A comparison of ON-PUMP vs OFF-PUMP coronary artery bypass surgery among low, intermediate, and high-risk patients: the Hartford Hospital experience.

BACKGROUND: Off-pump coronary artery bypass (OP-CAB) graft surgery is being used with increasing frequency. This study was designed to compare OP-CAB outcomes with conventional surgical revascularization using cardiopulmonary bypass (CPB) in patients with varying risk categories at a high-volume center. METHODS AND RESULTS: Between 1/1/1999 and 1/31/2001, bypass surgery was performed on 1,312 patients, including 348 OP-CAB cases and 964 CPB cases. Compared to CPB cases, OP-CAB patients were more likely to be female and had a lower incidence of three vessel coronary artery disease, prior percutaneous intervention, and prior bypass surgery. Postoperatively, OP-CAB patients had a lower incidence of renal failure and prolonged ventilatory support, as well as a lower composite endpoint of inhospital mortality, perioperative myocardial infarction, cerebrovascular accident, and/or renal failure. In addition, OP-CAB patients required fewer transfusions and had a shorter total length of hospital stay. In general, morbidity and mortality increased in both OP-CAB and CPB groups with increasing Parsonnet score. CONCLUSIONS: OP-CAB surgery is a safe and effective alternative to conventional coronary artery bypass graft (CABG) surgery, with a lower incidence of major in-hospital adverse clinical events and a decreased requirement for medical resources. Adverse OP-CAB outcomes correlate well with pre-operative Parsonnet Score.

Cardiac isoenzymes following heart transplantation.

Creatine phosphokinase (CPK) isoenzymes are commonly obtained after heart transplantation (HT) to assess myocardial injury of the donor heart. This investigation retrospectively evaluated the utility of this practice. Fifty-six recipients of orthotopic heart transplants had at least two daily CPK-MB studies following HT. All patients were followed up for at least one year (or until death). Nineteen patients had entirely negative CPK-MB determinations (NEG). Eighteen patients had a single positive CPK-MB determination, and were considered to be equivocal (EQUIV). Nineteen patients had more than one daily positive CPK-MB determination (POS). To evaluate the influence of positive CPK-MB determinations on the outcome of HT, we compared the results in the NEG and POS groups. There was no difference in the donor organ ischemic times between the two groups. The duration of follow-up for the two groups was also similar (1,192 days vs 1,020 days). The NEG and POS groups had no significant difference in: 1 year survival (84 percent vs 74 percent); freedom from treated rejection episodes in 3 months (39 percent vs 42 percent); and freedom from coronary artery disease (CAD) at 3 years (83 percent vs 86 percent). Additionally, the ejection fractions of the donor hearts were similar at 1 year post-transplant for the 2 groups (64 percent vs 59 percent). We conclude that myocardial injury, as reflected by post-transplant CPK-MB levels, does not predict one-year mortality, predisposition to rejection, predisposition to coronary artery disease, or ultimate graft dysfunction. In an effort to perform HT more economically, we no longer obtain CPK-MB levels following HT.

Endarterectomy, vein patch, and mammary bypass of the anterior descending artery.

Occasionally the left anterior descending (LAD) coronary artery contains such diffuse calcific atherosclerosis that an area suitable for distal anastomosis with the internal mammary artery (IMA) cannot be found. Additionally, the LAD of some patients contains multiple areas of stenosis, which would prevent free outflow from the IMA graft. In these cases the potentially increased operative risk of LAD endarterectomy is justified to avoid leaving poorly revascularized areas of anteroseptal heart. In an effort to provide the long-term patency benefits of IMA grafting for these patients without the technical difficulty of a lengthy IMA to LAD anastomosis, we have combined saphenous vein patch reconstruction with IMA bypass when LAD endarterectomy is required.

Repair of truncus arteriosus in the neonate and young infant.

Infants with truncus arteriosus present a difficult management issue. Because of the high operative mortality, repair is often delayed beyond the first 3 to 6 months of age. We reviewed our experience with 11 neonates and young infants with truncus arteriosus undergoing repair (median age, 21 days). Five patients also had major truncal valve insufficiency, and 2 required valve replacement. Right ventricle-pulmonary artery continuity was established with a porcine valved conduit in 3 patients and an aortic or pulmonary homograft in 8. There was 1 operative death (9%; 70% confidence limits, 3%-22%) and 1 late death over a mean follow-up of 21 months (range, 4 to 32 months). Eight of the 9 late survivors are growing normally. Echocardiographic examination revealed normal ventricular function in all patients (mean shortening fraction, 39%). Doppler assessment demonstrated trivial prosthetic or homograft valve regurgitation in 7 patients and mild to moderate obstruction in 5 patients. This recent experience with repair of truncus arteriosus indicates that the operative risk is low even in the neonate. Repair in the first month of life should be recommended before the development of critical congestive heart failure or irreversible pulmonary vascular disease.

Intrinsic failure of Hancock mitral bioprostheses: 10- to 15-year experience.

Hancock porcine bioprostheses have been implanted in the mitral position at the National Institutes of Health since July, 1970. Eight models (330, 330A, 330B, 330C, 332, 340, 341, and 342) were used during a 54-month period ending December, 1974, and 100 consecutive surviving patients were evaluated for subsequent bioprosthetic valve failure and prosthesis-related complications by annual clinic examinations and serial hemodynamic studies. Actuarial patient survival was 76 +/- 4%, 51 +/- 5%, and 30 +/- 6% after 5, 10, and 15 years, respectively. Intrinsic valve failure, defined as structural degeneration of bioprosthetic tissue or stent geometry alteration or both, in the absence of prior infection, occurred in 23 patients. The linear occurrence rate of bioprosthetic valve failure was 0.2%, 5%, and 15% per patient-year, and it affected 1 patient, 14 patients, and 8 patients at sequential 5-year milestones. The actuarial freedom from valve failure was 99 +/- 1%, 75 +/- 6%, 58 +/- 8%, and 40 +/- 12% after 5, 10, 12, and 14 years, respectively. The valve durability of early Hancock bioprostheses (models 330 through 341; N = 39) was not appreciably different from that of the current model 342 valves (N = 61). However, an increased incidence of intrinsic valve failure was observed for the first polypropylene-stented valve type (model 330) compared with the currently available model 342 valve (8/16, 50%, versus 12/61, 20%; p = 0.034). The yearly occurrence rate of prosthesis-related complications remained constant, but the rate of intrinsic valve failure increased in a progressive, nonlinear fashion. The high intrinsic failure rate of the Hancock porcine bioprosthesis after 10 to 12 years has moderated our initial enthusiasm for this valve in the mitral position, and has resulted in more frequent implantations of mechanical valve substitutes at this institution.