Persistent left superior vena cava with absent right superior vena cava

Excerpt

A healthy 39-year-old man had an abnormality detected on electrocardiography (ECG) performed during a medical examination. Twelve-lead ECG revealed high left ventricular potential. On chest radiography, the cardiothoracic ratio was 42%, and the right atrium (RA) was slightly protruding. Transthoracic echocardiography revealed enlargement of the coronary sinus (CS) (Fig. 1a). No other cardiac abnormalities were observed with the standard and right parasternal approaches [1]. Contrast-enhanced computed tomography revealed a persistent left superior vena cava (PLSVC) with absent right superior vena cava (RSVC) (Fig. 1b). The vein of the right upper extremity flowed into the LSVC through the innominate vein. Cardiac catheterization was performed for pressure measurement of the right heart system and shunt scanning. The PLSVC drained into the RA (Fig. 1c), and O₂ step-up was not observed between the distal and proximal CS. The Qp/Qs was 0.96 on cardiac magnetic resonance imaging.

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