Relationship between entire ventricular contraction synchrony and electrocardiography in patients with chronic heart failure

Objective To observe contraction desynchronization of entire ventricle,alterations of electrocardiography and left ventricular systolic function in patients with chronic congestive heart failure in sinus rhythm.To explore the incidence of interventricular desynchronizition in patients with chronic congestive heart failure,predictive factors of interventricular dyssynchrony,and the correlation between biventricular contractile desynchronization and left ventricular function.Methods Twenty-six patients with chronic congestive heart failure and 16 control subjects were studied by standard 12-lead electrocardiography,and gated equilibrium blood pool scintigraphy.Firstly,QRS duration,P-R duration were obtained by electrocardiography.Finally,these subjects were examined by radionuclide angioscintigraphy.Left ventricular ejection fraction,right ventricular ejection fraction and other functional parameters were obtained.Phase angles and full width half the maximal on phase histogram expressed interventricular contractile synchrony were computed in sinus rhythm.Results There were significant differences between ECG parameters (QRS duration,P-R duration),(117.64±33.16) ms vs(91.87±9.16) ms,(191.43±55.25) ms vs(161.75±22.17) ms(both P0.05),phase angles of phase image analysis,(86.56±21.88)° vs(223.81±101.41)°,(26.44±8.21)° vs(57.90±42.72)°(both P0.01).In patients with heart failure,significantly negative correlation was found between phase angles and LVEF(r=-0.709,P0.001).No correlation was found between phase angles and QRS duration.In patients with heart failure,76.9% patients had interventricular contractile desynchrony.These patients also had lower left ventricular ejection fraction.In these patients,significantly negative correlation was found between phase angles and LVEF(r=-0.55,P0.05),what is more,no correlation was found between phase angles and QRS duration.Conclusion The patients with chronic heart failure have significantly abnormal electrocardiography,left ventricular systolic function,and parameters of phase image analysis.76.9% patients with heart failure had interventricular contractile dyssynchrony who had lower left ventricular ejection fraction compared with patients without interventricular contractile dyssynchrony.A significant negative correlation is found between phase angles and LVEF.This study shows that interventricular contractile desynchronization may be one of causes decreasing left ventricular function.