Iwano Hiroyuki, Pu Min, Upadhya Bharathi, Meyers Brett, Vlachos Pavlos, Little William C
Division of Cardiology, University of Mississippi Medical Center, Jackson, Mississippi, USA.
Cardiology Section, Wake Forest School of Medicine, Winston-Salem, North California, USA.
Physiol Rep. 2014 Jul 16;2(7). doi: 10.14814/phy2.12082. Print 2014 Jul 1.
The effect of diastolic dysfunction (DD) on the timing of left ventricular (LV) diastolic longitudinal and circumferential expansion and their load dependence is not known. This study evaluated the timing of the peak early diastolic LV inflow velocity (E), mitral annular velocity (e'), and longitudinal and circumferential global strain rates (SRE) in 161 patients in sinus rhythm. The intraventricular pressure difference (IVPD) from the left atrium to the LV apex was obtained using color M-mode Doppler data to integrate the Euler equation. The diastolic function was graded according to the guidelines. In normals (N = 57), E, e', longitudinal SRE, and circumferential SRE occurred nearly simultaneously during the IVPD. With DD (N = 104), e' and longitudinal SRE were delayed occurring after the IVPD (e': 18 ± 23 msec, longitudinal SRE: 13 ± 21 msec from the IVPD), whereas circumferential SRE (-8 ± 28 msec) and E (-2 ± 13 msec) were not delayed. The normal dependence of e' and longitudinal SRE on IVPD was reduced in DD; while the relation of circumferential SRE and E to IVPD were unchanged in DD. Thus, normally, the LV expands symmetrically during early diastole and both longitudinal and circumferential expansions are related to the IVPD. With DD, early diastolic longitudinal LV expansion is delayed, occurring after the IVPD and LV filling, resulting in their relative independence from the IVPD. In contrast, with DD, circumferential SRE and mitral inflow are not delayed and their normal relation to the IVPD is unchanged.
舒张功能障碍（DD）对左心室（LV）舒张期纵向和圆周扩展的时间及其负荷依赖性的影响尚不清楚。本研究评估了161例窦性心律患者左心室舒张早期峰值流入速度（E）、二尖瓣环速度（e'）以及纵向和圆周整体应变率（SRE）的时间。利用彩色M型多普勒数据整合欧拉方程，获得从左心房到左心室心尖的室内压差（IVPD）。根据指南对舒张功能进行分级。在正常组（N = 57）中，E、e'、纵向SRE和圆周SRE在IVPD期间几乎同时出现。在DD组（N = 104）中，e'和纵向SRE延迟出现，发生在IVPD之后（e'：距IVPD 18±23毫秒，纵向SRE：距IVPD 13±21毫秒），而圆周SRE（-8±28毫秒）和E（-2±13毫秒）未延迟。DD组中e'和纵向SRE对IVPD的正常依赖性降低；而DD组中圆周SRE和E与IVPD的关系未改变。因此，正常情况下，左心室在舒张早期对称扩展，纵向和圆周扩展均与IVPD相关。在DD时，左心室舒张早期纵向扩展延迟，发生在IVPD和左心室充盈之后，导致它们与IVPD相对独立。相比之下，在DD时，圆周SRE和二尖瓣血流未延迟，它们与IVPD的正常关系未改变。
