Effects of cardiac resynchronization therapy on time-domain T wave alternans in patients with chronic heart failure / 中南大学学报(医学版)

OBJECTIVE@#To study the effects of cardiac resynchronization therapy (CRT) with different pacing rates and modes on MTWA.
@*METHODS@#From March, 2012 to October, 2014, 43 patients who received CRT or CRT-D implantation in the first affiliated hospital, Nanjing Medical University were studied. Time-domain MTWA test were assessed following CRT implantation. MTWA was measured at 90 min(-1) and 110 min(-1) by treadmill exercise test with GE CASE 8000 during CRT-on (BIV biventricular) and CRT-off (RA right atrial) pacing modes. The comparsion of MTWA values between different pacing mode and pacing rates were analyzed. According to the heart function classification the patients were divided into 3 groups. The correlation between MTWA and cardiac function was analyzed.
@*RESULTS@#MTWA-AAI was significantly increased compared to MTWA-BIV at the pacing rate of 90 min(-1) [(11.27±9.94) µV vs (7.09±7.16) µV, P=0.001]. The value of MTWA at pacing rate of 110 min(-1) was nonsignificantly higher than MTWA during AAI pacing [(16.91±12.51) µV vs (15.58± 10.97) µV, P=0.517]. The value of MTWA at pacing rate of 110 min(-1) was higher than MTWA at pacing rate of 90 min(-1) during AAI or BIV (P<0.05). MTWA-AAI and MTWA-BIV in group of NYHA IV were higher than those in group of NYHA II (P<0.05).
@*CONCLUSION@#Biventricular pacing mode at lower pacing rates can significantly attenuate MTWA. The value of MTWA is associated with the severity of CHF.

Correlations of age and gender with the effects of cardiac resynchronization therapy in chronic heart failure patients / 医学研究生学报

Objective Various factors may affect the effects of cardiac resynchronization therapy or cardiac resynchronization and implantable cardioverter-defibrilator ( CRT/CRTD) in chronic heart failure patients ( CHF) .The aim of our study was to explore the correlation of age and gender with the effects of CRT/CRTD in chronic heart failure patients. Methods This study included 136 CHF patients, 92 males and 44 females, treated by CRT/CRTD from January 2005 to March 2015.We divided the patients into three age groups:≥70 yr (n=29), 50-70 yr (n=77), and 0.05).However, the CRT responding rate was remarkably higher in the female than in the male patients (66%vs 47%, P=0.027).Cox multivariate and Kaplan-Meier analyses revealed no significant differences in all-cause mortality between different genders or age groups.Multivariate logistic regression analysis showed that the left ventricular diastolic diameter and base QRS duration were independent factors of the CRT response. Conclusion Age does not affect the CRT response in chronic heart failure patients, while female patients have a higher CRT respon-ding rate than male patients.