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Work toward our objectives will probe and eventually alter the benefit-risk equation central to CTO patient management through three interconnected research programs. Each program describes a series of experiments involving:

  • patient database analyses
  • extensive preclinical studies characterizing vascular pathophysiology
  • technological development of imaging methods and devices
  • evaluation of these tools in animals and humans

Imaging is ubiquitous throughout this research effort.

Goals of imaging include:

  • patient and lesion characterization
  • interventional guidance
  • assessment of the revascularized segment and myocardial function post-procedurally

Clinical outcomes to better identify patients that could benefit most from CTO revascularization

  1. The first part of this study characterizes the subset of patients with known CTO and describes both procedural and longer-term clinical outcomes. This study will prospectively collect data on CTO patients from sites across Canada that are identified at coronary angiography (annual combined volume of more than 45,000 cases).
  2. The second part is a pilot study of 90 CTO patients that examines the value of non-invasive imaging modalities to assess myocardial viability in CTO territories’ long-term coronary stent patency following PCI.

CTO pathophysiology

This study aims to identify specific CTO composition in mature CTOs (ex vivo human specimens) and at various stages of maturation (in vivo animal CTO models). We will also look at how composition relates to lesion compliance and guidewire crossing.

This study relies on detailed histology and various imaging modalities to establish signatures of composition and compliance for differentiating “complex” and “simple” CTO.

Evaluation of novel strategies for improving revascularization of complex CTOs

This study includes improved guidance by substantial development of new in vivo imaging methods including:

  • digital X-ray
  • motion-compensated MRI and CT
  • contrast ultrasound
  • catheter-based ultrasound
  • MRI
  • optical coherence tomography

The imaging methods will be used together with new therapeutic approaches including steerable catheters, enzyme-based therapies and ablative technologies using radiofrequency and mechanical energy.