Chronic total occlusions
The Canadian Institutes of Health Research (CIHR) team in occlusive vascular disease at Sunnybrook Research Institute, led by Dr. Bradley Strauss and the director of the Schulich heart research program Dr. Graham Wright, studies chronic total occlusions (CTOs). These are common arterial occlusions that are more than six weeks old. Our primary focus is to develop a comprehensive strategy for assessment, treatment planning, intervention and evaluation of success for coronary CTOs. We are also focused on peripheral arterial disease CTOs, which are more open to initial evaluation of new methods owing to larger vessel calibre, lack of motion and greater accessibility.
Our long-term goal is to achieve better management of occlusive vascular disease by integrating advanced imaging methods with new minimally invasive percutaneous (done through the skin) therapies, guided by a detailed understanding of underlying pathophysiology and health outcomes. Current management is limited by inadequately validated patient selection and technical issues, particularly a widespread belief that CTOs often indicate a clinically stable condition, combined with reluctance to intervene because of the difficulty in crossing the lesion with a guidewire.
This long-term goal can be broken down into three objectives:
- identify patients with CTOs who are most likely to benefit from improved minimally invasive therapies;
- establish a detailed understanding of CTO pathophysiology, including lesion structure, microvascular physiology and evolution over time to inform more accurate patient characterization and more effective treatment development; and
- develop and evaluate new tools for treatment planning and image-guided percutaneous intervention, which will improve success and reduce risk in the effort to re-establish and maintain vessel patency.