[Prevalence of ECG abnormalities in hypertrophic cardiomyopathy: who seeks will find].

Introduction: The 2023 European Society of Cardiology Cardiomyopathy Guidelines emphasize the crucial role of a multiparametric approach in diagnosing. During the diagnostic workup of hypertrophic cardiomyopathy, besides echocardiography and cardiac magnetic resonance, ECG plays an important role. Based on literature data, only 4–18% of patients with hypertrophic cardiomyopathy have normal ECG, however, ECG deviations are often non-specific. Objective: To evaluate the ECG characteristics in a hypertrophic cardiomyopathy patient cohort followed-up at the Heart Failure Outpatient Clinic of Gottsegen National Cardiovascular Center. Method: We retrospectively analyzed the data and the first ECGs registered of patients with hypertrophic cardiomyopathy, diagnosed by cardiac magnetic resonance and/or genetic testing, followed-up between 01. 11. 2023 and 30. 09. 2024 at our Heart Failure Outpatient Clinic. Results: Data from 72 patients were evaluated, male: 58%, age: 49 (34–62) years, left ventricular ejection fraction: 63 (47–72)%, NYHA functional class: 2 (1–2), ICD/CRT-D: 47%. Based on the left ventricular outflow tract obstruction of ≥30 mmHg, 31% of the patients belonged to hypertrophic obstructive cardiomyopathy subgroup. Based on the ECGs analyzed, atrial fibrillation occurred in 6%. Interatrial conduction disturbances affected 29% of the patients. Atrioventricular and intraventricular conduction disturbances occurred in 50% (AV block: 20% [grade I: 18%, grade II: 2%, grade III: 0%], right bundle branch block: 14%, left bundle branch block: 16%, left anterior hemiblock: 13%, left posterior hemiblock: 3%, non-specific intraventricular conduction disturbance: 8%). The sensitivity of the Cornell, Sokolow–Lyon, and Peguero–Lo Presti “high voltage” criteria were low (23–14–25%). Pathological Q wave occurred in 42% of the patients, QRS fragmentation in 43% and corrected QT interval prolongation in 44%. T wave inversion was present in 94%, significant ST elevation in 21%, ST depression in 48%, while only 3% of patients had negative ECG. The only difference between hypertrophic obstructive cardiomyopathy and non-obstructive hypertrophic cardiomyopathy patients was the fulfillment of the Cornell criterion (45% vs. 15%, p = 0.044). Conclusions: A multimodal approach is essential in the diagnosis of hypertrophic cardiomyopathy. Based on our results, hypertrophic cardiomyopathy is often associated with heterogeneous ECG abnormalities. However, the early recognition of the ECG variations may help in the further diagnostic steps, contributing to the initiation of disease-modifying treatment. Orv Hetil. 2025; 166(25): 970–981.