Clinical Impact of Early Changes in Serum Albumin on Patient Prognosis After Mitral‐Transcatheter Edge‐to‐Edge Repair

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.