肥厚性心肌病心衰患者左室流出道压差和运动心肺功能研究

Study for left ventricular outflow tract gradient pressure and cardiopulmonary exercise function in patients with obstructive hypertrophic cardiomyopathy complicated heart failure

目的：通过多巴酚丁胺负荷超声心动图和心肺运动联合试验（CPET）评价左室射血分数正常的心肌肥厚病临床心衰患者左室流出道（LVOT）压差,心房大小和运动心肺功能变化。方法：对35例正常人,62例梗阻型肥厚性心肌病（HCM）心衰患者进行多巴酚丁胺负荷脉冲型,连续波型,彩色多普勒超声心动图和CPET。测定LVOT压差,左房内径,于运动前、运动高峰和运动后分别测定峰氧耗量,无氧代谢阈（AT）,每分通气量/二氧化碳排出量（.VE/.VCO2）斜率。结果：与正常人相比较,LVOT梗阻的HCM心衰组患者左室短轴缩短率[（31±9）%∶（37±11）%]明显增大、LVOT压差[静态（3.9±1.1）mmHg∶（64±36）mmHg,负荷（13±7）mmHg∶（132±34）mmHg]明显增加、左房内径[（3.0±0.6）cm∶（4.3±0.7）cm]明显增大、A峰[（55±18）cm/s∶（81±35）cm/s]明显增高,峰值耗氧量[（32±7.9）ml/kg/min∶（18.4±5.8）ml/kg/min]、无氧阈（.VO2AT）[（16.5±2.1）ml/kg/min∶（9.2±2.2）ml/kg/min]明显下降,.VE/.VCO2斜率[（25.7±4.0）∶（32.8±5.1）]显著增加,P〈0.05~0.01。结论：左室流出道梗阻型肥厚性心肌病心衰患者,心房和心肺运动功能有明显改变。负荷超声和心肺运动联合试验有助于评价梗阻型肥厚性心肌病心衰患者左室流出道压差和运动时心肺功能。

Objective： To evaluate changes of left ventricular outflow tract（LVOT） gradient pressure,size of atrium and cardiopulmonary response to exercise in patients with obstructive hypertrophic cardiomyopathy（HCM） complicated heart failure by dobutamine stress echocardiography（DSE）.Methods： DSE combine cardiopulmonary exercise test was performed in 35 normal subjects and 62 patients with obstructive HCM complicated heart failure.Results： Compared with normal subjects,left ventricular shortening fraction（LVFS） [（31±9）% vs.（37±11）%] significantly increased,LVOT gradient pressure [static（3.9±1.1）mmHg vs.（64±36） mmHg,stress（13±7） mmHg vs.（132±34） mmHg],left atrial dimension [（3.0±0.6） cm vs.（4.3±0.7） cm],A peak [（55±18） cm/s vs.（81±35） cm/s] significantly increased;peak oxygen consumption [（32±7.9） ml/kg/min vs.（18.4±5.8） ml/kg/min] and anaerobic threshold（V·O2AT）[（16.5±2.1） ml/kg/min vs.（9.2±2.2） ml/kg/min] significantly decreased;and slope of minute ventilation volume / carbon dioxide output（V·E/V·CO2）[（25.7±4.0） vs.（32.8±5.1）] significantly increased in patients with LVOT obstructive HCM complicated heart failure,P0.05~0.01.Conclusion： In patients with LVOT obstructive HCM complicated heart failure,their atrial and cardiopulmonary exercise function significantly change.Dobutamine stress echocardiography combine cardiopulmonary exercise test is useful approaches to evaluate left ventricular outflow tract obstruction,cardiopulmonary function response to exercise in such patients.