BETA-1-SELECTIVITY IS NOT ESSENTIAL TO ACHIEVE THERAPEUTIC EFFICACY WITH BETA-BLOCKADE THERAPY FOR IDIOPATHIC DILATED CARDIOMYOPATHY

This study investigated the therapeutic efficacy of two different beta -blockers, metoprolol (beta(1)-selective) and nipradilol (nonselective ) for the treatment of idiopathic dilated cardiomyopathy (DCM). The Ne w York Heart Association functional class improved in the metoprolol g roup (n = 9) and the nipradilol group (n = 9), but not in the control group who received conventional therapy (n = 8). The left ventricular ejection fraction increased in both the beta-blocker groups (p < 0.01, p < 0.05). Lymphocyte beta-adrenoceptors were upregulated in the nipr adilol group (p < 0.01). Cardiac events were less common in both the b eta-blocker groups than in the control group (both p < 0.05). Thus, ni pradilol improved symptoms and cardiac function with a favorable effec t on sympathoneuronal activity as well as metoprolol in patients with DCM. Therefore, beta(1)-selectivity is not essential to achieve therap eutic efficacy with beta-blockade therapy for DCM.