Fatores preditores de terapia apropriada em portadores de cardioversor desfibrilador implantável

Abstract

The implantable cardioverter-defibrillator (ICD) is indicated for interrupting potentially fatal ventricular arrhythmias, such as sustained ventricular tachycardia or ventricular fibrillation, restoring the normal heart rhythm. Therapy for reversion to the heart's normal rhythm is called appropriate therapy or shock and refers to a shock delivered by an ICD in response to a potentially fatal ventricular arrhythmia and is a crucial intervention to prevent sudden cardiac death in high-risk patients. Identifying patients most likely to receive therapy is a challenge and can assist in the patient's clinical treatment. Objectives: The main objective is to describe the predictors of therapy included in a cohort of ICD patients. The secondary objective is to describe the implications of inappropriate therapy. Methodology: This is a retrospective, single-center cohort study, followed from March 2006 to December 2019, collecting clinical variables, complementary exams and during device evaluation. Results: 230 patients were analyzed with a mean age of 63.6 years, predominantly male with 183 (79.6%) and predominant etiology being ischemic cardiomyopathy, with 130 (56.5%). ICD implantation for primary SCD prophylaxis was observed in 185 (80%) with a predominance of double-chamber ICDs. The average follow-up time was 3.2 years. The evaluated therapy was observed in 18 (7%) patients and inappropriate therapy in 3 (6%), and 71% of these patients were in the AF group. LVEF less than 35% (p=0.040) and NYHA FC III (p=0.044) achieved statistical significance for the primary group, but there was no significant result after multivariate analysis. Conclusion: Although the high functional class and LVEF present predictive data, there is a need for a greater number of patients to confirm the evaluated data.