EFFECTS OF SURGERY FOR HYPERTROPHIC CARDIOMYOPATHY ON EXERCISE HEMODYNAMICS

梗阻性肥厚型心肌病(间隔)的外科治疗 肌切开术/肌切开术或二尖瓣置换术)改善了许多人的症状， 但并不是所有的肥厚型心肌病患者。来评估哪一项 手术前后血流动力学的变化与 14例肥厚症患者手术后运动受益 心肌病患者接受了平板运动试验(Bruce方案)， 治疗前和治疗后6个月最大耗氧量的测定 做手术。术后锻炼研究显示锻炼效果有所改善。 持续时间，但最大含氧量仅略有改善 消费。术后最大耗氧量的改善 手术与术前研究结果直接相关。 左心室流出道流出道压差和左 室壁舒张末压力。5名患者的生活质量没有改善 最大耗氧量，包括2个大于50毫米汞梯度的 左室舒张末期减少小于5毫米汞柱 压力。9例术后最大值升高的患者中有7例 耗氧量有大于或等于65的梯度减少 毫米汞柱；梯度降低较小的2个大于8毫米汞柱 左室舒张末压降低。因此，受益于 手术后的运动能力可能与手术后的 左心室充盈压的降低幅度 手术后的坡度降低。

Surgery for obstructive hypertrophic cardiomyopathy (septal myotomy/myectomy or mitral valve replacement) improves symptoms in many, but not all patients with hypertrophic cardiomyopathy. To assess which hemodynamic changes before and following surgery best correlate with exercise benefit following surgery, 14 patients with hypertrophic cardiomyopathy underwent treadmill exercise testing (Bruce protocol) with measurement of maximum oxygen consumption before and 6 months following surgery. The post-operative exercise study demonstrated improved exercise duration but with only a marginal improvement in maximum oxygen consumption. The improvement in maximum oxygen consumption following surgery compared to the preoperative study correlated directly with the magnitude of reduction in left ventricular outflow gradient and left ventricular end-diastolic pressure. The 5 patients with no improvement in maximum oxygen consumption, including 2 with greater than 50 mmHg gradient reduction, had less than 5 mmhg reduction in left ventricular end-diastolic pressure. Seven of the 9 patients with increased post-operative maximum oxygen consumption had a gradient reduction greater than or equal to 65 mmhg; the 2 with lesser gradient reduction had greater than 8 mmhg reduction in left ventricular end-diastolic pressure. Thus, benefit in exercise capacity following surgery may be determined as much by the reduction in the left ventricular filling pressures as by the magnitude of gradient reduction following surgery.