Research in Exercise Echocardiography

Dr. Barbara Cifra with
Dr. Luc Mertens, Dr. Andreea Dragulescu, Dr. Brian McCrindle, Dr. Mark Friedberg

Exercise Stress Echocardiography is a novel technique used in pediatric cardiology. Children cycle on a specially designed bike and images of their heart can be obtained during exercise.

For children who want to be active and participate in different sports activities, understanding how the heart muscle responds to exercise is a very important question.

Modern medicine has given us the possibility to save many children born with congenital heart disease, but it is our responsibility now to make sure that they will have a good quality of life and that they live up to their maximal capability. With the information we will be able to collect on cardiac function during exercise we will not only be able to predict early signs of cardiac dysfunction but we will also be able to counsel families on physical activity.

Being able to safely be active (by playing sports and/or playing with siblings and peers) will improve positively the way these kids look at their life, it will ideally lead to improved self-esteem and increase their physical and mental well-being.

Research in Blood Flow Pattern

Dr. Luc Mertens with
Dr. Wadi Mawad, Dr. Barbara Cifra, Dr. Andreea Dragulescu, Dr. Mark Friedberg, Dr. Deane Yim
In collaboration with
Dr. Siri An Nyrnes, Dr. Lasse Lovstakken, University of Trondheim, Norway

During the last 5 years our team has been working with the Engineering group at the University of Trondheim in Norway to develop an innovative echocardiographic technique to visualize how the blood flows in the heart of children born with heart disease. This technology will allow us to track the blood flow in the heart and vessels (the big conduits, arteries and veins, connected to the heart) and also will help us to better visualize where and how the blood flows through them.

We are the first group in the world with the access to this novel technology.  We will further develop and test it in children with different heart abnormalities and for different medical purposes.

Because the heart is a pump, detailed visualization of how the blood flows in the heart itself and through the main vessels would give us information on how the blood flow affects the heart function in children with cardiac abnormalities.

By collecting this extremely advanced information we will be able to early diagnose signs of cardiac dysfunction in these children and to improve their clinical management.

Research in Fetal Cardiology

Dr. Lynne Nield
with Dr. Conall MorganMs. Callaghan Jull and Dr. Mark Friedberg, Dr. Ra Han, Cedric Manhliot PhD, Dr. Brian McCrindle, Dr. Luc Mertens, Dr. Mike Seed, Dr. Varsha Thakur

Coarctation of the aorta is a condition where the aorta becomes very narrowed, and the narrowing develops in the part of the aorta right after the blood is sent to the brain and the rest of the body.

This causes the lower part of the body to have less blood flow, and less oxygen. In some cases, a child can die from this. The treatment is to perform either a surgical operation to remove the narrowed area or to do a catheter procedure, where a catheter is put into the aorta, and the area is ballooned open or a stent (mesh tube) is inserted.

When a woman is pregnant, we can diagnose coarctation of the aorta in the fetus. However, this is very challenging due to the small size of the fetus, and because the area is often obscured by a large vessel called the arterial duct. It is very difficult to know whether the baby will need urgent surgery or not, and this has huge implications for the management of the mother and baby. 

Our study will try to answer the question of whether a child should have or not have surgery after birth.

Research in Fetal MRI

Dr. Mike Seed
with Davide Marini and Dr. Steven MillerDr. Edgar Jaeggi, Dr. Kingdom

SickKids has developed an innovative technique for studying blood flow distribution and oxygen content of the blood during fetal life. This allows studying the amount of blood flow going to the different organs in a fetus and calculating the amount of oxygen delivered to individual organs.

Through this unique technology we have discovered that the brains of babies with certain severe heart defects are deprived of oxygen prior to birth. We believe that this is the reason for brain damage and delayed brain growth that are typical of children with severe congenital heart defects. This is likely to be the origin of the delays in reaching early developmental milestones and the subsequent cognitive problems observed in children with congenital heart disease. 

Based on our finding that oxygen delivery is reduced in children with congenital heart disease, it seems logical to hypothesize that increased oxygen delivery to the mothers of children with severe heart defects could improve brain development and positively influence long-term neurologic outcomes.