Effects of carvedilol in patients with impaired left ventricular function due to ischaemic heart disease

Abstract

In this single-blind, placebo-controlled trial, carvedilol, a nonselective beta-blocking and vasodilating agent was studied in six patients with chronic stable angina. All patients had reproducible treadmill exercise time without medical treatment and developed chest pain in association with ST-segment depression (greater than 1 mm at J + 80 msec) on exercise. None had a history of rest or unstable angina or myocardial infarction within three months prior to the study. In all patients, anti-anginal medication except sublingual nitroglycerin was discontinued for 10 days. The patients entered an initial two week-phase of placebo. They then received carvedilol, 25 mg and then 50 mg twice daily for two weeks on each dose, followed by another two week-placebo-phase. Radionuclide ventriculography was performed at the end of each phase at rest and during maximal symptom-limited exercise. Bicycle ergometry was carried out in the supine position with incremental workloads. Exercise time and workload were recorded at the end of the first phase and imaging was performed at the same time and workload throughout the trial. Carvedilol produced a dose-related reduction in rest and exercise heart rate and blood pressure. Peak exercise ST-segment change was reduced by both doses of carvedilol, but this did not achieve a level of significance. After the first placebo phase all patients had abnormal left ventricular wall motion and resting ejection fraction (range: 35% to 45%). Four out of six patients had significant improvement in wall motion abnormalities, in two patients there was no change, and none developed a deterioration in abnormal wall motion.(ABSTRACT TRUNCATED AT 250 WORDS)