Influence Of Premature Ventricular Contractions On Left Ventricular Function And Structure In PVC Patients

Background Premature ventricular contractions(PVC)is a common arrhythmia disease in clinical practtice.The idiopathic PVC has long been regarded as one simply"benign" performance which-the risk of death had no significant difference to the general population.However,many studies of recent years found that PVC patients without underlying organic heart disease may occurred reversible ventricular remodeling,left ventricular dysfunction,or even premature ventricular contraction-induced cardiomyopathy with the development of PVC.To find the influence factors of PVC on cardiac function and structure,our study wish to explore the mechanism of premature ventricular contraction-induced cardiomyopathy,becoming a research hotspot.Objective Our study Analyzed the influences of clinical factors and electrophysiological factors such as gender,age,duration of palpitation,PVC burden,coefficient of variation(Cov)hourly and interquartile Cov in frequency of PVC,QRS duration of PVC,origin,coupling interval,non-sustained ventricular tachycardia on left ventricular function and structure.The study may provide reference for clinical treatment and prognosis of PVC.Method The subjects of this retrospective study were 197 consecutive patients,which were diagnosed PVC in the First Affiliated Hospital of Dalian Medical University from May 2015 to November 2016.All candidates didn’t have any non-ventricular arrhythmia or organic heart disease.According to left ventricular ejection fraction and left ventricular end-diastolic internal diameter,we divided the PVC patients into different groups.Then,we analyzed the difference between groups on gender,age,duration of palpitation,PVC burden and the association of these factors with left ventricular function and structure.SPSS 21.0 software was used for statistical analysis.Results(1)There was no significant difference in gender,age,duration of palpitation,origin,coupling interval,E/A,interpolation PVC and non-sustained ventricular tachycardia between groups.(2)Compared to normal LVEF,patients with reduced LVEF(25.31±11.01%vs.13.70±8.39%,P<0.001)or increased LVED(24.86±11.46%vs.15.35±9.64%,P<0.001)had an increased burden of PVC.With PVC burden increasing,LVEF decreased(58.18±2.51%vs.56.27±3.00%,P<0.001),and LVED increased(46.23±4.30%vs.48.12±4.96%,P=0.008).(3)The QRS duration of reduced LVEF group and increased LVED group are longer.LVEF became decreased as QRS duration increasing.(58.19±2.28 vs.56.70±3.11,P=0.001).(4)Patients with reduced LVEF as compared to normal LVEF,the Cov hourly(25.8%hours(20%,30.1%)vs.60.7%(46.8%,89.2%),P<0.001)and interquartile Cov(15.8%(10.6%,22.5%)vs.44.7%(31.8%,67.7%),P<0.001)were lower,increased LVED group compared to normal group,the Cov hourly(28.0%(21.1%,53.9%)vs.53.2%(36.4%,83.4%),P<0.001)and interquartile Cov(21.0%(11.3%,33.5%)vs.38.4%(23.3%,63.6%),P<0.001)were lower too.(5)After analyzed the origin of PVC,we found that the right ventricular outflow tract(RVOT)was the most common origin which accounting for 60.9%.The LVEF,LVED,E/E’ and LAV in the different sites of PVC were also compared,and there was no significant difference(P>0.05).(6)The LVEF,LVED,E/E’,LAV had no significant difference(P>0.05)between the two groups with or without non-sustained ventricular tachycardia.Conclusion In the study,with more PVC burden,QRS duration,lower Cov hourly,interquartile Cov,patients were inclined to have reduce LVEF and increase LVED.It means that,the character of PVC have clinical meaning on identify the patients who are more likely to have injury on cardiac structure or function as early as possible.