Abstract 3771: Cardiac Small Vessel Disease by Adenosine-Stress Magnetic Resonance Imaging
Background: Patients with positive testing for myocardial ischemia and without significant coronary artery (CA) stenosis in coronary angiography (CXA) are characterized as “small vessel disease” (SVD). Aim of our study was to identify this patient cohort and detect predictors in stress-perfusion cardiac magnetic resonance (CMR) findings.
Methods: 317 patients with suspected myocardial ischemia and clinical indication for CXA were scanned <72 hours before CXA in a whole-body 1.5T scanner. After three minutes of adenosine (140 μg/kg/min) infusion, myocardial first-pass perfusion sequence in 5 continuous short-axis orientation using Gadolinium-based contrast agent (0.1 mmol/kg) was performed. Images were analyzed by two independent and blinded investigators.
Results: In 78% of patients with relevant perfusion delay perfusion deficit extended to >1/3 of the myocardial wall thickness in ≥2 myocardial segments and persisted for >5 heartbeats and was regarded as “coronary macro-angiopathy”; all of these patients had significant CA stenosis (60% had luminal narrowing >70% and 18% of 50–70%). 22% of patients had perfusion deficits affecting ≤1/3 of wall thickness and persistent for ≤5 heartbeats and were regarded as having SVD; none of these patients had CA stenosis >50%. These patients had more often hypertension (p<0.0001), diabetes (p=0.05) and circumferential perfusion deficits (p<0.0001) compared to other patients.
Conclusion: Stress-perfusion CMR allows non-invasive differentiation between patients with significant CA stenosis and patients with SVD caused by hypertension and/or diabetes based on temporal and spatial extent of perfusion deficits. Patients with SVD have more often diffuse perfusion deficits with shorter persistence than patients with significant CA disease.