隐匿梗阻性肥厚型心肌病患者左心室扭转功能改变的超声心动图研究

An echocardiographic study of left ventricular torsion in patients with latent obstructive hypertrophic cardiomyopathy

目的探讨隐匿梗阻性肥厚型心肌病(HCM)患者左心室扭转功能的改变,为临床心功能的评估提供定量信息。方法连续纳入静息状态下无左室流出道梗阻的HCM患者49例,所有受试者均行运动负荷超声心动图检查。运动后左室流出道最大压差(LVOT-PG)≥30 mmHg为运动负荷试验(+)即隐匿性梗阻,运动后LVOT-PG<30 mmHg为运动负荷试验(-)即非梗阻。超声诊断仪获得静息及运动达峰期二维超声图像,脱机分析左室16节段二维整体纵向峰值应变(GLS)、整体圆周峰值应变(GCS)、整体径向峰值应变(GRS)以及左心室旋转(Rotation)、扭转(Twist)等参数。比较两组患者之间上述参数的差异。结果两组GLS、GCS、GRS以及基底部旋转角度(Rotation-B)在静息期及运动达峰期差异无统计学意义(均P>0.05)。与运动前比较,两组GRS显著增加(均P<0.05);与运动负荷试验(-)组比较,运动负荷试验(+)组在静息期和运动达峰期心尖部旋转角度(Ration-A)以及左心室Twist显著增高(均P<0.05);与运动前比较,运动负荷试验(+)组Rotation-A和左心室Twist显著减低(均P<0.05),运动负荷试验(-)组运动前后Rotation-A和左心室Twist无显著改变(均P>0.05)。结论隐匿梗阻性HCM患者在静息和运动后左心室扭转功能发生了显著改变,可为临床全面评估心功能提供有价值的定量信息。

Objective To explore the changes of left ventricular torsion function in patients with latent obstructive hypertrophic cardiomyopathy(HCM), and provide quantitative informations for clinical evaluation of cardiac function. Methods A total of 49 consecutive patients with HCM without left ventricular outflow tract obstruction at rest were enrolled.All subjects underwent exercise stress echocardiography. After exercise left ventricular outflow tract pressure gradient(LVOT-PG)≥30 mmHg was positive for exercise stress test (latent obstruction), while LVOT-PG<30 mmHg was negative for exercise stress test (non-obstruction). An ultrasound system obtained two-dimensional ultrasound images of resting and moving peaks. The global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS) of the left ventricle 16 segments and left ventricular rotation, twist were analysis using off-line EchoPAC software. The differences of the above parameters were compared between the two groups. Results There were no significant differences in GLS, GRS, GCS and Rotation-B between the two groups in resting and peak period of exercise (all P>0.05), GRS in both groups were significantly increased compared with that before exercise (all P<0.05). Compared with the negative exercise stress group, the left ventricular twist and Rotation-A were significantly increased in resting and peak period of exercise in the positive exercise stress test group(all P<0.05). Compared with before exercise, Rotation-A and left ventricular twist were significantly decreased in the positive exercise stress test group (all P<0.05), while no significantly difference was found in the negative exercise stress group (all P>0.05). Conclusions Left ventricular torsion function is significantly changed in rest and after exercise in latent obstructive HCM patients, providing valuable quantitative information for clinical comprehensive evaluation of cardiac function.