THE FRAIL-D STUDY: IMPLICATIONS OF THE FRAILTY PHENOTYPE IN PATIENTS UNDERGOING PRIMARY PREVENTION IMPLANTABLE CARDIOVERTER DEFIBRILLATORS

Abstract

Frailty is a syndrome characterized by decreased physiological reserve and vulnerability to stressors. The frail patient is at increased risk of mortality and morbidity when compared to the non-frail patient. While frailty assessments have been utilized in many cardiovascular conditions, there are no studies applying frailty assessments in patients undergoing a primary prevention implantable cardioverter defibrillator (ICD) with or without cardiac resynchronization therapy (CRT-D). The Purpose of the FRAIL-D study is to (1) determine the prevalence of frailty in patients referred for primary prevention ICD/CRT-D and; (2) to measure the impact of frailty on cardiovascular outcomes. The FRAIL-D study is a prospective cohort study enrolling 77 consecutive patients aged ≥65, referred for ICD or CRT-D for primary prevention of sudden cardiac death (SCD) at a tertiary center between 2015 and 2017. At baseline, patients underwent a frailty assessment using the Fried Frailty Score, with a diagnosis meeting standardized cut offs in ≥3 of 5 domains: slowness, weakness, inactivity, exhaustion, and shrinking. The primary outcome is all cause mortality and secondary outcomes include ER presentations, hospitalizations, device therapies and procedural complications, 2 years following implantation. The mean age of the population was 71 ± 4 years and 75% (n=59) were male. The majority of patients had ischemic cardiomyopathy (84%) with a mean LV ejection fraction of 27 ± 7%. Frailty was diagnosed in 12 patients at baseline, a prevalence of 17%. The frail group had a larger proportion of patients with heart failure symptoms (75% vs 43%, p < 0.045, and were more likely to be on diuretics (100% vs 65%, p <0.0001). The primary outcome of all-cause mortality occurred in 58% (7 of 12) of frail patients and 12% (8 of 65) of non-frail patients (p <0.0003; Figure 1). At 2 year follow up, incidence of ER presentations, 92% vs 54% (p=0.009), heart failure exacerbations, 50% vs 12% (p=0.002), and hospitalizations, 83% vs 25% (p <0.001) were all higher in frail patients. Rates of device complications and device therapies were low and not significantly different between groups. The prevalence of frailty in patients ≥ 65 years referred for primary prevention is 17%. Frailty was associated with significantly higher mortality and morbidity when compared to non-frail patients, suggesting an attenuated benefit in this population.