Cardiomiopatia hipertrófica apical - Série de casos

Abstract

Background: Apical hypertrophic cardiomyopathy (ApHCM), also known as Yamaguchi syndrome, is a rare phenotypic variant characterized by predominant hypertrophy of the left ventricular distal segments. Despite a generally favorable prognosis, its diagnosis remains a clinical challenge due to its heterogeneous presentation. Objective: To describe the clinical, genetic, and phenotypic characteristics of patients with ApHCM followed at a reference center in Bahia, Brazil. Methods: A descriptive case series of patients followed at the Arrhythmia Outpatient Clinic of the Professor Edgard Santos University Hospital (HUPES/UFBA), who underwent clinical evaluation, electrocardiography, multimodal imaging, and expanded genetic panel testing. Results: Five cases were analyzed (institutional prevalence of 0.19%), with a male predominance and a mean age of 58 ± 10,7. years old. The clinical course was predominantly stable (NYHA I-III), with no reports of syncope or major ventricular arrhythmias. The electrocardiogram (ECG) revealed giant negative T-waves (≥10 mm) in 40% of the sample. Cardiac magnetic resonance (CMR) confirmed the "ace-of-spades" morphology and identified late gadolinium enhancement (LGE/fibrosis) in 80% of the patients, with a modest magnitude (4% to 11%). Molecular analysis revealed variants of uncertain significance (VUS) in the TNNT2 and MYBPC3 genes, with no detection of classic pathogenic mutations. Conclusion: The results reinforce the heterogeneous nature and the generally benign clinical course of ApHCM in the studied population. CMR and genetic evaluation are indispensable tools for precise phenotypic characterization and risk stratification, contributing to the proper management of this frequently underdiagnosed entity in the Brazilian scenario.