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This retrospective study compared clinical outcomes and resource utilization in patients having off-pump coronary artery bypass grafting (OPCAB) versus conventional coronary artery bypass grafting (CABG). Angiographic patency was documented in the OPCAB group.From April 1997 through November 1999, OPCAB was performed in 200 consecutive patients, and the results were compared with those in a contemporaneous matched control group of 1,000 patients undergoing CABG. Patients were matched according to age, sex, preexisting disease (renal failure, diabetes, pulmonary disease, stroke, hypertension, peripheral vascular disease, previous myocardial infarction, and primary or redo status. Follow-up in the OPCAB patients was 93% and averaged 13.4 months.Hospital death (1.0%), postoperative stroke (1.5%), myocardial infarction (1.0%), and re-entry for bleeding (1.5%) occurred infrequently in the OPCAB group. There were reductions in the rates of transfusion (33.0% versus 70.0%; p0.001) and deep sternal wound infection (0% versus 2.2%; p = 0.067) in the OPCAB group compared with the CABG group. Angiographic assessment of 421 grafted arteries was performed in 167 OPCAB patients (83.5%) prior to hospital discharge. All but five were patent (98.8%) (93.3% FitzGibbon A, 5.5% FitzGibbon B, 1.2% FitzGibbon O). All 163 internal mammary artery grafts were patent. Off-pump coronary artery bypass grafting reduced postoperative hospital stay from 5.7 +/- 5.3 days in the CABG group to 3.9 +/- 2.6 days (p0.001), with a decrease in hospital cost of 15.0% (p0.001).Off-pump coronary artery bypass grafting reduces hospital cost, postoperative length of stay, and morbidity compared with CABG on cardiopulmonary bypass. Off-pump coronary bypass grafting is safe, cost effective, and associated with excellent graft patency and clinical outcomes.

Background . Outcomes and resource utilization of patients undergoing mitral valve replacement (MVR) with or without concomitant coronary artery bypass grafting (CABG) were reviewed. Methods . Data for 1,844 patients undergoing isolated primary MVR at Emory University Hospitals between 1980 and 1997 were recorded prospectively in a computerized database. Results . The four groups included patients undergoing elective MVR with (n = 360) or without CABG (n = 1332) and urgent/emergent MVR with (n = 66) or without CABG (n = 86). Length of stay was significantly higher in patients undergoing elective MVR with CABG (15 days) than in those without CABG (11 days) but was not significantly different in patients undergoing urgent/emergent MVR with CABG (17 days) than in those without CABG (19 days). In-hospital mortality was significantly higher for patients undergoing elective (14%) or urgent/emergent (41%) MVR with CABG than in those undergoing MVR without CABG (elective:6%; urgent/emergent:20%). The 19-year survival rate was 32% for patients undergoing elective MVR with CABG compared with 51% for those without CABG and 28% for patients undergoing urgent/emergent MVR with CABG compared with 46% for those without CABG. Multivariate correlates of long-term mortality included older age, concomitant CABG, and urgent/emergent status. Hospital costs were significantly higher for patients undergoing elective MVR with ($33,216) than for those without ($23,890) CABG. No significant difference in cost were noted between patients undergoing urgent/emergent MVR with ($40,535) and without ($31,981) CABG. Conclusions . The addition of CABG or urgent/emergent status to patients undergoing MVR significantly increases morbidity, mortality, and costs. Careful scrutiny of the benefits versus resource utilization is required for patients undergoing high risk MVR.

Background . The purpose of this study was to determine whether or not endoscopic vein harvest is a reliable, beneficial, and cost-effective method for saphenous vein harvest in coronary bypass surgery (CABG). Methods . A total of 100 patients having primary CABG were prospectively randomized to either endoscopic (EVH; n=47) or open saphenous vein harvest (OVH; n=50). Three patients in the EVH group required both techniques and were excluded from analysis. Results . The groups did not differ in preoperative characteristics, including: age, gender, left ventricular function, height, weight, percent over ideal body weight, incidence of diabetes, peripheral vascular disease, or preoperative laboratory values (creatinine, albumin, or hematocrit). The EVH group had longer vein harvest and preparation times than the OVH group, while the incision length was significantly shorter. There was no difference between groups in mortality, perioperative myocardial infarction, intensive care unit or postopera-tive length of stay, blood product utilization, or discharge laboratory measures. There was more drainage noted from leg incisions at hospital discharge in the OVH (34%) versus EVH group (8%; p = 0.001), but more ecchymosis in the EVH group. Although there was a trend towards reduced leg incision pain in the EVH group, there was no statistically significant difference in pain or in the quality of life measure at any point in time. There was no difference between groups in readmission to hospital, administration of antibiotics, or incidence of leg infection. While mean hospital charges for the EVH group were approximately $1,500 greater than for OVH, this difference did not reach statistical significance. Conclusions . EVH is a safe, reliable, and cost-neutral method for saphenous vein harvest. The best indication for EVH may be in patients who are at increased risk for wound infection and in those for whom cosmesis is a major concern.

The American College of Cardiology/American Heart Association (ACC/AHA) Task Force on Practice Guidelines was formed to make recommendations regarding the appropriate use of diagnostic tests and therapies for patients with known or suspected cardiovascular disease. Coronary artery bypass graft (CABG) surgery is among the most common operations performed in the world and accounts for more resources expended in cardiovascular medicine than any other single procedure. Since the original Guidelines were published in 1991, there has been considerable evolution in the surgical approach to coronary disease, and at the same time there have been advances in preventive, medical, and percutaneous catheter approaches to therapy. These revised guidelines are based on a computerized search of the English literature since 1989, a manual search of final articles, and expert opinion. As with other ACC/AHA guidelines, this document uses ACC/AHA classifications I, II, and III as summarized below: Class I: Conditions for which there is evidence and/or general agreement that a given procedure or treatment is useful and effective. Class II: Conditions for which there is conflicting evidence and/or a divergence of opinion about the usefulness or efficacy of a procedure. Class IIa: Weight of evidence/opinion is in favor of usefulness/efficacy. Class IIb: Usefulness/efficacy is less well established by evidence/opinion. Class III: Conditions for which there is evidence and/or general agreement that the procedure/treatment is not useful/effective and in some cases may be harmful. ### A. Hospital Outcomes Seven core variables (priority of operation, age, prior heart surgery, sex, left ventricular [LV] ejection fraction [EF], percent stenosis of the left main coronary artery, and number of major coronary arteries with significant stenoses) are the most consistent predictors of mortality after coronary artery surgery. The greatest risk is correlated with the urgency of operation, advanced age, and 1 or more prior coronary bypass surgeries. Additional variables that are related …

Background . In an attempt to avoid the deleterious effects of cardiopulmonary bypass, off-pump coronary artery bypass grafting has been rediscovered and refined. The purpose of this study was to compare clinical outcomes, length of stay, and hospital costs with coronary artery bypass grafting on cardiopulmonary bypass. Methods . Coronary artery bypass was performed on 51 patients without cardiopulmonary bypass. Patients were selected on the basis of coronary anatomy, with significant stenoses in the left anterior descending, ramus intermedius, diagonal, right coronary, acute marginal, or posterior descending territories. Outcomes were compared with those of a computer-generated matched control group having coronary artery bypass grafting on cardiopulmonary bypass (n = 248) during the same time period. Results . No preoperative differences were noted between groups. There were no deaths in the off-pump group and a mortality rate of 1.6% (4/248) in the control group. There was no incidence of stroke, myocardial infarction, or reentry for bleeding among patients in the off-pump group. There was a reduction in length of stay by 3 days ( p = 0.01), blood transfusions by 50% ( p = 0.0001), and hospital charges by one third ( p = 0.05) in the off-pump group. Twenty-six patients had repeat coronary angiography before discharge; 41/43 grafts were widely patent, 1/43 was totally occluded, and 1/43 was narrowed by more than 50%. All internal mammary artery grafts were widely patent. Conclusions . Off-pump multivessel cardiopulmonary bypass grafting is a safe and effective means of revascularization for patients with coronary stenoses in the anterior or inferior regions, with excellent short-term patency rates and minimal morbidity.

Background Previous studies have demonstrated increased risk in patients undergoing coronary artery bypass surgery (CABG), but the effect of this increasing risk on outcomes has not been well documented. The purposes of this study were (1) to evaluate patients who had CABG from 1993 to 1995 (group III) and compare them with patients from 1981 through 1987 (group I) and 1988 through 1992 (group II) to determine if the trend toward higher-risk patients continued and (2) to evaluate what effect risk had on in-hospital outcomes. Methods and Results Data were collected prospectively on patients undergoing CABG. Patients from the three time periods were compared by use of univariate and multivariate statistics. Risk models for mortality were developed by use of logistic regression. Significant changes were noted in the three time periods, with risk increasing over time. Increased risk was associated with increased mortality in group II, but mortality declined in group III despite the continued increase in patient risk. Group II had an increase in complications, with little change in group III. The actual mortality rate was lower than predicted in group III. Conclusions Patients undergoing CABG are increasingly high risk. In-hospital mortality rates declined during the period from 1993 through 1995 and were lower than predicted despite the increase in risk. This decreased mortality rate may reflect greater experience in providing care to high-risk patients and improved myocardial protection and surgical and anesthetic techniques. Although continued analysis of patient risk and benefit is needed, researchers must be cognizant of the rapid changes in technology and knowledge and should correlate changes in the process of care with outcomes.

The coronary microvascular system is important in the regulation of myocardial perfusion. Preservation of microvascular reactivity may be important in those hearts undergoing ischemic storage for transplantation. Endothelium-dependent relaxation of right and left ventricular coronary microvessels was examined in a canine model of heart transplantation.Canine hearts underwent topical cooling, antegrade arrest, and 3 hours' ischemic cold storage at 4 degrees C using crystalloid cardioplegia (n = 8), Roe's solution (n = 8), and University of Wisconsin solution (n = 8). All groups underwent 1 hour of reperfusion in an isolated heart circuit. Noninstrumented canines were used as controls (n = 10). Coronary microvessels (100 to 200 microns in diameter) were examined in a pressurized, no-flow state with video microscopic imaging and electronic dimension analysis.Endothelium-dependent microvascular relaxation was examined in response to the receptor-dependent acetylcholine and to the receptor-independent calcium ionophore. Microvascular relaxation to acetylcholine in Roe's solution and University of Wisconsin solution was preserved (p = not significant) in the left ventricle, whereas crystalloid cardioplegia failed to preserve (p0.05) microvascular relaxation when compared with the control groups. Right ventricular microvascular relaxation was always (p0.05) less than left ventricular microvascular relaxation. Endothelium-independent microvascular relaxation to nitroprusside was similar to that in controls, indicating normal smooth muscle responsiveness.Ischemic cold storage with Roe's solution and University of Wisconsin solution preserved microvascular relaxation in the left ventricle, whereas crystalloid cardioplegia failed to preserve microvascular relaxation. Right ventricular microvascular relaxation was impaired in all groups, but University of Wisconsin solution was superior to crystalloid cardioplegia and Roe's solution. This suggests that microvascular dysfunction may be partially responsible for right ventricular dysfunction after heart transplantation. The choice of preservation solution may be important in preservation of the microvascular endothelium.

Several studies suggest that normothermic (“warm”) bypass techniques may improve myocardial outcomes for patients undergoing cardiac operations. Normothermic temperatures during cardiopulmonary bypass may, however, decrease the brain's tolerance to the ischemic insults that accompany all cardiac procedures. To assess the effect of bypass temperature management strategy on central nervous system outcomes in patients undergoing coronary revascularization, 138 patients were randomly assigned to two treatment groups: (1) hypothermia ( n = 70), patients cooled to a temperature less than 28º C during cardiopulmonary bypass, or (2) normothermia ( n = 68), patients actively warmed to a temperature of at least 35º C. Patients underwent detailed neurologic examination before the operation, on postoperative days 1 to 3 and 7 to 10, and at approximately 1 month after operation. In addition, a battery of five neuropsychologic tests was administered before operation, on postoperative days 7 to 10, and at the 4- to 6-week follow-up visit. Patients in the normothermic treatment group were older (65 ± 10 vs 61 ± 11 years in the hypothermic group), had statistically less likelihood of preexisting cerebrovascular disease, and had higher bypass blood glucose values (276 ± 100 mg/% vs . 152 ± 66 mg/% in the hypothermic group). All other patient characteristics and intraoperative variables were similar in the two treatment groups. Seven of 68 patients in the normothermic group were found to have a central neurologic deficit, compared with none of the patients cooled to 28º C ( p = 0.006). Performance on at least one neuropsychologic test deteriorated in the immediate postoperative period in more than one half of all patients in both treatment groups but returned to preoperative levels approximately 1 month after the operation in most (85%). This pattern was not related to bypass temperature management strategy. We conclude that active warming during cardiopulmonary bypass to maintain systemic temperatures ≥35º C increases the risk of perioperative neurologic deficit in patients undergoing elective coronary revascularization. (J T horac C ardiovasc S urg 1996;112:514-22)

Background. Intracoronary stents are being used to treat acute and threatened closure after percutaneous transluminal coronary angioplasty and to prevent restenosis. Methods. The outcomes of 68 patients having coronary artery bypass grafting after stent placement were reviewed. The mean age was 60.5 ± 9.7 years, and 71% were male. Thirty-seven percent had hypertension, 13% had diabetes, 62% had class III or IV angina, 60% had multivessel disease, and 40% had sustained a prior myocardial infarction. Fifty-three patients underwent emergency operation, 22 with hemodynamic collapse immediately after percutaneous transluminal coronary angioplasty, and 7 others required urgent revascularization within 24 hours of angioplasty. Seventeen underwent coronary artery bypass grafting for acute closure of the stented vessel several days after the angioplasty procedure. Results. There was no correlation between urgency of the procedure, previous infarction, or previous coronary artery bypass grafting with successful procedure. The in-hospital mortality was 4.4%, 21% had a Q-wave myocardial infarction, and 1.5% sustained a stroke. Ejection fraction was the only correlate of long-term mortality. Conclusions. Coronary artery injury for which stents are placed for acute or threatened occlusion or to prevent restenosis but then fail, thus necessitating coronary artery bypass grafting, can be treated successfully. Although the rate of Q-wave myocardial infarction is substantial and related to the initial ischemic insult, the long-term survival and event rates are excellent with prompt surgical revascularization.

From March 1991 through July 1992, 1,001 patients having elective coronary artery bypass grafting were randomized to receive either continuous warm (> or = 35 degrees C) blood cardioplegia with systemic normothermia (> or = 35 degrees C) or intermittent cold ( or = 3 in-hospital days) stroke (warm, 5 patients, and cold, 1 patient). All patients experiencing a stroke had a persistent neurologic deficit at the time of discharge. Encephalopathy resolved completely in all instances.(ABSTRACT TRUNCATED AT 250 WORDS)

Continuous retrograde warm blood cardioplegia was compared with two widely used hypothermic myocardial protection techniques in a canine model of acute regional myocardial ischemia with subsequent revascularization. Animals (n = 30) underwent 45 minutes of left anterior descending coronary artery occlusion then cardioplegic arrest (60 minutes), followed by separation from cardiopulmonary bypass and data collection. The cold oxygenated crystalloid cardioplegia group (CC; n = 8) and the cold blood cardioplegia group (CC; n = 10) had cardiopulmonary bypass at 28 degrees C, antegrade arrest, and intermittent retrograde delivery. The warm blood cardioplegia group (WB; n = 12) had normothermic cardiopulmonary bypass, antegrade arrest, and continuous retrograde delivery. Overall ventricular function (preload recruitable stroke work relationship; ergs x 10(3)/mL) was significantly (p0.001) better for WB (WB, 80 +/- 11; CB, 67 +/- 13; CC, 57 +/- 12). Systolic function (maximum elastance relationship; mm Hg/mL) was also significantly (p0.001) better for WB (WB, 11.6 +/- 3.6; CB, 8.6 +/- 2.7; CC, 6.2 +/- 1.3). Diastolic function (stress-strain relationship; dynes x 10(3)/cm2) revealed significantly (p0.001) decreased compliance for CC (WB, 20 +/- 6; CB, 19 +/- 7; CC, 27 +/- 11). Left anterior descending coronary artery regional adenosine triphosphate/adenosine diphosphate ratios were significantly (p = 0.02) worse for CC (WB, 10.2 +/- 2.3; CB, 9.4 +/- 2.6; CC, 5.6 +/- 1.5). Myocardial edema significantly (p = 0.03) increased over time only in the CC animals (WB, 0.4% +/- 2.3%; CB, -0.3% +/- 3.6%; CC, 5.5% +/- 2.3%). In this model of acute regional myocardial ischemia and revascularization, continuous retrograde warm aerobic blood cardioplegia provided superior myocardial protection compared with cold oxygenated crystalloid cardioplegia with intermediate results for cold blood cardioplegia.

Despite distinct advantages over mechanical cardiac valve prostheses, the use of bioprosthetic valves remains limited due to poor long-term durability, primarily as a result of tissue calcification. A novel anticalcification process, based on treatment of porcine bioprostheses with a derivative of oleic acid, has been developed by one of us (J.M.G.) (US Patent Number 4,976,733). This process employing 2-aminooleic acid (AOA) was tested in a juvenile sheep model. Terminal studies after a 20-week interval included hemodynamic, radiographic, morphologic, and quantitative tissue calcium analyses. All control valves (n = 4) had thickened, immobile, heavily calcified leaflets, whereas all AOA-treated valves (n = 8) were pliable and free of calcium deposits. Calculated valve orifice areas for controls (0.9 +/- 0.2 cm2) (mean +/- standard error of the mean) was less than for AOA-treated valves (2.0 +/- 0.3 cm2) (p less than 0.05). Radiographic calcification scores were greatly elevated in the control (25.5 +/- 5.6) versus AOA-treated valves (0.5 +/- 0.5) (p less than 0.002). In quantitative mineralization studies, the mean calcium content of the control leaflets was 129 +/- 21 milligrams per gram dry weight cusp tissue versus 7.7 +/- 5.8 mg/g for AOA-treated valves (p less than 0.001). Pathologic examination confirmed heavy calcification in the control leaflets, which was essentially absent in the AOA-treated leaflets. However, cuspal hematomas in areas of structural loosening and surface roughening were noted in AOA-treated valves. This anticalcification process dramatically reduced mineralization of porcine valve prostheses in this model.

Intraoperative dissection and late ascending aortic dissection and aneurysm formation infrequently complicate cardiac operations but remain a significant source of morbidity and mortality. A review of 11,145 consecutive cardiac operations at Emory University from January, 1982 through December, 1988 yielded 27 patients with an intraoperative ascending aortic dissection (incidence 0.24%) occurring at the time of the original procedure, with a hospital mortality of 14.8%. Nine additional patients with ascending aortic dissection or aneurysm, presenting late after a previous cardiac operation, were treated during this same period with three deaths. The technical aspects and decision making for application of closed aortic plication, open aortic reconstruction, and ascending aortic replacement based directly on the extent of the intraoperative dissection is detailed. An individualized technical approach tailored to the pathology encountered is outlined for the reoperative group of patients. Etiology, risk factors, principles of prevention, and indications for operation are also discussed.

Performance of bioprosthetic valves is limited by tissue degeneration due to calcification with reduced performance and longevity. The Mosaic bioprosthetic valve (Medtronic Heart Valves, Inc, Minneapolis, MN) combines zero pressure fixation, antimineralization properties of alpha-amino oleic acid (AOA), and a proven stent design. We tested the hypothesis that AOA treatment of Mosaic valves improves hemodynamics, antimineralization properties, and survival in a chronic ovine model.Mitral valves were implanted in juvenile sheep with Mosaic valves with AOA treatment (n = 8) or without AOA treatment (non-AOA, n = 8), or Hancock I (HAN, n = 4) tissue valves, and explanted at 20 postoperative weeks.Survival was equivalent in AOA and non-AOA (140 +/- 0.4 and 129 +/- 30 days), but was significantly less in HAN (82 +/- 35). Leaflet calcium (microgCa/mg tissue) was less in AOA (9.6 +/- 13.9; p0.05 versus non-AOA and HAN) than non-AOA (96.3 +/- 63.8) and HAN (130.8 +/- 43.2). Explant valve orifice area (cm2) was significantly preserved in the AOA group compared with the non-AOA group (1.5 +/- 0.7 vs 0.8 +/- 0.3; p0.05 versus non-AOA and HAN).We conclude that AOA treatment of Mosaic valves reduces leaflet calcification and valve gradient in juvenile sheep, and that the Mosaic design and fixation features may offer survival advantages that must be confirmed in extended trials.

Stroke is a major complication of coronary operation, with reported rates of postoperative cerebral dysfunction ranging from 0.4% to 13.8%. In this report, the incidence, correlates, outcomes, and costs of stroke in coronary operation were evaluated at Emory University between 1988 and 1996.Data were entered prospectively into a dedicated computerized database at Emory University and analyzed retrospectively. Univariate and multivariate analyses were utilized where appropriate.Data from 10,860 patients undergoing primary coronary operation between 1988 and 1996 were analyzed. There were 250 patients not entered into the database. Stroke occurred in 244 (2.2%). Univariate predictors of stroke (p0.05) included age, female gender, hypertension, diabetes, prior stroke, prior transient ischemic attack (TIA), and carotid bruits. Multivariate correlates included age (odds ratio 1.07) previous TIA (odds ratio 2.2), and carotid bruits (odds ratio 1.9), although the area under the Receiver Operating Characteristics (ROC) curve was only 0.69, suggesting limited ability to predict stroke. One and 5 year survival rates were 64% and 44% with stroke, and 94% and 81% without stroke, respectively. Among the stroke group, 23% of the patient population died before hospital discharge. The stroke group had a significantly longer length of hospital stay, as well as higher costs.Stroke is a devastating complication of coronary operation, significantly increasing morbidity, mortality, and cost. Three independent variables were identified for predicting stroke, including age, previous TIA, and carotid bruits. Patients should be carefully screened for cerebrovascular disease to help prevent stroke and its associated morbidity.

Multiple organ failure after deep hypothermic circulatory arrest (DHCA) may occur secondary to endothelial dysfunction and apoptosis. We sought to determine if DHCA causes endothelial dysfunction and apoptosis in brain, kidney, lungs, and other tissues.Anesthetized pigs on cardiopulmonary bypass were: (1) cooled to 18 degrees C, and had their circulation arrested (60 minutes) and reperfused at 37 degrees C for 90 minutes (DHCA, n = 8); or (2) time-matched normothermic controls on bypass (CPB, n = 6). Endothelial function in cerebral, pulmonary, and renal vessels was assessed by vasorelaxation responses to endothelial-specific bradykinin (BK) or acetylcholine (ACh), and smooth muscle-specific nitroprusside.In vivo transcranial vasorelaxation responses to ACh were similar between the two groups. In small-caliber cerebral arteries, endothelial relaxation (BK) was impaired in CPB vs DHCA (maximal 55% +/- 2% [p0.05] vs 100% +/- 6%). Pulmonary artery ACh responses were comparable between CPB (110% +/- 10%) and DHCA (83% +/- 6%), but responses in pulmonary vein were impaired in DHCA (109% +/- 3%, p0.05) relative to CPB (137% +/- 6%). In renal arteries, endothelial (ACh) responses were impaired in DHCA (71% +/- 13%) relative to CPB (129% +/- 14%). Apoptosis (DNA laddering) occurred primarily in duodenal tissue, with a greater frequency in DHCA (56%, p0.05) compared with normothermic CPB (17%) and nonbypass controls (0%).DHCA is associated with endothelial dysfunction in cerebral microvessels but not in the in vivo transcranial vasculature; in addition, endothelial dysfunction was noted in large-caliber renal arteries and pulmonary veins. DHCA is also associated with duodenal apoptosis. Vascular endothelial dysfunction and apoptosis may be involved in the pathophysiology of multisystem organ failure after DHCA.

Cardiac valve replacement and coronary artery bypass graft surgery (CABG) are being applied with increasing frequency in patients 80 years of age and older.Six hundred one consecutive patients older than 80 years, undergoing cardiac surgery between 1976 and 1994 (CABG with saphenous vein graft, 329 [54.7%]; CABG with left internal mammary artery, 101 [16.8%]; CABG + valve, 80 [13.3%]; isolated aortic valve replacement, 71 [11.8%]; isolated mitral valve replacement, 18 [3.0%]), were studied retrospectively to assess short- and long-term survival. They were compared with 11,386 patients aged 60 to 69 years and 5,698 patients aged 70 to 79 years undergoing similar procedures during the same time interval.In comparison with patients 60 to 69 years old, more octogenarians were women (44.4% versus 25.6%, p0.0001), had class IV angina (54.1% versus 38.9%, p0.0001), and had congestive heart failure class IV (4.9% versus 3.0%, p = 0.0001). In-hospital death rates (9.1% versus 3.4%, p0.0001) and stroke (5.7% versus 2.6%, p0.0001) reflected these adverse clinical risk factors. However, Q-wave infarction tended to be less frequent (1.5% versus 2.6%, p = 0.102). Interestingly, hospital mortality (9.1% versus 6.7%, p = 0.028) was only slightly increased, and stroke (5.7% versus 4.7%, p = 0.286) was not more common in octogenarians than in patients 70 to 79 years old. Late-survival curves have similar slopes for the first 5 years in all clinical subgroups. However, after 5 years there is a more rapid decline in octogenarians than in younger age groups. Median 5-year survival was 55% for patients older than 80 years, 69% for patients 70 to 79 years, and 81% for patients 60 to 69 years old.When appropriately applied in selected octogenarians, cardiac surgery can be performed with acceptable mortality and excellent 5-year survival.

Background. Despite recent rediscovery of beating heart cardiac surgical techniques, extracorporeal circulation remains appropriate for most heart operations. To minimize deleterious effects of cardiopulmonary bypass, antiinflammatory strategies have evolved. Methods. Four state-of-the-art strategies were studied in a prospective, randomized, preoperatively risk stratified, 400-patient study comprising primary (n = 358), reoperative (n = 42), coronary (n = 307), valve (n = 27), ascending aortic (n = 9), and combined operations (n = 23). Groups were as follows: standard, roller pump, membrane oxygenator, methylprednisolone (n = 112); aprotinin, standard plus aprotinin (n = 109); leukocyte depletion, standard plus a leukocyte filtration strategy (n = 112); and heparin-bonded circuitry, centrifugal pumping with surface modification (n = 67). Results. Analysis of variance, linear and logistic regression, and Pearson correlation were applied. Actual mortality (2.3%) was less than half the risk stratification predicted mortality (5.7%). The treatment strategies effectively attenuated markers of the inflammatory response to extracorporeal circulation. Compared with the other groups the heparin-bonded circuit had highly significantly decreased complement activation ( p = 0.00001), leukocyte filtration blunted postpump leukocytosis ( p = 0.043), and the aprotinin group had less fibrinolysis ( p = 0.011). Primary end points, length of stay, and hospital charges, were positively correlated with operation type, age, pump time, body surface area, stroke, pulmonary sequelae, predicted risk for stroke, predicted risk for mortality, and risk strata/treatment group interaction ( p = 0.0001). In low-risk patients, leukocyte filtration reduced length of stay by 1 day ( p = 0.02) and mean charges by $2,000 to $6,000 ( p = 0.05). For high-risk patients, aprotinin reduced mean length of stay up to 10 fewer days ( p = 0.02) and mean charges by $6,000 to $48,000 ( p = 0.0007). Conclusions. These pharmacologic and mechanical strategies significantly attenuated the inflammatory response to extracorporeal circulation. This translated variably into improved patient outcomes. The increased cost of treatment was offset for selected strategies through the added value of significantly reduced risk.

Background . Tepid blood (TB) cardioplegia combines the improved rheologic characteristics and the augmented oxygen and substrate delivery of blood cardioplegia with the advantages of moderate hypothermia. In addition, the intramyocardial distribution of continuous TB cardioplegia may also be better than intermittent cold crystalloid (CC) cardioplegia. We sought to compare the distribution of TB and CC cardioplegia at varying infusion pressures. Methods . In situ, isolated canine hearts were randomized to antegrade, continuous TB (28°C, n=8) or intermittent CC (n = 8) cardioplegia infused at 50, 75, and 100 mm Hg. The regional distribution of cardioplegia at each pressure was measured by 15-μm colored microspheres. Cardioplegia distribution was measured from three areas each of the right ventricle (inflow, outflow, and apex) and the left ventricle (anterior, lateral, and posterior). Left ventricular samples were subdivided into subepicardial, midmyocardial, and subendocardial. Results . Delivery of cardioplegia to all areas of the right and left ventricles showed a linear pressure–flow relationship over the range of pressures tested. Right ventricular distribution was two-thirds of that to the left ventricle, and left ventricular subepicardial distribution was approximately one half of subendocardial flow in both groups at all delivery pressures. However, the subendocardial to subepicardial ratio was significantly greater with TB cardioplegia than with CC cardioplegia. Transmural right ventricular cardioplegia flow was comparable in both groups. In contrast, left ventricular distribution of CC cardioplegia was greater than TB cardioplegia at all three pressures tested. Conclusions . The pressure–flow relationship in both CC and TB cardioplegia is linear in both the right and left ventricular myocardium over clinically applicable delivery pressures. The distribution of cardioplegia to the right ventricle is not altered by increased pressure.

Left ventricular dysfunction is a predictor of hospital mortality after cardiac valve operation. We evaluated late survival in a large cohort of these patients.From 1980 to 1993, 257 patients with a preoperative ejection fraction of 0.40 or less underwent aortic (n = 177), mitral (n = 72), or combined (n = 8) valve operation, with or without concomitant coronary artery bypass grafting.Hospital mortality was 12.5%. Follow-up was 98% complete. Logistic regression analysis showed that an ejection fraction of less than 0.30, mitral regurgitation, concomitant coronary artery bypass grafting, emergency operation, and reoperation were independent correlates of hospital mortality (all at p0.05). Kaplan-Meier survival curves of the 220 hospital survivors showed a 65% 5-year survival. Multivariate analysis revealed preoperative use of diuretics, male sex, reoperation, age exceeding 60 years, and aortic regurgitation to be independent predictors of poor late outcome (all at p0.05).The liability of left ventricular dysfunction with regard to diminished long-term survival is not completely reversed by valve operation. If operation is not performed before left ventricular dysfunction develops, postoperative medical treatment of these dilated, remodeled ventricles should be considered.

Aminooleic acid treatment has been demonstrated to prevent porcine valve calcification and to protect valvular hemodynamic function. Initial enthusiasm was tempered by histologic studies of these AOA valves, which showed cuspal hematomas, structural loosening, and surface roughening. This prompted a systematic review of the AOA treatment process. Unsolubilized particles of alpha aminooleic acid present in the treatment solution were identified as the cause of mechanical abrasion of valve cusps during processing. These particles were eliminated with a revamped protocol, which included filtration of the AOA solution before valve preparation.Porcine aortic valve cusps treated with this modified AOA protocol (AOA II) were studied in a rat subdermal implant model of mineralization. A juvenile sheep trial was then used to confirm the antimineralization effects of AOA II on glutaraldehyde-fixed porcine aortic roots in a circulatory model of accelerated calcification.Retrieved AOA II-treated cusps from the subdermal model were markedly less calcified than control cusps (AOA II, 1 +/- 0, 17 +/- 4, 23 +/- 6, and 17 +/- 10 versus control, 189 +/- 14, 251 +/- 16, 250 +/- 14, and 265 +/- 10 mg calcium/mg sample at 4, 8, 12, and 16 weeks, respectively; p0.0001). Morphologic examination of the AOA II cusps of the valves retrieved from the sheep demonstrated freedom from the structural loosening, surface roughening, and hematoma formation that had limited the utility of the original AOA preparation technique. Cusps from AOA II-treated porcine roots had significantly less calcium than control cusps (AOA II, 5.5 +/- 3.0 mg/g; control, 91.2 +/- 19.5 mg/g; p = 0.0004). The aortic walls had similar levels of calcification (AOA II, 156 +/- 73 mg/g; control, 159 +/- 10 mg/g; p = not significant).These data suggest that the modified AOA technique warrants further evaluation as an antimineralization treatment for glutaraldehyde-fixed porcine bioprostheses.

The effects of three techniques of cardioplegic arrest on endothelium-dependent microvascular function of the right and left ventricles were examined in a canine model of cardiopulmonary bypass.Oxygenated cold crystalloid cardioplegia and cold blood cardioplegia groups, (n = 11 each) had hypothermic cardiopulmonary bypass (28 degrees C), topical cooling, antegrade arrest, and intermittent antegrade delivery. A warm blood cardioplegia group (n = 11) had normothermic cardiopulmonary bypass (37 degrees C), antegrade arrest, and continuous antegrade delivery. All groups underwent cardioplegic arrest for 1 hour followed by 1 hour of reperfusion. Dogs that did not have instrumentation were used as controls (n = 10). Coronary microvessels (100 to 200 microns in internal diameter) were examined in a pressurized, no-flow state with video microscopic imaging and electronic dimension analysis.Ischemic arrest with cold crystalloid cardioplegia significantly (p0.05) impaired endothelium-dependent relaxations in both ventricles to acetylcholine (left ventricle, 69% +/- 4%, and right ventricle, 73% +/- 5%, versus control left ventricle, 100% +/- 0.3%, and control right ventricle, 100% +/- 0.3%) and the calcium ionophore (left ventricle, 70% +/- 6%, and right ventricle, 68% +/- 3%, versus control left ventricle, 98% +/- 1%, and control right ventricle, 98% +/- 1%). In the cold blood cardioplegia group, endothelium-dependent relaxations to acetylcholine (left ventricle, 96% +/- 1%, and right ventricle, 87% +/- 4%) and the calcium ionophore (left ventricle, 88% +/- 3%, and right ventricle, 78% +/- 7%) were preserved. In the warm blood cardioplegia group, endothelium-dependent responses to acetylcholine (92% +/- 3%) and the calcium ionophore (96% +/- 1%) were preserved in the left ventricle, but the right ventricle showed reduced (p0.05) reactivity to the endothelium-dependent acetylcholine (77% +/- 8%) and the calcium ionophore (69% +/- 8%). Endothelium-independent relaxation to sodium nitroprusside was similar to controls in all groups for both ventricles, thus indicating normal smooth muscle responsiveness.Cardioplegic arrest with cold blood cardioplegia preserved the endothelium-dependent response in the right and left ventricles, whereas cold crystalloid cardioplegia impairs this response. Warm blood cardioplegia preserved the endothelium-dependent response in the left ventricle, but this response was reduced in the right ventricle. This suggests that blood cardioplegia and hypothermia may be important in protection of microvascular endothelium and that the right ventricle may be more vulnerable to damage than the left ventricle.

Cardiopulmonary bypass (CPB) predisposes cardiac surgical patients to postoperative wound infections1,2 by altering their immunologic host response and increasing their susceptibility to infection, a primary cause of morbidity and mortality following open-heart surgery. The “cost” of infection after cardiac surgery includes human suffering, hospital confinement, loss of productivity, and mortality. There can be a broad range of infectious complications postoperatively (Table 8.1). Mediastinitis, occurring in 1% to 2% of median sternotomies, has a mortality rate of 60% to 70%.3 Early and late prosthetic valvular endocarditis are associated with mortality rates of 73% and 45%, respectively,4,5 and occur in approximately 2% to 3% of valvular replacement procedures. An assessment of hospital stay following coronary artery bypass surgery demonstrated that infectious complications prolonged hospitalization fourfold, with infection representing the most important variable for increased length of stay.6 A 1990 cost assessment of cardiac surgery patients reported that median sternotomy infections produced a median hospital cost of $58,092 (range $19,966 to $408,632), almost triple the cost of an uncomplicated cardiac procedure.7

The effects of different cardioplegia temperatures on myocardial protection with continuous aerobic blood cardioplegia were studied in a canine model of acute regional injury after left anterior descending coronary artery occlusion and subsequent revascularization. Twenty-five animals underwent 90 minutes of occlusion followed by revascularization during 60 minutes of electromechanical arrest with continuous retrograde blood cardioplegia delivered at one of three temperatures: 18 degrees C (n = 8), 28 degrees C (n = 8), and 37 degrees C (n = 9). Left ventricular protection was assessed in a right heart bypass model in terms of the left ventricular pressure-volume relationships, myocardial oxygen consumption, regional myocardial blood flow, adenosine trisphosphate concentration, and water content. The preload recruitable stroke work relationship at 90 minutes after reperfusion was better in the 18 degrees C and 28 degrees C groups than that in the 37 degrees C group (18 degrees C, 85 +/- 14 erg x 10(3)/mL; 28 degrees C, 77 +/- 17 erg x 10(3)/mL; 37 degrees C, 58 +/- 13 erg x 10(3)/mL; p < 0.05). The maximum elastance and stress-strain relationships showed there were no significant differences between the groups at 90 minutes. The myocardial oxygen consumption was greatest in the 37 degrees C group during the first hour after reperfusion (18 degrees C, 5.4 +/- 1.4 mL O2.min-1.100 g-1; 28 degrees C, 4.7 +/- 1.1 mL O2.min-1.100 g-1; 37 degrees C, 6.3 +/- 1.6 mL O2.min-1.100 g-1; p < 0.05). The regional myocardial blood flow, adenosine triphosphate concentration, and myocardial water content were similar in the three groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Three myocardial protection techniques were studied in a canine model of acute myocardial ischemia with subsequent revascularization. Eighteen animals were randomly assigned to one of three treatment regimens: cold oxygenated crystalloid cardioplegia (CC), cold blood cardioplegia with modified reperfusate (CB), and continuous aerobic warm blood cardioplegia (WB) (n = 6 per group). Systemic hypothermic cardiopulmonary bypass (28 degrees C), antegrade arrest, and intermittent retrograde and antegrade delivery were used for the CC and CB groups. Systemic normothermic cardiopulmonary bypass, antegrade arrest, and continuous retrograde delivery were used for the WB group. Fifteen minutes of warm global ischemia was followed by occlusion of the left anterior descending coronary artery (15-minute duration) and simultaneous initiation of cardioplegic arrest (60-minute duration) to simulate clinical revascularization. After reperfusion, the animals were separated from cardiopulmonary bypass. Myocardial function, electrocardiogram, myocardial energetics, water content, histopathology, and defibrillation requirements were compared between groups. There was no significant difference in maximum elastance, myocardial oxygen consumption, myocardial edema, or histopathologic evidence of injury between groups. However, overall ventricular function, assessed by the slope of the preload recruitable stroke work relationship, was significantly better for the WB group (p = 0.04) (WB, 73 +/- 9; CB, 56 +/- 7; CC, 47 +/- 5). Diastolic function as assessed by the slope of the stress-strain relationship was significantly worse overall for the cold groups (p = 0.001) (WB, 20 +/- 2.2; CB, 39 +/- 1.3; CC, 37 +/- 3.1). Myocardial injury as assessed by ST segment elevation (millimeters) was less for the WB group (p = 0.03) (WB, 0.4 +/- 0.3; CB, 1.7 +/- 0.2; CC, 1.6 +/- 0.7). Countershocks necessary to restore sinus rhythm after cross-clamp removal were fewer in the WB group (p = 0.03) (WB, 0.8 +/- 0.3; CB, 4.0 +/- 1.2; CC, 5.5 +/- 1.5). In this model of acute global myocardial ischemia, continuous aerobic warm blood cardioplegia has important advantages over two widely used clinical hypothermic protection techniques.

The majority of patients who receive modern antireflux operations obtain substantial long-term relief of their symptoms. About 10% to 15% will have persistent or recurrent problems, some severe enough to warrant reoperation for correction. With careful symptom review, barium study, endoscopy, and manometry, the mechanism of failure becomes evident, and remedial surgical treatment may proceed. The results at reoperation are not as good as those of the primary procedure, which emphasizes the need for proper diagnosis and choice of procedure and for reliable execution of technique at the initial treatment.

Crystalloid cardioplegia with an extracellular fluid formulation is widely used for donor heart protection. A survey of 109 transplant programs yielded 62 replies with 42% of respondents using variations of extracellular solution and 45% using the dextrose and mannitol-based Stanford solution. These two commonly used clinical solutions and University of Wisconsin (UW) solution, which has had success in clinical hepatic and renal transplantation, were compared in a canine model of cardiac transplantation. After antegrade hypothermic cardioplegic arrest, the experimental hearts were excised and stored at 4 degrees C for 6 hours (n = 29). An oxygenated, blood-primed isolated heart preparation was used for reperfusion. After a rest of 45 minutes, cardiac output was increased against constant afterload until a left atrial pressure of 15 mm Hg was reached. The maximum cardiac performance measured by cardiac index, minute work, and stroke work was highly significantly better with Stanford or UW solution protection than with the extracellular solutions (p less than 0.0001). Assuming a cardiac index of 50 mL.kg-1.min-1 is necessary for successful separation from cardiopulmonary bypass, only 1 of 14 extracellular and 15 of 15 Stanford and UW animals would have survived (p less than 0.0001). This study strongly suggests that extracellular cardioplegia is inferior for cardiac transplantation and that programs using this solution should reevaluate their method of myocardial protection for donor hearts.

A high index of suspicion of the presence of post-traumatic residual sequelae usually leads to early diagnosis of these lesions. The type and site of the traumatic impact and the presenting symptoms and signs frequently suggest the type of problem. The use of the appropriate diagnostic tests and the institution of suitable therapy will protect the patients from more serious subsequent complications and frequently will result in the restoration of their health to its preinjury status.