RT Journal Article SR Electronic T1 Effects of long-term treatment with carvedilol on myocardial blood flow in idiopathic dilated cardiomyopathy JF Heart JO Heart FD BMJ Publishing Group Ltd and British Cardiovascular Society SP 808 OP 813 DO 10.1136/hrt.2006.095208 VO 93 IS 7 A1 Neglia, Danilo A1 De Maria, Renata A1 Masi, Stefano A1 Gallopin, Michela A1 Pisani, Patrizia A1 Pardini, Silvia A1 Gavazzi, Antonello A1 L’Abbate, Antonio A1 Parodi, Oberdan YR 2007 UL http://heart.bmj.com/content/93/7/808.abstract AB Objective: To assess whether chronic treatment with carvedilol can increase myocardial blood flow (MBF) and MBF reserve in idiopathic dilated cardiomyopathy (IDC). Study design: In a double-blind, placebo-controlled trial, 16 consecutive patients with IDC were randomised to treatment with either carvedilol up to 25 mg twice a day (n = 8, 7 men, mean (SD) age 60 (9) years, mean (SD) left ventricular ejection fraction (LVEF) 30% (5%)), or placebo (n = 8, 6 men, mean (SD) age 62 (9) years, mean (SD) LVEF 28% (6%), NS vs carvedilol group). Before and 6 months after treatment, regional MBF was measured at rest and after intravenous injection of dipyridamole (Dip; 0.56 mg/kg in 4 min) by positron emission tomography and using 13N-ammonia as a flow tracer. Exercise capacity was assessed as the time duration in a maximal bicycle exercise stress test. Results: Carvedilol induced a significant decrease in heart rate at rest and during maximal exercise, and an increase in exercise capacity. Absolute MBF values did not significantly change after carvedilol or placebo treatment, either at rest or during Dip injection, although Dip-MBF tended to improve after treatment. Coronary flow reserve significantly increased following carvedilol treatment (from 1.67 (0.63) to 2.58 (1.04), p<0.001), whereas it remained unchanged following the placebo treatment (from 1.80 (0.84) to 1.77 (0.60), NS). Stress-induced regional perfusion defects decreased after carvedilol treatment (from 38% to 15%). Conclusions: Long-term treatment with carvedilol can significantly increase coronary flow reserve and reduce the occurrence of stress-induced perfusion defects, suggesting a favourable effect of the drug on coronary microvascular function in patients with IDC.