Abstract
BACKGROUND: Low serum albumin levels indicate frailty and are strong predictors of poor prognosis after mitral transcatheter edge-to-edge repair (M-TEER); however, albumin levels are expected to improve in response to treatment for mitral regurgitation. No reports have elucidated the clinical effects of albumin changes after M-TEER. Thus, we aimed to explore the association between early albumin changes and clinical outcomes after M-TEER and to identify the associated factors. METHODS: Data from 2695 patients enrolled in a Japanese multicenter registry whose serum albumin levels were measured before and 1 month after undergoing M-TEER were retrospectively reviewed. Changes in albumin (Δ-albumin) were calculated and divided into 2 groups, namely improved albumin (Δ-albumin >0) and worsening albumin (Δ-albumin ≤0) groups. The incidence, predictors, and clinical outcomes associated with early albumin changes were investigated. RESULTS: After M-TEER, albumin levels improved in 56.1% of the patients (n=1512). The independent predictors of worsening Δ-albumin comprised old age, acute procedure success not achieved, higher Clinical Frailty Scale, higher hemoglobin, impaired renal function, and preprocedural higher albumin levels (all P<0.05). Improved Δ-albumin was independently associated with reduced all-cause mortality after M-TEER (hazard ratio [HR], 0.62 [95% CI, 0.52-0.75], P<0.001). Additionally, improved Δ-albumin was associated with a lower competing risk of heart failure hospitalization (HR, 0.78 [95% CI, 0.64-0.94], P=0.01). CONCLUSIONS: Early improvement in Δ-albumin may serve as a measure of procedural benefits and a surrogate marker for predicting clinical outcomes after M-TEER.