Abstract 13106: Exercise Tests Cannot Be Used as a Diagnostic Tool for Detection of Coronary Microvessel Dysfunction
Introduction: Current guidelines indicate that patients with angina, a positive exercise test and no obstructive coronary artery disease (CAD) should be suspected of coronary microvessel dysfunction (CMD). The aim of this study was to investigate if exercise tests can identify patients with CMD.
Methods: Women with angina pectoris and no obstructive CAD (<50% stenosis on CAG) were consecutively included in the study (n=763). Coronary flow reserve (CFR) was assessed by TTE during dipyridamole infusion (0.84 mg/kg) and information regarding results from exercise test ≤6 months prior to CAG and risk factors were obtained. Results were categorised as 1) positive based on occurrence of ECG changes or typical angina pectoris symptoms 2) negative or 3) inconclusive.
Results: Exercise test had been performed prior to CAG in 283 of 642 patients (44 %). Patients lacking information were excluded (n=121). Patients with or without exercise test did not differ in CFR, age, smoking status, years of smoking, type-2 diabetes, BMI, hypertension, hypercholesterolemia or CAG result (all p>0.05).There were no significant differences in mean CFR between patients with a positive, inconclusive or negative test and the proportion with CMD (cut off 2.0 and 2.5, respectively) did not differ. Age, smoking status, type-2 diabetes, hypercholesterolemia or CAG results was similar (table). There was a tendency towards less hypertension in the group of patients with a negative test (p=0.051). Furthermore patients with a negative test had been smoking significantly less than patients with an inconclusive or positive test (p=0.04)
Conclusions: No difference in CFR for patients with a positive, inconclusive or negative exercise test was observed. This lack of difference did not seem to be explained by an uneven distribution of risk factors between groups due to selection bias. Exercise tests cannot be used as diagnostic method for CMD, which supports the need for developing novel methods for diagnosing CMD.
Author Disclosures: N. Dose: None. M.M. Michelsen: None. N.D. Mygind: None. A.A. Pena: None. E. Prescott: None.
- © 2014 by American Heart Association, Inc.