健康男性运动前后心脏功能适应性变化的昼夜差异

Echocardiographic study on the diurnal changes of the exercise adaptability of cardiac function in healthy men with different ages

目的通过左心室压力应变环等技术分析不同年龄健康男性运动干预前后心脏超声相关参数变化,揭示不同年龄健康男性心脏功能运动适应性的昼夜变化特征。方法采用前瞻性对照设计,收集2022年10月至2023年7月唐都医院健康男性志愿者193例,包括青年组101例,年龄(26±5)岁,中年组92例,年龄(50±4)岁。采用3 min台阶测试,分别于清晨7点及夜晚10点采集受检者静息及负荷后心率、血压、常规超声心动图指标[左心房前后径(LAD)、二尖瓣口舒张早期血流峰值流速与舒张晚期血流峰值流速比值(E/A)、左心室射血分数(LVEF)、左心室舒张末内径(LVEDD)、左心室收缩末内径(LVEDS)],通过左心室压力应变环技术获取心肌做功参数[左心室长轴应变(GLS)、整体做功指数(GWI)、整体做功效率(GWE)、整体有效做功(GCW)、整体无效做功(GWW)]。计算以上参数变化率。比较台阶测试前后、清晨与夜晚、中年组与青年组以上参数的差异。结果青、中年健康男性清晨及夜晚台阶试验后心率、血压、心排出量显著升高(均P<0.05),GLS、GWI、GCW、GWW显著大于静息状态(均P<0.05),GWE显著小于静息状态(P<0.05);各组清晨心率、心排出量、GLS、GWI、GCW变化率显著大于夜晚(均P<0.05),而血压、GWE变化率显著小于夜晚(均P<0.05);中年组心率、收缩压、GLS、GWI在清晨及夜间变化率显著大于青年组(均P<0.05),舒张压夜晚变化率显著大于青年组(P<0.05),而晨间差异无统计学意义(P>0.05)。结论健康男性心脏超声参数具有明显的昼夜节律性变化。年龄主要影响晨间心脏超声参数变化,随年龄增长,对低强度运动干预刺激的反应增大,提示晨间心脏运动适应性降低。

Objective To reveal the diurnal variation characteristics of the exercise adaptability of cardiac function in healthy men of different ages by the analysis of echocardiographic parameter changes before and after exercise intervention using the left ventricular pressure-strain loop techniques.Methods A prospective control design was used to collect 193 healthy male volunteers from October 2022 to July 2023 in Tangdu Hospital,101 in the young group[(26±5)years old],and 92 in the middle-aged group[(50±4)years old].The heart rate,blood pressure and routine echocardiographic parameters were collected at rest and after exercise stress(3-minute step test)at 7∶00 a.m.and 10∶00 p.m.,respectively.The heart rate,blood pressure cardiac output,and echocardiographic parameters[anteroposterior diameter of left atrium(LAD),ratio of peak early diastolic flow velocity to late diastolic peak flow velocity of mitral valve(E/A),left ventricular ejection fraction(LVEF),left ventricular end diastolic diameter(LVEDD),left ventricular end systolic diameter(LVEDS)]were then determined.The parameters of myocardial work including left ventricular longitudinal strain(GLS),global work index(GWI),global work efficiency(GWE),global constructive work(GCW)and global wasted work(GWW)were obtained by left ventricular pressure-strain loop technique.The differences of the parameters above between before and after step test,morning and night,young group and middle-aged group were compared.Results The heart rate,blood pressure and cardiac output of young and middle-aged healthy men increased significantly in the morning and night step test(all P<0.05),GLS,GWI,GCW and GWW were significantly higher than those in resting state(all P<0.05),and GWE was significantly lower than that in resting state(P<0.05).The change rates of heart rate,cardiac output,GLS,GWI and GCW in the early morning were significantly higher than those at night(all P<0.05),while the change rates of blood pressure and GWE in each group were significantly lower than those at night(P<0.05).The change rates of heart rate,systolic blood pressure,GLS and GWI in the middle-aged group were significantly higher than those in the young group in the morning and night(all P<0.05),while the change rate of diastolic blood pressure at night was significantly higher than that in the young group(P<0.05),but there was no significant difference in the morning(P>0.05).Conclusions The cardiac adaptability of healthy men has obvious circadian rhythm,characterized by being of low in the morning and high in the evening.Age mainly affects the cardiac adaptability in the morning.The response to low-intensity load stimulation increases with aging,indicating the decrease of morning cardiac adaptability.