A Study Of The Application Of Speckle Tracking Strain Imaging To Cardiac Resynchronization Therapy

PART one Assessment of short-term effect of cardiac resynchronization therapy by Speckle Tracking Strain ImagingObjective To evaluate Speckle Tracking Strain Imaging(STI) in the assessment of short-term effect of cardiac resynchronization therapy(CRT). Methods 16 chronic heart failure patients(CHF)with CRT were enrolled. The time to peak systolic longitudinal strain and the time to peak systolic radial strain were derived from the LV apical views , and to peak systolic circumferential strain was derived from the parasternal short axis. The standard deviation for time to peak longitudinal,circumferential and radial strain in the 18 segments (LS-SD18,CS-SD18,RS-SD18) and the maximal temporal difference of any two segments(LS-dif,CS-dif,RS-dif)were calculated as a strain-derived dyssynchrony index. The difference of LS-SD18,CS-SD18,RS-SD18 between 1 month,3 months after CRT and baseline(â–³LS-SD18,â–³CS-SD18,â–³RS-SD18)was calculated. Analyze the correlation betweenâ–³LS-SD18,â–³CS-SD18,â–³RS-SD18 and the reduction of end-systolic volume at follow-up(â–³ESV%). Results The LS-SD18,RS-SD18,CS-SD18 and RS-dif were decreased significantly 1 month,3 months after CRT.â–³RS-SD18 was correlated withâ–³ESV% 3 months after CRT(r=0.694). Conclusions The strain-derived dyssynchrony index is great significant for short-term effect of CRT.PART two Quantitative evaluation of short-term effect of cardiac resynchronization therapy by using automated motion tracking of mitral annular displacementObjective To evaluate the tissue motion tracking of mitral annular displacement (TMAD) method in the assessment of short-term effect of cardiac resynchronization therapy(CRT). Methods Twenty six chronic heart failure patients(CHF) with CRT were detected by using TMAD. The maximal displacement of the six points of mitral annulus(DS),the standard deviation of the time to regional peak systolic displacement of the six points (Td-sd) and the maximal temporal difference of any two points(Tds-diff) were compared before and one month after one month. And the correlation between mean displacement and LVEF,ESV,FAC was analyzed. Results Compared with the pre-operatively, the displacement and the mean displacement of the six points of mitral annulus were significantly increased(P<0.01),Tds-diff and Td-sd were decreased(p<0.05) one month after CRT. TMAD correlated with biplane EF,ESV,FAC (r=0.419,r=0.529,r=0.567,P<0.05) one month after CRT. Conclusions TMAD is a new technology to evaluate the short- term effect of CRT. PART three Assessment of left ventricular torsion change of patient with heart failure after cardiac resynchronization therapy by using speckle tracking imagingObjective To evaluate the relationship between left ventricular torsion and left ventricular systolic function in patient with heart failure(CHF)after cardiac resynchronization therapy ( CRT ) by speckle tracking imaging(STI). Methods Two-dimensional echocardiographic images were acquired from the left ventricular short-axis views at the basal level and apical level of the left ventricle in 18 CHF patients. Left ventricular basal peak rotation(Rot-B) and apical peak rotation(Rot-A) were measured at each level by STI. The difference of Rot-B,Rot-A left ventricular torsion( LVtor) between 3 months after CRT and baseline(â–³Rot-B,â–³Rot-A,â–³LVtor) were calculated. The correlation betweenâ–³Rot-B,â–³Rot-A,â–³LVtor and the increase of Ejection fraction(â–³EF)were analyzed. Results Rot-A and LVtor were increased significantly in 3 months after CRT.â–³LVtor andâ–³Rot-A were correlated positively withâ–³EF(r=0. 619 , r = 0. 592). Conclusion Left ventricular systolic torsion is a novel means for assessment of the ventricular systolic function in patients with CRT.