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Objectives: Dobutamine stress echocardiography (DSE) and contrast-enhanced electron beam tomography (EBCT) both have the potential to noninvasively detect coronary artery disease (CAD). We compared the accuracy of both methods to detect significant CAD in a direct comparison. Methods: 79 patients (32 women, 47 men, mean age 62 years) who were admitted for coronary angiography due to suspected CAD were studied. By EBCT coronary calcification (CAC) as well as angiography (CTA) was assessed. Presence of significant CAD was assumed if the calcium score exceeded 400 or the contrast-enhanced images displayed significant lumen reduction. DSE was performed using a standard protocol (5–40 μg/kg/min dobutamine plus 0.25–1.0 mg atropine if necessary). DSE and EBCT were independently evaluated concerning the presence of signficant CAD. Results were compared to invasive, quantitative coronary angiography. Results: 6 patients (8%) in DSE and 2 patients (3%) in EBCT were unevaluable for various reasons and therefore excluded from further analysis. In the remaining 71 patients, 33 patients (46%) showed significant CAD. DSE demonstrated a sensitivity of 70% (23/33) and a specificity of 84% (32/38). EBCT showed a sensitivity of 91% (30/33) and a specificity of 74% (28/38). By combining DSE and EBCT sensitivity increased to 97% with a specificity of 63%. Conclusions: In a blinded comparison, DSE demonstrated lower sensitivity but higher specificity than EBCT for the detection of significant CAD. Sensitivity was improved by combining both modalities. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Myocardial viability within the infarct zone is an important determinant for left ventricular (LV) function recovery after interventional coronary revascularization. Echocardiographic techniques are highly valuable in identifying hibernation, especially in conjunction with dobutamine titration. Low doses may detect the inotropic reserve by significant enhancement of segmental wall motion abnormalities while high doses may surpass the ischemic threshold and wall motion deteriorates (biphasic response). According to the Task Forces on Clinical Application of Echocardiography by the American Heart Association (AHA) in cooperation with the American College of Cardiology (ACC), dobutamine echocardiography (DE) is officially recommended for the purpose of clincial decision making in respect of revascularization therapies (whether during the subacute infarct period or especially in chronic LV dysfunction due to coronary artery disease (CAD)). New methods such as strain rate imaging implemented in DE are on the way to give us quantitative measures of the amount of viability.(J Interven Cardiol 2004;17:349–355) [ABSTRACT FROM AUTHOR]

Abstract: In myocardial contrast echocardiography (MCE), power modulation technique may quantify myocardial perfusion in real-time. However, constant infusion of the contrast agent (CA) complicates handling. This pilot study sought for the clinical feasibility of quantitative MCE by a CA bolus application during Adenosine stress echocardiography to diagnose coronary artery disease (CAD). Twenty-four consecutive patients (pts) with contemporary coronary angiography underwent rest and maximum Adenosine stress. Signal intensity could be calculated in 316/348 left ventricular (LV) segments (91%) (18-segment model). At rest, gamma-variate (alpha) as well as saturation function (beta) was not significantly different in healthy men (n = 268) as well as CAD pts (n = 48) (alpha: 0.34 s-1 versus 0.40 s−1, n.s.; beta: 0.31 s−1 versus 0.35 s−1, n.s.). During Adenosine infusion both values increased in healthy men (alpha: 0.34 ± 0.37 s−1 versus 0.44 ± 0.45 s−1, p < 0.05; beta: 0.31 ± 0.33 s−1 versus 0.40 ± 0.40 s−1, p < 0.01), but not in CAD (alpha: 0.40 ± 0.35 s−1 versus 0.29 ± 0.29 s−1, n.s.; beta: 0.35 ± 0.32 s−1 versus 0.27 ± 0.30 s−1, n.s.). Sensitivity of alpha/beta reserve ≤1 was 65%/67% (specificity 66%/67%) and improved to 88% in both if also wall motion analysis was considered (specificity 59%/65%). A very high negative predictive value of 96%/97% favours the method for excluding CAD. Bolus administration of CA is feasible in quantitative real-time MCE. However, additional consideration of wall motion analysis is required for reasonable sensitivity. Very high negative predictive values favour the potential of the method in excluding the diagnosis. Further need of research work may be encouraged by those findings. (E-mail: nixdorff@ecp-checkup.de) [Copyright &y& Elsevier]