心肌做功联合运动负荷评估非梗阻性肥厚型心肌病左室收缩储备功能

Evaluation of left ventricular systolic function reserve in patients with non-obstructive hypertrophic cardiomyopathy using myocardial work combined with exercise stress echocardiography

目的:应用无创左心室压力-应变环(LVPSL)定量评估非梗阻性肥厚型心肌病(NHCM)患者蹲起负荷试验前后左室心肌做功变化,为临床左室收缩储备功能的评估、制定个体化运动处方提供参考。方法:选取2022年1月至2023年12月温州医科大学附属第一医院经超声心动图明确诊断的37例NHCM患者。测量并比较蹲起负荷试验前后左心室整体长轴应变(LVGLS)及心肌做功参数,分析心肌做功参数与LVGLS的相关性。结果:负荷组较静息组收缩压升高,差异有统计学意义(P<0.05),左室射血分数增高值差异无统计学意义(P>0.05)。负荷组较静息组整体LVGLS绝对值、整体有效功(GCW)、整体无效功(GWW)增加,差异均有统计学意义(P<0.05),整体做功指数(GWI)、整体做功效率(GWE)减低,差异均无统计学意义(P>0.05)。静息状态下,GWI、GCW、GWE与LVGLS呈正相关,GWW与LVGLS呈负相关;负荷状态下,GWI、GCW、GWE与LVGLS呈正相关。心肌做功参数观察者内、观察者间重复性较好。结论:运动负荷后,LVGLS仅轻微升高,GCW显著升高,LVPSL联合运动负荷超声心动图可作为NHCM患者评估心功能储备更敏感的指标。

Objective:To quantitatively evaluate the changes of left ventricular myocardial work before and after Squatting-Rising loading test in patients with non-obstructive hypertrophic cardiomyopathy(NHCM)by using noninvasive left ventricular pressure-strain loop(LVPSL),providing reference for clinical evaluation of left ventricular contractile reserve function,and individualized exercise guidance.Methods:A prospective analysis was made of 37 non-obstructive hypertrophic cardiomyopathy patients diagnosed by echocardiography in the First Affiliated Hospital of Wenzhou Medical University from January 2022 to December 2023.LVGLS and myocardial work parameters were estimated before and after Squatting-Rising loading test,and the relationship between LVGLS and myocardial work parameters was analyzed.Results:During the afterload-elevation,systolic blood pressure increased by(18±13)mmHg(P<0.01),followed by a slight increase in LVEF from(65.09%±4.91%)to(66.01%±4.92%)(P>0.05).There was a significant increase in LVGLS,GCW and GWW following the loading test(P<0.05).However,there were no significant differences in GWI and GWE before and after loading test.Furthermore,LVGLS was positively correlated with GWI,GCW,and GWE(P<0.05),while negatively correlated with GWW(P<0.05)during rest.After loading text,LVGLS was positively correlated with GWI,GCW,and GWE(P<0.05),but not correlated with GWW.The repeatability of myocardial work parameters was better in both groups.Conclusion:This study demonstrated that a modest increase in afterload can result in slight increase in LVGLS and significant increase in GCW,LVPSL combined with exercise stress echocardiography provides a more sensitive assessment on the measurement of myocardial reserve in NHCM patients.