[Non-invasive assessment of coronary artery bypass grafts -- an update]

Area of Science:

• Cardiovascular Imaging
• Medical Diagnostics
• Interventional Cardiology

Background:

• Coronary artery bypass grafts (CABG) have limited longevity and graft occlusion can lead to recurrent symptoms, necessitating regular follow-up.
• Accurate assessment of CABG patency is vital for patient management and to avoid invasive procedures like coronary angiography.

Purpose of the Study:

• To evaluate the role of non-invasive imaging techniques, specifically computed tomography (CT) and magnetic resonance imaging (MRI), in assessing coronary artery bypass grafts.
• To compare the strengths of CT and MRI in evaluating graft morphology, patency, and function.

Main Methods:

• Review of current literature and clinical practice regarding CT and MRI for coronary bypass graft imaging.
• Focus on multidetector CT (MDCT), particularly 16-slice scanners, for morphological assessment.
• Discussion of MRI's capability for functional assessment, including coronary flow reserve.

Main Results:

• CT, especially MDCT, is a robust technique for assessing graft morphology, anastomoses, native coronary arteries, and detecting stenoses.
• MRI provides valuable functional information, such as coronary flow reserve, and can be integrated into multiparametric protocols.
• Non-invasive imaging is effective for follow-up of asymptomatic patients, with nearly one-third experiencing asymptomatic bypass occlusion five years post-operation.

Conclusions:

• Non-invasive imaging with CT and MRI offers high accuracy for evaluating coronary artery bypass graft patency and function.
• CT is preferred for morphological assessment, while MRI excels in functional evaluation and can guide management decisions, potentially averting coronary angiography.
• These techniques are essential for the long-term surveillance of CABG patients, improving diagnostic accuracy and patient outcomes.