Impact of Transcatheter Aortic Valve Replacement on Left Ventricular Remodeling in Patients with Preserved Left Ventricular Function

Kyvernitakis, Andreas

Background
Aortic stenosis (AS) is a known cause of left ventricular (LV) hypertrophy and diastolic heart failure. Limited data is available regarding the impact of transcatheter aortic valve replacement (TAVR) on regression of LV hypertrophy and myocardial remodeling. In this study, we sought to investigate the impact of TAVR on diastolic function and LV remodeling by echocardiography, in patients with severe AS and preserved LV systolic function.

Methods
We reviewed records of patients with severe AS and preserved LV ejection fraction (≥55%), who underwent TAVR in our institution. We studied pre-procedure, within 1 month post-TAVR and 1 year post-TAVR transthoracic echocardiograms and assessed diastolic function parameters based on the 2016 ASE/EACVI guidelines. Patients who had a paced rhythm, atrial fibrillation or atrial flutter were excluded from the study. Statistical differences were determined by paired t-test using SPSS software.

Results
We identified a total of 173 patients who met inclusion criteria. There was an immediate improvement in diastolic function from baseline to post-TAVR (mean grade, 1.44 vs 1.17; P= 0.019). There was significant improvement in the left atrial volume index (mean mL/m², 38.8 vs 36.8; P= 0.02) and possibly max TR velocity (mean cm/sec, 271 vs 262; P= 0.08). E/A, e’ and E/e’ did not change significantly. At 1 year post-TAVR, there was a significant decline in LV mass index (mean g/m², 112.9 vs 99.5; P= 0.004), LV end-systolic diameter (mean mm, 29.5 vs 27.7; P= 0.01) and a marginal non-significant reduction in LV end-diastolic diameter (mean mm, 44.3 vs 43; P= 0.06). The degree of mitral and aortic regurgitation improved at 1 year (mean grade of regurgitation, 0.89 vs 0.65; P= 0.001, and 0.68 vs 0.54; P= 0.04, respectively).

Conclusions
There is an immediate improvement in diastolic dysfunction in patients with severe AS and preserved LV systolic function undergoing TAVR. There is evidence of regression in several LV volumetric parameters suggestive of conceivable reverse LV remodeling. More studies are needed to validate these findings and investigate the impact on morbidity and mortality.