Advances in Heart Failure Frailty and the Selection of Patients for Destination Therapy Left Ventricular Assist Device

F railty is the aggregation of subclinical physiological insults across many organ systems resulting in a syndrome of heightened vulnerability in the face of stress. Measures of frailty are highly predictive of adverse outcomes in many medical and surgical populations but have never been formally applied to patient selection for destination therapy left ventricular assist device (LVAD). Patients with severe heart failure being considered for destination therapy LVAD often have advanced age or noncardiac morbidity that renders them ineligible for transplantation. At the same time, these patients should have reasonable life expectancy to adequately realize the benefits of LVAD. As such, destination therapy LVAD-eligible patients are in a precariously narrow state of health often marked by a high degree of frailty. However, distinguishing frailty that will reverse with LVAD therapy (LVAD-responsive frailty) from frailty that will not (LVAD-independent frailty) is challenging. In this review, we summarize existing tools for destination therapy LVAD patient selection, define the syndrome of frailty, propose a conceptual distinction between LVAD-responsive frailty and LVAD-independent frailty, extrapolate the existing frailty literature to destination therapy LVAD-eligible patients, and identify directions for future research, including systematic collection of preoperative gait speed in this patient population. Left ventricular assist devices (LVADs) for destination therapy (DT) are increasingly used in patients with advanced heart failure with reduced left ventricular ejection fraction who are ineligible for heart transplantation. 1,2 The most common reason for heart transplant ineligibility is advanced age, although pulmonary hypertension, renal failure, recent cancer diagnosis, and diabetes mellitus with end-organ damage are also exclusion criteria. 3 Therefore, DT LVAD candidates are older (mean age, 61.7 years for DT compared with 52.7 years for all other ventricular assist devices) and have significantly worse multimorbidity than other ventricular assist device candidates. 3 Advanced heart failure itself leads to considerable morbidity, including exercise impairment, muscle wasting, and cognitive dysfunction. This combination of advanced age, comorbid disease, and heart failure-related morbidity often leads to the syndrome of frailty. Frailty is defined as impairment in multiple, interrelated organ systems causing decreased homeostatic reserve and increased vulnerability to stress. 4,5 Measures of frailty, even after adjustment for age and comorbidity, are highly predic-tive of death, incident disability, and hospitalization in patients with heart disease 6 –13 and those undergoing cardiac surgery. 14 –16 Application of objective measures of frailty to the related area of mechanical circulatory support is a logical extension of this novel prognostic …