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Ischemic cardiomyopathy is a condition where the heart muscle becomes damaged and enlarged by a lack of blood flow. It’s most often caused by coronary artery disease or a heart attack. 

The lack of blood flow deprives the heart muscle of oxygen, leading to tissue damage and a reduced ability to pump blood. Ischemic cardiomyopathy is linked to progressive shortness of breath and heart failure, the most common type of heart condition in Canada. 

Ischemic cardiomyopathy can be treated with revascularization procedures, such as stents and bypasses, used to restore blood flow to the heart muscle. 

However, when this heart muscle is permanently damaged or scarred, revascularization may not benefit the patient.  

Dr. Jacob Abdaem, a third-year cardiology fellow at the Libin Cardiovascular Institute, says it’s not always straightforward to determine which patients would benefit from revascularization.  

“One would think that if the heart muscle is viable (alive) and you fix the vessel, it will fix the problem, but there hasn’t been evidence that clearly shows that,” says Abdaem. “In fact, it’s often a topic of controversy that comes up during meetings when discussing individual patient treatment.” 

Abdaem, along with a team of researchers at the Libin Cardiovascular Institute, wants to change that and personalize decision-making for individual patients.

Abdaem recently co-first-authored alongside Dr. Dina Labib, PhD, published in JACC: Cardiovascular Imaging, that may help guide clinicians in determining which patients will benefit from early revascularization. 

By combining the value of standardized reporting from cardiac MRI and coronary angiography using tools developed in Alberta, and studying nearly 1,000 patients with ischemic cardiomyopathy, the research team created a new scoring method that predicts mortality benefit from revascularization. 

Regional viability—assessed by MRI—indicates whether heart muscle in a specific area is still alive. This was matched with regional jeopardy, derived from angiography, which shows reductions in blood flow caused by a blocked artery. 

Researchers then looked at the difference between viability and jeopardy across all segments of the heart. 

“We found that patients with three or more segments that were both viable and jeopardized benefitted from early revascularization, while patients with fewer than three such segments didn’t benefit,” says Abdaem, noting the future risk of death was significantly reduced when revascularization was performed in this group of patients. 

The study revealed that a personalized approach that bridges the value of different cardiac imaging modalities identifies individual patients who truly benefit from revascularization and, ultimately, can help save lives. 

“What sets our study apart is that we took a precision medicine approach that looked at the precise anatomy of each individual,” says Abdaem. “It’s an important study because it could provide guidance in clinical decision-making.” 

Labib, who heads the Personalized Diagnostic Program as part of the Libin Precision Medicine Initiative, says developing the new risk score was only possible by combining two large Calgary-based registries and the unique Coronary Artery Reporting and Archiving Tool (CARAT). CARAT is the most widely used coronary artery disease reporting tool in Canada, which was developed in Calgary and is supported by Alberta-based company Cohesic Inc. 

“Bringing those resources together was very powerful,” says Labib. “Combining it with personalized data taken from routine imaging tests will allow this new metric—easily determined through a simple calculation—to guide clinical decisions.” 

More clinical trials assessing this new approach are needed before it can be adopted widely. 

This study was made possible by the Libin Precision Medicine Initiative (LPMI), the Nelson Precision Medicine and Learning Health System (PULSE) Centre for Innovation, and the Cardiovascular Imaging Registry of Calgary (CIROC) and Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) registries. It was co-led by Drs. Robert Miller, MD, and James White, MD.