INTRODUCTION:
Right ventricular (RV) dysfunction in the setting of chronic mitral
regurgitation (MR) is common and occurs as a result of intrinsic
myocardial dysfunction, maladaptive left ventricular (LV) remodeling,
impaired ventricular septal motion, and pericardial constraint imposed
by progressive LV volume overload [1-6]. Pulmonary hypertension
secondary to severe MR exacerbates RV dysfunction by increasing RV
afterload. RV dysfunction may be further exacerbated by tricuspid valve
regurgitation (TR), which results from progressive RV and tricuspid
annular dilatation. RV dysfunction has important prognostic implications
following mitral valve surgery [7, 8], and both impaired RV function
and pulmonary hypertension are independent predictors of long-term
post-operative cardiovascular mortality [2, 3, 9-11]. Patients with
impaired RV function and significant pulmonary hypertension are
frequently excluded from conventional surgical repair but might benefit
from transcatheter mitral valve (MV) interventions. Transapical
transcatheter mitral valve implantation (TMVI) is an emerging
therapeutic alternative to conventional MV surgery for patients deemed
to be at prohibitively high risk. The objective of our study was to
examine the immediate and short-term impact of transapical TMVI using
the Tendyne mitral valve system [12, 13] on RV loading and function.