Predictors Of Normal Cardiac-function After Cardiac Resynchronization Therapy

Objective:To analyze the clinical features of returning normal cardiac-function after cardiac resynchronization therapy(CRT/CRT-D)in patients with heart failure.To evaluate the predictors of returning normal cardiac-function after CRT.Methods:A total numbers of 70 patients who underwent CRT/CRT-D were studied since Jan 2008 to Sep 2016 and were divided into three groups:normal cardiac-function group,abnormal cardiac-function group and reaction group.We had collected the information on patients' baseline date like age,sex,the application of drugs related heart failure,the position of left and right ventricular lead,distance between them and so on,followed up for at least 6 months.Before CRT and 6 months later,clinical and echocardiographic evaluation was performed,left ventricular end-diastolic diameter(LVEDD)and left ventricular ejection fraction(LVEF)were measured to evaluate the size and ability of ejection of the left ventricle.Data was analyzed with SPSS 21.0.When P<0.05,the difference was considered to be significant.Results:After follow-up for at least 6 months,8 patients were classified as returning normal cardiac-function after CRT.There was significant difference in true complete left bundle branch block(t-CLBBB)between normal cardiac-function group and abnormal cardiac-function group(87.5%vsl2.9%,OR=12.396,95%CI 3.106?36.595,P=0.006).There was also significant difference in true complete left bundle branch block(t-CLBBB)between normal cardiac-function group and reaction group(87.5%vsl2.9%,OR=14.383,95%CI 2.150?24.856,P=0.012).After 6 months,there were significant changes in LVEF(30.9±6.8%vs 55.6 ± 3.8%),LVEDD(61.5±5.6mm vs 48.1 ±3.8mm),QRS duration(172.5±15.7ms vs 141.5± 19.0ms)and NYHA class(3.1±0.6vs1.0±0.0)in normal cardiac function group.There were also significant changes in LVEF,QRS duration and the improvement of left ventricular end-diastolic diameter(LVEDD){(17.07±13.327 vs 4.22±3.279);(24.670±10.186 vs 11.090±5.682);(10.71±7.350 vs 3.60±1.874);P<0.05}between patients with t-CLBBB)and patients with non-t-CLBBB}.The patients with t-CLBBB have a higher survival rate(P=0.024).Conclusions:A chronic heart failure patient with true left bundle branch block is the predictor of normal cardiac-function after CRT.