Atropine first is safer than conventional atropine administration in older people undergoing dobutamine stress echocardiography

Objective: Early injection of atropine during dobutamine stress echocardiography (DSE) has been demonstrated in retrospective analyses to reduce the duration and dose of dobutamine infusion, while preserving a similar diagnostic accuracy with a lower incidence of adverse effects. This study explores the safety of using atropine as a start drug before dobutamine infusion (ADSE protocol) in comparison with the conventional protocol (DASE protocol) in older patients undergoing DSE for ischemia evaluation.Methods: One hundred consecutive older patients were prospectively enrolled. When eligible, they were randomly assigned to undergo either the DASE protocol (group A, 50 patients) or the ADSE protocol (group B, 50 patients) when atropine (1.0 mg) was first administered 3 min before dobutamine infusion followed by 0.5 mg increments (maximum 1.0 mg) thereafter. Patients were monitored for adverse drug effects. Test duration was calculated.Results: The mean age of the whole study cohort was 67.8 ± 4.3 years and 58 (58%) were men. Patients in group A had longer test duration (21.8 ± 1.3 versus 13.7 ± 0.77 min, p < 0.001) and higher mean dobutamine infusion rate (39 ± 8.2 versus 28.2 ± 9.5 μg/kg/min, p < 0.001). The two groups received a similar total dose of atropine. Group A patients showed significantly higher incidence of extrasystoles, nonsustained ventricular tachycardia and severe hypotension ( p < 0.05).Conclusion: In older patients undergoing DSE, using atropine as a start drug, that is, adopting the ADSE protocol, is associated with shorter test duration, lower mean dobutamine infusion rate and consequently fewer adverse effects.