Non-invasive functional assessment using computed tomography: when will they be ready for clinical use?

Area of Science:

• Cardiovascular Imaging
• Radiology
• Medical Diagnostics

Background:

• Coronary computed tomography (CT) angiography is a key tool for detecting coronary artery disease (CAD).
• Anatomical information alone from CT angiography may not accurately indicate if stenosis causes significant ischemia.
• Concerns exist about over-referral for invasive procedures and unnecessary revascularization based solely on anatomical findings.

Purpose of the Study:

• To explore novel methods for evaluating both anatomical and functional aspects of coronary stenosis using CT.
• To assess the diagnostic accuracy of CT-based functional assessments for identifying hemodynamically significant stenosis.
• To determine if combining anatomical and functional CT data can improve patient outcomes and reduce healthcare costs.

Main Methods:

• Investigated CT assessment of myocardial stress perfusion for improved diagnostic accuracy.
• Explored computational fluid dynamics applied to CT angiography for calculating CT-derived fractional flow reserve (FFRCT).
• Compared CT myocardial perfusion imaging and FFRCT against traditional anatomical assessment.

Main Results:

• CT myocardial stress perfusion imaging is feasible and enhances the diagnostic accuracy of CT angiography.
• CT-derived FFR (FFRCT) demonstrates high diagnostic performance in detecting and excluding ischemia-causing stenosis.
• FFRCT calculation does not require protocol changes, additional medication, or increased radiation exposure.

Conclusions:

• CT myocardial perfusion imaging and CT-derived FFR represent significant advancements in cardiac CT.
• These non-invasive techniques combine anatomical and physiological data to assess stenosis significance.
• Anatomic-functional testing prior to intervention may improve patient outcomes and reduce costs, pending further clinical validation.