Clinical usefulness of coronary non-contrast Magnetic Resonance Angiography for selected patients with renal dysfunction or past allergic reaction to iodinated contrast medium

Abstract

Abstract Objective: To verify the usefulness of coronary non-contrast Magnetic Resonance Angiography (coronary MRA) for selected patients with disadvantageous physical conditions. Materials and Methods: Between July 2016 and May 2023, 55 cases were examined by coronary MRA for selected patients with decreased renal function, past allergic reaction to iodinated contrast medium (ICM), heavy calcification of the coronary arteries on the plain CT or patient refusal of ICM and suspected coronary artery disease. Those patients did not have comparable examination methods such as CTA or CAG, to calculate sensitivity and specificity. Therefore, clinical follow-up studies were performed in 47 out of 55 cases to verify that there had been no acute coronary syndrome in the intervening period when MRA excluded or could not identify significant stenosis. Excluded cases were poor image (1), lost case (1), preceded CTA (3 cases), repeated examination (1 case), and early death (2). The average follow-up period was 39.8 months (1-83 months). The MRA was taken by a 1.5T MRI machine with 3D whole-heart magnetic resonance angiography and a 32-channel cardiac coil, utilizing a steady-state free precession MR sequence, respiration navigation and cardiac gating Acquired MR data were processed by Fujifilm Synapse Vincent. Results: The follow-up studies showed no occurrence of acute coronary syndrome in any of the patients after coronary MRA. Conclusion: Coronary MRA was useful for the patients with disadvantageous physical conditions such as decreased renal function or past allergic reaction to ICM, although there are some limitations for MRA. Note: CAG stands for coronary angiography.