Jung I H, Seo H S, Kim M J
Inje University, Seoul, Korea Republic of.
Soonchunhyang University, Buchoen, Korea Republic of.
Eur Heart J Cardiovasc Imaging. 2016 Dec 1;17(suppl_2):ii102-ii109. doi: 10.1093/ehjci/jew248.002.
Left ventricular hypertrophy (LVH) is associated with intra-ventricular dyssynchrony at systolic phase during exercise in hypertensive patients. However, dypsnea on exertion is much more correlated with diastolic phase. We investigated whether LVH is associated with diastolic dyssynchrony during exercise in patients with hypertension.
Ninety hypertensive patients with exertional dyspnea and 30 control individuals were enrolled. Exercise stress echocardiography was performed using a symptom limited, multistage supine bicycle test. To evaluate the diastolic dyssynchrony of LV, we calculated the standard deviation (SD) of the averaged time from Q wave to myocardial early diastolic velocity in 12 segments. (TPe-SD, ms). Therefore, diastolic dyssynchrony index was SD of TPe. And also, we applied modified SD (SD/heart rate).
There was no significant difference in systolic blood pressure (BP) and heart rate between the two groups. TPe-SD was significantly higher in patients with LVH at rest (27 ± 11.0 vs. 18.7 ± 7.4 ms, p<0.005) with exaggeration of the degree at peak exercise (42.0 ± 10.6 vs. 30.6 ± 12.4 ms, p<0.001). When applying modified SD, the difference is much more increased (80.0 ± 17.6 vs. 49.0 ± 21.3 ms, p <0.001). Multiple regression analysis showed LV mass index (β=0.515, P=0.001) and E/E' at peak exercise (β= -0.253, P=0.025) were independently associated with LV dyssynchrony during diastolic phase when controlled for age, sex, and systolic BP at peak exercise.
Intra-ventricular diastolic dyssynchrony during exercise is significantly associated with exercise duration in hypertensive patients with LVH. And this result could explain that the patients with exertional dyspnea are more common in LVH group.
Univariate and multivariate analysis forUnivariate AnalysisMultivariate Analysisβp valueβp valueAge-0.2880.037-0.3550.001Sex0.1610.0200.2500.034LVMI (g/m2)-0.7870.008-0.5150.001LAVI(mL)-0.4400.065-0.1750.075E' at peak ex.0.2160.589Diastolic dyssynchrony-0.7250.030-0.2530.025S' at peak ex.0.7100.073 LVMI, left ventricular mass index; LAVI, left atrium volume index; E, early diastolic mitral inflow velocity; E', early diastolic longitudinal tissue velocity; S', early systolic longitudinal tissue velocity.
Univariate and multivariate analysis for.
LVMI, left ventricular mass index; LAVI, left atrium volume index; E, early diastolic mitral inflow velocity; E', early diastolic longitudinal tissue velocity; S', early systolic longitudinal tissue velocity.
左心室肥厚（LVH）与高血压患者运动时收缩期心室内不同步有关。然而，运动性呼吸困难与舒张期的相关性更强。我们研究了LVH是否与高血压患者运动时的舒张期不同步有关。
纳入90例有运动性呼吸困难的高血压患者和30例对照个体。采用症状限制的多级仰卧位自行车试验进行运动负荷超声心动图检查。为评估左心室的舒张期不同步，我们计算了12个节段从Q波到心肌舒张早期速度的平均时间的标准差（SD）（TPe-SD，毫秒）。因此，舒张期不同步指数为TPe的SD。此外，我们应用了修正标准差（SD/心率）。
两组间收缩压（BP）和心率无显著差异。LVH患者静息时TPe-SD显著更高（27±11.0对18.7±7.4毫秒，p<0.005），运动峰值时程度加重（42.0±10.6对30.6±12.4毫秒，p<0.001）。应用修正标准差时，差异进一步增大（80.0±17.6对49.0±21.3毫秒，p<0.001）。多因素回归分析显示，在校正年龄、性别和运动峰值时的收缩压后，左心室质量指数（β=0.515，P=0.001）和运动峰值时的E/E'（β=-0.253，P=0.025）与舒张期左心室不同步独立相关。
运动时心室内舒张期不同步与LVH高血压患者的运动持续时间显著相关。这一结果可以解释运动性呼吸困难患者在LVH组中更为常见。
单因素和多因素分析
单因素分析
多因素分析
β
p值
β
p值
年龄
-0.288*
0.037
-0.355*
0.001
性别
0.161*
0.020
0.250*
0.034
左心室质量指数（g/m2）
-0.787*
0.008
-0.515*
0.001
左心房容积指数（mL）
-0.440
0.065
-0.175
0.075
运动峰值时E'
0.216
0.589
舒张期不同步
-0.725*
0.030
-0.253*
0.025
运动峰值时S'
0.710
0.073
左心室质量指数；左心房容积指数；E，二尖瓣舒张早期血流速度；E'，舒张早期纵向组织速度；S'，收缩早期纵向组织速度。
单因素和多因素分析
左心室质量指数；左心房容积指数；E，二尖瓣舒张早期血流速度；E'，舒张早期纵向组织速度；S'，收缩早期纵向组织速度。
