Rockwood Clinical Frailty Scale as a predictor of adverse outcomes among older adults undergoing aortic valve replacement: a protocol for a systematic review

ntroduction Frailty is associated with adverse outcomes relating to cardiac procedures. It has been proposed that frailty scoring should be included in the preoperative assessment of patients undergoing aortic valve replacement. We aim to examine the Rockwood Clinical Frailty Scale (CFS), as a predictor of adverse outcomes following aortic valve replacement. Methods and analysis Prospective and retrospective cohort studies and randomised controlled trials assessing both the preoperative frailty status (as per the CFS) and incidence of adverse outcomes among older adults undergoing either surgical aortic valve replacement or transcatheter aortic valve replacement will be included. Adverse outcomes will include mortality and periprocedural complications, as well as a composite of 30-day complications. A search will be conducted from 2005 to present using a prespecified search strategy. Studies will be screened for inclusion by two reviewers, with methodological quality assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Relative risk ratios with 95% CIs will be generated for each outcome of interest, comparing frail with non-frail groups. Data will be plotted on forest plots where applicable. The quality of the evidence will be determined using the Grading of Recommendations, Assessment, Development and Evaluation tool.