Coronary vasospasm as a source of false positive results during dobutamine echocardiography.
BACKGROUND
Several studies have demonstrated a consistently high sensitivity of dobutamine echocardiography whereas test specificity in these series has been variable. The aim of this study was to evaluate whether coronary vasospasm--elicited by alpha1 adrenoreceptor stimulation--may be a significant source of false positive responses during dobutamine stress.


METHODS
From the data bank of four institutions we selected 113 patients (75 males, 38 females, mean age 55 +/- 12 years) with dobutamine echocardiography performed (up to 40 micrograms/kg/min and atropine 1 mg if needed) before a coronary angiography showing normal or near normal (visually assessed stenosis severity < 50%) coronary arteries. The following variables--which were previously reported influencing dobutamine echo specificity--entered the multivariate statistical analysis: age, sex, heart rate at baseline and at peak stress, baseline echo, hypertension, site of asynergy, and spasm at coronary angiography.


RESULTS
Twenty-five patients had a positive dobutamine test. The positivity occurred in the left coronary territory in 15 and in the right coronary territory in 10 cases. All the 6 patients with spontaneous spasm during angiography had a false positive stress test result. By multivariate analysis only coronary artery spasm during angiography (p = 0.0015) and history of hypertension (p = 0.0031) were significant predictors of false positive results of dobutamine stress echocardiography.


CONCLUSIONS
Coronary artery spasm may be an important source of false positive results during dobutamine stress echocardiography.
Varga
A
A
Second Department of Medicine, Albert Szent-Györgyi University Medical School, Szeged, Hungary. vargaa@in2nd.szote.u-szeged.hu
Cortigiani
L
L
Rossi
P C
PC
Cseh
E
E
De Nes
M
M
Trivieri
M G
MG
Csanády
M
M
Picano
E
E
D003327:Coronary Disease / Q000000981:diagnostic imaging; D003329:Coronary Vasospasm / Q000000981:diagnostic imaging*; D003937:Diagnosis, Differential; D004280:Dobutamine; D004452:Echocardiography / Q000379:methods; D005189:False Positive Reactions; D006801:Humans; D009203:Myocardial Infarction / Q000000981:diagnostic imaging; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging*
D004280:Dobutamine