Primary prevention of sudden cardiac death (SCD) with an implantable cardioverter-defibrillator (ICD) now is a key element of clinical care in adults with heart failure with reduced ejection fraction (HFrEF). However, risk stratification is needed to ensure that a specific patient with HFpEF will benefit from an ICD because these devices are expensive and may cause harm, including inappropriate shocks. The National Institute for Health and Care Excellence (NICE) introduced new guidelines (TA314) for implantable cardioverter-defibrillators (ICD) in 2014.

In this issue of Heart, Cubbon and colleagues (see page 735) evaluated the prognostic accuracy of the TA314 NICE guidelines in a prospective multicenter cohort of 1026 patients with chronic stable HFrEF (EF ≤45%). The overall risk of SCD or an appropriate ICD shock was 2.1 events per 100 patient-years (95% CI 1.7 to 2.6) with 31.1% of patients meeting TA314 ICD criteria. Compared to those who did not meet criteria, SCD or an appropriate ICD shock was 2.5 times (95% CI 1.6 to 3.9) more likely in patients meeting TA314 ICD criteria. In addition, these patients had an increased risk of death due to progressive heart failure (HR 1.6, 95% CI 1.1 to 2.3) or to non-cardiovascular causes (HR 1.5, 95% CI 1.1 to 2.2). However, risk for diabetic patients who did not meet TA314 ICD criteria was similar to non-diabetics who did meet criteria. Similarly, risk for patients with an ischemic cardiomyopathy who did not meet criteria was similar to those with non-ischemic cardiomyopathy who did meet TA314 ICD criteria (figure 1). These findings were robust on sensitivity analyses. Based on these findings, …