Congenital anomalies of the heart may generate difficulties for cardiac invasive procedures. Dextrocardia is a rare congenital heart disease in which the apex of the heart is located on the right side of the chest. Patients with transposition of great arteries (TGA) abnormalities are at risk for complete cardiac block and usually require a permanent cardiac pacemaker in long-term follow-up. The persistent left superior vena cava (PLSCV) is a rare venous anomaly, often associated with abnormalities of the cardiac transduction system. It is usually seen by chance during permanent pacemaker implantation. Even if electrodes are not impossible to be placed through this abnormal venous structure, it can be challenging. In this study, we present a permanent pacemaker implantation to a 31-year-old female patient with a combination of dextrocardia, PLSVC, and TGA due to complete heart block.

Congenital anomalies of the heart can make transvenous procedures such as right heart catheterization or pacemaker implantation difficult. During embryological development, PLSVC occurs as a result of obliteration of the proximal part of the right anterior and right cardinal veins [1]. The left anterior cardinal vein creates a vena cava superior that opens to the right atrium through the left coronary sinus or directly to the left atrium. The persistent left superior vena cava (PLSCV) is rare but the most common systemic venous anomaly, which is 0.5% in general population and 3-10% in congenital heart defects [2]. Another anomaly is congenital dextrocardia, which is a rare congenital heart defect in which the heart is predominantly localized on the right side of the thorax. The reported dextrocardia frequency is 1 in 10,000 live births [3]. It is responsible for 0.5% of cases of adult congenital heart disease [4]. Transposition of great arteries (TGA) is a rare congenital anomaly that represents about 0.5% of congenital heart disease. The oxygenated blood in the pulmonary veins flows from the left atrium to the right ventricle which is compatible with the tricuspid valve and is pumped into the incompatible aorta [5]. In patients with TGA, the AV node and His bundle have an unusual position, resulting in dysfunction of the impulse system. Approximately 2% of patients with TGA develop complete AV block per year [6]. Our patient whom TGA and dextrocardia were combined with a PLSVC had previously developed a full AV block, and repeated attempts of pacemaker implantation with a subclavian approach had failed, and epicardial pacemaker had been inserted. The VVI-R pacemaker was implanted successfully with a subclavian approach to the patient who applied to us due to the end of the battery life.