By Celine Zadorsky, Special to Western News
Researchers at Western and Lawson Health Research Institute played a leading role in a new global study that will change the way surgeons repair leaky valves in the heart.
Leaky valve is one of the most common heart conditions, and it often does not present any symptoms. Many patients don’t even realize they have a leaky valve, often presenting to doctors only when they are in the late stage of the disease.
"If the leak in the mitral valve is not repaired, a patient will have problems with fluid retention, shortness of breath and heart failure," said Dr. Michael Chu, one of the lead investigators on the study. "That will then lead to complications requiring hospitalization and, eventually, an increased risk of death."
There are two related valves in the heart that can potentially leak and lead to further complications: the mitral valve and the tricuspid valve. Traditionally, the mitral valve is surgically repaired first, with the belief that it will lead to improvements in the tricuspid valve. However, scientists have discovered that isn’t always the case.
"We were concerned that if we repair the mitral valve only, would the tricuspid valve still leak?" said Chu, who is also the chair of the cardiac surgery division at Schulich School of Medicine & Dentistry.
To answer that question, the research team engaged in a multi-centre, randomized trial run by the Cardiothoracic Surgical Trials Network, a clinical trials network from the National Heart, Lung and Blood Institute in the United States. The study took place in 39 hospitals worldwide with more than 400 cardiac patients.
Chu and his team in London worked with patients through the London Health Sciences Centre. Patients were randomized, half receiving mitral valve repair alone, and half receiving mitral and tricuspid repair surgery at the same time.
"Two years post-surgery, we found that the group that had both mitral and tricuspid repair had significantly less severe residual leak of the tricuspid valve," Chu explained. "These findings suggest that concomitant tricuspid repair is extremely effective, and those patients who present with a tricuspid leak, should have both valves repaired at the same time."
The study findings have been published in the New England Journal of Medicine. Chu, who is joint first author in the paper, believes this research will have an important impact worldwide in how surgical teams repair leaking heart valves and improve patient outcomes.
"This study is really important because it makes it very clear we should be repairing both valves at once to try to reduce future-life complications for patients," he said.
Moving forward, study participants will be followed for five years and further investigations into various aspects of the study will be undertaken, with the ultimate goal of improving long-term outcomes for patients.