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Objective: The ideal prosthesis for aortic valve replacement in patients with small annuli remains controversial and has yet to be identified. The purpose of this report is to compare the St. Jude (SJ) Medical and Medtronic Hall (MH) valves for aortic valve replacement in the small aortic root. Methods: From 1986 to 1994 we prospectively randomized 456 patients to receive either the SJ or the MH valve. From this population, 80 patients (SJ, 42 patients; MH 38 patients) had a 19 or 21 mm aortic prosthesis inserted without annulus enlarging procedure. Results: Follow-up was complete in all 80 patients for 270 patient years (mean 40.5 months). Analysis showed that the SJ and MH groups were similar with respect to age, gender, body surface area, valve area, NYHA class, ventricular function, prosthesis size, frequency of revascularization, bypass and global ischemic time. There were two operative deaths (1 SJ, 1 MH). Clinical performance and Dobutamine stress transesophageal doppler echocardiography could not demonstrate a significant advantage of one prosthesis over the other in this population. The change in aortic valve gradient, and left ventricular mass index measured preoperatively and within 12 months postoperatively were not different in both cohorts. Conclusion: The study could not detect a difference in the performance of the SJ and MH heart valves for aortic valve replacement in patients with small aortic annuli.

The clinical and billing records of 250 patients (173 men and 77 women) undergoing isolated coronary artery bypass grafting between 1987 and mid-1990 were retrospectively reviewed to determine charges and clinical results as related to age. Patients were stratified by age into five groups of 50 consecutive patients each: group 1, less than 50 years of age; group 2, 50 to 59 years; group 3, 60 to 69 years; group 4, 70 to 79 years; and group 5, 80 years or older. The groups were compared in regard to perioperative clinical variables, long-term follow-up, and total charges. Group 5 had significantly more postoperative complications than the other four groups (p0.05). In addition, length of postoperative hospitalization was significantly longer in group 5 compared with groups 1, 2, and 3 (p0.05), and operative mortality in group 5 (20%) was significantly higher than that in the other four groups. The mean total charges for group 5 were $73,399, which was significantly higher than the totals in the other four groups (p0.05). Actuarial 3-year survival for the hospital survivors was 87%, 89%, 78%, 82%, and 60% for groups 1, 2, 3, 4, and 5, respectively (p0.001). Postoperative performance as measured by the Karnofsky scale was significantly lower in group 5 than in groups 1 and 2 (p0.05). These data support the premise that elderly patients undergoing coronary artery bypass grafting have more complications, longer hospitalizations, and higher operative mortality than younger patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Although bridging to cardiac transplantation has become a therapeutic option for transplant candidates whose condition deteriorates while they are awaiting a donor heart, short-term efficacy has not been proved and long-term survival has not been reported. We retrospectively reviewed data on 44 patients who had circulatory assist devices placed as a bridge to transplantation between May 1985 and April 1993. The 35 male and nine female patients ranged in age from 12 to 65 years (mean 43.8 years). Thirty-one patients were supported with 32 Thoratec (18 left ventricular, 14 biventricular), 11 Novacor, and two Jarvik J-7-70 devices. The duration of device support was from 4 hours to 440 days (mean 45.5 days). Fifteen patients did not receive a donor organ because of infection (ten patients), renal failure (five patients), bleeding (nine patients), cerebrovascular accident (three patients), ventricular fibrillation (one patient), and right heart failure (one patient), and all died. Two patients were weaned from support and survived without transplantation. Twenty-seven patients underwent transplantation, and 26 survived (96%). Overall survival was 64% (28/44). Duration of survival ranged from 2 to 96 months (mean 35 months). Among the 28 hospital survivors, there were four late deaths (all transplant recipients) at 3, 6, 14, and 68 months. Posttransplantation actuarial survivals at 1, 5, and 8 years are 88%, 83%, and 66%. Twenty-three of the 24 patients presently alive are in New York Heart Association functional class I. These data demonstrate the short- and long-term efficacy of bridging to transplantation with circulatory support devices. The excellent survival and full functional recovery of patients undergoing transplantation ensure that donor organs are not being "wasted" on the sickest patients.

From March 1990 through January 1992, 108 patients undergoing myocardial revascularization had one (91) or both (17) inferior epigastric arteries (IEA) used for myocardial revascularization. The internal thoracic artery (ITA) was used bilaterally in 87 patients. Of the 373 distal anastomoses, 210 (56%) were with the ITA, 130 (35%) with the IEA, and 12 (3%) with the gastroepiploic artery. Nineteen patients (18%) received 21 saphenous veins. When compared with the ITA, the IEA demonstrated a longer harvest time (36.5 vs 29.6 min, P0.0001), a shorter usable length (11.9 cm vs 16.5 cm, P0.001), and similar flow (49.7 cc/min vs 48.7 cc/min, P = NS). The operative mortality was 2.8%. Two deaths resulted from low cardiac output and the one remaining death from complications of a cerebral vascular accident. The most common major complication was respiratory insufficiency, which occurred in 11 patients (12%). There were two sternal infections (2%), and two abdominal wound infections (2%), none of which were fatal. The IEA is an acceptable additional arterial conduit. It can be safely employed with one or both ITAs. Short-term and long-term patency must be established before preferential use of this conduit is advised.

The intraaortic balloon pump is usually the first mechanical device inserted for perioperative cardiac failure; however, little current information is available regarding short- and long-term effectiveness. From January 1983 through November 1990, 6856 adult patients underwent cardiac surgical procedures, 580 of whom (8.5%) had an intraaortic balloon inserted preoperatively (107 patients), intraoperatively (419 patients), or postoperatively (54 patients). There were 374 men and 206 women with a mean age of 63.9 years (range 19 to 88). Operations included 376 coronary artery bypass grafts, 100 mitral valve replacements (with or without bypass grafting), 70 aortic valve replacements (with or without bypass grafting), 15 double valve replacements (with or without bypass grafting), and 32 other procedures. There were 72 (12.4%) complications related to the balloon pump, of which 42 necessitated surgical intervention including thrombectomy (21), vascular repair (13), fasciotomy (2), aortic repair (1), and amputation (4). Operative mortality for patients supported by the balloon pump was 44%. Multivariate stepwise analysis of 27 parameters revealed six independent predictors of mortality: preoperative New York Heart Association class, transthoracic intraaortic balloon insertion (both p < 0.0001), preoperative administration of intravenous nitroglycerin, age, female gender, and preoperative balloon insertion (p < 0.001). Balloon-related complications were not predictive of death. Of the 326 hospital survivors, only 34 were lost to follow-up. There were 75 late deaths, the cause of which was cardiac in 41 (55%), noncardiac in 20 (27%), and unknown in 14 (19%). Actuarial survivals at 1, 5, and 9 years are 51%, 42%, and 33%. Of the 217 hospital survivors still alive and contacted, 81% were in class I (114) or II (60). These data demonstrate (1) operative mortality for patients requiring an intraaortic balloon in the perioperative period remains high, (2) perioperative risk factors can be identified, (3) complications related to the balloon pump do not affect survival, (4) operative survivors can achieve prolonged survival with excellent functional results, and (5) consideration for alternative methods of circulatory support is justified.

To better define the merits of the bileaflet and tilting-disc valves, we prospectively randomized 102 patients (mean age, 57 years; range, 11 to 85 years) to receive either the St. Jude (n = 55) or the Medtronic-Hall (n = 47) mitral valve prosthesis between September 1986 and May 1991. The two groups were not different with respect to preoperative New York Heart Association class, incidence of mitral stenosis and insufficiency, angina score, extent of coronary artery disease, ventricular function, completeness of revascularization, or cross-clamp or bypass time. The hospital mortality (14.5% versus 10.6%, St. Jude versus Medtronic-Hall) and late mortality (7.3% versus 2.1%) were not significantly different. Follow-up was complete in 84 of 89 hospital survivors (94%) with a mean of 26 months (range, 1 to 60 months). The linearized rates of valve-related events and the 3-year actuarial survival demonstrated no significant differences between both cohorts. Comparison of the clinical outcome and echocardiographic parameters obtained at the time of follow-up demonstrated no significant differences between the two prostheses. These data indicate that the Medtronic-Hall and St. Jude mitral prostheses are similar with respect to their rates of valve-related complications and hemodynamic profiles. This study suggests that there is no difference between the St. Jude and Medtronic-Hall prostheses with regard to early clinical performance or hemodynamic results and therefore does not support the preferential selection of either prosthesis.

The internal mammary artery (IMA) is the conduit of choice for myocardial revascularization. From 1972 to 1989, 586 patients received bilateral IMA and supplemental vein grafts. There were 506 men (86%) and 79 women (14%) with a mean age of 55.5 years (range 32-77 years). Unstable angina was present in 138 patients (24%), insulin-requiring diabetes mellitus in 83 (14%) and previous myocardial infarction (MI) in 25 (4%). Preoperative angiography demonstrated triple-vessel disease in 286 patients (49%) and double-vessel disease in the remaining 300 patients (51%). Left main coronary artery disease (stenosis greater than or equal to 50%) was present in 53 (9%). The mean left ventricular score was 7.4 with a range of 5 to 20. The mean number of grafts performed was 3.4 per patient. Hospital mortality was 3.6% (21 patients). Follow-up was done through direct patient contact, via the patient's physician or by telephone contact with the patient themselves or surviving family members. Follow-up was complete in 518 hospital survivors and ranged from 1 month to 17.5 years with a cumulative follow-up of 911 patient years. At 10 and 15 years, respectively, the actuarial freedom from MI was 78% and 72% and freedom from reoperation was 93% and 86%. Actuarial survival at 10 and 15 years was 85% and 70%, respectively. This longitudinal analysis demonstrates that bilateral IMA grafting has a low operative risk. The data suggest that utilization of two IMA grafts yield excellent freedom from recurrent symptoms and provides excellent long-term survival.

Background Management of asymptomatic mild aortic stenosis at the time of coronary artery bypass grafting (CABG) remains controversial. We have retrospectively analyzed a cohort of patients requiring aortic valve replacement (AVR) subsequent to CABG and compared their operative morbidity and mortality with that of a group receiving CABG and AVR simultaneously at the first operation. Methods Analysis is drawn from 28 patients who required AVR 8 ± 4 years subsequent to CABG (group A) and 175 patients receiving AVR along with CABG at the primary operation (group B). Groups were similar with respect to age, sex, risk factors for cardiac disease, extent of coronary artery disease, left ventricular function, New York Heart Association class, aortic valve area, number of grafts, and size of prosthesis inserted. Results Patients having AVR subsequent to CABG had a significantly prolonged aortic cross-clamp time and global myocardial ischemic time and incurred a twofold increase in operative mortality. The actuarial survival at 10 years was not significantly different between cohorts. In the 28 patients in group A, the aortic valve area during the period between operations decreased 0.05 mm 2 /y. Conclusions The operative mortality and morbidity of a second operation for AVR is high, but there is no significant difference in survival at 10 years. In at least a portion of patients having mild aortic stenosis at the time of CABG there will be progression of the stenosis necessitating reoperation at a later date.

Although bridging to cardiac transplantation has become a therapeutic option for transplant candidates whose condition deteriorates while they are awaiting a donor heart, short-term efficacy has not been proved and long-term survival has not been reported. We retrospectively reviewed data on 44 patients who had circulatory assist devices placed as a bridge to transplantation between May 1985 and April 1993. The 35 male and nine female patients ranged in age from 12 to 65 years (mean 43.8 years). Thirty-one patients were supported with 32 Thoratec (18 left ventricular, 14 biventricular), 11 Novacor, and two Jarvik J-7-70 devices. The duration of device support was from 4 hours to 440 days (mean 45.5 days). Fifteen patients did not receive a donor organ because of infection (ten patients), renal failure (five patients), bleeding (nine patients), cerebrovascular accident (three patients), ventricular fibrillation (one patient), and right heart failure (one patient), and all died. Two patients were weaned from support and survived without transplantation. Twenty-seven patients underwent transplantation, and 26 survived (96%). Overall survival was 64% (28/44). Duration of survival ranged from 2 to 96 months (mean 35 months). Among the 28 hospital survivors, there were four late deaths (all transplant recipients) at 3, 6, 14, and 68 months. Posttransplantation actuarial survivals at 1, 5, and 8 years are 88%, 83%, and 66%. Twenty-three of the 24 patients presently alive are in New York Heart Association functional class I. These data demonstrate the short- and long-term efficacy of bridging to transplantation with circulatory support devices. The excellent survival and full functional recovery of patients undergoing transplantation ensure that donor organs are not being "wasted" on the sickest patients.

The purpose of this study was to determine if the addition of potassium to reinfusion cold blood cardioplegia (CBC) offers an advantage over cold blood alone. Forty patients matched for age, left ventricular function, extent of coronary disease and number of vessels bypassed were prospectively randomized. Each patient received an initial dose of CBC (10 cc/kg) with potassium. Group I patients (n = 23) received subsequent infusions of CBC (5 cc/kg) containing potassium while Group II patients (n = 17) received cold blood only. The cross-clamp time, mean infusate volume and temperature were not significantly different in the two groups. Following reperfusion, the cardiac index and the CPK isoenzyme release at 0.5, 1, 8, and 12 h after cross-clamp release were not significantly different between the groups. The postoperative appearance of new Q-waves, inotropic agent requirement, and reversal of the lactate dehydrogenase (LDH) isoenzyme ratio were also not significantly different in the two groups. The study demonstrated that following initial arrest with potassium, cold blood is equally as effective as potassium blood cardioplegia in protecting the ischemic myocardium.

The intraaortic balloon pump is usually the first mechanical device inserted for perioperative cardiac failure; however, little current information is available regarding short- and long-term effectiveness. From January 1983 through November 1990, 6856 adult patients underwent cardiac surgical procedures, 580 of whom (8.5%) had an intraaortic balloon inserted preoperatively (107 patients), intraoperatively (419 patients), or postoperatively (54 patients). There were 374 men and 206 women with a mean age of 63.9 years (range 19 to 88). Operations included 376 coronary artery bypass grafts, 100 mitral valve replacements (with or without bypass grafting), 70 aortic valve replacements (with or without bypass grafting), 15 double valve replacements (with or without bypass grafting), and 32 other procedures. There were 72 (12.4%) complications related to the balloon pump, of which 42 necessitated surgical intervention including thrombectomy (21), vascular repair (13), fasciotomy (2), aortic repair (1), and amputation (4). Operative mortality for patients supported by the balloon pump was 44%. Multivariate stepwise analysis of 27 parameters revealed six independent predictors of mortality: preoperative New York Heart Association class, transthoracic intraaortic balloon insertion (both p0.0001), preoperative administration of intravenous nitroglycerin, age, female gender, and preoperative balloon insertion (p0.001). Balloon-related complications were not predictive of death. Of the 326 hospital survivors, only 34 were lost to follow-up. There were 75 late deaths, the cause of which was cardiac in 41 (55%), noncardiac in 20 (27%), and unknown in 14 (19%). Actuarial survivals at 1, 5, and 9 years are 51%, 42%, and 33%. Of the 217 hospital survivors still alive and contacted, 81% were in class I (114) or II (60). These data demonstrate (1) operative mortality for patients requiring an intraaortic balloon in the perioperative period remains high, (2) perioperative risk factors can be identified, (3) complications related to the balloon pump do not affect survival, (4) operative survivors can achieve prolonged survival with excellent functional results, and (5) consideration for alternative methods of circulatory support is justified.

Transient neurological and visual signs have been observed in some patients after valved conduit replacement of the aortic valve and ascending aorta. Twenty-seven patients having valved conduit replacement between February 1982 and October 1988 were compared with 21 patients having combined aortic valve replacement (AVR) and ascending aorta (AA) graft replacement. Follow-up in 100% of both groups was obtained for 0.3-6.6 years (mean, 2.6 +/- 0.3 years). Among 20 surviving valved conduit patients, 10 (50.0%) experienced repetitive neurological and visual signs, including scotomata (seven), transient motor ischemic attacks (two), amaurosis fugax (four), and recurring attention lapses suggesting petit mal seizures (one). No patient with AVR + AA graft experienced any events (p = 0.004). All valved conduit and seven (53.8%) of AVR + AA graft patients were on warfarin (p = 0.0016). These events retained the same pattern although they diminished in frequency after 12 months in seven patients (70.0%) and after initiation of dipyridamole in two patients. Rehabilitation was similar in both groups: 18 of 20 (90.0%) valved conduit and 12 of 16 (75.0%) AVR + AA graft patients (p = NS). Transient, repetitive, nonprogressive neurological and ophthalmological phenomena are frequent after valved conduit replacement. The pathophysiological mechanism is unclear, but antiplatelet therapy may provide symptomatic control.

There is controversy whether the short-term and long-term results of coronary artery bypass grafting in elderly patients justify performing the procedure. Between January 1977 and December 1986, 4580 patients underwent coronary artery bypass grafting, of whom 222 (4.9%) were 75 years old or older (mean 77 years). There were 143 men and 79 women and 139 (63%) were in New York Heart Association class IV. One hundred forty-six patients (66%) had had at least one preoperative myocardial infarction. Myocardial revascularization was performed under emergency conditions in 17 patients (18%). The mammary artery was used in 43%, 96% of the patients received two or more grafts. The mean number of bypass grafts was 3.1 per patient. The overall hospital mortality rate was 10.8% (24/222), 3.6% for elective procedures, 14.9% in urgent cases, and 35% in emergencies. In contrast, the overall early mortality rate was 3.1% in 4358 patients less than 75 years old. Complications occurred in 83 patients (37%). Of the patients discharged from the hospital, 198 were followed up for a mean of 48 months (1 to 130). Actuarial probability of survival was 75% at 48 months. Postoperatively 70% were in New York Heart Association class I or II and only 21% were rehospitalized for cardiac problems. During the follow-up period 77% of the patients were free from angina, and of those experiencing angina the mean time from operation to the first episode was 75 months. Although elderly patients have a somewhat increased operative mortality rate, particularly if operated on urgently or emergently, long-term survival and freedom from angina are excellent and justify continued performance of coronary bypass grafting in selected patients over 75 years of age.

The superior vena cava (SVC) and thoracic inferior vena cava (IVC) were replaced in 46 dogs with autologous vein, knitted Dacron, glutaraldehyde-fixed porcine pericardium, unsupported polytetrafluorethylene (PTFE), and externally stented PTFE. After 30 days, patency rates were determined by contrast venography and were 100%, 9%, 50%, 75%, and 100%, respectively. The patency rates of Dacron and glutaraldehyde-fixed pericardium are considered unacceptable when compared to autologous vein (p less than 0.05). Stented PTFE exhibited a patency rate equal to that of autologous vein at 30 days, minimal graft reaction, excellent incorporation by host fibroblasts, and a smooth neointima. The external spiral support added to PTFE enchanced the thromboresistance of this graft in the thoracic venous system. Long-term follow-up is required to determine if the stented PTFE prosthesis remains comparable to autologous vein as a venous conduit.

Extracardiac conduits are essential in operations for congenital discontinuity between the right ventricle and the pulmonary artery. The disturbing degree of obstruction reported in clinical series of extracardiac conduits containing porcine valves has been attributed in part to early valve deterioration and the development of a thick neonintimal lining within the Dacron graft. This study compares the hemodynamic differences and the thickness of the neointimal lining in right ventricular extracardiac conduits with and without a porcine valve. Woven Dacron conduits (16 mm) were implanted in 15 adult mongrel dogs, and then the proximal pulmonary artery was occluded with Dacron tape. In six dogs, the extracardiac conduit contained a porcine valve, whereas in the other nine it did not. Cardiac output, transconduit gradient, and resistance were measured at operation and 6 and 12 months postoperatively in both groups. No hemodynamic differences were noted. After 1 year, the thickness of the neointimal lining was threefold greater in valved conduits (1,370 +/- 313.1 mu versus 367 +/- 28.07 mu, p less than 0.005). The neointima along the Dacron graft was thickest proximal and distal to the porcine valve. The luminal peel in valved conduits contained fenestrations and intimal flaps, similar to those observed clinically. In our model, a porcine valve in a right ventricular extracardiac conduit is associated with intimal hyperplasia not seen in nonvalved conduits. If the pulmonary vascular resistance is normal, then the absence of a valve within the conduit does not significantly change hemodynamics and may warrant clinical application to prevent late conduit obstruction.