FACTORS INFLUENCING THE DIAGNOSTIC-ACCURACY OF DOBUTAMINE STRESS ECHOCARDIOGRAPHY

Background: While Dobutamine stress echocardiography is a well establi shed tool, the range of the diagnostic accuracy found in the literatur e is rather large. The main reason for this is the fact, that differen t test protocols were used. Aim of this study was to assess the effect s of both addition of atropine as well as consideration of a hyperdyna mic response while interpreting the stress echocardiogram on the diagn ostic accuracy. Methods and results: 120 consecutive patients were exa mined and divided into the following groups: A) achieving their age pr edicted heart rate with dobutamine, B) termination of the test due to ischemia, C1) negative test without reaching the predicted heart rate, and C2) C1 following addition of atropine. All of the echocardiograms were analyzed twice: 1) regarding the lack of a hyperdynamic response to dobutamine as ischemia (Hyper analysis), and 2) ignoring the hyper contractility (Conventional analysis). The accuracy of A and B were 88 % and 90% reap. Group C1 had a very poor accuracy of 60%. This rose si gnificantly (p<0.01) after atropine (C2 = 84%), without leading to an increase of adverse effects. Conventional wallmotion analysis lead to an overall accuracy of 87% (groups A, B, and C2), while Hyper analysis showed an accuracy of 90% (p<0.01). Conclusions: To achieve a high ac curacy Dobutamine stress echocardiography should always be combined wi th atropine to reach a target heart rate. The wallmotion analysis shou ld be based on the assumption that a hyperdynamic response to dobutami ne is normal, while its lack is indicative of ischemia.