B-po05-058 long-term icd related outcomes in patients with inherited arrhythmic syndromes

Patients with inherited arrhythmia and cardiomyopathy syndromes are often recommended an ICD. There is limited information on the long-term outcomes of ICDs in this population. To assess real-world ICD related long-term outcomes in patients with familial arrhythmogenic conditions and their predictors. Registry of patients with an ICD followed at an inherited arrhythmia program between 2008 and 2020. Incidence of therapies and complications were measured as 5-year cumulative incidence proportions and analyzed with the Kaplan-Meier method. We studied 126 patients with a mean age of 38±16 at ICD implant for a mean follow up of 6.4±4.9 years. The diagnosis category was channelopathy in 62% and cardiomyopathy in 38%. A genetic mutation was found in 70%, and SCN5A and PKP2 were the most frequently involved genes. The indication for implant was primary prevention in 60% and secondary prevention in 40%. The 5-year incidence of first appropriate shock was 5% vs. 32.1% (p<0.01) for primary and secondary prevention, respectively. The 5-year incidence of first inappropriate shock was 14% vs 50% (p<0.01) for single vs. multi-lead devices. The 5-year incidence of first lead complication was 16% vs 42.9% (p=0.06) for single vs. multi-lead devices. Patients with an ICD for secondary prevention were significantly more likely to receive an appropriate shock than those with primary prevention indication (HR 2.12 CI 1.1-4.3, p<0.05). Multi-lead devices were associated with higher risk of inappropriate shock (HR 4.41 CI 1.6-12.1, p<0.01), with similar appropriate shock risk compared to single lead devices. Of note, we found that 23% of patients with dual chamber devices did not require atrial sensing or pacing. Patients with familial cardiomyopathy had a greater risk for appropriate shock than those with a channelopathy, despite similar EF (65% vs 60%, p=0.5) and greater proportion of patients with primary prevention indication. The rate of appropriate and inappropriate ICD therapy and lead failure in patients with inherited arrhythmia is high, particularly in cardiomyopathies with multi-lead devices. Risk/benefit ratio should be carefully considered when assessing the indication and type of device in this population.