Abstract
BACKGROUND: Patients with angina and no obstructive coronary artery disease (ANOCA) frequently receive empirical antianginal therapy that fails to target underlying pathophysiological mechanisms. Whether stress perfusion cardiac magnetic resonance (CMR)-guided endotyping and stratified medical therapy improves treatment satisfaction and appropriate medication prescribing in this population is uncertain. METHODS: In the Coronary Microvascular Angina CMR Imaging Trial, 250 patients with suspected ANOCA, who had undergone invasive coronary angiography demonstrating no obstructive disease, were enrolled and underwent stress perfusion CMR with quantification of myocardial blood flow. Participants were randomised 1:1 to CMR-guided management (intervention) or angiography-guided management (control). Treatment satisfaction was assessed using the validated Treatment Satisfaction Questionnaire for Medication (TSQM-9) at baseline, 6 months and 12 months. Medication prescriptions were documented at these time points. RESULTS: Stress CMR imaging led to diagnostic reclassification in 53.0% of patients, with microvascular angina diagnosed in 51.0%. At 12 months, global treatment satisfaction was significantly higher in the intervention group compared with controls (adjusted difference, 19.30 units (95% CI 13.89 to 24.71); p<0.001), with consistent improvements across the effectiveness and convenience domains. CMR-guided management was associated with more appropriate prescribing, including higher use of preventive therapies (85.5% vs 67.5%; p=0.001), and more targeted antianginal prescribing, including calcium channel blockers (43.5% vs 27.0%; p=0.008) and long-acting nitrates (56.5% vs 32.5%; p<0.001). CONCLUSIONS: In patients with ANOCA, non-invasive CMR-guided endotyping substantially improves treatment satisfaction and enables more appropriate, mechanism-targeted pharmacotherapy compared with angiography-guided care. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov ID NCT04805814.