Effects Of Cardiac Resynchronization Therapy With Left Univentricular Pacing On Left Atrial Structure And Function

Objective Rsearch the effect of single left ventricular pacing(LUVP)and biventricular pacing(BVP)on cardiac resynchronization therapy(CRT),and then evaluate the effect of single left ventricular pacing(LUVP)on left atrial structure and function.Methods 30 patients with chronic heart failure who met the indications of implanting CRT in the Affiliated Hospital of Qingdao University from July 2017 to February 2019were selected,including 19 males,11 females,7 patients with ischemic cardiomyopathy and 23 patients with dilated cardiomyopathy.According to age,sex and etiology,the subjects were divided into two groups in 1:1 matching manner,including 15 patients in LUVP group and 15 patients in BVP group,and different types of pacemakers were randomly selected before operation.According to the grouping,two different CRT modes are programmed by Smart delay function,Adaptive CRT function and rate adaptive atrioventricular delay(RAAVD)function.After 6 months of follow-up,the differences between two groups were compared,including Classification of NYHA heart function,QRS duration,left atrial volume index(LAVI),left atrial ejection fraction(LAEF),left ventricular ejection fraction(LVEF),inter-ventricular mechanical delay(IVMD),septal to posterior wall mechanical delay(SPWMD),mitral regurgitation area(MRA),left ventricular end-diastolic dimension(LVEDD).SPSS 22.0 statistical software was used for statistical analysis,and P<0.05 was considered statistically significant difference.Results Compared with pre-operation,after 6 months,the BVP group showed improved Classification of NYHA heart function,decreased QRS duration(183.8±17.2ms vs141.3±8.4ms),LAVI(53.1±9.5ml/m~2 vs 47.0±7.8ml/m~2),MRA(6.0±1.2cm~2 vs3.0±1.0cm~2),LVEDD(75.1±9.2mm vs 58.3±6.0mm),IVMD(74.5±4.5ms vs43.0±9.5ms)and SPWMD(201.3±10.1ms vs 153.3±16.4ms);increased LAEF(35.9±6.3%vs 43.3±6.0%)and LVEF(26.4±6.5%vs 43.5±5.7%),the differences were statistically significant(P<0.05).Compared with pre-operation,after 6 months,the LUVP group showed improved Classification of NYHA heart function,decreased QRS duration(179.7±22.3ms vs 133.8±9.1ms),LAVI(52.8±10.0ml/m~2 vs 47.1±10.2ml/m~2),MRA(5.4±1.2cm~2 vs 1.9±1.0cm~2),LVEDD(73.3±6.7mm vs 55.0±5.5mm),IVMD(77.1±5.2ms vs 41.7±9.3ms)and SPWMD(201.9±13.1ms vs 154.6±17.6ms);increased LAEF(35.9±6.9%vs 42.5±7.2%)and LVEF(25.6±6.7%vs 43.7±5.1%),the differences were statistically significant(P<0.05).6 months after surgery,compared with the BVP group,the LUVP group showed decreased QRS duration(141.3±8.4ms vs 133.8±9.1ms)and MRA(3.0±1.0cm~2 vs 1.9±1.0cm~2),the differences were statistically significant(P<0.05).Conclusions The structure and function of left ventricle and left atrium in patients with chronic heart failure were significantly improved after CRT.While LUVP is superior to BVP in decreasing QRS duration and MRA.