Relation between Modified Body Mass Index and Adverse Outcomes after Aortic Valve Implantation

Abstract

We aimed to investigate the relationship of modified body mass index (mBMI), the product of BMI and serum albumin, with survival after transcatheter (TAVI) and surgical aortic valve implantation (SAVI). Frailty is associated with poor outcomes after TAVI and SAVI for severe aortic stenosis (AS). However, clinical frailty is not routinely measured in clinical practice due to the cumbersome nature of its assessment. Modified BMI is an easily measurable surrogate for clinical frailty that is associated with survival in elderly cohorts with non-valvular heart disease. We utilized individual patient-level data from a pooled database of the Placement of Aortic Transcatheter Valves (PARTNER) trials from the PARNTER1, PARTNER2 and S3 cohorts. We estimated cumulative mortality at 1 year for quartiles of mBMI with the Kaplan-Meier method and compared them with the log-rank test. We performed Cox proportional hazards modeling to assess the association of mBMI strata with 1-year mortality adjusting for baseline clinical characteristics. A total of 6593 patients who underwent TAVI or SAVI (mean age 83±7.3 years, 57% male) were included. mBMI was independently associated with all-cause one-year mortality with the lowest mBMI quartile as most predictive (HR 2.33, 95% CI 1.80-3.02, p < 0.0001). Notably, mBMI performed as well as clinical frailty index to predict 1-year mortality in this cohort. In conclusion, modified BMI predicts 1-year survival after both TAVI and SAVI. Given that it performed similar to the clinical frailty index, it may be used as a clinical tool for assessment of frailty prior to valve implantation.