Exercise electrocardiography (ECG) is frequently used as a diagnostic measure in patients with suspected coronary artery disease (CAD). However, it has low sensitivity for the detection of CAD. Magnetocardiography (MCG) has been proposed as an alternative tool to accurately diagnose CAD.
To date, a direct comparison of MCG to ECG has not been performed. This study sought to compare them for predicting the presence of significantly obstructive CAD.
The patients with chest pain or other symptoms suggestive of CAD were enrolled in the analysis. All the patients underwent a clinical evaluation, exercise ECG, a MCG exercise test, and coronary angiography (CA). CAD was defined as stenosis ≥70% stenosis in at least one major coronary artery on quantitative analysis of CA.
We prospectively enrolled 202 consecutive patients who suggested CAD. The prevalence of CAD on CA was 39.1%. Sensitivity and accuracy for CAD diagnosis was higher for MCG compared with exercise ECG (sensitivities 68.4% and 40.5%, p <0.001, specificities 95.1% and 91.1%, p = 0.267, and accuracies 84.7% and 71.3%, p <0.001, respectively). There was no incremental diagnostic value of combined MCG and ECG to detect coronary artery disease (p = 0.357).
For the patients with intermediate to high risk of CAD, MCG exercise test provides better diagnostic accuracy for the detection of relevant obstruction of the epicardial coronaries when directly compared to exercise ECG.