High Dose β-Blocker Therapy Triggers Additional Reverse Remodeling in Patients With Idiopathic Non-Ischemic Cardiomyopathy.

Carvedilol has established its evidence to improve prognosis and facilitate left ventricular reverse remodeling (LVRR) in heart failure patients with reduced left ventricular ejection fraction (LVEF), and many studies have supported its dose-dependency. However, there are few studies demonstrating the effect of high dose carvedilol in Japan. We enrolled 23 patients with idiopathic non-ischemic cardiomyopathy, in whom LVEF remained 45% or less despite 20 mg/ day of carvedilol therapy for > 3 months. After high dose (40 mg/day) carvedilol therapy for > 3 months, LVEF improved (+9.1%, P = 0.002), and LV end-diastolic diameter (LVDd) and LV end-systolic diameter (LVDs) reduced (-4.6 and -6.9 mm, respectively, P < 0.05) compared with the baseline data. Finally, 17 patients achieved LVRR after the high dose, when LVRR was defined as 1) those with final EF > 45%, and 2) those with final EF < 45% but who attained increases in LVEF > 10%, or LVEF > 5% with a decrease in LV end-diastolic dimension index (LVDDI) > 5%. Baseline predictors for LVRR after high dose carvedilol were the change rates of log B-type natriuretic peptide (BNP), LVDd, and LVDs from the time of pre-carvedilol introduction to enrollment (P < 0.05, respectively). In conclusion, high dose carvedilol triggered additional LVRR in patients with idiopathic non-ischemic cardiomyopathy and the change rates of log BNP, LVDd, and LVDs at 20 mg carvedilol may be predictors for the additional LVRR at high dose.