Early diagnostic role of coronary computed tomography angiography combined with cardiac magnetic resonance in MINOCA
P Stradaioli, M Basile, N Vasumini, M Di Leo, M Casuso Alvarez, M Moretti, L Toni, T Manaresi, A Maida, D Fedele, M Armillotta, F Angeli, L Canton, L Bergamaschi, C PizziAbstract
Background
Coronary computed tomography angiography (CCTA) non-invasively detects coronary lesions potentially causing myocardial infarction, but its early diagnostic role in myocardial infarction with non-obstructive coronary arteries (MINOCA) remains unclear.
Objectives
To assess the value of early CCTA combined with cardiac magnetic resonance (CMR) in a non-invasive approach to MINOCA.
Methods
In this prospective, multicentric study, MINOCA patients underwent invasive coronary angiography (ICA), followed within 7 days by CMR and CCTA. Non-ischaemic aetiologies were excluded. ICA evaluated coronary stenosis, myocardial bridges (MB), epicardial spasms, and non-obstructive spontaneous coronary artery dissections (SCAD). CCTA assessed high-risk plaques (HRP), MB, and non-obstructive SCAD. Patients were grouped as MINOCA-CT+ or MINOCA-CT− based on CCTA findings. Fat attenuation index (FAI) and CT fractional flow reserve (FFR-CT) were assessed per-vessel. The primary endpoint was concordance between CCTA-detected lesions and CMR-identified ischaemic damage within the same territory, compared with ICA. ROC analysis evaluated diagnostic performance.
Results
Among 77 confirmed MINOCA patients, 42 (54.6%) had coronary lesions on CCTA. HRP were found in 35 (45.5%) patients, MB in 7 (9%), and no non-obstructive SCAD was observed. MINOCA-CT+ patients exhibited greater total plaque volume, greater myocardial edema (9.2% vs 4.3% of the left ventricle; P=0.003), and infarct size (6% vs 2.4%; P=0.003). FAI ≥–70 HU or FFR-CT <0.80 correlated with edema and myocardial injury on CMR (all P<0.05). Concordance between CCTA lesions and CMR ischaemic pattern was 49.4% (vs 45.5% with ICA; P=0.084 per-patient, P=0.029 per-vessel). CCTA’s positive predictive value for CMR ischaemia was 91% (per-patient) and 78% (per-vessel); negative predictive value was 49% and 89%, respectively—both exceeding ICA. ROC confirmed CCTA's strong performance (AUC 0.74 per-patient, 0.78 per-vessel) to detect concordant ischaemic damage at CMR.
Conclusions
Combined CCTA and CMR identified ischaemic injury and coronary abnormalities in many MINOCA patients. CCTA demonstrated strong diagnostic value elucidating underlying coronary mechanisms.