25 years of aortic valve replacement using mechanical valves. Risk factors for early and late mortality.

This study describes the changes that have taken place in patient characteristics in 25 years of aortic valve replacement using mechanical valves, and looks for risk factors for early and late mortality. During this period, 1449 mechanical valves were implanted. Overall early mortality (< 30 days) was 5.3% and for aortic valve replacement without concomitant procedures 3.9%. Overall survival rates at 5, 10 and 15 years were 80%, 63% and 49%, respectively. Despite an increased proportion of higher risk patients (older age, more reoperations, more concomitant coronary bypass surgery) survival rates improved throughout the study period. Early mortality was related to an early year of operation, urgency, reoperation and concomitant surgery to the tricuspid valve or ascending aorta. Late mortality was higher for patients of older age, with an early year of operation, male gender, concomitant coronary bypass surgery, mitral valve surgery or replacement of the ascending aorta. Aortic regurgitation did not have a major influence on early nor late mortality. The improvement in early and late mortality in more recent years was largely the result of the introduction of cardioplegia. A changing, non-proportional effect was observed for several risk factors during the follow-up period. This study illustrates the changes and improvements in medical care that have taken place in patients requiring aortic valve replacement.

Aorto-coronary bypass surgery in 62 patients with severe left ventricular dysfunction--a follow-up study.

Long-term follow-up of 62 consecutive patients with severe left ventricular dysfunction (ejection fraction = less than 0.30) and disabling angina pectoris following aorto-coronary bypass surgery was investigated. Prior to surgery all patients had angina pectoris and a history of remote myocardial infarction, 35% were in congestive heart failure (CHF). Significant stenoses in 3 major coronary vessels were present in 51 patients (82%). An average of 3.5 grafts per patient were employed. Operative mortality (30 days) rate was 4.8% (3 patients) and 13 patients died during the following period. The average follow-up was 37 months (range: 6 to 116 months). At follow-up, the 5-year survival probability for these patients was 70% (SD = 9%). Thirty-one patients (67%) of the 46 survivors had complete relief of angina, but signs of CHF were still evident in 17 patients (36%). Compared to patients with ejection fractions above 0.30% (surgical mortality 1.4% and 5-year survival rate 94% (SD = 3%] the outcome of coronary artery bypass grafting in patients with poor left ventricular function showed a significantly higher surgical mortality (P = 0.03) and impaired long-term survival (P = 0.02). However, aorto-coronary bypass grafting can be performed in patients with severe left ventricular dysfunction with reasonable relief of angina and with an acceptable surgical mortality.

Pulmonary wedge injections yielding left-sided echocardiographic contrast.

Ultrasound contrast on the left side of the heart without the need for left heart catheterisation was achieved by hand injections of 8 to 10 ml 5 per cent dextrose solution through a catheter in the pulmonary wedge position. Injections were performed in 18 patients undergoing routine cardiac catheterisation and M-mode or two-dimensional echocardiography was used. An adequate wedge position was attained in 17 of the 18 patients. Nine had injections through Cournand catheters, three through Swan-Ganz catheters, and five through both. In 11 of these 17 patients left atrial or left ventricular echocardiographic contrast was seen immediately after wedge injection. Two patients showed diminished or absent contrast on later injections from the same position. Better results were obtained with the Cournand catheter (11/15 positive) than with the Swan-Ganz (1/8 positive) catheter. Pulmonary artery injections proximal to the wedge position did not cause left-sided contrast. No complications were observed. The safety of this method remains to be determined.