Introduction: Cardiac resynchronisation theraphy (CRT) is an integral part of heart failure management in eligible patients (symptomatic heart failure, QRS du-ration over 130msec, left ventricle systolic dysfunction with ejection fraction equal to or below 35% ). Success-full left ventricular (LV) lead delivery via the coronary sinus (CS) into a postero-lateral tributary is generally considered to be safe, with a high success rate at first procedural attempt.

Methods: A 62-year-old man, with history of anterior ST-elevation myocardial infarction treated with fibri-nolysis and subsequently LV apical aneurysm forma-tion, presented to our cardiac centre with palpitations and severe heart failure. In february 2018 the patient underwent tricameral internal cardiac defibrillator (ICD) implantation in Turkey. ECG at admission re-vealed atrial flutter with variable conduction and large native QRS complexes (140 msec). Echocardiography showed LV ejection fraction (LVEF) of 26%, apical aneurysm and the presence of two electrocatheters into the right ventricle (RV), one with apical course and the other toward the pulmonary infundibulum. Late-ral chest X-ray confirmed the unusual anterior course of the LV lead. Repositioning of the LV lead has been performed.

Results: Successfull LV lead deployment via the coro-nary sinus can be achieved in more than 99,8% of pa-tients. In our case it is unclear if the presence of the LV lead in the RVOT is the result of a dislodgement or the result of an inadvertent placement, unrecognised at the moment of the implant.

Conclusions: T he present case reflect the importan-ce of carefull examination of the chest X-ray, both in frontal and lateral view, and of the electrocardiogram in patients with implantable cardiac devices in order to promptly recognise lead dislodgement or inadvertent placement in another location.