Three-dimensional respiratory-gated coronary MR angiography with reference to X-ray coronary angiography

Area of Science:

• Cardiovascular Imaging
• Magnetic Resonance Imaging
• Interventional Cardiology

Background:

• Coronary artery disease (CAD) diagnosis relies on accurate stenosis detection.
• Conventional X-ray angiography is the gold standard but is invasive.
• Non-invasive imaging modalities are sought for CAD screening.

Purpose of the Study:

• To evaluate the clinical utility of 3D coronary MR angiography (CMRA).
• To assess CMRA's accuracy in detecting significant coronary artery stenosis.
• To compare CMRA against X-ray angiography as the reference standard.

Main Methods:

• Sixty-nine patients with suspected or known CAD underwent both X-ray angiography and CMRA.
• MRI utilized a 1.5-T system with ECG-triggered 3D gradient echo and navigator gating.
• Retrospective navigator echo respiratory gating and fat suppression were employed.

Main Results:

• Analysis included 276 coronary segments; 102 had significant stenoses/occlusions by X-ray.
• CMRA identified 120 stenoses/occlusions, but 16% of segments were excluded due to poor image quality.
• CMRA sensitivity was 75% and specificity 62%; it correctly identified 89% of patients with CAD but missed 6 cases.

Conclusions:

• CMRA with retrospective navigator echo triggering has a high data exclusion rate.
• The false-negative rate limits its use in clinical practice.
• CMRA is not currently recommended as a screening tool for coronary artery disease.