The hepatic vein-azygos vein connection is a rare Fontan modification used in patients with single ventricle physiology and interrupted inferior vena cava, following an initial Kawashima procedure. We report an unusual case of severe, late-onset hypoxemia due to recanalization of a hepatic vein-atrial communication after this operation. A girl with heterotaxy, mesocardia, unbalanced atrioventricular septal defect, and interrupted inferior vena cava underwent Kawashima surgery at 1 year of age, followed by modified Fontan completion at 4 years, in which hepatic veins were connected to the azygos vein. Nine years later, she presented with profound cyanosis (SpO2 35% to 40%) and polycythemia. Imaging demonstrated recanalization of hepatic vein-atrial communication resulting in significant right to left shunt and diffuse pulmonary arterio-venous malformations. Transcatheter closure of the communication using a 12-mm muscular ventricular septal defect occluder improved oxygen saturation to 65% with symptomatic relief. The hepatic vein-azygos vein connection represents an uncommon Fontan modification designed to ensure uniform distribution of hepatic venous flow to both the lungs. Late recanalization of a hepatic vein-atrial communication following this procedure has not been previously reported. In our case, transcatheter occlusion of the communication successfully redirected the hepatic venous flow to the pulmonary circuit. We describe a previously unreported complication of a rare Fontan modification. Transcatheter closure of a recanalized hepatic vein-atrial communication can effectively restore Fontan physiology and improve systemic oxygenation.

We report the case of an 82-year-old woman with a known history of hiatal hernia who presented with intermittent chest discomfort and exertional dyspnea. Electrocardiography revealed sinus rhythm with axis deviation and a prominent R wave in lead aVR, initially raising concern for limb lead reversal, conduction abnormality, or myocardial ischemia. Chest radiography demonstrated a retrocardiac air-fluid level, and computed tomography (CT) confirmed a large type III hiatal hernia displacing the heart centrally, with the apex directed upward and leftward. No congenital structural cardiac abnormalities were identified. The patient was managed conservatively. This case highlights how a large hiatal hernia can alter cardiac orientation and produce atypical electrocardiographic findings. It underscores the importance of correlating ECG abnormalities with imaging studies to avoid misdiagnosis and unnecessary interventions.

A 37-year-old man presenting with chronic cough was incidentally found to have mesocardia on chest imaging, with a midline heart and associated upper thoracic scoliosis. Further tests revealed eosinophilic asthma, treated successfully. This rare, isolated mesocardia case highlights the importance of recognising abnormal cardiac positioning on routine radiographs.

Coffin-Lowry syndrome (CLS) is a rare X-linked disorder marked by intellectual disability, craniofacial and skeletal anomalies, and progressive spinal deformities like scoliosis and hyperlordosis. Corrective posterior spinal fusion (PSF) surgery is often required. Mesocardia, a congenital anomaly where the heart is positioned centrally in the thorax, may affect perioperative hemodynamics, particularly in the prone surgical position. This report presents a case illustrating the perioperative challenges of PSF in a patient with both CLS and mesocardia. A 17-year-old male with CLS, mesocardia, and severe scoliosis underwent PSF (T2-S2). During prone positioning, the patient experienced a gradual hemodynamic collapse, characterized by a decrease in oxygen saturation and a marked drop in both pulse rate and blood pressure. Repositioning to the supine position led to immediate recovery. Imaging ruled out pulmonary or vascular obstruction, pneumothorax, and embolism. The event was attributed to mechanical cardiac compression related to syndromic soft tissue laxity, thoracic deformity, mesocardia, and posterior soft-tissue release. Surgery was completed using a modified lateral oblique prone position, maintaining hemodynamic stability. This case illustrates the importance of anticipating cardiopulmonary compromise due to anatomical and positional factors and that personalized surgical planning and modified positioning can be crucial in complex spinal deformity surgery in syndromic patients with thoracic abnormalities.

While meso/dextrocardia, a cardiac axis abnormality, is associated with various complications and a poor prognosis, few studies have been reported. We aimed to identify and review patients at our hospital who had been diagnosed with fetal meso/dextrocardia. The medical records of 29 patients diagnosed with fetal meso/dextrocardia between April 1, 2014 and March 31, 2024 were reviewed. We identified eight cases of mesocardia and 21 cases of dextrocardia (17 dextropositions and four dextroversions). Right lung hypoplasia (including 3q trisomy, esophageal bronchopleural fistula, and left pulmonary artery sling) was identified in three cases. Five cases of persistent left superior vena cava (PLSVC) were identified [isolated PLSVC (n = 2), VACTERL association (n = 1), trisomy 13 (n = 2)]. Dextroposition was linked to congenital pulmonary airway malformation (eight cases), left pulmonary sequestration (one case), congenital diaphragmatic hernia (six cases), right lung hypoplasia (one case), and VACTERL association with right lung aplasia and esophageal atresia (one case). Dextroversion was associated with asplenia syndrome (two cases), single-ventricle (one case), and Temple syndrome with PLSVC and bilateral hypoplastic pulmonary arteries (one case). Among 29 newborns, six (20.7%) died during the early neonatal period and seven (24.1%) required postnatal multidisciplinary treatment, highlighting a poor prognosis in many cases. While some patients, such as those with isolated PLSVC, had favorable outcomes, several cases involved severe complications requiring intensive perinatal management. When fetal meso/dextrocardia is detected, it is critical to evaluate fetal anomalies comprehensively and not limit assessment to the heart and lungs.