Successful balloon valvuloplasty of a subpulmonic membrane associated with cor triatriatum dexter: a case report

Subpulmonary membrane: A rare cause of right ventricular outflow tract obstruction

Subpulmonary membrane is a rare cause of right ventricular outflow tract (RVOT) obstruction, and only a few case reports exist with or without associated ventricular septal defect. We report a series of three cases with subpulmonary membrane causing RVOT obstruction. Two of these have been operated (the first case operated after unsuccessful attempt at balloon dilatation), and the third case is on follow-up at present.

Surgical management of divided atrial chambers

BACKGROUND AND AIM

The morphological variations when one, or both, of the atrial chambers is subdivided, are many and varied. We sought to address clinical presentations, potentially misdiagnosed cases, diagnostic modalities, surgical approaches, and outcomes of this "family" of uncommon lesions.

METHODS

A total of 193 published investigations were synthesized. Diagnostic information was provided by clinical presentation, and multimodality imaging studies.

RESULTS

Almost three-quarters of patients with divided atrial chambers present during infancy with severe pulmonary hypertension and cardiac failure. Associated cardiac and extra-cardiac defects are present in between half and nine-tenths of cases. Acquired division of the left atrium has been reported after the Fontan operation, orthotopic cardiac transplantation, and complicated aortic valvar infective endocarditis. Surgery under cardiopulmonary bypass remains the definitive treatment. Balloon dilation may be considered in anatomically compatible variants in the setting of cardiac failure and pregnancy as a bridge todefinitive treatment. Overall, mortality has been cited between nil to 29%. Presentation during infancy, associated congenital anomalies, pulmonary hypertension, and surgery in the previous era, have been the reported causes of death. The operative survivors have long-term favourable outcomes, with near normal cardiac dimensions and low risk of recurrence. While asymptomatic patients with division of the right atrium do not need treatment, surgical resection of the dividing partition under cardiopulmonary bypass is recommended in symptomatic patients with complex anatomy, the spinnaker malformation, or associated cardiac anomalies. Balloon dilation may be considered in uncomplicated patients with less obstructive lesions. Hybrid intervention and endoscopic robotic correction also have been performed.

CONCLUSIONS

Resection of the dividing shelf allows the survivors to regain near normal dimensions with a low risk of recurrence. We submit that an increased appreciation of the anatomic background to division of the atrial chambers will contribute to improved surgical management.