Cardiac strangulation with chronic ab-extrinseco occlusion of the left-circumflex artery from an epicardial lead: a case report.

Background: Cardiac strangulation (CS) from epicardial pacing leads (EPLs) is a rare and potentially lethal mechanical complication associated with epicardial pacemaker (PM) implantation.

Case summary: We report a case of a 44-year-old-female patient presenting with chest and left shoulder pain in the absence of reported trauma with history of congenital atrioventricular block treated with epicardial PM implantation during the childhood and subsequent transvenous reimplantation over the years. Troponin I resulted within normal values and ECG, transthoracic echocardiography and chest X-ray documented no acute cardiopulmonary findings. After 3 months the patient underwent coronary computed tomography angiography (CCTA) documenting the presence of solid and focally calcified tissue grown along the course of the EPLs, determining multiple focal impressions on the left ventricular epicardial edge and a segmental occlusion of the middle left-circumflex artery (LCX) due to ab-extrinseco compression. After 10 days, the patient was admitted at the emergency department with atypical chest pain and underwent invasive coronary angiography (ICA), which confirmed chronic occlusion of the mid-LCX with complete collateral circulation; a stress echocardiography ruled out myocardial ischaemia and the patient was uneventfully discharged.

Discussion: The diagnosis of CS in patients with epicardial PM leads remains challenging, especially in adults with atypical clinical presentation; thus, any clinical or instrumental clue should prompt further higher-level imaging investigations, such as CCTA or ICA. It is also important to disclose that sometimes CS can be only a collateral finding with no relationship with the patient's symptoms.