Hypoplastic left heart associated with scimitar syndrome

Scimitar syndrome with large atrial septal defect and a rare partial anomalous venous drainage in an adult: a case report

Background

Scimitar syndrome is a very rare congenital cardio-pulmonary disease with anomalous right pulmonary vein draining either partially or completely into the inferior vena cava. It is called Scimitar syndrome due to the classical appearance in the chest X-ray, which resembles the curved blade of Turkish sword 'Scimitar'. It commonly associates with atrial septal defect (ASD), hypoplasia of the right lung, dextroposition of the heart, and pulmonary hypertension (PHT).

Case summary

A 67-year-old lady, diagnosed with atrial fibrillation and moderate PHT 3 years ago, presented with worsening bilateral ankle oedema and New York Heart Association class III shortness of breath. Chest X-ray showed the Scimitar appearance. The trans-thoracic and trans-oesophageal echocardiograms revealed a 46 mm ASD and a partial anomalous pulmonary venous drainage (PAPVD) of the right upper pulmonary vein (RUPV) into the right atrium at the junction of the atria. Three-dimensional reconstruction of the computed tomographic pulmonary angiogram confirmed Scimitar syndrome of the right lower pulmonary vein (RLPV). We managed her conservatively on her wish. After 13 months, she succumbed due to a massive stroke.

Discussion

We describe a very rare case of an elderly lady who has Scimitar syndrome with an ASD and evidence of PAPVD of the RUPV; thus, we intend to provide an antecedent for further cases, for prompt and accurate diagnosis and timely interventions in order to prevent life-threatening complications.

Fetal Diagnosis of Scimitar Syndrome in the Presence of Complex Congenital Heart Disease

Fetal diagnosis of scimitar syndrome requires a high index of suspicion. We present two fetal cases of complex congenital heart disease associated with scimitar syndrome, one of them is diagnosed with scimitar syndrome in utero. We emphasize prenatal echocardiographic findings that may assist with arriving at the correct prenatal diagnosis. We also discuss potential challenges in suspecting the presence of scimitar syndrome in utero. The postnatal echocardiographic findings and course are described for both patients. We reviewed the available literature on prenatal diagnosis of scimitar syndrome in the presence of complex congenital heart disease. We describe a new association of VACTERL, imperforate anus, scimitar syndrome, and double-outlet right ventricle all on the same patient, as well as the first prenatal diagnosis of scimitar syndrome associated with hypoplastic left heart syndrome with restrictive atrial septum. Advanced imaging modalities such as a fetal lung Magnetic Resonance Imaging is suggested as a confirmatory test when scimitar syndrome is suspected in utero in the presence of complex congenital heart disease.

Surgical management of the scimitar syndrome

BACKGROUND AND AIM

We sought to address the varied anatomical details, the diagnostic challenges, associated cardiopulmonary anomalies, the techniques, and outcomes of management, including re-interventions of scimitar syndrome.

METHODS

A total of 92 published investigations of scimitar syndrome were reviewed. Diagnostic information was provided by clinical presentations, radiographic findings, transthoracic and transesophageal echocardiography, computed-tomographic angiography, magnetic resonance imaging, angiocardiography, and ventilation/perfusion scans. These investigations served to elucidate the origin, course, and termination of the scimitar vein, the intracardiac anatomy, the presence of associated defects, and the patterns of any accompanying pulmonary lesions prior to surgical intervention.

RESULTS

Of the patients described, up to four-fifths presented during infancy, with cardiac failure, increased pulmonary flow, and pulmonary hypertension. Associated cardiac and extracardiac defects, particularly hypoplasia of the right lung, are present in up to three-quarters of cases. Overall operative mortality has been cited between 4.8% and 5.9%. Mortality was highest in patients with preoperative pulmonary hypertension, and those undergoing surgery in infancy. Despite timely surgical intervention, post-repair obstruction of the scimitar vein, intra-atrial baffle obstruction, or stenosis of the inferior caval vein were reported in up to two-thirds of cases. The venous obstruction could not be related to any particular surgical technique. On long term follow-up, one sixth of patients reported persistent dyspnoea and recurrent respiratory infections.

CONCLUSIONS

Any infants presenting with heart failure, right-sided heart, and hypoplastic right lung should be evaluated to exclude the syndrome. An increased appreciation of variables will contribute to improved surgical management.

Hypoplastic left heart syndrome in PAGOD syndrome

Chromosomal abnormalities as well as non-cardiac anomalies have been identified as independent risk factors for surgical morbidity and mortality in Fontan palliation. The combination of malformations consisting of pulmonary hypoplasia, agonadism (sex reversal), omphalocele, and diaphragmatic defect is compatible with pulmonary artery and lung hypoplasia, agonadism, omphalocele, and diaphragmatic defect (PAGOD). Most cases have been associated with cardiac disease, particularly hypoplastic left heart syndrome (HLHS) that is potentially destined for Fontan palliation. Reported herein is the case of a Japanese female infant diagnosed with PAGOD syndrome along with HLHS (mitral atresia and aortic atresia), in whom intractable respiratory failure manifested as bilateral eventration of the diaphragm and presumed right lung hypoplasia. These characteristic pulmonary lesions associated with the syndrome precluded use of the Fontan pathway.