“Understanding Right Ventricular Physiology of Tetrology of Fallot”

Doctor's Name: 
Christopher Caldarone, M.D.
Hospital/Institution: 
The Hospital for Sick Children, Toronto

Tetralogy of Fallot (TOF) is a common congenital heart malformation that involves a ventricular septal defect      (hole in the heart), abnormal thickening of  the muscle on right side of the heart and abnormalities in the major blood vessels carrying blood away from the heart. These abnormalities typically cause low oxygen levels in the blood resulting in cyanosis (bluish discoloration to skin). Children typically undergo corrective surgery as an infant to avoid the consequences of the low oxygen levels and altered blood flow patterns.

Surgical correction has a low mortality associated with it. However, children typically require subsequent interventions to prevent against right heart failure. In the immediate post- operative period, some children experience a complicated course that involves depressed heart function that requires intravenous medications and results in a longer, more complicated stay in the intensive care unit.  Why some children experience this remains unknown and how best to predict and treat it are areas of current research.

Our study will look at how the heart muscle of children with TOF functions. We will look at how potential abnormalities in properties governing heart muscle contraction contribute to the post- operative course in the intensive care unit and how drugs commonly used in the intensive care unit affect heart muscle contraction. In addition, we will look at potential mechanisms underlying the depressed heart function.  We will focus on how the heart responds to the consequences of decreased oxygen supply, as this is a major factor for children with cyanotic heart disease undergoing cardiac surgery.

With our research, we hope to gain an understanding of the abnormalities in heart muscle function found in children with TOF. This will ultimately impact on care of the children in the intensive care unit and improve strategies aimed at minimizing myocardial damage associated with surgery. This can potentially impact on the need for future interventions and subsequent long term outcomes. 

Award Date 1: 
2013
Award Amount 1: 
$71,000