Case report
Informed written consent was taken from the patient’s guardian for the publication. A 3 month old infant weighing 2.2 Kg was hospitalized with respiratory distress. On examination, patient was tachypneic, cyanosed and dilated veins were visualized all over the chest and abdomen. A faint ejection systolic murmur was heard at left upper sternal border and per abdomen revealed mild hepatomegaly. Chest X-ray revealed slight cardiomegaly with prominent hilar markings. Electrocardiogram (ECG) was consistent with features of right ventricular hypertrophy (RVH). Mild hepatomegaly was observed on ultrasound abdomen. Trans-thoracic echocardiography (TTE) revealed anomalous pulmonary venous confluence behind left atrium (LA), draining directly into superior vena cava (SVC) from right lateral aspect at junction of SVC with right atrium (RA). There was a discrete narrowing at this confluence. SVC was grossly dilated proximal to the stenotic site with flow velocity of 2.5m/sec across the narrowed segment. RA and right ventricle (RV) were dilated and an ostium secondum atrial septal defect (OS-ASD) was also present. Contrast enhanced computed tomography (CECT) chest, revealed that all 4 pulmonary veins (PV) joined to form a common chamber (CC) behind LA which was draining into SVC at SVC-RA junction with discrete narrowing at the junction. There was bulbous dilatation of SVC proximal to stenotic site (Figure 1).
With provisional diagnosis of obstructed supracardiac total anomalous pulmonary venous connection (TAPVC) and congenital SVC stenosis, patient was taken up for surgery. Per-operatively, proximal SVC as well bilateral innominate veins were hugely dilated. Circumferencial stenosis at lower end of SVC (approximately 1 cm in length), starting at SVC-CC junction and extending distally till its termination into RA was observed (Figure 2). Drainage of the CC was into the lower end of SVC at its right lateral aspect by an opening that was roughly 3-4 mm in size. RA, RV were dilated. Cardiopulmonary bypass (CPB) was established with aortobicaval cannulation, with special emphasis on high SVC cannulation. After cardioplegic arrest, the heart was rotated anticlockwise around its axis and dropped into right plural cavity. Anastomosis of LA with CC was done. SVC was widely incised on its lateral aspect. Circumferential fibrosis was observed within the distal part of SVC emanating from the drainage site of CC into SVC (Figure 3). The connecting vein between CC and SVC was doubly ligated from outside, and SVC was augmented with a rectangular pericardial patch (Figure 4). Patient was weaned off CPB with inotropic support and nitric oxide (NO). Trans-esophageal echocardiography (TEE) intra-operatively, ruled out any significant gradient across SVC-RA junction, and CC-LA anastomosis. Delayed sternal closure was done and patient had an uneventful recovery.