Determinants of Severity in Dilated Cardiomyopathy : The Gap of Tricuspid and Mitral Valve Opening

Objectives: The purpose of this study is to analyze factors that influence the gap ofopening timing between the mitral valve (MV) and the tricuspid valve (TV) inpatients with dilated cardiomyopathy (DCM).Background: The DCM patients with heart failure often show shorter left ventricular(LV) isovolumic relaxation time (IRT) and longer right ventricular (RV) IRT, whichmay influence the gap of opening timing between TV and MV.Method: We evaluated consecutive 34 patients with DCM. The time between QRSinitial and TV opening (Q-T time), and that between QRS initial and MV opening (QMtime) were measured by pulsed Doppler recording of each ventricular inflow. Thetime interval between MV and TV opening (M-T time) was determined by subtractingQ-M time from Q-T time. In addition, the other Doppler time intervals including preejectionalperiod, ejection time, IRT were determined. We analyzed the relationbetween Doppler time intervals and factors including NYHA classification and rightsidedcardiac pressure.Result: There is significant relationship (p <0.001) between M-T time and PCWP(r=0.65), and NYHA (rs=0.67), respectively. The Ll IRT determined by subtractionof LV IRT from RV IRT, correlated significantly with M-T time (r=0.83, p<O.OOl),however, the difference between LV and RV in PEP and ET did not correlatedsignificantly with M-T time.Conclusion: The gap of opening timing between TV and MV, determined as M-T time,correlates strongly with LlIRT and also the severity of congestive heart failure in DCMpatients