Incidence of ventricular tachyarrhythmias and clinical outcomes in primary prophylactic ICD patients in relation to localization of myocardial infarction

FUNDING ACKNOWLEDGEMENTS: Type of funding sources: None. INTRODUCTION: According to current guidelines, primary prophylactic ICD implantation is indicated with a class IA recommendation in patients with severely reduced EF < 35% and ischaemic heart disease. However, it is unclear whether there are differences in patient outcomes related to the localization of myocardial infarction. Aim of the study was to compare the incidence of ventricular tachyarrhythmias and clinical outcomes in primary prophylactic ICD-patients with ischaemic heart disease in relation to the localization of myocardial infarction. METHODS: A total of 448 consecutive ICD patients from a prospective single-centre ICD-registry who underwent primary prophylactic ICD implantation due to ischaemic cardiomyopathy between 1996 and 2021 were analyzed. Patients with previous anterior wall myocardial infarction (AWMI, n = 293) were compared to those with posterior wall myocardial infarction (PWMI, n = 155). Patients with both AWMI and PWMI were excluded. The median follow-up time was 6 years in both groups. RESULTS: Patients with AMWI were younger, more often female, and less often received cardiac synchronization therapy (Table 1). Patients with previous PWMI more often had ICD therapy during follow-up (Figure 1) due to the higher incidence of ventricular tachycardias (Table 1). The all-cause mortality rate was similar between both groups. CONCLUSION: Primary prophylactic ICD patients with previous PWMI have a 10% higher incidence of ventricular tachycardias after 6-year follow-up than ICD patients with previous AMWI. This might be explained by the proximity of the inferior infarction to the mitral isthmus and should be considered when ablating VTs in patients with PWMI. [Figure: see text] [Figure: see text]