Dilitiazem in Comparison with metoprolol in stable angina pectoris

The efficacy of diltiazem in comparison with metoprolol in chornicstable angina was asessted in 33 male patients during a 15-weekblind cross-over study. After an initial two-week run-in period,baseline measuremens were made. Subsequently,the patients enereda cross-over study consisting of two six-week treatment periodswith diltiazem 240 mg (60 mg q.i.d.)or metoprol 200 mg (100mg b.i.d.).Dose adjustment to either 360 mg diltiazem(120t.i.d.)or400 mg metoprolol(200b.i.d.)was allowed two weeks after thestart of treatment. There was a one-week washout period betweenthe two treatment periods. Compared to baseline values both drugs reduced the number ofanginal attacks (diltiazem –55%,p=0.02; metoprolol –73%,P=0.01)andshowed improvement of the measured exercise variables(exerciseduration; diltiazem +16%,P<0.001;meoprolol +4%,P=NS; timeto angina:diltiazem +21%,P=0.02,metoprolol + 14%, P =NS;maximalST-depression: diltiazem +13%,P =NS,metoprolol +33%,P=0.002).Nosignificant change in LVEF was noticed.Both drugs reduced themean heart rate on Holter tape (diltiazem–11%,P=0.006;metoprolol–14%, P=0.004). No effects on conduction were noticed. Although at the borderline of significance, diltiazem increasedthe total exercise duration as compared to metoprolol (16 vs,4%,P=0.05). It is concluded that diltiazem improves exercisetolerance in patients with stable angina pectoris and appearsto be a safe and effective alternative to the beta-blockingagent metoprolol.Our findings underscore the value of diltiazemas a monotherapeutic drug for the treatment of stable angina.