Abstract 15170: Prognostic Implication of Left Atrial Reservoir Strain in Severe Mitral Stenosis With Low Transmitral Diastolic Pressure Gradient: Result From Long-Term Follow-Up Registry

Abstract

Background: Prognosis of severe mitral stenosis (MS) with low transmitral mean diastolic pressure gradient (MDPG) has not been fully understood with lack of long-term follow-up study. Aims: We investigated the prognostic implication in severe MS with low MDPG. Methods: We included patients with severe rheumatic MS (mitral valve area [MVA] < 1.5 cm 2 ) from the Multicenter mitrAl STEnosis with Rheumatic etiology (MASTER) registry. Patients with severe MS were categorized into high (≥ 5 mmHg) or low (< 5 mmHg) MDPG groups. The primary outcome was a composite of all-cause mortality and stroke. Among 1,248 patients with severe MS, 322 (25.8%) had low and 926 (74.2%) had high MDPG. Results: Their mean age was 59±13 years, 25% were men, and 74% had atrial fibrillation. Patients with low MDPG were older and had a higher prevalence of atrial fibrillation. During a mean follow-up of 6.8±5.9 years, 194 patients (15.5%) experienced composite events. Patients with severe MS and low MDPG had a higher risk of experiencing composite events compared to those with high MDPG (hazard ratio [HR]: 1.56, 95% CI: 1.15-2.12; p=0.004). Subgroup analysis with low MDPG revealed that decreased left atrial reservoir strain (LARs) was independently associated with poorer outcome (HR, 2.58, 95% CI: 1.08-6.20; p=0.034). Conclusion: Severe MS patients with low MDPG are at higher risk of adverse events compared to those with high MDPG. The assessment of LARs can be useful in identifying subgroups of low MDPG severe MS patients with poor prognosis.