比索洛尔对快速右室起搏犬心室重塑的影响

Effects of bisoprolol on ventricular remodeling induced by rapid right ventricular pacing in canine

１９条犬随机分为心脏起搏组（Ｐ，ｎ＝７），起搏加比索洛尔干预组（ＰＢ，ｎ＝６）和对照组（Ｃ，ｎ＝６）。Ｐ与ＰＢ组动物均以２５０次／分钟频率持续右室起搏４周。起搏后Ｐ组动物均出现心力衰竭表现。组织病理学显示心肌细胞浊肿，质膜水肿，肌节排列紊乱，部分肌丝溶解、断裂。ＰＢ组起搏后肺楔压升高和心排量降低幅度以及心肌病理改变程度均显著轻于Ｐ组。以上表明，比索洛尔可以减轻这一心肌病模型的心肌损害程度。

Objective: To evaluate the effects of bisoprolol on ventricular remodeling in pacing induced heart failure in dogs. Methods: 19 dogs were randomized into pacing group (P, n =7), bisoprolol intervention (PB, n =6) and control (C=6) groups respectively. All dogs in P and PB groups underwent right ventricular pacing at 250 beats/min for 4 weeks, and dogs in PB group were administered bisoprolol (2.5 mg/d) orally during the pacing period. Results: After pacing, all dogs in P group showed obvious congestive heart failure both in clinical and hemodynamic aspects. The histopathological findings included: cloudy swelling in cardiac myocytes membranous edema and sarcomere disarrangement, and myofibrils some what dissolved or disrupted. The extent of increased pulmonary wedge pressure and decreased cardiac output, as well as the pathologic abnormalities of myocardium induced by pacing in group PB were less than group P significantly. Conclusion: Bisoprolol may alleviate ventricular remodeling in pacing induced heart failure.