Definitive repair of complex congenital cardiac defects in early life has become the recent trend in pediatric cardiac surgery. This early aggressive surgical approach is to avoid the detrimental effects on the heart of chronic cyanosis, hypertrophy and volume overload which are the consequences of unrepaired congenital malformations. Adequate protection of the heart, not only during the period of corrective surgery, but also certain pre-ischemic events remain of paramount importance to the success of these operations. Profound systemic hypothermia followed by total circulatory arrest is widely used for the correction of congenital cardiac defects in the newborn. It involves a period of cold systemic perfusion on cardiopulmonary bypass before circulatory arrest is established. Using an isolated perfused piglet heart model, the first study demonstrated that prolonged cold perfusion of the immature heart could be detrimental in itself. When followed by a period of ischemic arrest, it further potentiated the myocardial injury and induced severe irreversible contracture. Further extension of this study showed that verapamil administered prior to prearrest cold perfusion could indeed minimize the functional and ultrastructural damage of prolonged myocardial cooling. This shed some light to the pathophysiology of prolonged prearrest cooling contracture of the newborn myocardium.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.26146 |
| Date | January 1994 |
| Creators | Shum-Tim, Dominique |
| Contributors | Tchervenkov, C. I. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Division of Surgical Research.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001397872, proquestno: MM94525, Theses scanned by UMI/ProQuest. |
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