JACC Cardiovascular Imaging · Jan 30, 2026
Integrated Atrial and Ventricular Strain Assessment in Patients With Severe Degenerative Mitral Regurgitation Undergoing Surgery
By Oh JK, Kwak S, Park CS et al.
BACKGROUND: Current guidelines for degenerative mitral regurgitation (MR) emphasize left ventricular (LV) dysfunction. However, subclinical alterations in left atrial (LA) or LV strain may manifest earlier in severe MR. OBJECTIVES: This study sought to determine whether combined LA and LV strain measurements improve long-term mortality prediction in severe degenerative MR, especially in asymptomatic individuals. METHODS: This retrospective derivation cohort included 1,314 patients (mean age: 55 ± 13 years; 35% women) who underwent valve repair or replacement for severe MR. Preoperative peak atrial longitudinal strain (PALS) and LV-global longitudinal strain (GLS) were measured. Patients were categorized into 4 groups by using spline-derived thresholds (PALS: <21.4%; LV-GLS: >-20.5%). The primary outcome was all-cause mortality (median follow-up, 8.4 years). External validation included 605 independent patients. RESULTS: Impaired PALS (adjusted HR [aHR]: 2.11; P < 0.001) and impaired LV-GLS (aHR: 1.66; P = 0.008) were independently associated with high mortality. The group with both impaired PALS and LV-GLS demonstrated the worst outcome (aHR: 2.50; P < 0.001). In asymptomatic patients (n = 900), the combined use of both strain parameters outperformed traditional LV dysfunction criteria (LV ejection fraction ≤60% or LV end-systolic dimension ≥40 mm), thereby significantly improving net reclassification (net reclassification index = 0.436; P < 0.001) and discrimination (integrated discrimination improvement = 0.024; P = 0.003). Subgroup analyses demonstrated that the prognostic contribution of each strain parameter varied by the functional status of the other chamber. External validation confirmed these associations. CONCLUSIONS: Concomitant impairment of both PALS and LV-GLS identified patients at the highest mortality risk. These findings support an integrated atrial-ventricular strain assessment to improve prognostic stratification, particularly in asymptomatic patients with severe degenerative MR who are undergoing MV surgery.