Short-term decrease of left atrial size predicts clinical outcome in patients with severe aortic stenosis undergoing TAVR.

OBJECTIVES: We investigated whether transcatheter aortic valve replacement (TAVR) results in a short-term decrease in left atrium (LA) size and whether such decrease may predict patients' clinical outcome.

BACKGROUND: Increased LA size is a hallmark of severe aortic stenosis (AS) and is associated with adverse patients' cardiovascular outcome. Whether TAVR may lead to a decrease in LA size is not known.

METHODS AND RESULTS: Hundred and four patients with severe symptomatic AS and dilated LA undergoing TAVR were enrolled. LA volume was assessed by echocardiography before and shortly after TAVR (median time: 7 days). Composite rate of death and hospitalization for acutely decompensated heart failure (HF) was recorded and clinical status was assessed through NYHA-class evaluation at 12 months median follow-up. After TAVR, 49 patients (47%) demonstrated a decrease in LA volume. Despite a similar baseline NYHA class, patients with decrease in LA size had significant better improvement in clinical status respect to patients with unvaried LA size (NYHA post: 1.2 ± 0.6 vs. 1.8 ± 1.1, p = .001; NYHA reduction: -1.6 ± 0.9 vs. -0.9 ± 1.0, p = .002, respectively). Moreover, these patients had a significantly reduced rate of death or HF-hospitalization (4 vs. 29%, p = .001) and a significantly longer event-free-survival from Kaplan-Meier curves (p = .003). COX regression analysis showed that, among echocardiographic parameters, decrease in LA size was an independent predictor of clinical outcome (HR: 0.149, CI: 0.034-0.654, p = .012).

CONCLUSIONS: The lack of decrease in LA size shortly after TAVR is associated with significantly higher rates of death and HF-hospitalization, as well as with impaired improvement in clinical status during long-term follow-up.