The influence of beta-adrenoceptor antagonists with and without intrinsic sympathomimetic activity on local wall motion abnormalities in patients with coronary heart disease.

1 A single-blind randomized study of the effects of a beta-adrenoceptor antagonist with intrinsic sympathomimetic activity (pindolol 0.4 mg i.v., n = 10) and a drug lacking this property (metoprolol 5 mg i.v., n = 11) on local wall motion abnormalities was carried out in 21 patients with coronary heart disease and anterior wall hypokinesia. 2 The drugs produced similar changes in left ventricular end diastolic pressure (LVEDP) and end diastolic volume index (EDVI) but differed in their effects on heart rate and ejection fraction. Pindolol did not exert any marked effect on heart rate or ejection fraction whereas after metoprolol treatment both were significantly decreased. 3 Shortening of the hypokinetic wall segments was improved by both drugs. Shortening of the non-hypokinetic contralateral segments was unchanged after pindolol administration but was decreased after metoprolol. 4 The differing effects of beta-adrenoceptor antagonists on regional wall motion appear to be dependent on the presence or absence of intrinsic sympathomimetic activity.