Evaluating The Relationship Between Left Ventricular Twist And Systolic Synchrony In Patients With Cardiac Resynchronization Therapy Using Velocity Vector Imaging

Objectives Investigating the relationship between left ventricular twist and systolic synchrony assessed by velocity vector imaging(VVI) in order to search for the best indicator to assess mechanical synchrony and predict the short-term response of cardiac resynchronization therapy(CRT), providing valuable help for clinical diagnosis and estimation of treatment.Methods During January2011-December2012, thirty patients (20male and10female), average aged (55.57±11.67) years, twenty-six diagnosed with dilated cardiomyopathy, two with hypertensive cardiomyopathy and two with ischemia cardiomyopathy, were included in this study. All corresponded to standard CRT indications. A series of comparisons were made between the three modes, preoperative,after one month and four months, High-frame rate two-dimensional images were recorded from the left ventricular short-axis views (mitral valve level, papillary muscle level, apex level) from heart failure patients with the pacemaker implantation. Myocardial rotation was quantitatively analysed with an Acuson Sequoia512and VVI offline software and Siemens Syngo US Workplace software, simultaneously, including QRS width, mechanical synchrony parameter(TS-SD), aortic velocity time integral (AVTI), left ventricular ejection fraction (LVEF), left ventricular at the end of diastole diameter(LVEDV), left ventricle at the end of systolic diameter(LVESV) and the classifications on cardiac function of NYHA, walking distance in the six minutes, the scores of life quality. The correlation between above-mentioned parameters was analyzed using SPSS17.0statistical software, P<0.05was different, and P<0.01was a significant difference. Results1. Completive condition of CRT11CRT-P and19CRT-D were accomplished successfully, and had no critical complications. All patients finished the follow-up, in the mean time, they were given the optimal medical treatment.2. Clinical Datas After postoperative, LVEDV、LVES V and the score of life quality were significantly smaller than preoperative, simultaneously QRS was more narrow (P<0.001, at the same time, LVEF、AVTI and walking distance in the six minutes were more incremental than preoperative after the operation (P<0.001)3. Comparing with of each segment of different level①There was no statistical significance in the torsion angle of anteroseptal, infetheca postetheca at the level of mitral valve level, papillary muscle level, apex level before the operation (P>0.05), however, the torsion angle of antetheca、postetheca、 latethecahad a obvious statistical significance (P<0.001, P=0.015, P=0.05, respectively)②There was no statistical significance in the torsion angle of anteroseptal, postetheca, antetheca, septal at the level of mitral valve level, papillary muscle level, apex level after one month of operation (P>0.05), however, the torsion angle of latetheca、 infetheca had a notable statistical significance (P<0.001)③There was no statistical significance in the torsion angle of postetheca, latetheca Antetheca, septal at the level of mitral valve level, papillary muscle level, apex level after four months of operation (P>0.05), however, the torsion angle of anteroseptal、 infethecahad a prominent statistical significance (P=0.01and P=0.018, respectively).4. Comparing with the parameter of left ventricular twistIn the aspect of Par, PBr, Ptw, it was larger in systole and diastole after one month and four months of the operation, and had also notable statistical significance (P<0.01)5. Linear correlation analysis(1)the correlation between left ventricular twist and systolic synchronyIt showed a positive correlation between Ptw(SM) and Ts-12-SD (r=0.385、 P=0.039; r=0.43、 P=0.024; r=0.422、P=0.028, respectively) among preoperative, one month later, four months later.(2)the correlation analysis between the angle of left ventricular twist and LVEFIt showed a positive correlation between Ptw(SM) and LVEF (r=0.375、P=0.041; r=0.411、P=0.024; r=0.37、P=0.044, respectively) among preoperative, one month later, four months later, at the same time, the result showed that there was a linear correlation between Ptw(SM)(preoperative) and LVEF (postoperative)(r=0.379、 P=0.039; r=0.375、P=0.041, respectively).(3)the correlation analysis between the angle of left ventricular twist and electri-cal synchronyThe result showed that there was no linear correlation between Ptw(SM) and QRS width among preoperative, one month later, four months later (P>0.05)(4)the correlation analysis between mechanical synchrony and electrical synchronyThe result showed that there was no linear correlation between Ts-12-SD and QRS width among preoperative, one month later, four months later (P>0.05)Conclusions1. The paraeters of left ventricular torsion can evaluate left ventricular systolic synchrony accurately, and provide a simple evaluation method for clinical except Ts-12-SD.2. There was a linear correlation between the angle of left ventricular twist and LVEF and provide a new index for the efficacy of CRT for clinical.3.Left ventricular twist may be more superior to QRS width on left ventricular dyssynchrony.