Hasenfuss G, Holubarsch C, Hermann H P, Astheimer K, Pieske B, Just H
Medizinische Klinik III, Universität Freiburg, Germany.
Eur Heart J. 1994 Feb;15(2):164-70. doi: 10.1093/oxfordjournals.eurheartj.a060471.
In isolated human myocardium it was shown that a positive force-frequency relationship occurs in non-failing myocardium; however, the force-frequency relationship was found to be inverse in myocardium from failing human hearts. In order to investigate the clinical relevance of these experimental findings, the influence of heart rate changes on haemodynamics and left ventricular function was studied in eight patients without heart failure and in nine with failing dilated cardiomyopathy (NYHA II-III). Right ventricular pacing was performed at a rate slightly above sinus rate and at 100, 120 and 140 beats.min-1. Haemodynamic parameters were obtained by right heart catheterization and by high-fidelity left ventricular pressure measurements. Left ventricular angiography was performed at basal pacing rate and at 100 and 140 beats.min-1. With increasing heart rate, cardiac index increased in patients with normal left ventricular function from 2.9 +/- 0.2 to 3.5 +/- 0.21.min-1.m-2 (P < 0.01) and decreased continuously in patients with dilated cardiomyopathy from 2.6 +/- 0.1 to 2.2 +/- 0.1 l.min-1. m-2 (P < 0.05). With increasing heart rate, the maximum rate of left ventricular pressure rise increased in non-failing hearts from 1388 +/- 86 to 1671 +/- 88 mmHg.s-1 (P < 0.01) and did not change in failing hearts. Ejection fraction decreased from 27 +/- 3% to 19 +/- 2% in patients with dilated cardiomyopathy (P < 0.05) when the pacing rate was changed from 84 +/- 2 beats.min-1 to 140 beats.min-1, which was associated with a significant increase in end-systolic volume without significant changes in end-diastolic volume.(ABSTRACT TRUNCATED AT 250 WORDS)
在离体人心肌中发现，非衰竭心肌呈现正性力-频率关系；然而，在衰竭人心脏的心肌中，力-频率关系呈负性。为了研究这些实验结果的临床相关性，在8例无心力衰竭患者和9例患有扩张型心肌病（纽约心脏协会II-III级）的患者中，研究了心率变化对血流动力学和左心室功能的影响。通过右心室起搏，使心率略高于窦性心律，并分别维持在100、120和140次/分钟。通过右心导管检查和高保真左心室压力测量获取血流动力学参数。在基础起搏频率以及100和140次/分钟的起搏频率下进行左心室血管造影。随着心率增加，左心室功能正常的患者心脏指数从2.9±0.2增加至3.5±0.2升/分钟·平方米（P<0.01），而扩张型心肌病患者的心脏指数则持续下降，从2.6±0.1降至2.2±0.1升/分钟·平方米（P<0.05）。随着心率增加，非衰竭心脏的左心室压力最大上升速率从1388±86增加至1671±88毫米汞柱/秒（P<0.01），而衰竭心脏则无变化。当起搏频率从84±2次/分钟变为140次/分钟时，扩张型心肌病患者的射血分数从27±3%降至19±2%（P<0.05），这与收缩末期容积显著增加相关，而舒张末期容积无显著变化。（摘要截取自250字）
