Clin Res Cardiol 100, Suppl 1, April 2011

P1344 - Cost-effectiveness and direct costs of dual-source computed tomography and invasive coronary angiography in patients with an intermediate pretest likelihood for coronary artery disease
 
M. Dorenkamp1, K. Bonaventura2, C. Sohns1, C. Becker3, A. Leber4
 
1Herzzentrum, Abt. Kardiologie und Pneumologie, Universitätsklinikum Göttingen, Göttingen; 2Klinik für Kardiologie, Angiologie und konservative Intensivmedizin, Klinikum Ernst von Bergmann gGmbH, Herz-, Thorax- und Gefäßzentrum, Potsdam; 3Institut für Klinische Radiologie, Klinikum der Universität München, Campus Großhadern, München; 4Klinik für Kardiologie u. Internistische Intensivmedizin, Städt. Klinikum München GmbH, Herzzentrum München-Bogenhausen, München;
 
Background: Contrast enhanced multi-detector computed tomography (MDCT) has emerged as a valuable non-invasive tool to evaluate coronary arteries. Due to technological advancements, MDCT has rapidly evolved from 4-row detector systems to latest generation scanners including 320-row detector row systems and dual-source computed tomography (DSCT) systems. However, direct costs and comparative cost-effectiveness of cardiac DSCT as an alternative to invasive coronary angiography for diagnosing patients with suspected coronary artery disease (CAD) are unknown.
Methods: The study was based on a patient cohort with an intermediate pretest likelihood for CAD and on complementary clinical data. All patients had uninterpretable or equivocal non-invasive stress tests and underwent DSCT the day before invasive coronary angiography. Cost calculations (in EUR) were based on a detailed analysis of direct costs and generally accepted accounting principles were applied. Direct costs were comprised of three categories: diagnostic-specific equipment costs, materials and supplies costs, and personnel costs. Based on Bayes’ theorem, a mathematical model was used to compare cost-effectiveness of both diagnostic approaches. Total costs included direct costs, induced costs, and costs of complications. Effectiveness was defined as the ability of a diagnostic test to accurately identify a patient with CAD. By definition, invasive coronary angiography was the gold standard test with a 100% diagnostic accuracy. A sensitivity analysis was performed in order to evaluate the robustness of our data.
Results: DSCT image quality was graded sufficient for analysis in 98% of patients. Overall sensitivity and specificity of DSCT coronary angiography were 95% and 90%, respectively. False-negative DSCT test results occurred in 1% of patients. Direct costs amounted to 98.60 EUR for DSCT and to 317.75 EUR for invasive coronary angiography. Equipment costs were nearly the same for both diagnostic approaches, however, material and supplies costs of invasive coronary angiography were approximately 10-fold, and personnel costs were nearly double when compared to DSCT coronary angiography. Analysis of model calculations indicated that cost-effectiveness grew hyperbolically with increasing prevalence of CAD. Given the prevalence of CAD of the study cohort (24%), DSCT was found to be more cost-effective than invasive coronary angiography (970 EUR versus 1,354 EUR for one patient diagnosed correctly with CAD). At a disease prevalence of 49%, DSCT and invasive angiography were equally effective with costs of 633 EUR. Sensitivity analysis revealed cost-effectiveness of DSCT coronary angiography in diagnosing CAD up to an average disease prevalence of 40%. Above a threshold value of disease prevalence of 55%, proceeding directly to invasive coronary angiography was more cost-effective than DSCT.
Conclusion: This is the first study to evaluate cost-effectiveness of a latest generation DSCT scanner in diagnosing CAD in a well-defined cohort of patients with an intermediate pretest disease likelihood. With proper patient selection and consideration of disease prevalence, we found DSCT to be cost-effective. However, the range of eligible patients may be smaller than previously reported and the most important step for physicians in selecting the appropriate diagnostic approach (DSCT versus invasive coronary angiography) is based on a clinical estimation of disease likelihood.
 
Clin Res Cardiol 100, Suppl 1, April 2011
Zitierung mit Vortrags- oder Posternummer s.o.
DOI 10.1007/s00392-011-1100-y

http://www.abstractserver.de/dgk2011/ft/abstracts/P1344.htm