Abstract 10364: Noninvasive Detection of Microvascular Coronary Dysfunction Using Cardiac Magnetic Resonance Imaging: The NHLBI-Sponsored Women's Ischemia Syndrome Evaluation (WISE) Study
Background: Coronary reactivity testing (CRT) remains the reference standard to evaluate coronary blood flow (CBF) in subjects with suspected microvascular coronary dysfunction (MCD). CRT is time-consuming and poses risk related to invasive coronary angiography. We evaluated CBF reserve (Δ) using adenosine (ADO), acetylcholine (ACH), cold pressor testing (CPT), and nitroglycerin (NTG) during CRT and tested associations with cardiac magnetic resonance imaging (CMRI) perfusion in patients with suspected MCD.
Methods: 41 women underwent both CRT and 1.5T CMRI with core lab readings. Intracoronary (IC) ADO and NTG was by hand-bolus, IC ACH was infused over 3 mins and CPT was performed using ice pack to forehead for 3 mins, all followed by Doppler flow and cine recordings. CBF reserve was calculated based on mean flow velocity and vessel cross sectional area. Quantitative coronary angiography was performed at standardized left coronary sites and also 5 mm distal to Doppler wire, and combined to estimate mean vessel diameter response. Myocardial perfusion reserve index (MPRI) by CAAS MRV 3.3 software (Pie Medical Imaging B.V., Netherlands) was assessed for 6 midventricular segments (global), and stratified by subendocardial and subepicardial areas. Statistical analysis using Pearson correlation ΔCBF was performed.
Results: While all stressors were moderately related in the predicted direction with global, subendocardial and subepicardial MPRI, CPT and NTG were significantly related (Table).
Conclusion: Our results suggest that CMRI MPRI may provide a non-invasive means for detection of ΔCBF in subjects with no obstructive CAD and suspected MCD. Because CPT is relatively easier and may be safer than ACH infusion, further work exploring the utility of CPT for non-invasive detection of MCD is warranted.
- © 2011 by American Heart Association, Inc.