Severe Rheumatic Mitral Stenosis, Worse Left Atrial Mechanics is Closely Associated with Echo Criteria for Intervention

Abstract

Background: Rheumatic mitral valve (MV) stenosis is associated with progressive left atrial (LA) fibrosis and functional impairment, Pulmonary artery systolic pressure (PASP) and right ventricular (RV) dysfunction. The aims of the study were to determine in those patients with severe MV stenosis if LA mechanical function as assessed by speckle tracking echocardiography could identify those with increased PASP, atrial fibrillation (AFib), and RV dysfunction. Subjects and Methods: Patients with severe MV stenosis were identified from the institutional echo database. Echocardiograms were read off line and measurements included atrial and ventricular strain. Patients were divided into tertiles of LA reservoir strain (LASr) values and data compared between the groups. Results: Ninety-seven patients, 67 females, mean age 47.4 ± 11.9 years, had MV mean gradient of 8.3 ± 5.1 mmHg, MV area by pressure half time of 1.3 ± 0.3 cm2 and LASr of 11.18% ± 6.4%. Those patients in the lowest LASr tertile had more AFib (72%, P = 0.0001), PASP >50 mm Hg (39%, P = 0.005), and worst RV impairment. In multivariable logistic regression analysis, LASr, age, and mean MV gradient were the independent predictors of AFib and PASP >50 mm Hg. Cutoffs, determined by receiver operating characteristic curve analysis had high specificity for the composite outcome of Afib and PASP >50 mmHg (85% for LASr <7.7%). Conclusion: In severe MV stenosis LASr, age and mean MV gradient, are independent predictors of Afib and PASP >50 mmHg. LASr <7.7% has high sensitivity and specificity in identifying those who meet ESC guideline 2017 criteria for valve intervention, suggesting its potentially helpful addendum to the surveillance of patients with MV stenosis.