Addition of atropine to submaximal exercise stress testing in patients evaluated for suspected ischaemia with SPECT imaging: a randomized, placebo-controlled trial.
OBJECTIVE
To evaluate the effects of the addition of atropine to exercise testing in patients who failed to achieve their target heart rate (HR) during stress myocardial perfusion imaging with single-photon emission computed tomography (SPECT).


METHODS
The study was a prospective, randomized, placebo-controlled design. Patients with suspected or known coronary artery disease who failed to achieve a target HR (≥85% of maximal predicted HR) during exercise SPECT imaging were randomized to receive intravenous atropine (n=100) or placebo (n=101).


RESULTS
The two groups of patients did not differ with respect to demographic or clinical characteristics. A higher proportion of patients in the atropine group achieved the target HR compared to the placebo group (60% versus 3%, p<0.0001). SPECT imaging was abnormal in a higher proportion of patients in the atropine group as compared to the placebo group (57% versus 42%, p<0.05). Stress-induced myocardial ischaemia was present in more patients in the atropine group as compared to placebo (47% versus 29%, p<0.01). In both groups of patients, no major side effects occurred.


CONCLUSIONS
The addition of atropine at the end of exercise testing is more effective than placebo in raising HR to adequate levels, without additional risks of complications. The use of atropine in patients who initially failed to achieve their maximal predicted HR is associated with a higher probability of achieving a diagnostic myocardial perfusion study.
Department of Cardiology and Heart Surgery, San Giuseppe Moscati Hospital, Avellino, Italy.
Fiore
F
Manganelli
Marco
M
Spadafora
Paola
P
Varrella
Giuseppina
G
Peluso
Rosario
R
Sauro
Emilio
E
Di Lorenzo
Giuseppe
G
Rosato
Stefania
S
Daniele
Alberto
A
Cuocolo
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D001285:Atropine / Q000009:adverse effects / Q000494:pharmacology*; D002121:Calcium Channel Blockers / Q000627:therapeutic use; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000503:physiopathology*; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D010919:Placebos; D015899:Tomography, Emission-Computed, Single-Photon; D016896:Treatment Outcome
D000319:Adrenergic beta-Antagonists; D002121:Calcium Channel Blockers; D010919:Placebos; D001285:Atropine