[Dobutamine stress echocardiography and perfusion scintigraphy for detection of myocardial ischemia in patients with and without previous myocardial infarct].

UNLABELLED

Dobutamine stress echocardiography has proven to be a method with high diagnostic accuracy in the detection of coronary artery disease. In case of previous myocardial infarction it is of importance to detect additional regions with inducible myocardial ischemia. This study aimed at the detection of inducible ischemia by dobutamine stress echocardiography and stress perfusion scintigraphy in patients without and with previous myocardial infarction. 50 patients without as well as 50 patients with previous transmural myocardial infarction were investigated. In all patients coronary angiography, technetium-99m methoxy-isobutyl-isonitrile (MIBI)-SPECT after bicycle ergometry and dobutamine stress echocardiography (up to 40 mcg/kg/min dobutamine, 1 mg atropine) were performed within 14 days. In patients with previous myocardial infarction dobutamine stress echocardiography and MIBI-SPECT had similar sensitivities (91 vs. 94%, n.s.) and specificities (81 vs. 75%; n.s.) in the detection of significant coronary artery disease. Agreement on the presence or absence of inducible ischemia was 84% (Kappa = 0.60). In patients with previous transmural myocardial infarction sensitivity of stress echocardiography and perfusion scintigraphy in the detection of significant coronary artery disease is lower with 63% and 77%, respectively. In this patient group transient perfusion defects were found more frequently than inducible wall motion abnormalities, 76% and 60%, respectively. There was a lower agreement (76%; Kappa = 0.49) in the detection of abnormal or normal results between dobutamine echocardiography and stress perfusion scintigraphy for this group of patients.

CONCLUSION

This study demonstrates high agreement of dobutamine stress echocardiography and stress perfusion scintigraphy in the evaluation of inducible ischemia in patients without previous transmural myocardial infarction and equal diagnostic accuracy in the detection of coronary artery disease. In patients with previous myocardial infarction there is a lower agreement in the interpretation of patients as having ischemia due to negative dobutamine echo results in patients having positive perfusion scintigraphies.