Fusion of coronary angiography and stress echocardiography for myocardial viability evaluation

Area of Science:

• Cardiovascular Imaging
• Medical Image Analysis
• Interventional Cardiology

Background:

• Identifying viable myocardial tissue is crucial for patients with reduced left ventricular ejection fraction to guide effective revascularization.
• Current methods like cardiac MRI and SPECT are time-consuming; echocardiography offers direct viability assessment in the cath lab.
• Integrating coronary angiograms with myocardial viability imaging is needed for precise procedural guidance.

Purpose of the Study:

• To develop and evaluate a multimodality image fusion technique for superimposing coronary angiograms and echocardiograms.
• To match areas of occluded coronary vessels with regions of viable myocardium.
• To assess the feasibility of direct identification of involved myocardial regions within the catheterization laboratory.

Main Methods:

• Multimodality image fusion was employed to identify corresponding myocardial regions between coronary angiograms and ultrasound scans.
• Geometrically correct superposition of images was achieved using an electromagnetic tracking system for co-registration.
• The system was validated using a cardiac phantom test device in a simulated cardiac catheterization laboratory environment.

Main Results:

• Automated multimodality fusion successfully superimposed images of occluded coronary arteries and regional myocardial viability.
• In vitro experiments using a cardiac phantom achieved a 2D projection error of 3.8±1.1 mm.
• The system demonstrated the potential for direct identification of myocardial regions affected by occluded vessels.

Conclusions:

• Automated fusion of coronary angiograms and stress echocardiograms enables accurate superimposition of vascular and viability data.
• This integrated approach is promising for single-step angiography and angioplasty, potentially reducing procedure time, costs, and hospital stays.
• Further in vivo validation is required to confirm the clinical utility and efficacy of this novel system.