Lack of correlation between noninvasive stress tests and invasive coronary vasomotor dysfunction in patients with nonobstructive coronary artery disease.
BACKGROUND
Despite a nonobstructive coronary angiogram, many patients may still have an abnormal coronary vasomotor response to provocation and to myocardial demand during stress. The ability of noninvasive stress tests to predict coronary vasomotor dysfunction in patients with nonobstructive coronary artery disease is unknown.


RESULTS
All patients with nonobstructive coronary artery disease who had invasive coronary vasomotor assessment and a noninvasive stress test (exercise ECG, stress echocardiography, or stress nuclear imaging) within 6 months of the cardiac catheterization with provocation at our institution were identified (n=376). Coronary vasomotor dysfunction was defined as a percentage increase in coronary blood flow of <or=50% to intracoronary acetylcholine (endothelium-dependent dysfunction) and/or a coronary flow reserve ratio of <or=2.5 to intracoronary adenosine (endothelium-independent dysfunction). We determined the sensitivity and specificity of various noninvasive stress tests to predict coronary vasomotor dysfunction in these patients. On invasive testing, 233 patients (63%) had coronary vasomotor dysfunction, of which 187 patients (51%) had endothelium-dependent dysfunction, 109 patients (29%) had endothelium-independent dysfunction, and 63 patients (17%) had both. On noninvasive stress testing, 157 (42%) had a positive imaging study and 56 (15%) a positive ECG stress test. The noninvasive stress tests had limited diagnostic accuracy for predicting coronary vasomotor dysfunction (41% sensitivity [95% CI, 34 to 47] and 57% specificity [95% CI, 49 to 66]), endothelium-dependent dysfunction (41% sensitivity [95% CI, 34 to 49] and 58% specificity [95% CI, 50 to 65]), or endothelium-independent dysfunction (46% sensitivity [95% CI, 37 to 56] and 61% specificity [95% CI, 54 to 67]). The exercise ECG test was more specific but less sensitive than the imaging tests.


CONCLUSIONS
This study suggests that a negative noninvasive stress test does not rule out coronary vasomotor dysfunction in symptomatic patients with nonobstructive coronary artery disease. This underscores the need for invasive assessment or novel more sensitive noninvasive imaging for these patients.
Cassar
Andrew
A
Department of Internal Medicine, Mayo College of Medicine, Rochester, MN 55905, USA.
Chareonthaitawee
Panithaya
P
Rihal
Charanjit S
CS
Prasad
Abhiram
A
Lennon
Ryan J
RJ
Lerman
Lilach O
LO
Lerman
Amir
A
D000109:Acetylcholine; D000241:Adenosine; D000293:Adolescent; D000318:Adrenergic beta-Agonists; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000503:physiopathology; D003326:Coronary Circulation; D003331:Coronary Vessels / Q000503:physiopathology*; D004176:Dipyridamole; D004280:Dobutamine; D015150:Echocardiography, Doppler; D025401:Echocardiography, Stress; D004562:Electrocardiography; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon; D014665:Vasodilator Agents; D014666:Vasomotor System / Q000503:physiopathology*; D055815:Young Adult
D000318:Adrenergic beta-Agonists; D014665:Vasodilator Agents; D004280:Dobutamine; D004176:Dipyridamole; D000241:Adenosine; D000109:Acetylcholine