The Diagnostic and Treatment Characteristics of a Rare Morphological Type of Subaortal Stenosis — Dome-Shaped Membrane

The aim of the investigation was to analyze the features of surgical interventions, correction technique, immediate and long-term results of the treatment of a rare morphological type of subaortal stenosis — dome-shaped membrane taking into consideration differential diagnosis with other congenital anomalies causing left ventricular outflow obstruction.

Materials and Methods. Two medical cases were under study: a 20-year-old male patient and a 4-year-old girl operated in Nizhny Novgorod Specialized Cardiological Clinical Hospital. The operations were performed according to standard practice using transsternal median approach. Both patients underwent normothermic perfusion with aortic occlusion under pharmaco-hypothermic cardioplegia.

Results. Echocardiography was found to be the most informative diagnostic technique of any anatomical variant of subaortal stenosis, since it enables to make a diagnosis and determine a morphological obstruction type on the way “left ventricle-ascending aorta”. When determining the indications for a surgical correction of the studied anomaly, one should carry out a differential diagnosis of a dome-shaped morphological type of subaortal membrane with characteristic deformity of the anterior mitral leaflet as one of the causes of subaortal obstruction. The surgery technique for a dome-shaped membrane consists in circular resection of fibrous mass obstructing the left ventricular outflow.

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Orlov V.Е., Belousov Yu.V. The Diagnostic and Treatment Characteristics of a Rare Morphological Type of Subaortal Stenosis — Dome-Shaped Membrane. Sovremennye tehnologii v medicine 2013; 5(3): 89