Redwood D R, Goldstein R E, Hirshfeld J, Borer J S, Morganroth J, Morrow A G, Epstein S E
Am J Cardiol. 1979 Aug;44(2):215-20. doi: 10.1016/0002-9149(79)90307-2.
The effect of left ventriculomyotomy and myectomy on exercise capacity and cardiac function in patients with obstructive hypertrophic cardiomyopathy has not previously been determined. In this study, 29 patients were evaluated during graded treadmill exercise before and after operation. Postoperatively, 27 of 29 patients reported symptomatic improvement and had greatly reduced left ventricular outflow gradient. Twenty-five of 28 patients (89 percent) attained higher exercise levels after operation, and this was accompanied by an increase in total body oxygen consumption from 16 to 21 ml/min per kg (P less than 0.005). A significant increase in cardiac index during maximal exercise also accompanied this improved exercise performance (5.0 to 5.7 liters/min per m2, P less than 0.05). The increase in maximal cardiac index was associated with greater desaturation of mixed venous blood (34 to 24 percent, P less than 0.02) in patients with preoperative angina. At a given level of mixed venous oxygen saturation (30 percent), overall mean cardiac index was higher postoperatively (4.6 to 5.2 liters/min per m2, P less than 0.05). These results suggest that, although several mechanisms probably contribute to symptomatic improvement after myotomy and myectomy, enhanced cardiac performance plays an important role in the majority of patients.
左心室切开术和心肌切除术对梗阻性肥厚型心肌病患者运动能力和心脏功能的影响此前尚未确定。在本研究中，对29例患者在手术前后进行分级平板运动评估。术后，29例患者中有27例报告症状改善，左心室流出道梯度大幅降低。28例患者中有25例（89%）术后运动水平提高，同时全身耗氧量从16毫升/分钟每千克增加到21毫升/分钟每千克（P<0.005）。最大运动时心脏指数显著增加也伴随着运动能力的改善（从5.0升/分钟每平方米增加到5.7升/分钟每平方米，P<0.05）。术前有胸痛症状的患者，最大心脏指数的增加与混合静脉血更大程度的氧饱和度降低有关（从34%降至24%，P<0.02）。在混合静脉血氧饱和度给定水平（30%）时，术后总体平均心脏指数更高（从4.6升/分钟每平方米增加到5.2升/分钟每平方米，P<0.05）。这些结果表明，虽然可能有几种机制促成了切开术和切除术术后症状的改善，但增强的心功能在大多数患者中起着重要作用。
