Hamood N Al Kindi1, Mahmoud Shehata2, Ayman M Ibrahim3, Mohamed Roshdy2, Walid Simry2, Yasmine Aguib2, Magdi H Yacoub4. 1. Aswan Heart center , Aswan Governate , EGYPT; Department of Cardiothoracic Surgery, Sultan Qaboos University Hospital, Muscat, Sultanate of Oman. 2. Aswan Heart center , Aswan Governate , EGYPT. 3. Aswan Heart center , Aswan Governate , EGYPT; Department of Zoology , Faculty of Science , Cairo University, Giza, EGYPT. 4. Aswan Heart center , Aswan Governate , EGYPT; Department of Cardiac Surgery, Royal Brompton and Harefield NHS Trust, London, UK. Electronic address: m.yacoub@imperial.ac.uk.
Abstract
BACKGROUND: Cor triatriatum sinister (CTS) or divided Left Atrium is a rare congenital cardiac disease in which the left atrium is divided into two chambers by a fibromusclar diaphragm that will cause blood flow obstruction to the left ventricle. Recent animal studies suggested the role of Hyaluronidase-2(HYAL-2) deficiency as a risk factor for developing CTS. In this study will review the histopathological features of this diaphgram . In addition will review our surgical experience with the management of this disease. METHODS: Ten patients underwent surgical correction of CTS between 2010 to 2018. All the patients had complete clinical and imaging evaluation. Histopathogical evaluation were done on the fibromuscalr diaphgrams with myosin , Troponin , Vimentin , Smooth muscle actin , and HYAL-2 to characterize the structure of CTS diaphgram. RESULTS: All patients underwent excision of CTS diaphgram using cardiopulmonary bypass with no early mortality. Most of the patients were having the classical form of CTS in which the diaphgram seprates the pulmonary and the vestibular chambers with no atrial septal defect. The histological studies demonstrate the presence of fibrous, meshyncemal cells, along with cardiac muscle cells at the site of membrane attachments. HYAL-2 enzyme was expressed in the CTS diaphgram. CONCLUSIONS: Surgical repair of CTS provides satisfactory results with low risk of mortality. Our histological studies reveled the cellular composition of the CTS diaphgram. HYAL-2 deficiency may not explain the pathogenesis of CTS and further studies are needed to evaluate the complex mechanisms involved in the development of this disease.
BACKGROUND: Cor triatriatum sinister (CTS) or divided Left Atrium is a rare congenital cardiac disease in which the left atrium is divided into two chambers by a fibromusclar diaphragm that will cause blood flow obstruction to the left ventricle. Recent animal studies suggested the role of Hyaluronidase-2(HYAL-2) deficiency as a risk factor for developing CTS. In this study will review the histopathological features of this diaphgram . In addition will review our surgical experience with the management of this disease. METHODS: Ten patients underwent surgical correction of CTS between 2010 to 2018. All the patients had complete clinical and imaging evaluation. Histopathogical evaluation were done on the fibromuscalr diaphgrams with myosin , Troponin , Vimentin , Smooth muscle actin , and HYAL-2 to characterize the structure of CTS diaphgram. RESULTS: All patients underwent excision of CTS diaphgram using cardiopulmonary bypass with no early mortality. Most of the patients were having the classical form of CTS in which the diaphgram seprates the pulmonary and the vestibular chambers with no atrial septal defect. The histological studies demonstrate the presence of fibrous, meshyncemal cells, along with cardiac muscle cells at the site of membrane attachments. HYAL-2 enzyme was expressed in the CTS diaphgram. CONCLUSIONS: Surgical repair of CTS provides satisfactory results with low risk of mortality. Our histological studies reveled the cellular composition of the CTS diaphgram. HYAL-2 deficiency may not explain the pathogenesis of CTS and further studies are needed to evaluate the complex mechanisms involved in the development of this disease.