Abstract / Summary
Abstract Aims Identifying the infarct-related artery (IRA) before coronary angiography in non–ST-segment elevation myocardial infarction (NSTEMI) is difficult because current approaches have limited sensitivity. We evaluated whether a noninvasive 90-second optically pumped magnetometer magnetocardiography (OPM-MCG) recording can estimate pre-angiography IRA probabilities in these patients and provide information beyond standard-care variables. Methods and Results This prospective two-campus study within one hospital system included a Campus 1 development cohort (n=493) and a geographically separate Campus 2 test cohort (n=118). All patients underwent OPM-MCG before angiography. An XGBoost model using 65 prespecified OPM-MCG features was developed with nested cross-validation, locked, and evaluated once in Campus 2. IRA adjudication followed a core-laboratory hierarchy. Discrimination, calibration, and clinical utility were compared with ECG and TTE. Among 611 patients, 43% had LAD, 23% LCx, and 34% RCA IRA. In Campus 2, overall accuracy was 63.6%, macro-F1 was 60.0%; LAD/LCx/RCA vessel-specific areas under the receiver operating characteristic curve were 0.87/0.79/0.79 and top-1 sensitivity was 76.6%/34.5%/69.0%. Accuracy was 51.7% for matched ECG-only XGBoost and 55.9% for integrated standard care. In an exploratory stacked analysis, adding locked OPM-MCG probabilities to standard care increased accuracy to 67.8% (paired difference 11.9%, 95% CI 4.2–19.5; P=0.008). Conclusions In haemodynamically stable patients with NSTEMI already selected for invasive management, a locked OPM-MCG model provided informative vessel-level probabilities in Campus 2 and complementary signal with standard care. Performance was strongest for LAD and RCA. Prospective multicentre, cross-platform testing is needed before clinical use. Trial registration number: ChiCTR2300070211.