Abstract 2909: Determinants of Mitral Regurgitation Severity in Chronic Systolic Heart Failure. A Longitudinal and Radial Strain and Strain Rate Echocardiographic Study in 90 Consecutive Patients
Background: Mitral regurgitation (MR) is a common finding in patients with left ventricular ( LV ) systolic dysfunction and is an independent predictor of mortality. Defining determinants remains challenging but is of crucial importance to guide treatment.
Purpose: Assessment of the relative influence of myocardial contractilities (radial and longitudinal) and dyssynchrony on MR-severity
Methods: 91 consecutive patients referred for evaluation of their chronic heart failure (CHF) were studied by echocardiography. We measured LV volumes, diameters and geometry, left atrial and mitral annulus sizes, mitral valve tenting. We estimated filling pressures (E/Ea, E/Vp) and, myocardial contractility and dyssynchrony using a regional strain (myocardial deformation dependant in filling pressure) and strain rate (myocardial deformation independant of filling pressure) analysis with the 2D-strain software. MR was quantified using the continuity equation and the PISA method.
Results: Table 1⇓ displays the main parameters measured. In the bivariate regression analysis, the MR regurgitant volume was correlated with mitral annulus diameter (p<0.001), LV volumes (p=0.004), estimated filling pressures (E/Ea, p=0.003). But MR regurgitation volume was also correlated with longitudinal strain of mid antero-lateral LV myocardial segment and its delays to EKG Q-wave (p<0.01). It did not with radial strain. This myocardial contractility importance on the MR-severity was influenced by filling pressure as correlations with longitudinal and radial strain rates were not significant.
Conclusion: MR in CHF-patients is multifactorial. Its echocardiographic evaluation has to be exhaustive. Dyssynchrony and longitudinal contractility in regard to the antero-lateral papillary muscle are determinant factors, potentially relevant in the therapeutic decision making. However we did not find any impact of radial contractility on MR-severity.