2. CASE PRESENTATION
A 42 years old man from Iraq with frequent episodes of syncope since one month ago was admitted to the Tehran heart center hospital. He had a history of tricuspid atresia type 2c without reparative surgery. On his admission, the patient had fatigue. On physical examination, he had nail clubbing and cyanosis with an O2 saturation of 75%. His electrocardiogram revealed a complete heart block with a right bundle branch block (figure 1). Echocardiography showed tricuspid atresia with transposition of the great arteries (TGA type), severe pulmonary hypertension (mean of PAP:85mmHg), and dominant left ventricle with LVEF:35%. Cardiothoracic CT was done to evaluate better the cardiac structure, which revealed a large pulmonary trunk, hypoplastic ascending aorta, aortic arch with large PDA, and interrupted aorta. Detailed findings of the Cardiothoracic CT scan are shown in figures 2 and 3. In abdominal CT, an accidental finding was bilateral perirenal fluid accumulation (figure 4).
The risk of the surgery for the epicardial lead placement was high due to pulmonary hypertension; on the other hand, the transvenous pacing would increase the risk of systemic thromboembolism. We discussed the risk associated with each procedure with the patient and recommended the endocardial route, which he accepted. Thus, endocardial pacemaker implantation was scheduled for the patient. After prep and drape, local anesthesia and light sedation were conducted. The left subclavian vein access was gained, and a dual-chamber rate-modulated (DDDR) permanent pacemaker was implanted using a peel-away introducer. Atrial lead was inserted in the right atrial auricle. Ventricular lead was advanced through the atrial septal defect and mitral valve and was placed in the common ventricle. The patient was on heparin during the procedure, and lifelong warfarin was initiated for the patient 24 hours after the surgery. On follow-up, the patient was well and had no complaints. The pacemaker was in the proper position without clot formation. The post-pacing electrocardiogram is shown in figure 1.