RESULTS OF SURGICAL REVASCULARIZATION IN ISCHEMIC HEART-FAILURE WITHOUT ANGINA

Seventeen patients with severe ischaemic heart failure without angina were studied prospectively to determine the effects of surgical revasc ularization on exercise tolerance, peak oxygen consumption and left ve ntricular function at rest and during inotropic stimulation at 3 month s after surgery. Suitability for surgery was assessed by the presence of ischaemia identified by thallium scintigraphy and stress electrocar diographic (EGG) testing and the left ventricular response to dobutami ne measured by radionuclide ventriculography. One patient died awaitin g surgery and one required cardiac transplantation. Fifteen patients u nderwent coronary artery surgery with two perioperative deaths. Thirte en patients were restudied 3 months after surgery. Mean treadmill exer cise time (362 +/- 204 s to 562 +/- 303 s, P < 0.05) and peak oxygen c onsumption (14.9 +/- 3.5 ml/kg per min to 20.8 ml/kg per min, P < 0.01 ) increased significantly. Resting ejection fraction was not changed a fter surgery (20 +/- 5% to 21 +/- 6%) but ejection fraction during dob utamine stimulation increased significantly (26 +/- 5% to 31 +/- 10%, P < 0.05), Indices of cardiac function derived from thermodilution Swa n-Ganz catheter data both at rest during dobutamine stimulation were u nchanged after surgery. At 13 +/- 3 months after surgery there had bee n three sudden deaths and one patient had undergone successful cardiac transplantation. Of the remaining nine patients three had improved to NYHA symptomatic class I, three were in NYHA class II and three in NY HA class III. Repeat treadmill exercise testing in seven patients show ed that the improvement in exercise capacity evident in the first foll ow-up visit was maintained during long-term follow-up.