The objective of this observational study is to evaluate the diagnostic effectiveness of magnetocardiography (MCG) in patients with stable coronary artery disease (SCAD) and compare it with coronary CTA (CCTA). Additionally, the study aims to determine the most suitable diagnostic index for MCG. The primary question it seeks to address is whether MCG or MCG combined with CCTA can be utilized to guide the clinical application of percutaneous coronary intervention (PCI) for coronary heart disease.