Applicability of noncardioplegic coronary bypass to high-risk patients. Selection of patients, technique, and clinical experience in 3000 patients.

Although some surgeons still prefer noncardioplegic coronary bypass, most surgeons are skeptical of its suitability for high-risk patients. We analyzed the first 3000 patients who had primary coronary bypass without cardioplegia since our program's inception. Patients with reoperations, valve operations, or carotid endarterectomies were excluded. Multivariate predictors of operative death included age, sex, left ventricular dysfunction, preoperative intraaortic balloon pumping, and urgency of operation. Eight hundred seventy-nine patients (29%) were more than 70 years of age; 795 (27%) were female; 290 (9.7%) had an ejection fraction less than 0.30, and another 77 (2.6%) had left ventricular aneurysms; 196 (6.5%) had an acute myocardial infarction, and another 397 (13%) had a myocardial infarction less than 1 week preoperatively; 917 (31%) had rest pain in the hospital (preinfarction angina). Only 790 (26%) had elective operations. The overall operative mortality rate was 1.47% (44/3000): The mortality rate for elective operations was 0.5% (4/790); urgent 1.7% (28/1687); emergency 2.3% (12/523). In patients with an ejection fraction less than 0.30 the mortality rate was 6.2% (18/290); with age more than 70 years, it was 3.9% (34 of 879); with acute myocardial infarction it was 3.1% (6/196); and with left ventricular aneurysmectomy it was 1.3% (1/77). Inotropic support after leaving the operating room was needed in 6.6% (199 patients), and 1% (30 patients) required new intraaortic balloon pumping postoperatively (two of these 30 patients died). These results provide reassurance that noncardioplegic coronary artery bypass grafting provides excellent myocardial protection and operating conditions for primary coronary bypass and is particularly suitable for high-risk patients.

Coronary bypass with substrate-enhanced cardioplegia versus non-cardioplegic technique for early revascularization in acute infarction.

Nine patients chosen at random received substrate enhanced cardioplegia (SECP) for early (less than 4 h) revascularization in acute infarction. A control group of 9 patients with similar clinical characteristics was chosen from the larger group revascularized concurrently with a noncardioplegic technique (NCP). There were no significant differences between the NCP and SECP groups respectively in preoperative clinical parameters such as age (62.8 vs. 62.3 years), sex (7 men, 2 women in both groups), ejection fraction (50% vs. 56%) or number of diseased vessels (2.1 vs 2.3). Intraoperative aortic clamp times were significantly shorter in NCP patients (11 vs. 38 min), and 4 NCP patients had no clamping. The internal mammary artery (IMA) was used in 6 NCP patients and 1 SECP patient (to a nonoccluded branch vessel). Postoperatively, NCP patients had higher peak CPK-MB (284 vs. 190 IU/l), longer use of inotropes (10 vs. 2.7 h) and intraaortic balloon pump (15 vs. 8 h), and a higher ejection fraction before discharge from hospital, but none of these differences were significant. SECP appears to provide better myocardial performance early postoperatively, but lasting benefits were not apparent in this subset of patients with early revascularization. Because the IMA has a powerful effect on long term survival but is very difficult to use with antegrade SECP, we continue to favor the IMA without SECP in hemodynamically stable, young patients (less than 65 years) who are revascularized early after infarction.

Postoperative fibrous cardiac constriction.

Two patients with postoperative fibrous cardiac constriction are described. Unlike postoperative pericardial or epicardial constriction, the fibrous constricting layer in these patients envelopes the vein bypass grafts and is separate from the pericardium, which is not involved. Surgical management of these patients is difficult and hazardous; a strategy is outlined.

Accuracy of sizers for aortic valve prostheses.

Accurate sizing of the aortic anulus is a prerequisite of prosthetic valve implantation, because it is usually desirable to insert the largest possible prosthesis. Although it is generally assumed that commercial valve sizers are accurately labeled, our measurements reveal that the sizers for the St. Jude Medical, Björk-Shiley, and Ionescu-Shiley prostheses are larger than their nominal sizes. These findings are relevant to the selection of prosthetic valves.