应变率成像技术评价原发性高血压飞行员左心房功能的早期改变

Strain rate imaging assessment of left atrial early function in pilots with essential hypertension

目的探讨应变率成像(SRI)技术评价原发性高血压飞行员早期左心房功能变化的价值。方法选取左心室正常构型的原发性高血压飞行员25例,以25名健康飞行员为健康对照组,行超声心动图检查并储存图像。于左心室心尖位四腔观、三腔观、二腔观应用SRI获取左心房各壁基底段、中段、上段应变率曲线,分别测量左心室收缩期、舒张早期、舒张晚期左心房峰值应变率(SRs、SRe和SRa),计算其平均值。应用二维Simpson法计算左心房最大容积(LAVmax)、左心房最小容积(LAVmin)、左心房收缩前容积(LAVp)、左心房被动射血分数(LAPEF)、左心房主动射血分数(LAAEF)和左心房搏出量(LASV)、E/A、E/E′。结果原发性高血压组LAPEF、LAAEF、LASV、E/A、E/E′分别为(38.96±6.43)%、(61.11±5.86)%、(14.74±5.33)mm、1.23±0.08、8.63±1.77,健康对照组上述指标分别为(34.18±5.72)%、(63.23±6.89)%、(10.12±3.23)mm、1.04±0.26、7.16±0.84,原发性高血压组与健康对照组比较,LAPEF、LAAEF、LASV、E/E′的差异有统计学意义(t=4.840、2.690、4.801、2.950,P均<0.05),E/A的差异无统计学意义(t=-1.424,P=0.178)。原发性高血压组患者SRa[(-2.45±0.82)s-1]与E/E′8.63±1.77呈正相关(r=0.632,P<0.05)。结论 SRI可用于早期左心房功能的评价,并在高血压病飞行员患者左心室重构发生前检侧出左心房壁形变能力降低。

Objective To assess the left atrial early function in pilots with essential hypertension by strian rate imaging （SRI）. Methods Twenty-five hypertensive pilots without left ventricular hypertrophy and expansion （LVN） were selected. Twenty-ifve healthy pilots were included as control group. At the left ventricular apical four-chamber view, three-chamber view, two-chamber view, the systolic, early and late diastolic peak strain rate （SRs, SRe, SRa） curves were acquired by SRI in the basal section, the middle section and the upper section of the wall of left atrium. The average strain rate （mSRs, mSRe, mSRa） was calculated. The LA maximal, minimal and pre-systolic volume （LAVmax , LAVmin and LAVp）, LA passive ejection fraction （LAPEF）, LA active ejection fraction （LAAEF） , left atrial stroke volume （LASV）, E/A and E/E′ were calculated. Results The LAPEF, LAAEF, LASV, E/A, E/E′were （38.96±6.43）%, （61.11±5.86）%, （14.74±5.33）mm, 1.23±0.08, 8.63±1.77 in the control group, and were （34.18±5.72）%, （63.23±6.89）%, （10.12±3.23）mm, 1.04±0.26, 7.16±0.84 in the study group. Compared with the control group, signiifcant difference was detect in LAPEF, LAAEF, LASV, E/E′（t=4.840, 2.690, 4.801, 2.950, all P〈0.05）. No signiifcant difference was found in E/A between the study and control group （t=-1.424, P=0.178）. There was signiifcant positive correlation between SRa and E/E′（r=0.632, P〈0.05）. Conclusion SRI could be applied in the evaluation of early left atrial function. In pilots with essential hypertension, the changes of strain rate in left atrial wall, which is prior to the modeling geometry of left ventricular, could be detected by SRI.