Reciprocated Tachycardias in Cardiac Laminopathy: a Clinical Case Report

Background Cardiac laminopathies, associated with mutations in the LMNA gene, are a rare inherited disorder characterized by a broad range of clinical manifestations. There is currently no data on the association between supraventricular reentrant tachycardias and LMNA-related cardiomyopathy. Case summary A 26-year-old male presented with either wide QRS tachycardia with a left bundle branch block (LBBB) pattern or narrow QRS tachycardia, as well as a history of palpitations since age 15. Echocardiography showed no overt structural heart disease. Electrophysiological studies (EPS) confirmed the diagnosis of orthodromic atrioventricular reentrant tachycardia (AVRT) mediated by a concealed left posterolateral accessory pathway (AP), with transient LBBB and dual AV-node physiology, characterized by single echo beats. A short-run, asymptomatic episode of atrial fibrillation was induced. Cardiac magnetic resonance (CMR) imaging demonstrated myocardial hyperemia, subepicardial late gadolinium enhancement (LGE), and a small pericardial effusion, initially interpreted as myocarditis according to the modified Lake Louise criteria. A family history of pacemaker implantation and cardiac death at age 65 of the patient’s grandfather, a history of reentrant arrhythmia recurrence following ablation, and further CMR deteriorations led to genetic counseling. Genetic testing identified a heterozygous pathogenic variant in the LMNA gene (NM_170707.3.456_457insTCTC, NP_733821.1.Glu154GlnfsX2), classified as likely pathogenic and associated with laminopathy. Conclusion This case raises the question of whether the combination of reentrant arrhythmias is coincidental or an early indicator of LMNA-related cardiomyopathy.