Long-term changes in primary prevention indication for ICD in patients with HFrEF

Introduction

According to the current guidelines of the European Society of Cardiology on heart failure (HF), implantable cardioverter-defibrillator (ICD) is recommended as a primary prevention in symptomatic heart failure patients (NYHA class II–III) with a left ventricular ejection fraction (LVEF) ≤ 35% after optimal medical therapy (OMT). However, we have very limited data on the long-term evolution of ICD indication.

Methods and patients

In our previous study, which was conducted 10 years ago, the primary prevention indication for ICD was assessed in 693 consecutive patients with heart failure with reduced ejection fraction (HFrEF) before and after OMT. Before OMT, 253 patients (36.5%) met the criteria for ICD implantation. After OMT, due to symptomatic improvement (NYHA class I) and/or recovery of LVEF above 35%, ICD indication persisted in only 92 patients (13.3%). Of the patients with ICD indication prior to OMT, 4 patients died during OMT and 5 were lost during follow-up. This present analysis included the remaining 244 patients (male: 77%; mean age: 58.8±12.0 years; ischaemic etiology: 44.3%, LVEF: 35.50±9.76%; NYHA: 1.69±0.66). The aim of the study was to evaluate changes in the primary prevention indication for ICD over a 10-year follow-up period.

Results

During the 10-year follow-up, 125 patients died (10-year mortality rate 51%). Among the deceased patients, 54 (43.2%) had ICD indication after OMT. At the end of long-term follow-up, ICD indication persisted in 32 of these 54 patients (59.3%). Among 71 patients without ICD indication after OMT, 15 patients (21.1%) fulfilled ICD indication criteria by the end of follow-up.

Among the 119 patients who survived the 10-year follow-up, 37 (31.1%) had ICD indication after OMT, while 82 did not. At the end of long-term follow-up, ICD indication persisted in 14 of 37 patients (37.8%). Among patients without ICD indication after OMT, 16 of 82 patients (19.5%) fulfilled ICD indication criteria at the end of follow-up.

Conclusion

Our results highlight the importance of continuous reassessment of the primary prevention indication for ICD indication during a long-term follow-up of patients with HFrEF. Notably, 20% of patients without ICD indication at the end of OMT fulfilled the ICD indication criteria after a long-term (10-year) follow-up period.