Objectives: To describe the incidence of atrial fibrillation induced by dobutamine stress echocardiography and characterize patients at risk of developing atrial fibrillation, by constructing a simple validated risk score index.
Design: An observational study using prospectively collected data.
Methods: 3800 consecutive patients in sinus rhythm undergoing dobutamine stress echocardiography were randomly divided to a case (2/3) and test group (1/3). Associations of predetermined demographic, clinical, electrocardiographic and echocardiographic variables were calculated in patients with and without atrial fibrillation induced by dobutamine stress echocardiography in the case group. Logistic regression analysis determined significant independent risk predictors, a scoring index was constructed and validated on the test group.
Results: There was a 2% incidence of dobutamine stress echocardiography-induced atrial fibrillation in the study population. Risk predictors of atrial fibrillation included: a history of atrial fibrillation (2 points), increased left atrial diameter, right bundle branch block, decreased rest heart rate and hypertension (1 point each). The case subgroup low-risk patients (score 0-2) had a 1% risk, moderate-risk patients (score 3) a 2.7% and high-risk patients (score 4-6) a 14.5% risk of developing atrial fibrillation during dobutamine stress echocardiography. The rates in the test subgroup were 1%, 3.8% and 15.3%, respectively.
Conclusion: Atrial fibrillation during dobutamine stress echocardiography is not common, the risk of developing atrial fibrillation during dobutamine stress echocardiography can be predicted by using a simple risk score system comprised of clinical, electrocardiographic and rest echocardiographic variables, which may be of help when planning a dobutamine stress echocardiography test in selected cases.