We aimed to assess whether LA-volume-index (LAVI) measured in routine clinical practice of multiple sonographers/cardiologist is associated independently with DMR survival.

A cohort of all 5769 (63±16 years, 47% women) consecutive patients with degenerative mitral valve disease, in whom LAVI was prospectively measured, was enrolled and their long-term survival analyzed.

LAVI (43±24ml/m²) was widely distributed (<40mL/m² in 3154 patients, 40–59ml/m² in 1606 and ≥60ml/m² in 1009). Overall survival throughout follow-up (10-year 66±1%) was strongly associated with LAVI (79±1% vs. 65±2% and 54±2% for LAVI<40, 40–59 and ≥60mL/m², P<0.0001) even adjusting comprehensively, including for DMR severity [adjusted-hazard-ratio 1.05(1.03–1.08) per-10mL/m², P<0.0001]. Mortality under medical management was profoundly affected by LAVI (adjusted-hazard-ratio 1.07[1.04–1.10] per-10ml/mm²; 1.55[1.31–1.84] for LAVI ≥60 vs. <40mL/m², both P<0.0001) incrementally to adjusting variables (P<0.0001) and in all subgroups, particularly Sinus-Rhythm [adjusted-hazard-ratio 1.25(1.21–1.28)] or Atrial-Fibrillation [adjusted-hazard-ratio 1.10(1.06–1.13) per-10mL/m², both P<0.0001]. Thresholds of excess-mortality in spline curve analysis were approximated 40mL/m² in all subgroups. Survival markedly improved after mitral surgery [time-dependent adjusted-hazard-ratio 0.43(0.36–0.53), P<0.0001] but remained modestly linked to LAVI (10-year 85±3% vs. 86±2% and 75±3% for LAVI <40, 40–59 and ≥60ml/m², P<0.0001) (Fig. 1).

The frequent LA enlargement of DMR, measured by LAVI in routine practice, displays, overall and in all subsets, powerful, incremental and independent link to excess-mortality, partially alleviated by mitral surgery. Hence, LAVI measurement should be part of routine DMR evaluation and clinical-decision-making process.