellitus and hypertension, left ventricular ejection fraction, extent of disease, and use of internal thoracic arteries were recorded. Hazard ratios (HRs) were determined in the patients with and without a low HDL-C level, which was defined as the lowest HDL-C quartile (HDL-C 35 mg/dL) were 50% more likely to survive at 15 years than were patients with low HDL-C level (35 mg/dL were 50% more likely to survive without a subsequent myocardial infarction or revascularization (HR 1.42, P:=0.02)., Conclusions: HDL-C is an important predictor of survival in post-CABG patients. In this study of >8500 patient-years of follow-up, HDL-C was the most important metabolic predictor of post-CABG survival. One third fewer patients survive at 15 years if their HDL-C levels are

We performed a prospective observational study on 6,602 subjects (94% for 5 years and 34% for 10 to 15 years) who underwent coronary artery bypass graft surgery (CABG) between 1982 and 1992. We examined whether triglyceride concentrations adjusted for other factors (total cholesterol, history of diabetes mellitus, systemic hypertension, left ventricular function, number of coronary arteries significantly narrowed, and use of the internal thoracic arteries) explained total and event-free survival. These analyses were duplicated within gender (1,354 women and 5,248 men). This approach allowed a determination of any gender-related disparities in lipid predictors. Triglycerides in the highest quartile were associated with an increased risk of mortality of 20% (confidence interval [CI] 1.0 to 1.4). Similar risk was seen for event-free survival. Although there was no evidence of gender differences in adjusted survival (p = 0.33), a gender by triglyceride interaction (p = 0.004) indicated that the response to high triglycerides as related to survival did differ by gender. Specifically, women had a dramatically higher risk (hazard ratio [HR] 1.5, CI 1.1 to 2.1) than men (HR 1.1, CI 0.9 to 1. 3). Both men and women did have triglyceride-associated risk with regard to event-free survival (HR in men 1.2, CI 1.1 to 1.4; HR in women 1.4, CI 1.1 to 1.8). Examination of high-density lipoprotein cholesterol in a subcohort did not eliminate the observed triglyceride effects. Thus, triglyceride baseline values are primary determinants (similar to baseline left ventricular function or extent of coronary disease) for long-term total and event-free mortality after CABG in women but not in men.

Objective: Multiple strategies to achieve some degree of myocardial revascularization are available. In some, less complete revascularization is accepted to limit invasiveness. To examine the issues of incomplete revascularization, we assessed the long-term impact of additional non-left anterior descending coronary artery stenoses in patients undergoing only grafting of the left internal thoracic artery to the left anterior descending coronary artery., Methods: A total of 2067 patients underwent primary isolated grafting of the left internal thoracic artery to the left anterior descending coronary artery from 1971 to 1997. Of these, 26% and 13% had 2- and 3-system disease, respectively. Multivariable analyses of survival and reintervention were performed in the hazard function domain for 27,683 patient-years of follow-up (mean 14 +/- 6.7)., Results: Survival was 99%, 88%, and 62% at 1, 10, and 20 years. Right coronary artery or left circumflex system disease of 50% or more (P =.02) and particularly high-grade (>/=70%) left circumflex (P =.01) and proximal right coronary artery disease (P =.01), as well as any degree of left main trunk stenosis (P <.0001), were associated with reduced long-term survival. Compared with 75% 20-year survival in patients with no non-left anterior descending disease, those with either left circumflex or left main trunk disease experienced a 44% survival, and those with proximal right coronary artery disease, 42%. The most common stated reason for incomplete revascularization was small vessel size. Freedom from reintervention was 89% and 65% at 10 and 20 years, respectively. High-grade left main trunk disease, but, in contrast, mid or distal disease of the right coronary artery, and not left circumflex disease, were risk factors for reintervention., Conclusions: These findings call into question the long-term appropriateness of interventions whose strategy includes leaving unrevascularized segments in territories not in the distribution of the left anterior descending coronary artery.

Background: As second coronary artery bypass graft (CABG) operations are becoming more common in elderly patients, we conducted a retrospective analysis of risk factors for in-hospital and late outcome in patients aged 70 and over., Methods: We reviewed records of 739 patients who underwent second CABG at age 70 or older at our institution between 1983 and 1993. Preoperative, operative, and postoperative variables were analyzed to identify predictors of in-hospital and long-term mortality., Results: The mean age (+/- standard deviation) at reoperation was 74 +/- 3 years and the mean interval after primary operation was 130 +/- 55 months. In-hospital mortality was 7.6% (n = 56). Preoperative factors associated with increased in-hospital mortality were preoperative creatinine greater than 1.6 mg/dL (p < 0.001), emergency operation (p < 0.001), female sex (p = 0.012), moderate or severe left ventricular dysfunction (p = 0.049), and left main coronary disease (p = 0.045). In-hospital, actuarial survival was 75% at 5 years and 49% at 10 years. Cardiac event-free survival was 60% at 5 years and 27% at 10 years. The factors independently associated with increased late death were hematocrit (p = 0.046), diabetes (p = 0.011), peripheral vascular disease (p < 0.001), left ventricular function (p < 0.001), history of cancer (p = 0.016), preoperative nonsinus rhythm (p = 0.003), anticoagulation or antiplatelet therapy (p = 0.018), postoperative encephalopathy (p = 0.001), and postoperative stroke (p = 0.014)., Conclusions: CABG reoperation can have excellent results for many elderly patients, but mortality is markedly higher when elderly patients have certain risk factors and comorbidities, alone or in combination. This information should be helpful in educating patients before they decide whether to choose reoperation.

Background: Heparin-coated circuits in cardiopulmonary bypass have been shown to decrease the systemic inflammatory responses associated with cardiopulmonary bypass. Previous clinical studies on low-risk patients who had coronary artery bypass grafting (CABG) and received full-dose systemic heparin did not have clearly improved clinical outcomes. We hypothesized that the beneficial effects of heparin-coated circuits might be seen in patients who had cardiac reoperations., Methods: Three hundred fifty patients who had reoperation with CABG only (58%), or with valve operations (42%) were randomly assigned to receive either a heparin-coated (Duraflo II; study group) or uncoated (control group) circuit. Clinical outcomes were compared and the variables were analyzed using the following three groups: entire populations of study group and control group, subgroup of patients who had CABG reoperation only, and a subgroup who had valve reoperation or combined valve and CABG reoperation., Results: Preoperative variables were the same in both groups. No difference in clinical outcomes could be demonstrated except that the percentage of patients with major bleeding episodes was significantly lower in the study group (1.2% versus 5.4%, p = 0.035). In the subgroup analysis of patients who had valve reoperations, lower blood transfusion requirements in the intensive care unit (p = 0.013) were found in the study group. When the subgroup of patients who had CABG reoperations was analyzed separately, there was a trend toward less reoperation for bleeding in the study group (0% versus 4.0%, p = 0.058)., Conclusions: We conclude that the use of heparin-coated circuits was safe and imparted protection from reoperations for bleeding and major bleeding episodes. Material-independent blood activation (eg, blood-air interface and cardiotomy suction) blunted the total effect of the heparin-coated surface.

Objective: Does the use of bilateral internal thoracic artery (ITA) grafts provide incremental benefit relative to the use of a single ITA graft?, Methods: We conducted a retrospective, nonrandomized, long-term (mean follow-up interval of 10 postoperative years) study of patients undergoing elective primary isolated coronary bypass surgery who received either single (8123 patients) or bilateral ITA grafts (2001 patients), with or without additional vein grafts. Multiple statistical methods including propensity score matching, and multivariable parsimonious and nonparsimonious risk factor analyses were used to address the issues of patient selection and heterogeneity., Results: In-hospital mortality was 0.7% for both the bilateral and single ITA groups. Survival for the bilateral ITA group was 94%, 84%, and 67%, and for the single ITA group 92%, 79%, and 64% at 5, 10, and 15 postoperative years, respectively (P <.001). Death, reoperation, and percutaneous transluminal coronary angioplasty were more frequent for patients undergoing single rather than bilateral ITA grafting, and this observation remained true despite multiple adjustments for patient selection, sampling, and length of follow-up. The differences between the bilateral and single ITA groups were greatest in regard to reoperation. The extent of benefit of bilateral ITA grafting varied according to patient-related variables, but no patient subsets were identified for whom single ITA grafting could be predicted to provide an advantage., Conclusions: Patients who received 2 ITA grafts had decreased risks of death, reoperation, and angioplasty.

Background: The purpose of this study was to determine the prevalence, outcome, and operative strategies for patients having injury to a patent left internal thoracic artery (LITA) graft to the left anterior descending coronary artery (LAD) at coronary reoperation., Methods: Of 655 patients with a patent LITA graft to the LAD undergoing coronary reoperation from 1986 to 1997, 35 (5.3%) sustained intraoperative injury to the LITA graft., Results: Strategies to restore flow to the LAD included new saphenous vein graft to the LAD in 15 patients, saphenous vein graft to the LITA stump in 7, saphenous vein graft to the LAD and repair of the LITA graft in 6, and other strategies in 7. All or part of the LITA graft to the LAD was salvaged in 20 patients (57%). Fourteen patients (40%) sustained perioperative myocardial infarction, and 3 patients died (8.6%). The 3 patients who died all had stenosis or thrombosis of the graft to the LAD documented at autopsy., Conclusions: We conclude that (1) the prevalence of injury to a patent LITA graft is 5.3%; (2) a variety of techniques can be used to restore blood flow to the LAD; and (3) ineffective revascularization of the LAD in this situation is associated with operative mortality. At primary coronary artery bypass grafting, the LITA pedicle should be positioned in the left chest away from the posterior sternal table; this strategy may minimize the risk of LITA graft injury at coronary reoperation.

Background: The collective impact of advances in medical, surgical, and anesthetic care on the characteristics and outcomes of patients who undergo coronary artery bypass grafting was assessed., Methods: We compared the demographic and clinical characteristics, preoperative risk factors, morbidity, and mortality of two groups of patients who underwent coronary artery bypass grafting in isolation or in combination with other procedures between July 1, 1986, and June 30,1988 (group 1, n = 5,051), and between January 1, 1993, and March 31, 1994 (group 2, n = 2,793). The patients were stratified according to their preoperative risk level. Outcome measures consisted of changes in preoperative risk categories; hospital mortality rates; overall and risk-adjusted major cardiac, neurologic, pulmonary, renal, and septic morbidity rates; and intensive care unit length of stay., Results: Changes in the distribution of risk categories, from a median of 2 to 4 on a 9-point scale (p < 0.001), indicated that patients in group 2 were at significantly higher risk than those in group 1. The risk-adjusted mortality rate did not change (2.8% to 2.9%; p = 0.15), but the risk-adjusted morbidity rate decreased significantly (14.5% to 8.8%; p < 0.001)., Conclusions: At our institution, patients who undergo coronary artery bypass grafting are now at greater preoperative risk at the time of hospital admission. However, their morbidity rate is significantly lower and their mortality rate is unchanged, results that we attribute to the collective impact of changes in our medical and surgical procedures.

Background: Third coronary artery bypass operations are technically difficult and are associated with increased risk., Methods: We reviewed the cases of 469 patients who had undergone a third isolated coronary artery bypass operation and used univariate and multivariate testing to examine the effect of preoperative and operative variables on outcome and costs., Results: The in-hospital mortality was 7.0% (33 patients). Advanced age and severe symptoms were found to increase risk (both p < 0.05): the mortality was 14% (n = 74) in patients 70 years old or older who had severe symptoms. However, the overall mortality for 1993 through 1995 was 4.3% (5/117) and only one death (1.3%) occurred among the 79 patients who were less than 70 years old. The late survival rate was 94%, 84%, and 66% at 1, 5, and 10 postoperative years, respectively, and predictors of decreased late survival were advanced age, abnormal left ventricular function, and diabetes (all p < 0.05). Again, age of 70 years or more was a predictor of a poor outcome. Only 52% of patients in that subgroup (including both early and late mortality) were alive 5 years after operation. Analysis of direct hospital costs showed that the mean costs of third coronary artery bypass operations were 21% higher than the mean costs of primary operations but that the elevation in the mean costs for third operations was related to very high costs in 4 patients. Sex was found to influence the cost of both primary and third operations (increased cost for women)., Conclusions: Unfavorable outcomes after third coronary artery bypass operations have been associated with preoperatively definable variables, particularly age of 70 years or more. The in-hospital mortality in patients younger than 70 was low, and long-term survival in this group has been favorable. The increased hospital costs associated with third operations are related to high costs in only a few patients and have been unpredictable.

Background: This study was performed to develop an intensive care unit (ICU) admission risk score based on preoperative condition and intraoperative events. This score provides a tool with which to judge the effects of ICU quality of care on outcome., Methods: Data were collected prospectively on 4,918 patients (study group n = 2,793 and a validation data set n = 2,125) undergoing coronary artery bypass grafting alone or combined with a valve or carotid procedure between January 1, 1993, and March 31, 1995. Data were analyzed by univariate and multiple logistic regression with the end points of hospital mortality and serious ICU morbidity (stroke, low cardiac output, myocardial infarction, prolonged ventilation, serious infection, renal failure, or death)., Results: Eight risk factors predicted hospital mortality at ICU admission, and these factors and five others predicted morbidity. A clinical score, weighted equally for morbidity and mortality, was developed. All models fit according to the Hosmer-Lemeshow goodness-of-fit test. This score applies equally well to patients undergoing isolated coronary artery bypass grafting., Conclusions: This model is complementary to our previously reported preoperative model, allowing the process of ICU care to be measured independent of the operative care. Sequential scoring also allows updated prognoses at different points in the continuum of care.

Objectives: It is not known whether the results of randomized trials comparing coronary artery bypass grafting to percutaneous transluminal coronary angioplasty for initial revascularization apply to repeat revascularization in patients with prior bypass grafts. We studied the differences between the patients with prior bypass grafts referred for surgery or angioplasty to identify the clinical and angiographic characteristics that correlated best with either choice and to find clues that might aid in selecting one treatment over the other., Methods: Between 1992 and 1994, 870 patients underwent first isolated reoperation and 793 patients underwent first balloon angioplasty after a previous operation. A jeopardy score (0 to 8 points) was derived for each patient on the basis of the relative size of the ischemic territory. Clinical and angiographic data were analyzed for association with the revascularization strategy., Results: The following characteristics were more prevalent in the reoperation group: male sex, diabetes, hypertension, valvular disease, normocholesterolemia, and severe left ventricular systolic dysfunction; fewer functioning venous and arterial grafts; and a higher jeopardy score (p < 0.01 for all) than in the angioplasty group. A higher jeopardy score, diabetes, and a lower number of functioning arterial or venous grafts were strong, independent predictors of referral for reoperation (p < 0.01 for all). In hospital death and Q-wave infarction (p < 0.01 for both) were more frequent in the reoperation group., Conclusions: Reoperation was the revascularization procedure of choice when larger regions of myocardium were in jeopardy. Angioplasty was more frequently chosen in the presence of a patent arterial graft to the left anterior descending coronary artery or multiple functioning bypass grafts. Reoperation was associated with a higher risk of in-hospital complications than angioplasty.

From 1980 through 1990, 9,145 patients had balloon angioplasty with failure of the procedure requiring emergent surgical revascularization within 24 hours occurring in 253 patients (2.8%). Patients were divided into two cohorts based on the date of the percutaneous transluminal coronary angioplasty (PTCA): 1980 to 1985 (n = 109) and 1986 to 1990 (n = 144). The incidence of PTCA failure was 3.8% during 1980 to 1985 (109/2,903) and decreased to 2.3% (144/6,242) for 1986 to 1990. Comparison of pre-PTCA patient characteristics between the two periods showed that only a history of a previous PTCA and class III or class IV symptoms were more common in the recent years (p < or = 0.05). In-hospital mortality after emergency operation was 4.6% (5/109) during 1980 to 1985 and 7.6% (11/144) from 1985 to 1990 (p = not significant). This trend toward increased mortality appeared to be related to an increased number of patients who underwent operation in a state of severe hemodynamic compromise in the more recent period. The in-hospital mortality rate for patients in shock or undergoing cardiopulmonary resuscitation was 28.3% (13/46) compared with 1.4% (3/207) for patients with less severe hemodynamic derangement (p < 0.001). Use of the intraaortic balloon pump preoperatively increased from 12.8% to 32.6% (p < 0.01). Late survival was 92% at 2 and 87% at 5 postoperative years. Although the incidence of PTCA failure necessitating emergent surgical intervention has decreased over time, there has been a trend toward an increased in-hospital mortality rate for those patients that does not appear to be related to more severe pre-PTCA characteristics.(ABSTRACT TRUNCATED AT 250 WORDS)

Background: Internal thoracic artery (ITA) conduits are known to provide long-term patency and increased patient survival with low morbidity after coronary artery bypass grafting (CABG). Excellent clinical results with the ITA have stimulated interest in additional arterial grafts., Methods and Results: To review our experience and evaluate postoperative complications associated with these new conduits, from May 1985 to September 1993, we studied 290 patients who underwent CABG using additional arterial conduits. The right gastroepiploic artery (GEA) was used in 152 patients and the inferior epigastric artery (IEA) was used in 130 patients. Eight patients with both GEA and IEA grafts were excluded. Patient records were analyzed as to preoperative characteristics, angiographic findings, operative data, and postoperative complications. Statistical analysis was done using the Pearson chi 2 statistic and the t test. Ninety-eight percent of patients received one concomitant ITA graft, and the majority of patients in both groups had bilateral ITA grafts. The GEA group had a higher proportion of reoperations (GEA group, 54%; IEA group, 16%; P < .001), previous myocardial infarction (MI) (GEA group, 67%; IEA group, 50%; P = .004) and New York Heart Association class IV (GEA group, 28%; IEA group, 6%; P = .001). The IEA group was generally slightly older (IEA group, 56 years; GEA group, 52 years; P = .001). Hospital mortality (GEA group, 4%; IEA group, 0.8%) and postoperative morbidity (mediastinal bleeding, infection, stroke, MI, and low cardiac output) were not significantly different between the two groups or from our experience with routine CABG using the ITA. Three intraabdominal complications occurred in the GEA group: 2 episodes of bleeding and 1 of pancreatitis. One patient in the IEA group had abdominal wall bleeding. With overall short follow-up, angiographic patency in a small number of patients has been good: 80% for the GEA group and 85.7% for the IEA group., Conclusions: We conclude that the morbidity associated with these additional arterial conduits is low and is comparable with that associated with routine CABG using the ITA. Currently we use the ITA for primary targets and alternative arterial conduits for vessels of secondary importance or when the ITA and/or saphenous vein is not available.

From 1988 through 1991, 1663 patients underwent a first reoperation for isolated coronary bypass grafting with 62 (3.7%) in-hospital deaths. At the primary operation, 575 patients had received at least one internal thoracic artery graft and 489 patients had at least one patent internal thoracic artery graft present at the time of reoperation. At reoperation, 1014 patients received at least one internal thoracic artery graft, 10 received an inferior epigastric graft, and 37 received a gastroepiploic graft. Of 489 patients with patent internal thoracic artery grafts at reoperation, the internal thoracic artery was damaged in 17 (3.5%); of 428 patients with a patent internal thoracic artery graft to the left anterior descending coronary artery, 14 (3.3%) had graft damage necessitating regrafting. All patients with damaged internal thoracic arteries survived. Multivariate testing of variables for their association with in-hospital mortality identified no internal thoracic artery graft at either primary surgery or reoperation (p < 0.0001), a history of congestive heart failure (p < 0.0001), advancing age (p = 0.018), female gender (p = 0.029), and emergency operation (p = 0.01) as factors linked to increased risk. Left ventricular function, left main stenosis, extent of native coronary atherosclerosis, and the interval between operations did not influence mortality. Furthermore, the presence of an atherosclerotic vein graft to the left anterior descending coronary artery a factor shown to increase in-hospital risk in previous studies did not increase risk during these years. We attribute the observation that patent internal thoracic artery and atherosclerotic vein grafts do not appear to be factors specifically increasing the risk of reoperation to the use of retrograde cardioplegic solution and increased surgical experience. The use of internal thoracic artery grafts at a primary operation does not increase the risk of a reoperation, and the use of internal thoracic artery grafts at reoperation does not increase in-hospital morbidity or mortality.

To assess the long-term results of the surgical treatment of isolated left anterior descending coronary artery stenosis and compare surgical strategies for graft selection, we reviewed 100 consecutive patients receiving left internal mammary artery-to-left anterior descending artery grafts and 100 consecutive patients who received a saphenous vein autograft to the left anterior descending artery. All patients underwent operation from 1971 through 1973. The internal mammary artery and saphenous vein graft groups were equivalent with regard to preoperative clinical and angiographic variables, except that patients receiving left internal mammary artery grafts had a higher prevalence of noncritical disease (less than 50% stenosis) in the circumflex and right coronary arteries than did the saphenous vein graft group. Mean follow-up for the internal mammary artery and saphenous vein graft groups was 18.7 years and 20.7 years, respectively. The 18-year outcome was superior for the internal mammary artery group. Cox regression analysis confirmed that patients with left internal mammary artery grafts had superior survival, intervention-free survival, and event-free survival (all p < 0.01). The presence of noncritical disease in other vessels adversely affected intervention-free survival and event-free survival for both groups (all p < 0.03) and decreased survival for the saphenous vein graft group (p = 0.01) but not for the internal mammary artery group (p = 0.24). We conclude that in long-term follow-up of surgically treated isolated left anterior descending artery stenosis (1) the left internal mammary artery consistently yields better overall and intervention-free survival than does the saphenous vein graft, (2) outcome is influenced by the presence of noncritical disease in other vessels at the initial operation, and (3) deployment of the left internal mammary artery in the treatment of isolated left anterior descending artery stenosis yielded 18 years of intervention-free survival of 60.5% and provides a standard for comparison with other forms of therapeutic intervention.

Reoperative coronary artery bypass grafting secondary to saphenous vein graft (SVG) stenosis is a mushrooming problem. The internal thoracic artery graft (ITA) provides superior long-term patency, but its flow is limited and may be inadequate to meet large myocardial demands. To evaluate the efficacy of the ITA as a replacement conduit for a stenotic SVG, 387 consecutive patients undergoing reoperative bypass grafting from 1985 to 1990 with a stenotic SVG to a totally obstructed left anterior descending coronary artery (LAD) were analyzed. The patients were divided into four groups according to the management of the previously placed SVG. Group I (n = 155) underwent graft replacement with a new SVG. Group II (n = 90) received an ITA with the old SVG left intact. In group III (n = 37), an ITA was placed to the LAD with an SVG to the diagonal (old graft interrupted). Group IV (n = 104) had an ITA only to the LAD (old graft interrupted). There were 14 deaths (3.6%). Mortality rate was 7.9% for group IV and 2.1% for groups I through III (p = 0.01). Multivariate analyses identified advancing age (p = 0.001), ITA only (p = 0.001), and female sex (p = 0.04) as independent predictors of operative mortality. Evidence of hypoperfusion in the distribution of the LAD was present in 19 patients, all of whom were in group IV (18.9%). Predictors of hypoperfusion were moderate/severe left ventricular function (p = 0.02) and ITA to the LAD with interruption of the old graft (p = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Does coronary artery reoperation improve the survival of patients with stenoses in saphenous vein bypass grafts to coronary arteries? To examine this question, we retrospectively reviewed 1117 patients who had coronary bypass grafting and then underwent a postoperative coronary angiogram that showed a stenosis (> or = 20%) of at least one vein graft. Reoperation within 1 month of the postoperative angiogram was performed for 394 patients (REOP group) whereas 723 patients (MED group) received initial medical treatment (no reoperation or percutaneous transluminal coronary angioplasty within 1 year). Compared with the MED group, patients in the REOP group were older, more symptomatic, more likely to have left main stenosis, and had fewer patent bypass grafts (all p < 0.001). In-hospital mortality for the REOP group was 4.3%. Mean postangiogram follow-up of the entire group was 73 months. On the basis of the interval between the primary operation and the postoperative angiogram, patients were designated as having early (< 5 years) or late (> or = 5 years) saphenous vein graft stenosis. Univariate and multivariate analyses were used to identify factors influencing the survival of these subgroups. Reoperation was not identified as a variable improving the survival of patients with early vein graft stenoses. For patients with late vein graft stenoses, moderate or severe impairment of left ventricular function (p < 0.0001), advanced age (p < 0.0001), triple-vessel or left main stenosis (p = 0.0011), and stenosis in a vein graft to the left anterior descending artery (p = 0.0019) decreased survival, whereas reoperation improved survival (p = 0.0007). The improvement in survival with reoperation was particularly strong for patients with a stenotic vein graft to the left anterior descending artery. For that subset, survival was 84% and 74% for the REOP group versus 76% and 53% for the MED group at 2 and 4 years after catheterization, respectively (p = 0.004). For patients with stenotic vein grafts to the right coronary artery or circumflex coronary artery (or both), survival was 92% and 87% for the REOP group versus 89% and 78% for the MED group at 2 and 4 years after catheterization, respectively (p = 0.13). Even for patients with class I or II symptoms, reoperation prolonged survival (p = 0.002 with multivariate testing). Reoperation improves the survival of patients with late vein graft stenoses, particularly those with stenotic grafts to the left anterior descending coronary artery.

The influence of coronary artery stenoses on patient survival and event-free survival is known, but no studies have reported the long-term outcome of patients with stenoses in saphenous vein bypass grafts. We retrospectively studied 723 patients who underwent a postoperative angiographic study that documented a stenosis of 20% to 99% in at least one saphenous vein graft and who did not undergo reoperation or percutaneous transluminal coronary angioplasty within 1 year after that catheterization. The mean follow-up interval was 83 months (range 1 to 237 months). For comparison, a group of 573 patients who underwent a postoperative catheterization that did not show any vein graft stenosis were also followed up. Cox regression analyses were used to identify predictors of late survival, reoperation-free survival, and event-free survival. For the entire group of patients with stenotic vein grafts, moderate or severe impairment of left ventricular function (p less than 0.001), interval between operation and catheterization (p less than 0.001), older age (p = 0.001), triple-vessel or left main coronary artery disease (p = 0.004), and stenosis of the vein graft to the left anterior descending coronary artery (p = 0.09) were associated with decreased late survival. Patients with an operation-to-catheterization interval greater than or equal to 5 years were at particularly high risk, and multivariate analyses of that subgroup confirmed that a stenotic graft to the left anterior descending artery was a strong predictor of decreased survival (p less than 0.001), decreased reoperation-free survival (p less than 0.001), and decreased event-free survival (p less than 0.001). Patients greater than or equal to 5 years postoperatively with greater than or equal to 50% stenosis of vein grafts to the left anterior descending artery had survival of 70% and 50% at 2 and 5 years after catheterization, compared with 97% and 80% for those with greater than or equal to 50% stenosis of the native left anterior descending artery (p = 0.002). Late vein graft stenoses are more dangerous than native coronary stenoses. Late stenoses in saphenous vein grafts to the left anterior descending coronary artery predict a high rate of death and cardiac events and are an indication for reoperation.

Of 6,504 consecutive patients who underwent isolated coronary bypass grafting in 1985 to 1987, 72 (1.1%) patients experienced sternal wound complications. Ten patients (14%) with wound complications died of multi-system failure. Only the patients with negative cultures fared well; of the bacterial culture categories, polymicrobial infection carried the worst prognosis. Effects of recurring infection were seen throughout the first year. Patients, grouped according to conduits received, experienced these wound complication rates: vein grafts only, 11/1,085 (1.0%); one internal thoracic artery, 38/4,073 (0.9%); and bilateral internal thoracic artery grafts, 23/1,346 (1.7%). There were no significant differences in wound complication rates between primary and reoperation patients or among conduit groups. By logistic regression analysis, the relative risk for patients with diabetes and bilateral internal thoracic artery grafting was 5.00 (95% confidence interval, 2.4 to 10.5). Operation time as a continuous variable increased the relative risk of wound complication 1.47 times per hour (1.3 to 1.7); obesity, 2.90 times (1.8 to 4.8); and blood units as continuous variable, 1.05 times per unit (1.01 to 1.10). Bilateral internal thoracic artery grafting in nondiabetic patients carried no greater risk of wound complication than that in patients with vein grafts only or with one internal thoracic artery graft.

The excellent results of coronary artery bypass with the internal mammary artery and the increasing numbers of patients who need coronary reoperations, but for whom conventional bypass conduits are not available, have prompted us to evaluate alternative arterial bypass conduits. The right gastroepiploic artery has been used as a coronary bypass graft in 36 patients (32 men), whose ages ranged from 29 to 71 years. Twenty-two patients had had previous coronary bypass grafting and six of these were undergoing their third bypass operation. The right gastroepiploic artery was used as an in situ graft to the right coronary artery or circumflex branches for 17 patients and as an aorta-coronary ("free") graft in 19 patients, six to the left anterior descending or diagonal, six to the circumflex, and seven to the right coronary artery. In conjunction with right gastroepiploic artery grafting, 16 patients received bilateral internal mammary artery grafts and 17 received one internal mammary artery graft. Histologically, right gastroepiploic artery segments from 18 patients could not be distinguished from internal mammary artery segments, and no evidence of atherosclerosis was found. Two patients died in the hospital, one intraoperatively and one 3 months after the operation, of a perioperative stroke. Perioperative morbidity included wound complication in three and reexploration for bleeding in two. At late follow-up 1 to 38 months after operation, two late deaths had occurred and 21 patients were free of symptoms. Postoperative angiography (postoperative interval 1 week to 13 months) was performed in nine grafts, three in situ grafts to the right coronary artery and six free grafts that included two to the left anterior descending, three to the circumflex, and one to the right coronary artery. All right gastroepiploic artery grafts were patient. The right gastroepiploic artery is an arterial conduit that can be used as an in situ graft to posterior coronary vessels and as a free graft to any coronary arterial system. Early graft patency has been excellent, and the histologic similarity between the right gastroepiploic artery and the internal mammary artery suggest that the long-term results will be favorable.

Three hundred consecutive patients received coronary arterial bypass grafts as treatment for stenosis of the left main coronary artery. Ostial stenosis was more prevalent among women (P less than 0.001). Operative (hospital) mortality was 4 percent (12 of 300). Among 148 survivors who underwent recatheterization after a mean interval of 16.5 months, the graft patency rate was 88 percent. After a minimal follow-up period of 49 months and a mean interval of 69 months, 75 percent of the survivors were asymptomatic and 94 percent were employed or fully active. The actuarial 5 year survival rate was 88.2 percent. The presence of right coronary artery disease, abnormal preoperative ventricular function and incomplete revascularization adversely affected survival, but the differences did not reach statistical significance. Comparison of this long-term follow-up study with controlled and noncontrolled studies of nonsurgical treatment of obstructions of the left main coronary artery indicates that myocardial revascularization alleviates cardiac symptoms and increases life expectancy in patients with severe atherosclerosis of this artery.

Patients with multivessel coronary atherosclerosis and stable angina pectoris were examined by outpatient testing and admitted to a staging area with their families on the morning of coronary bypass surgery. This experimental group was not hospitalized before surgery. Their hospital charges were compared with those of cohorts of coronary artery surgery patients from 1977 to 1981 who met the same entrance criteria. Length of stay in the hospital was reduced by two days. A 10% savings in hospital charges was realized in the 1981 experimental group as compared with the 1981 control group. A comparison of total hospital charges, adjusted for inflation, shows that 1981 experimental group patients paid 35% less for their hospital room, 45% less for their intensive care period, and 17% less in total charges than the 1977 control group. Interviews indicated that these patients with stable cardiac conditions preferred to stay with their families or friends before surgery.

A surgical experience with 2,445 consecutive women who underwent isolated bypass grafting was analyzed for comparison with 18,079 consecutive men. Severe or unstable angina occurred preoperatively in 60% of women and 45% of men (p less than 0.001). Despite less three vessel disease (44 versus 56%, p less than 0.001) and better left ventricular contraction (normal in 60% of women and 53% of men [p less than 0.001]), women had a higher operative mortality rate (2.9 versus 1.3%). When matched for age, severity of angina and extent of coronary atherosclerosis, women still had twice the operative mortality of men. In matched patients, body surface area was the strongest predictor of operative risk, even when the model was adjusted for gender. When the model was adjusted for body surface area, gender was not an important predictor of operative death. The smaller size of women, rather than their sex, appears to explain the difference in operative mortality. After a mean interval of 2 years, women had a lower overall graft patency rate (76.4%) than men (82.1%) (p less than 0.001). At 5 and 10 years postoperatively, a higher percent of men were angina-free. Yet, survival for women (90.6%) and for men (93.0%) at 5 years, and at 10 years (78.6 and 78.2%, respectively) was not dissimilar.

A consecutive series of 100 patients receiving left internal mammary artery grafts and a consecutive series of 100 patients receiving saphenous vein grafts as treatment of isolated left anterior descending coronary artery stenosis were reviewed to determine survival, graft patency, disease progression and New York Heart Association functional class. The mean follow-up was 67 months, and the mean catheterization interval was 20 months. Recommendations for revascularization can be made selectively to patients with critical isolated left anterior descending stenoses who have limiting symptoms and large areas of viable myocardium at risk.

Using a commercially produced lung water computer, we measured extravascular thermal volume (ETVL) to study changes in extravascular lung water (EVLW) caused by coronary artery bypass surgery. The normal baseline ETVL before anesthesia was 5.47 +/- 1.67 (SD) ml/kg. ETVL was not significantly changed 2 h after surgery but was significantly lower (P less than 0.05) 24 h later in 9 patients. There was no relationship between P(A-a)O2/FIO2 ratios and values of ETV1.

Serial arteriograms were obtained in 501 patients after coronary bypass grafting. Study I within 5 years of operation (mean interval 15 months) and Study II more than 5 years after (mean interval 88 months, range 60 to 147 months). One hundred patients received both internal mammary artery and saphenous vein grafts: 37, mammary artery grafts only, and 364, vein grafts only. In Study I, 645 (82%) of 786 vein grafts were patent, 42 (5%) stenotic or irregular, and 99 (13%) occluded. Of 140 mammary artery grafts, 136 (97%) were patent, two (2%) stenotic, and two (2%) occluded. Of the 645 vein grafts patent in Study I, 357 (55%) remained patent in Study II, 119 (18%) were stenotic or irregular, and 169 (26%) were occluded. Of 136 mammary artery grafts patent in Study I, 130 (96%) were unchanged, one was stenotic, and five (4%) were occluded in Study II. Early vein graft patency was influenced by the coronary artery grafted and by angina. Progression of vein grafts patent at Study I to stenosis or occlusion at Study II was associated with increasing postoperative interval (p less than 0.00001), interval myocardial infarction (p less than 0.001), angina (p less than 0.001), diabetes (p less than 0.004), hypercholesterolemia (p less than 0.006), and hypertriglyceridemia (p less than 0.02); it was not influenced by the coronary artery grafted. Within 5 years of operation, mammary artery graft patency exceeded vein graft patency. Between 5 and 12 years after operation, the attrition rate of vein grafts greatly exceeded that of mammary artery grafts (p less than 0.0001).

The records of the first 500 patients (420 men, 80 women, mean age 55 years, range 24 to 78) undergoing bilateral internal mammary artery (IMA) grafting were reviewed to determine in-hospital morbidity and mortality. Sixty patients (12%) had had previous cardiac operations and 130 (26%) previous saphenous vein removal. From two to seven total grafts (mean 3.2) were performed, including 595 IMA grafts to the anterior descending or diagonal artery, 355 to the circumflex, and 105 to the right coronary system. To assess changing risks, the first 125 patients (group A, 1971 to 1982) were compared with the next 375 (group B, 1982 to 1984). Major complications in groups A and B included stroke, four (3.2%) vs ine (2.4%); wound complications requiring reoperation, three (2.4%) vs five (1.3%); prolonged (greater than 48 hr) respiratory care, seven (5.6%) vs 19 (5.1%); and death, two (1.6%) vs five (1.3%) (no p value less than .05). Complications significantly less frequent in group B were new Q waves in nine (7.2%) vs 10 (2.7%) in group A (p = .02) and reoperation for bleeding in 17 (13.6%) vs 16 (4.3%) in group A (p = .0003). Logistic regression analysis showed that major complications did not correlate with gender, diabetes, number of grafts, or preoperative left ventricular function but were associated with increasing age (p = .0001) and previous cardiac surgery (p = .009) and were decreased by the use of cardioplegia (p = .002). The excellent long-term patency of IMA grafts, combined with low and decreasing perioperative risk, supports the continued use of bilateral IMA grafting.

Free internal mammary artery grafts were placed in 156 patients (1971 to 1985). Preoperative clinical and angiographic variables were similar to those of other series of isolated coronary bypass grafts. Of 244 total internal mammary artery grafts, 166 were in the aorta-coronary position and were performed mainly because of unsuitable saphenous veins or to gain additional graft length. One patient (0.6%) died during hospitalization. Perioperative complications included respiratory dysfunction in 16 (10.3%), reoperation for bleeding in 13 (8.0%), stroke in four (2.6%), myocardial infarction in three (1.9%), and wound complications in two (1.3%). Morbidity occurred significantly more often in the 1971 to 1975 period. Subsequently, eight (7%) had reoperation (6 to 158 months; mean 99 months). After a 98 month mean follow-up, the 10 year actuarial survival rate (including all causes of death) was 73.3%. Of 40 free grafts restudied within 18 months of operation, 31 (77%) were patent. The higher rate of early closure is attributed to technical problems early in our experience, especially construction of the aortic anastomosis. However, 32 of 35 (91%) free grafts studied after more than 18 months (mean 94 months) were open. Fifty of 58 (86%) free internal mammary artery grafts placed to the anterior descending coronary artery, seven of nine (78%) to the circumflex, and six of eight (75.0%) to the right coronary artery were patent. Sequential catheterization showed that of 24 free grafts open at 9 months, 24 remained patent at 80 months; when six of these were restudied at 93 months (third catheterization) and two (fourth catheterization) at 125 months, all were patent. These late studies of free internal mammary artery grafts showed no evidence of graft atherosclerosis. Free internal mammary artery grafts, like in situ internal mammary artery grafts, appear to have relative immunity from atherosclerosis. These findings expand the versatility of internal mammary artery grafting and justify wider use of free internal mammary artery grafts.

Fifteen hundred consecutive patients undergoing a first reoperation for coronary revascularization were reviewed to determine early and late results and predictors of survival. Patients were subdivided into cohorts on the basis of the year of reoperation: Group A (1967 to 1978, 436 patients); Group B (1979 to 1981, 439 patients); and Group C (1982 to 1984, 625 patients). Overall operative mortality was 3.4% (51 deaths): 4.6%, 2.3%, and 3.4% for Groups A, B, and C, respectively. Group C had significantly more women (p = 0.01) and patients with triple-vessel disease, left main coronary artery stenosis (greater than or equal to 50%), abnormal left ventricular function, age greater than or equal to 70 years, and graft failure as a surgical indication (all p less than 0.001). The mean interval between operations increased from 50 months for Group A to 84 months for Group C. At reoperation, Group C patients received more grafts, more internal mammary artery grafts, and had a higher prevalence of complete revascularization (all p less than 0.001). Univariate and multivariate analyses identified left main stenosis (p less than 0.0001), Class III or IV symptoms (p = 0.0002), advanced age (p = 0.0006), Group A (p = 0.02), and incomplete revascularization (p = 0.004) as predictors of increased in-hospital mortality. Follow-up of in-hospital survivors (mean interval 54 months, range 13 to 171 months) documented a 5 year survival rate of 90% and a 10 year survival rate of 75%. Multivariate testing identified advanced age (p less than 0.0001), hypertension (p less than 0.0001), and abnormal left ventricular function (p less than 0.0001) as predictors of decreased late survival.

Among 500 patients consecutively undergoing primary aortic valve replacement combined with coronary bypass grafting from 1967 to 1981, there were 29 (5.8%) perioperative deaths. Follow-up of the late survivors ranged from 43 to 181 months (mean 85 months); actuarial survival rates were 88%, 77%, and 52% and event-free survival rates were 80%, 65%, and 32% at 2, 5, and 10 postoperative years. Cox proportional hazard analyses were used to identify determinants of late risk. Patient-related variables associated with decreased late survival rates included advanced age, cardiothoracic ratio 50% or greater, and preoperative New York Heart Association class III or IV symptoms. Moderate or severe impairment of left ventricular function as determined by angiography and advanced age were variables that decreased late event-free survival rates. Patients with bioprostheses had better survival rates (p less than 0.001) and event-free survival rates (p = 0.012) than did patients with mechanical valves. Analyses of subgroups according to the type of valve and postoperative anticoagulant management showed that both survival and event-free survival rates were decreased for patients with mechanical valves who were not taking warfarin and were enhanced for patients with bioprostheses who were not taking warfarin.

Among 421 patients undergoing coronary artery bypass graft surgery, 55 (13%) developed 63 new peripheral nervous system (PNS) complications postoperatively. Most common was a brachial radiculoplexopathy, which occurred in 23 patients. Of these, 21 involved lower trunk or medial cord fibers. In 17 there was a correlation between the site of jugular vein cannulation and the side affected, suggesting that needle trauma played a role. Stretching from chest wall retraction may have caused some cases. Other deficits included 13 saphenous, 8 common peroneal, and 5 ulnar mononeuropathies. Six patients had persistent singultus, suggesting phrenic nerve involvement. Unilateral vocal cord paralysis was found in 5. An isolated partial Horner syndrome and a facial neuropathy were also identified. Males were more likely to develop PNS complications. Hypothermia during surgery was associated with increased risk. Most PNS deficits were transient, and lasting disability was rare.

From 1967 to 1981, 294 patients (group A) with aortic stenosis and coronary atherosclerosis underwent aortic valve replacement (AVR) combined with bypass grafting; there were 13 (4.4%) in-hospital deaths. Follow-up of the in-hospital survivors documented late survival of 89%, 79%, and 52% at 2, 5, and 10 postoperative years, respectively. Univariate and multivariate testing identified age greater than or equal to 70 years (P = 0.02) and Class IV symptoms (P = 0.002) as factors decreasing late survival. Patients with bioprostheses who did not take warfarin had the best late survival (P = 0.03) and event-free survival (P = 0.05) and patients with mechanical prostheses who did not take warfarin had the worst (P less than 0.0001) (P = 0.001). From 1981 to 1986, 375 further patients (group B) with aortic stenosis and coronary artery disease underwent AVR and bypass grafting with 20 (5.3%) in-hospital deaths. Group B contained more patients greater than or equal to 70 years (35% vs. 16%) than did group A. Logistic regression analysis identified patients with moderate or severe impairment of left ventricular function and women as sub-groups with increased in-hospital mortality in group B. Patients with aortic stenosis and coronary artery disease can undergo AVR and bypass grafting with a risk slightly increased over that for isolated AVR. Bioprostheses enhance late survival and event-free survival.

As the population of patients having undergone myocardial revascularization increases, the number of reoperations will escalate and reoperations of patients with patent grafts will become increasingly frequent. Successful management of this new surgical entity requires a clear understanding of the probability of atherosclerotic involvement of patent vein grafts and careful attention to technical detail. Patent vein grafts more than five years old should be replaced to avoid the potential for embolization of atheromatous material and late vein graft closure.

A prospective analysis of 421 patients undergoing coronary artery bypass graft (CABG) surgery as the sole cardiac procedure was carried out to assess the frequency of central nervous system (CNS) complications. In all, 451 variables were assessed in each patient. Stroke occurred in 5.2% but was severe in only 2%. Prolonged encephalopathy occurred in 11.6% but usually resolved before discharge. No statistically significant pre- or intraoperative risk variables for CNS complications were found; specifically, age or pump times in excess of two hours were not significant factors. Postoperative use of an intraaortic balloon pump and pressor agents were significantly correlated with prolonged encephalopathy. The frequency of CNS injury in CABG surgery is similar to that in other forms of open heart surgery, and there has been little change in the frequency of CNS complications over the past seven years. Possible mechanisms of CNS damage during CABG surgery are discussed.