Madigan J D, Barbone A, Choudhri A F, Morales D L, Cai B, Oz M C, Burkhoff D
Departments of Medicine and Surgery, Columbia University, Black Building 812, 650 West 168th Street, New York, NY 10032, USA.
J Thorac Cardiovasc Surg. 2001 May;121(5):902-8. doi: 10.1067/mtc.2001.112632.
Support with a left ventricular assist device leads to normalization of left ventricular chamber geometry, regression of myocyte hypertrophy, alterations in left ventricular collagen content, and normalized expression of genes involved with excitation-contraction coupling in patients with heart failure. The objective of this study was to investigate the time course of these processes.
Passive left ventricular pressure-volume relationships were obtained from explanted hearts of 19 patients with heart failure undergoing transplantation without left ventricular assist device support, 25 patients with heart failure supported before transplantation (duration of support ranging between 8 and 155 days), and 5 normal human hearts not suitable for transplantation. Left ventricular size was indexed by the volume at which left ventricular pressure reached 30 mm Hg. Left ventricular tissue samples were probed for sarcoplasmic endoreticular calcium adenosine triphosphatase 2a expression and processed for analysis of myocyte diameter and relative myocardial collagen content.
The volume at which left ventricular pressure reached 30 mm Hg was not significantly different between hearts without and with assist device support for less than 40 days. However, the volume at which left ventricular pressure reached 30 mm Hg in patients with assist devices supported for more than 40 days was significantly smaller than that of the hearts without assist devices but was larger than that of normal hearts. A similar pattern was observed for myocyte diameter. Sarcoplasmic endoreticular calcium adenosine triphosphatase 2a expression increased to normal levels by about 20 days of support with an assist device. Relative collagen content was significantly increased in hearts supported for more than 40 days.
Maximum structural reverse remodeling by left ventricular assist devices is complete by about 40 days. Molecular reverse remodeling of sarcoplasmic endoreticular calcium adenosine triphosphatase 2a expression is quicker, being complete by about 20 days.
对于心力衰竭患者，使用左心室辅助装置可使左心室腔几何形态正常化、心肌细胞肥大消退、左心室胶原含量改变，并使参与兴奋 - 收缩偶联的基因表达正常化。本研究的目的是调查这些过程的时间进程。
从19例接受移植但未使用左心室辅助装置支持的心力衰竭患者、25例移植前接受支持（支持时间为8至155天）的心力衰竭患者以及5例不适合移植的正常人心的离体心脏中获取被动左心室压力 - 容积关系。左心室大小以左心室压力达到30 mmHg时的容积为指标。对左心室组织样本进行肌浆网钙腺苷三磷酸酶2a表达检测，并进行处理以分析心肌细胞直径和相对心肌胶原含量。
在支持时间少于40天的情况下，未使用辅助装置和使用辅助装置的心脏之间，左心室压力达到30 mmHg时的容积无显著差异。然而，支持时间超过40天的使用辅助装置患者，其左心室压力达到30 mmHg时的容积显著小于未使用辅助装置的心脏，但大于正常心脏。心肌细胞直径也观察到类似模式。使用辅助装置支持约20天时，肌浆网钙腺苷三磷酸酶2a表达增加至正常水平。支持时间超过40天的心脏中，相对胶原含量显著增加。
左心室辅助装置引起的最大结构逆向重塑在约40天时完成。肌浆网钙腺苷三磷酸酶2a表达的分子逆向重塑更快，约20天时完成。
