Rousseau M F, Chapelle F, Van Eyll C, Stoleru L, Hager D, Van Nueten L, Pouleur H
Division of Cardiology, University of Louvain, School of Medicine, Brussels, Belgium.
J Card Fail. 1996 Mar;2(1):15-23. doi: 10.1016/s1071-9164(96)80004-2.
The aim of this study was to compare the effects on left ventricular function and exercise tolerance of a selective beta-antagonist (atenolol) with those of another selective beta 1-antagonist with vasodilator properties (nebivolol) in patients with ischemic left ventricular dysfunction but no overt congestive heart failure. Beta blockers are widely used in ischemic heart disease, but their effects on left ventricular mechanics and exercise tolerance are poorly defined in the subgroup of patients with significant systolic dysfunction but without clinical evidence of ischemia or congestive heart failure. Angiographic and symptom-limited exercise data were obtained at baseline and after an 8-10-week double-blind treatment with placebo (n = 10), 50 mg atenolol daily (n = 10), or 2.5 mg (n = 10) or 5 mg (n = 10) nebivolol daily. When compared to placebo, both atenolol and nebivolol reduced resting heart rate and improved left ventricular ejection fraction (from 33.9 to 39.2% with atenolol and from 36.5 to 40.8% with nebivolol, both P < .05) while lowering mean systolic wall stress. Only nebivolol, however, produced a parallel downward shift of the pressure-volume relationship during early diastolic filling and improved the early peak filling rate when compared to placebo (+ 10%, P < .05). When compared to baseline, maximal exercise duration increased by 7 and 13 seconds with placebo and atenolol, respectively (both NS vs baseline), and increased by 44 seconds with nebivolol (P = .0077 vs baseline). Both atenolol and nebivolol decreased maximal exercise heart rate; the reduction was more pronounced with atenolol. Prolonged beta 1-adrenoceptor blockade leads to a significant increase in left ventricular ejection fraction in patients with ischemic left ventricular dysfunction. The dissociation between the changes in resting left ventricular function and the changes in exercise duration suggests that in this clinical setting, the changes in systolic function may have less impact on functional capacity than an improvement in diastolic distensibility during the rapid filling phase.
本研究旨在比较选择性β受体阻滞剂（阿替洛尔）与另一种具有血管舒张特性的选择性β1受体阻滞剂（奈必洛尔）对缺血性左心室功能不全但无明显充血性心力衰竭患者左心室功能和运动耐量的影响。β受体阻滞剂广泛应用于缺血性心脏病，但在有明显收缩功能障碍但无缺血或充血性心力衰竭临床证据的患者亚组中，其对左心室力学和运动耐量的影响尚不明确。在基线时以及接受8 - 10周的安慰剂（n = 10）、每日50 mg阿替洛尔（n = 10）、或每日2.5 mg（n = 10）或5 mg（n = 10）奈必洛尔的双盲治疗后，获取了血管造影和症状限制运动数据。与安慰剂相比，阿替洛尔和奈必洛尔均降低了静息心率并改善了左心室射血分数（阿替洛尔从33.9%提高到39.2%，奈必洛尔从36.5%提高到40.8%，两者P <.05），同时降低了平均收缩期壁应力。然而，与安慰剂相比，只有奈必洛尔在舒张早期充盈期间使压力 - 容积关系平行向下移动，并改善了早期峰值充盈率（提高10%，P <.05）。与基线相比，安慰剂和阿替洛尔使最大运动持续时间分别增加了7秒和13秒（两者与基线相比均无统计学意义），而奈必洛尔使最大运动持续时间增加了44秒（与基线相比P =.0077）。阿替洛尔和奈必洛尔均降低了最大运动心率；阿替洛尔的降低更为明显。长期β1肾上腺素能受体阻滞导致缺血性左心室功能不全患者的左心室射血分数显著增加。静息左心室功能变化与运动持续时间变化之间的分离表明，在这种临床情况下，收缩功能的变化对功能能力的影响可能小于快速充盈期舒张期扩张性的改善。
