Monrad E S, Hess O M, Murakami T, Nonogi H, Corin W J, Krayenbuehl H P
Medical Policlinic, Division of Cardiology, University Hospital, Zurich, Switzerland.
Circulation. 1988 Jun;77(6):1345-55. doi: 10.1161/01.cir.77.6.1345.
To assess the time course and extent of regression of myocardial hypertrophy after removal of the inciting hemodynamic stress, 21 patients with either aortic stenosis or aortic insufficiency were studied preoperatively, after an intermediate period (1.6 +/- 0.5 years), and late (8.1 +/- 2.9 years) after aortic valve replacement, and results were compared with those in 11 control patients. After aortic valve replacement there was significant hemodynamic improvement, with a fall in the left ventricular end-diastolic volume index (164 +/- 73 to 105 +/- 35 ml/m2, p less than .01), a fall in left heart filling pressure (19 +/- 9 to 12 +/- 5 mm Hg, p less than .01), and maintenance of the cardiac index (3.3 +/- 0.8 to 3.5 +/- 0.8 liters/min/m2, NS) and left ventricular ejection fraction (60 +/- 13% to 64 +/- 10%, NS). By the late study the cardiac index (4.0 +/- 0.6 liters/min/m2, p less than .01) and left ventricular ejection fraction (66 +/- 15%, p less than .05) had further increased and were significantly greater than before surgery. For the group as a whole, the left ventricular muscle mass index fell 31% after surgery by the time of the intermediate postoperative study (174 +/- 38 vs 120 +/- 29 g/m2, p less than .01), and a further 13% from the intermediate to the late study (105 +/- 32 g/m2, p less than .05). At the preoperative study left ventricular muscle mass index was greatest in those patients with aortic insufficiency (191 +/- 36 g/m2), and greater in those with aortic stenosis (158 +/- 33 g/m2) than in control subjects (85 +/- 9 g/m2, p less than .05). At the intermediate postoperative study left ventricular muscle mass index remained significantly higher in both those with preoperative aortic insufficiency (128 +/- 29 g/m2) and those with stenosis (114 +/- 27 g/m2) than in the control subjects (p less than .01). By the time of the late postoperative study there were no longer any significant differences in left ventricular muscle mass index. Thus, the regression of myocardial hypertrophy is a process that occurs over many years after correction of the primary hemodynamic abnormality. As this process of myocardial remodeling occurs, continued improvement in cardiac function may occur, and the improvement occurring between the intermediate and late postoperative studies at a slight but constant afterload excess (inherent in the relative stenosis of the aortic prosthesis) suggests that the hypertrophied myocardium is operating at a reduced level compared with normal myocardium.
为评估去除激发性血流动力学应激后心肌肥厚消退的时间进程和程度，对21例主动脉瓣狭窄或主动脉瓣关闭不全患者在术前、主动脉瓣置换术后中期（1.6±0.5年）和晚期（8.1±2.9年）进行了研究，并将结果与11例对照患者进行比较。主动脉瓣置换术后血流动力学有显著改善，左心室舒张末期容积指数下降（164±73至105±35ml/m²，p＜0.01），左心充盈压下降（19±9至12±5mmHg，p＜0.01），心排血量指数维持不变（3.3±0.8至3.5±0.8升/分钟/m²，无显著性差异），左心室射血分数维持不变（60±13%至64±10%，无显著性差异）。在晚期研究时，心排血量指数（4.0±0.6升/分钟/m²，p＜0.01）和左心室射血分数（66±15%，p＜0.05）进一步升高，且显著高于手术前。对于整个组而言，术后中期研究时左心室肌肉质量指数下降了31%（174±38比120±29g/m²，p＜0.01），从中期到晚期研究又下降了13%（105±32g/m²，p＜0.05）。在术前研究中，主动脉瓣关闭不全患者的左心室肌肉质量指数最高（191±36g/m²），主动脉瓣狭窄患者的左心室肌肉质量指数（158±33g/m²）高于对照组（85±9g/m²，p＜0.05）。在术后中期研究时，术前有主动脉瓣关闭不全（128±29g/m²）和狭窄（114±27g/m²）的患者左心室肌肉质量指数仍显著高于对照组（p＜0.01）。到术后晚期研究时，左心室肌肉质量指数不再有任何显著差异。因此，心肌肥厚的消退是在纠正原发性血流动力学异常后多年发生的过程。随着心肌重塑过程的发生，心脏功能可能会持续改善，术后中期和晚期研究之间在轻微但持续的后负荷过度（主动脉人工瓣膜相对狭窄所固有的）情况下出现的改善表明，肥厚心肌的功能水平低于正常心肌。
