Clinical efficacy and predictor of cardiac resynchronization therapy on left bundle branch block-associated heart dysfunction

【摘要】 Background Left bundle branch block(LBBB)results in an altered pattern of left ventricular(LV)activation and subsequent contraction.Cardiac synchrony and cardiac function are deteriorated by LBBB.However,the effect of LBBB history on progressive heart dysfunction and clinical efficacy of cardiac resynchronization therapy(CRT)in such patients are not clear.In this study we explore the clinical efficacy and predictor of cardiac resynchronization therapy in LBBB heart dysfunction.Methods Twenty-seven LBBB patients with severe heart failure were treated with CRT.Twenty-six LBBB patients without CRT served as control.During 6 months follow-up,ECG,plasma NT-proBNP and echocardiogram indexes were measured.Results Compared with baseline,NYHA functional class of 23 patients(85.2%)was improved in CRT group.Compared with baseline and control,QRS duration(QRSd)was significantly more narrow(P=0.023,P=0.019),NT-proBNP was significantly lower(P=0.011,P=0.009),ventricular septal to left ventricular posterior wall delay time and left ventricular dyssynchrony index(Ts-SD)were significantly worse(P<0.05);left ventricular ejection fraction,left ventricular end-systolic volume,mitral regurgitation area were significantly improved in CRT group(P<0.05).when the LBBB history was≥2 years and QRSd≥155 ms,the sensitivity and specificity of CRT super-response were 53.4%and 85.6%respectively.Conclusions CRT can improve the synchronization and hemodynamic of LBBB patients with heart dysfunction,the LBBB history≥2 years and QRSd≥155 ms are one of the CRT super-response predictors.更多还原

【Abstract】 Background Left bundle branch block(LBBB) results in an altered pattern of left ventricular(LV)activation and subsequent contraction. Cardiac synchrony and cardiac function are deteriorated by LBBB.However, the effect of LBBB history on progressive heart dysfunction and clinical efficacy of cardiac resynchronization therapy(CRT) in such patients are not clear. In this study we explore the clinical efficacy and predictor of cardiac resynchronization therapy in LBBB heart dysfunction. Methods Twenty-seven LBBB patients with severe heart failure were treated with CRT. Twenty-six LBBB patients without CRT served as control. During 6 months follow-up, ECG, plasma NT-proBNP and echocardiogram indexes were measured.Results Compared with baseline, NYHA functional class of 23 patients(85.2%) was improved in CRT group. Compared with baseline and control, QRS duration(QRSd) was significantly more narrow(P =0.023, P = 0.019), NT-proBNP was significantly lower(P = 0.011,P = 0.009), ventricular septal to left ventricular posterior wall delay time and left ventricular dyssynchrony index(Ts-SD) were significantly worse(P < 0.05); left ventricular ejection fraction, left ventricular end-systolic volume, mitral regurgitation area were significantly improved in CRT group(P < 0.05). when the LBBB history was ≥ 2 years and QRSd ≥155 ms, the sensitivity and specificity of CRT super-response were 53.4% and 85.6% respectively.Conclusions CRT can improve the synchronization and hemodynamic of LBBB patients with heart dysfunction, the LBBB history≥ 2 years and QRSd ≥ 155 ms are one of the CRT super-response predictors.更多还原