Frailty in cardiothoracic surgery: systematic review of the literature.

A preoperative surgical risk analysis is necessary and important for predicting clinical and surgical outcomes in a clinical setting. Various tools for evaluating the patient characteristics in order to forecast perioperative clinical outcomes have previously been described; however, an objective and precise preoperative risk assessment has not yet been established. In the last decade, the concept of frailty, which is a geriatric assessment that identifies disabilities and weaknesses in patients, has been used in order to predict clinical mortality and morbidity following invasive surgical interventions because the prevalence of elderly patients among those undergoing surgical interventions is increasing. Since there is currently no single generally accepted clinical definition of frailty, many clinical modalities are needed to evaluate the patients' geriatric activity of daily living. Quantifying the quality of frailty is an evolving challenge for predicting surgical risks preoperatively. In recent years, with the development of transcatheter aortic valve implantation (TAVI), this newly definitive preoperative surgical risk assessment tool, frailty, has become more important and is attracting interest in cardiothoracic surgical settings. Thus, this review summarized current consideration on the preoperative risk analysis by frailty as well as future perspectives and the potential of an ideal frailty risk assessment in cardiothoracic surgery, including the management of elderly patients and high-risk aortic valve stenosis by TAVI.