发布日期：1992-05
英文标题：Force-frequency relationship and inotropic stimulation in the nonfailing and failing human myocardium: implications for the medical treatment of heart failure.
作者：Böhm M, La Rosée K, Schmidt U, Schulz C, Schwinger RH, Erdmann E.
出处：Clin Investig. 1992 May;70(5):421-5.
内容介绍：一项体外基础研究对分别来源于扩张型心肌病伴严重心力衰竭患者心脏和正常供体心脏的离体乳头肌组织进行不同频率刺激，以模拟不同心率水平，观察心肌收缩力与刺激频率之间的关系。结果显示在基线、低浓度乌本苷、或低浓度异丙肾上腺素条件下，随着刺激频率在一定范围内的增加（即心率增快），正常心肌收缩力逐渐增加，而心衰心肌收缩力逐渐下降。研究结论：正常心肌组织的收缩力随着刺激频率的加快而增强，而病变心肌组织的收缩力随着刺激频率的加快而减弱。本研究的结果对临床治疗的启示在于证实了单纯降低心率对心力衰竭治疗的有效性：较慢的心率除了可减少衰竭心脏的能量消耗外，还可以避免因心率增快导致的心肌收缩力下降。因此，降低心率以改善心肌收缩力将有望成为心力衰竭的一种有效治疗手段。
摘要展示：
Abstract : In isolated papillary muscle strips from nonfailing donor hearts (NF) and from the hearts of patients with dilated cardiomyopathy with severe heart failure (NYHA IV), the force-frequency relationship was studied. Experiments were performed under basal conditions and in the presence of 0.01 microM or 0.1 microM isoprenaline and 0.02 microM ouabain. In NF, there was a positive inotropic effect following an increase of the stimulating frequency, whereas in NYHA IV, the force gradually declined under these conditions. Low concentrations (0.01 microM) of isoprenaline prevented the negative inotropic effect in NYHA IV, whereas at 0.1 microM the mechanical function deteriorated in NF and NYHA IV. Ouabain had no effect on the force-frequency relationship compared to basal conditions. It is concluded that a reduction of high frequencies does improve the contractility in the failing myocardium. It is not unreasonable to speculate that this mechanism might be involved in the beneficial effects of drugs which reduce the heart rate, such as beta-adrenoceptor antagonists and cardiac glycosides, in the condition of congestive heart failure in which the sympathetic tone is high.
