Abstract 3958: Understanding “Functional” Tricuspid Regurgitation Accompanying Mitral Valve Disease
Objective: To understand the relation of degree of tricuspid regurgitation (TR) accompanying mitral valve disease (so-called “functional” TR) to both right heart (RH) dilatation (remodeling) and right ventricular (RV) function.
Methods: From 2001 to 2007, 1,833 patients with degenerative mitral valve disease, structurally normal tricuspid valves (TV), and no coronary artery disease underwent surgery. RH remodeling (RV base-to-apex length, tethering distance and area, and right atrial [RA] systolic area) and RV function (tricuspid anular plane systolic excursion [TAPSE], myocardial performance index [MPI], and TV anular shortening) were measured on preoperative transthoracic echocardiograms for 100 randomly selected patients from TR grades 0, 1+ and 2+, and for all 93 with 3+/4+. Multivariable regression was used to evaluate the association of RH remodeling and RV function with TR, adjusting for left heart measures.
Results: Increasing grade of TR was associated with higher RV pressure (P<<med>.0001), increased tethering distance (P=.008), and larger RA size (P=.0002). However, it was also associated with worsening RV function, particularly when 3+/4+ was present, such that when both TAPSE and MPI were abnormal, 3+/4+ TR was almost certain (Figure⇓). RH remodeling (tethering distance) and RV dysfunction (MPI and TAPSE) were synergistic in relation to severity of TR.
Conclusion: Although RH dilatation is associated with increasing TR, RV dysfunction is the main determinant of severe TR, indicating that TR accompanying mitral valve disease is indeed functional.