CORONARY SINUS FLOW AFTER INTRACORONARY O R INTRAVENOUS ADMINISTRATION OF BISOPROLOL IN CORONARY HEART-DISEASE

Objective: To measure changes in haemodynamics and myocardial blood fl ow after acute intravenous (i.v.) and intracoronary (i.c.) injection o f bisoprolol in patients with coronary heart disease. Patients and met hods: A prospective, randomized controlled study of 14 patients (12 me n, 2 women; mean age 65 [50-73] years) with angiographically proven co ronary artery stenosis (reduced in lumen of at least 70%) in one or mo re major vessels. Seven patients received, before balloon angioplasty, either 0.01 mg/kg body weight directly into the coronaries (group 1, infusion through the guiding catheter) or 2.5 mg (group 2, via the she ath). Heart rate and blood pressure were measured before and after bis oprolol injection. Coronary blood flow was measured by the thermodilut ion method via two indwelling catheters in the coronary sinus. Results : After bisoprolol there was a reduction in heart rate (group 1: from 83/min to 75/min; group 2: from 77/min to 72/min) and blood pressure ( group 1: from 137/80 mmHg to 125/70 mmHg; group 2: from 135/86 mmHg to 126/80 mmHg). Coronary blood flow was lower after i.c. bisoprolol inj ection than before (group 1: 383 ml/min vs 352 ml/min, but higher afte r i.v. injection (group 2: 353 ml/min vs 384 ml/min). These difference s were statistically not significant. Conclusion: While after-load was clearly reduced and myocardial blood flow remained unchanged, bisopro lol improved myocardial oxygen balance. No different effects could be detected after intracoronary vs intravenous application of bisoprolol.