Research on biomechanical mechanism of left ventricular rotation and twist in adults using ultrasonic velocity vector imaging
10.3760/cma.j.issn.1004-4477.2009.12.001
- VernacularTitle:成人心脏扭转运动生物力学机制的超声速度矢量成像研究
- Author:
Jing LU
;
Lixue YIN
;
Zhigang WANG
- Publication Type:Journal Article
- Keywords:
Echocardiography;
Ventricular function,left;
Torsion;
Velocity vector imaging
- From:
Chinese Journal of Ultrasonography
2009;18(12):1013-1017
- CountryChina
- Language:Chinese
-
Abstract:
Objective To evaluate the characteristic of left ventricular rotation and twist in healthy adults using ultrasonic velocity vector imaging(VVI),and to discuss its biomechanical mechanism. Methods In 70 healthy adults, the rotational characteristic of left ventricular subendocardium and subepicardium at 3 differently standard shot-axis levels and 18 differently myocardial segments, and the torsional characteristic of left ventricular wall were evaluated via ultrasonic VVI. The maximum rotation angle(Rmax)at different sites of left ventricular wall and the maximum twist angle(Tmax)between left ventricular subendocardium and subepicardium in a completely cardiac cycle were compared respectively. Correlation tests were performed between left ventricular Tmax and the Rmax at different short-axis levels of left ventricular wall.Results ①To be compared with other myocardial segments, Rmax was smallest at antero-septal or anterior wall of the same left ventricular short-axis level(P>0.05).②The mainly rotational directions of the basal leveI and the apical level of left ventricular wall in a completely cardiac cycle were adverse.To be compared with basal or apical level of left ventricular wall,Rmax was smallest at papillary muscle level(P<0.05).and there was no statistical significance in Rmax between basal and apical level.There was positive colinearity between left ventricular Tmax and the Rmax of basal or apical level (P<0.01),but zero correlation was found between the Tmax and the Rmax of papillary muscle level.③Rmax of left ventricular subendocardium was bigger than that of subepicardium(P<0.01).Tmax of left ventricular subendocardium was bigger than that of subepicardium[(11.44±4.82)°vs(7.05±3.90)±,P<0.01].Conclusions Twist of left ventricular wall in healthy adults appeared the torsional characteristic of thin-wall cylinder.Elucidation of the biomechanical mechanism of cardiac twist is promising if basing on the principle of biomechanics.