Background and purpose: Dobutamine, an adrenergic agonist, has been combined with echocardiography and scintigraphy with MIBI-SPECT to detect coronary artery disease. Our purpose has been to compare echocardiography and MIBI-SPECT scintigraphy during dobutamine infusion for diagnosing coronary artery disease.
Methods: Both tests and coronary angiography have been performed on 72 consecutive patients with chest pain and no previous history of coronary artery disease. Dobutamine had administered up to 40 micrograms/kg/min. Atropine was given when necessary. MIBI was injected at peak stress. Echocardiographic continuous monitoring and SPECT images were carried out. Positivity was defined as: 1) echocardiographic: wall motion abnormalities of new onset, and 2) scintigraphic: dobutamine-induced perfusion abnormalities.
Results: Coronary artery disease was demonstrated in 49 patients. Echocardiography was positive in 37 of them (sensitivity of 75%) and MIBI-SPECT in 43 (sensitivity of 88%; p = NS). Specificity was higher with echocardiography (22/23, 96%) than with scintigraphy (16/23, 69%, p = 0.02). Accuracy was 82% for both tests. More patients with multivessel disease were detected by scintigraphy (61% versus 35%; p = 0.09). Agreement between tests was as follows: 1) results: 77% (kappa = 0.53); 2) segments: 86% (kappa = 0.65), and 3) artery diseased: 90% (kappa = 0.84).
Conclusions: Echocardiography and MIBI-SPECT in combination with doubtamine are useful techniques to detect coronary artery disease. Diagnostic accuracy is similar with both tests.