2024, Number 1
Cardiovasc Metab Sci 2024; 35 (1)
Complete heart block in an adult patient with isolated congenitally corrected transposition of the great arteries and situs inversus
Alanís-Naranjo, José Martín; Galeana-Abarca, Cielmar; Campos-Garcilazo, Virginia
ABSTRACT
Congenitally corrected transposition of the great arteries (ccTGA) is a rare congenital heart disease. Many patients remain asymptomatic when no cardiac lesions are present (isolated ccTGA). In ccTGA, the atrioventricular conduction system may be abnormal, resulting in progressive dysfunction and, eventually, a Complete Heart Block (CHB). In ccTGA with situs inversus, the conduction pathway resembles a normal tract, but the atrioventricular node is located posteriorly. Compared with situs solitus, spontaneous CHB is uncommon in ccTGA patients with situs inversus. We report the case of a 40-year-old female without previous medical conditions or having a family or personal history of heart disease presented with loss of consciousness. At admission, electrocardiography revealed bradycardia, CHB, and hypertrophy of the right ventricle. Cardiovascular imaging tests detected an isolated ccTGA with situs inversus and levocardia. The Holter monitor revealed intermittent CHB. Exercise testing demonstrated chronotropic incompetence. An epicardial pacemaker was implanted, and the patient was discharged symptom-free. At a two-years follow-up remains asymptomatic. This case illustrates the importance of cardiovascular imaging in defining cardiac anatomy, ruling out other congenital heart defects, and facilitating pacing therapy in complex congenital heart disease. Congenital heart disease patients should be treated by a multidisciplinary team with expertise in permanent pacing.