Outcomes and long-term survival for patients undergoing mitral valve repair versus replacement: effect of age and concomitant coronary artery bypass grafting.

BACKGROUND: A paucity of literature is available on the effects of age and coronary artery bypass grafting (CABG) on the outcomes of patients undergoing mitral valve (MV) repair versus replacement. METHODS AND RESULTS: A matched study was performed using prospectively collected data from the Emory cardiovascular database from 1984 to 1997 comparing 625 MV repair patients with 625 MV replacement patients. Mean age was significantly higher in the replacement group (56+/-14 versus 55+/-14 years). Preoperative demographics and postoperative outcomes were similar between groups. Length of stay (LOS) was significantly less in the repair group (9.5+/-9.4 versus 12.3+/-13.1 days). In-hospital mortality was significantly less in the repair group (4.3% versus 6.9%), and overall 10-year survival was significantly higher in the repair group (62% versus 46%). Ten-year survival of patients <60 years of age was significantly higher in repair patients (81% versus 55%) but similar in patients > or =60 years of age (33% versus 36%, respectively). Ten-year survival of MV repair without CABG was significantly higher compared with MV replacement patients (74% versus 51%) but similar to patients with concomitant CABG (28% versus 34%, respectively). Independent predictors of long-term mortality included increasing age, urgent/emergent status, female sex, diabetes mellitus, increasing weight, heart failure, decreasing ejection fraction, concomitant CABG, and MV replacement. CONCLUSIONS: Mitral valve repair has reduced LOS and improved in-hospital and 10-year survival. However, in the present series, MV repair does not provide significant long-term survival benefit over MV replacement in patients older than 60 years of age or those requiring concomitant CABG.

Twenty-year survival after coronary artery surgery: an institutional perspective from Emory University.

BACKGROUND: Coronary artery bypass graft (CABG) surgery has been performed frequently for symptomatic coronary atherosclerotic heart disease for more than 30 years. However, uncertainty exists regarding the relationship between long-term survival after CABG and readily available clinical correlates of mortality. METHODS AND RESULTS: We studied outcome at 20 years by age, sex, and other variables in 3939 patients who had CABG surgery from 1973 to 1979 in the Emory University System of Healthcare. Twenty-year survival, freedom from myocardial infarction, and freedom from repeat CABG were 35.6% (95% confidence interval [CI], 33.9% to 37.3%), 66.6% (95% CI, 64.6% to 68.6%), and 59.1% (95% CI, 56.9% to 61.5%). Multivariate correlates of late mortality were age (hazard ratio [HR], 1.46 per 10 years), female sex (HR, 1.21), hypertension (HR, 1.44), angina class (HR, 1.07 per class increase of 1), prior CABG (HR, 1.72), ejection fraction (HR, 1.07 per 10-point decrease), number of vessels diseased (HR, 1.11 per 1-vessel increase), and weight (HR, 1.04 per 10 kg). Twenty-year survival by age was 55%, 38%, 22%, and 11% for age <50, 50 to 59, 60 to 69, and >70 years at the time of initial surgery. Survival at 20 years after surgery with and without hypertension was 27% and 41%, respectively. Similarly, 20-year survival was 37% and 29% for men and women. CONCLUSIONS: Symptomatic coronary atherosclerotic heart disease requiring surgical revascularization is progressive with continuing events and mortality. Clinical correlates of mortality significantly impact survival over time and may help identify long-term benefits after CABG.

Outcomes of repeat revascularization in diabetic patients with prior coronary surgery.

OBJECTIVES: This study evaluated both short- and long-term outcomes of diabetic patients who underwent repeat coronary artery bypass graft surgery (CABG) or percutaneous coronary intervention (PCI) after initial CABG. BACKGROUND: Although diabetic patients who have multivessel coronary disease and require initial revascularization may benefit from CABG as compared with PCI, the uncertainty concerning the choice of revascularization may be greater for diabetic patients who have had previous CABG. METHODS: Data were obtained over 15 years for diabetic patients undergoing PCI procedures or repeat CABG after previous coronary surgery. Baseline characteristics were compared between groups, and in-hospital, 5-year, and 10-year mortality rates were calculated. Multivariate correlates of in-hospital and long-term mortality were determined. RESULTS: Both PCI (n = 1,123) and CABG (n = 598) patients were similar in age, gender, years of diabetes, and insulin dependence, but they varied in presence of hypertension, prior myocardial infarction, angina severity, heart failure, ejection fraction, and left main disease. In-hospital mortality was greater for CABG, but differences in long-term mortality were not significant (10 year mortality, 68% PCI vs. 74% CABG, p = 0.14). Multivariate correlates of long-term mortality were older age, hypertension, low ejection fraction, and an interaction between heart failure and choice of PCI. The PCI itself did not correlate with mortality. CONCLUSIONS: The increased initial risk of redo CABG in diabetic patients and the comparable high long-term mortality regardless of type of intervention suggest that, except for patients with severe heart failure, PCI be strongly considered in all patients for whom there is a percutaneous alternative.

Valve replacement in patients on chronic renal dialysis: implications for valve prosthesis selection.

BACKGROUND: Reports are sparse describing heart valve replacement in patients with end-stage renal disease. This review assesses a 15-year experience and outcomes after valve replacement in patients on chronic preoperative renal dialysis. METHODS: A computerized database, hospital records, and telephone contact provided outcome data for patients on chronic dialysis undergoing valve replacement between March 22, 1985, and October 13, 2000, in two hospitals. RESULTS: Seventy-two patients underwent 95 valve procedures (74 operations). Ages ranged from 23 years to 84 years (mean, 57 years). Fifty-five aortic, 30 mitral, and 3 tricuspid valve replacements and 7 valvuloplasties were performed. Six of the 74 procedures were reoperative valve replacements. In the 46 patients with reliable long-term (greater than 30 days) follow-up data, significant bleeding or stroke was documented in 17 of 34 patients with a mechanical valve and 1 of 12 patients with a bioprosthetic valve. Overall survival (including two operative deaths) was 72.8% at 3 months, 65.4% at 6 months, 60.5% at 1 year, 39.8% at 2 years, 28.5% at 3 years, and 15.9% at 6 years (Kaplan-Meier). Type of valve implanted did not influence early and late survival. CONCLUSIONS: In this series of patients on chronic dialysis, survival appears to justify valve replacement. However, the sixfold higher incidence of late bleeding or stroke in patients on dialysis with a mechanical valve requiring warfarin suggests that bioprosthetic valves are the valve substitute of choice in patients on chronic dialysis.

Perfusion-assisted direct coronary artery bypass provides early reperfusion of ischemic myocardium and facilitates complete revascularization.

BACKGROUND: Perfusion-assisted direct coronary artery bypass (PADCAB) was developed to initiate early reperfusion of grafted coronary artery segments during off-pump operations to resolve episodes of myocardial ischemia and avoid its sequelae. This case series outlines intraoperative findings and clinical outcomes of our first year clinical experience with PADCAB. METHODS: From November 1999 to November 2000, 169 PADCAB and 358 off-pump coronary artery bypass procedures were performed at the Emory University Hospitals. The decision to use PADCAB was predicated on surgeon preference. Perfusion pressure and flow, amount of intracoronary nitroglycerin, and total perfusion time and volume were recorded at the time of operation. RESULTS: One off-pump coronary artery bypass patient required emergent conversion to cardiopulmonary bypass. Two PADCAB patients had ischemic ventricular arrhythmias during target vessel occlusion that resolved once active perfusion had begun. Perfusion pressure in PADCAB grafts was on average 44% higher than mean arterial pressure (p < 0.001). Nitroglycerin, infused locally by PADCAB, was used in 67 patients to resolve ischemic episodes and increase initial coronary flows. The mean number of diseased coronary territories and grafts placed was 2.8 +/- 0.5 and 3.4 +/- 0.7, respectively, in the PADCAB group, and 2.3 +/- 0.8 and 2.7 +/- 1.0, respectively, in the off-pump coronary artery bypass group (p < 0.001 for both comparisons). More PADCAB patients received lateral wall grafts than off-pump coronary artery bypass patients (83.4% vs 59.4%; p < 0.001). Hospital death and postoperative myocardial infarction were not different between groups. CONCLUSIONS: PADCAB can provide suprasystemic perfusion pressures and a means to add vasoactive drugs to target coronary vessels. PADCAB provides early reperfusion of ischemic myocardium and facilitates complete revascularization of severe multivessel coronary artery disease.

The Carbomedics Top Hat supraannular aortic valve: a multicenter study.

BACKGROUND: Introduced in 1993, the Carbomedics Top Hat (Sulzer, Carbomedics, Austin, TX) valve is a bileaflet mechanical aortic prosthesis designed to be placed in a supraannular position. Five institutions pooled their clinical experiences to evaluate early outcome in patients with this prosthesis. METHODS: From 1994 to 2000, 639 patients underwent aortic valve replacement with Top Hat (Sulzer Carbomedics) valves at 5 institutions. Mean age was 60 +/- 13 years. In this heterogeneous population, 28% of patients had previous cardiac operations and 64% had concomitant procedures, including procedures involving more than 1 heart valve in 32%. Implanted prostheses sizes included the 19 mm (15%), 21 mm (37%), 23 mm (33%), 25 mm (13%), and 27 mm (2%). Mean follow-up was 2.0 +/- 1.5 years, and there were 1,206 patient-years of follow-up available for analysis. RESULTS: Thirty-day mortality was 5.3%. Five-year survival was 74%. Risk factors for death included older age (p = 0.01), decreased ejection fraction (p = 0.007), and increased New York Heart Association functional class (p = 0.003). Five-year freedoms from thromboembolism and hemorrhage were 90% and 85%, respectively. Five-year freedoms from explant and endocarditis were both 99%. There were no structural valve failures. CONCLUSIONS: The Top Hat valve outcomes have been similar to those of the standard Carbomedics intraannular prostheses. The unique design of the Top Hat valve, with all its components in the aortic sinuses, has particular advantages in the small aortic root, in settings where leaflet entrapment may occur, and in multiple valve replacement.

Early administration of clopidogrel is safe after off-pump coronary artery bypass surgery.

BACKGROUND: Patients who undergo off-pump coronary artery bypass graft surgery (OPCAB) may be hypercoagulable with an increased risk of graft thrombosis due to the lack of platelet dysfunction that accompanies "on-pump" surgery. Clopidogrel may be indicated in these patients to prevent recurrent ischemic events. The purpose of this observational study was to determine the safety of early clopidogrel administration after OPCAB. METHODS: Thirty-day follow-up of 364 consecutive OPCAB patients (January to June, 2002) was determined from a computerized database. One hundred ninety-three patients received clopidogrel 4 hours postoperatively if chest tube output was less than 100 cc/h for 4 hours, then daily for 4 weeks. Aspirin was administered preoperatively and postoperatively to all patients. Telephone follow-up was made 6 to 12 months after OPCAB. RESULTS: None of the patients who received clopidogrel in the early postoperative period required reoperation for mediastinal hemorrhage. Mean chest tube drainage at 24 hours was 1,024 +/- 563 mL in patients who received clopidogrel and 942 +/- 501 mL in patients who did not receive clopidogrel. The total number of blood units transfused and the number of patients receiving blood transfusions were similar between groups. In-hospital mortality was 1.6% in patients who received clopidogrel and 3.5% in patients who did not receive clopidogrel. No group differences in mortality or adverse cardiac events were observed at 6 months. Gastrointestinal bleeding occurred in 2.2% clopidogrel patients versus 0.7% of patients who did not receive clopidogrel. CONCLUSIONS: When administered according to our postoperative protocol, OPCAB patients can safely receive clopidogrel in the early postoperative period without increased risk for mediastinal hemorrhage.

Emergency coronary artery bypass grafting can be performed safely without cardiopulmonary bypass in selected patients.

BACKGROUND: Patients requiring emergency surgical revascularization are often not considered for off-pump coronary artery bypass grafting (OPCAB). METHODS: From 1996 to 2003, 614 patients underwent emergency coronary artery bypass grafting (Society of Thoracic Surgeons definition) at an academic institution. Forty-four (7%) of these procedures were performed without cardiopulmonary bypass, while 570 were conventional coronary artery bypass procedures with cardiopulmonary bypass (CABG/CPB). Data were collected prospectively into a computerized database and reviewed retrospectively. RESULTS: Though a greater proportion of CABG/CPB patients had critical left main stenosis (15.9% vs 38.3%, p = 0.005), other preoperative risk factors were similar between groups. Completeness of revascularization (No. distal anastomoses/No. diseased vessel systems) was significantly greater in the CABG/CPB group (1.51 +/- 0.03 vs 1.25 +/- 0.07, p = 0.003). There were no differences among individual complication rates (death, cardiac reoperation, postoperative myocardial infarction, permanent cerebral vascular accident, deep sternal wound infection, renal failure requiring hemodialysis, and respiratory failure requiring reintubation). However, the combined incidence of these endpoints was significantly lower in the OPCAB group (6.8% vs 21.1%, p = 0.038). OPCAB patients received fewer blood transfusions (65.9% vs 84.9%, p = 0.004) and had a significantly shorter intensive care unit stay (1.47 vs 3.20 days, p = 0.016). In-hospital mortality (0% vs 6.3%, p = 0.168) and mean postoperative length of stay (5.48 vs 7.03 days, p = 0.414) favored OPCAB, but did not reach statistical significance. CONCLUSIONS: Off-pump coronary artery bypass can be performed safely and effectively and should be considered in selected patients with acceptable hemodynamics undergoing emergency coronary revascularization.

Intraoperative radiofrequency ablation for the treatment of atrial fibrillation during concomitant cardiac surgery.

BACKGROUND: Radiofrequency ablation has been recently introduced as an alternative to the surgical maze procedure to eliminate atrial fibrillation (AF). The purpose of this study was to examine the effectiveness of unipolar radiofrequency ablation in patients with AF undergoing open heart surgery. METHODS: A retrospective review was performed on 54 patients undergoing radiofrequency ablation with concomitant cardiac operations from March 2002 through July 2003. Forty-two patients (77.8%) received left atrial ablation, and 12 (22.2%) received biatrial ablation. RESULTS: Mean duration of preoperative AF was 46.3 +/- 44 months; 23 (42.6%) had AF 5 years or more, 32 (59.3%) had continuous AF, and 12 (22.6%) had a preoperative left atrial diameter of 6.0 cm or greater. At discharge, 33 patients (70.2%) were free from AF, 30 (62.5%) were in normal sinus rhythm, and 6 (12.7%) required a new pacemaker. Mid-term follow-up was available in 44 (93.6%) patients, with a median follow-up of 8.7 months (range, 3 to 22 months). At follow-up, 34 (77.3%) patients were free from AF. There were no significant differences in freedom from AF in patients with continuous versus intermittent AF or duration of 5 or greater years versus less than 5 years. In patients with isolated mitral valve surgery and radiofrequency ablation, 22 (88.0%) were free from AF compared with 12 (63.2%) with other operations (p = 0.074). In patients with left atrial diameter less than 6.0 cm, 30 (88.2%) were free from AF compared with 4 (40%) with left atrial diameter of 6.0 cm or greater (p = 0.006). CONCLUSIONS: Radiofrequency ablation is an effective surgical option for the treatment of continuous or intermittent AF. The elimination of AF using radiofrequency ablation is most successful in patients undergoing isolated mitral valve surgery with preoperative left atrial diameter less than 6.0 cm.