Coronary Artery Disease-Accuracy of Pharmacological Stress Echocardiography
Coronary Artery Disease-Accuracy of Pharmacological Stress Echocardiography
Background: Recent American Heart Association/American College of Cardiology guidelines state that "dobutamine stress echo has substantially higher sensitivity than vasodilator stress echo for detection of coronary artery stenosis" while the European Society of Cardiology guidelines and the European Association of Echocardiography recommendations conclude that "the two tests have very similar applications". Who is right?
Aim:To evaluate the diagnostic accuracy of dobutamine versus dipyridamole stress echocardiography through an evidence-based approach.
Methods: From PubMed search, we identified all papers with coronary angiographic verification and head-to-head comparison of dobutamine stress echo (40 mcg/kg/min ± atropine) versus dipyridamole stress echo performed with state-of-the art protocols (either 0.84 mg/kg in 10' plus atropine, or 0.84 mg/kg in 6' without atropine). A total of 5 papers have been found. Pooled weight meta-analysis was performed.
Results: The 5 analyzed papers recruited 435 patients, 299 with and 136 without angiographically assessed coronary artery disease (quantitatively assessed stenosis > 50%). Dipyridamole and dobutamine showed similar accuracy (87%, 95% confidence intervals, CI, 83-90, vs. 84%, CI, 80-88, p = 0.48), sensitivity (85%, CI 80-89, vs. 86%, CI 78-91, p = 0.81) and specificity (89%, CI 82-94 vs. 86%, CI 75-89, p = 0.15).
Conclusion: When state-of-the art protocols are considered, dipyridamole and dobutamine stress echo have similar accuracy, specificity and - most importantly - sensitivity for detection of CAD. European recommendations concluding that "dobutamine and vasodilators (at appropriately high doses) are equally potent ischemic stressors for inducing wall motion abnormalities in presence of a critical coronary artery stenosis" are evidence-based.
Pharmacological stress echocardiography is widely used for the diagnosis of coronary artery disease, and the two most employed pharmacological stresses are dipyridamole and dobutamine, first proposed more than 20 years ago. The latest 2006 European Society of Cardiology (ESC) guidelines for stable angina conclude that "the two tests have very similar applications and the choice as to which is employed depends largely on local facilities and expertise". This statement was corroborated by a meta-analysis of the published literature, included in the guidelines, and showing comparable accuracy, sensitivity and specificity of dobutamine and vasodilator stress echocardiography. However, and paradoxically, on the basis of the same existing literature, the American Heart Association/American College of Cardiology (AHA/ACC) guidelines stated that "dobutamine stress echo has higher sensitivity than vasodilator stress echo for detection of coronary artery disease" . The recent 2007 recommendations on stress echocardiography of the American Society of Echocardiography conclude that "although vasodilators may have advantages for assessment of myocardial perfusion, dobutamine is preferred when the test is based on assessment of regional wall motion". Who is right? The question has profound clinical relevance, since tens of millions of cardiac stress testing are performed each year, and the projected rises is of + 4,900% in the next decade or so. In addition, pharmacological stress imaging with simultaneous assessment of perfusion and function is also at the basis of the growing application of stress-CMR imaging. A source of ambiguity is represented by the presence of several different protocols of vasodilator stress echo proposed over the years, in the continuing quest of the ideal accuracy: one protocol is suitable for perfusion imaging, another for viability detection, and still another one for ischemia induction. When true ischemia and regional wall motion abnormalities are the diagnostic end-point, we need high dipyridamole doses (0.84 mg/kg), either with atropine co-administration or with a fast infusion rate. Any sound meta-analysis should only include these state-of-the-art protocols, present in the literature since 15 years, in a head-to head comparison with dobutamine stress echo on consecutive populations studied in the same laboratories and with angiographic verification independent of stress results.
Background: Recent American Heart Association/American College of Cardiology guidelines state that "dobutamine stress echo has substantially higher sensitivity than vasodilator stress echo for detection of coronary artery stenosis" while the European Society of Cardiology guidelines and the European Association of Echocardiography recommendations conclude that "the two tests have very similar applications". Who is right?
Aim:To evaluate the diagnostic accuracy of dobutamine versus dipyridamole stress echocardiography through an evidence-based approach.
Methods: From PubMed search, we identified all papers with coronary angiographic verification and head-to-head comparison of dobutamine stress echo (40 mcg/kg/min ± atropine) versus dipyridamole stress echo performed with state-of-the art protocols (either 0.84 mg/kg in 10' plus atropine, or 0.84 mg/kg in 6' without atropine). A total of 5 papers have been found. Pooled weight meta-analysis was performed.
Results: The 5 analyzed papers recruited 435 patients, 299 with and 136 without angiographically assessed coronary artery disease (quantitatively assessed stenosis > 50%). Dipyridamole and dobutamine showed similar accuracy (87%, 95% confidence intervals, CI, 83-90, vs. 84%, CI, 80-88, p = 0.48), sensitivity (85%, CI 80-89, vs. 86%, CI 78-91, p = 0.81) and specificity (89%, CI 82-94 vs. 86%, CI 75-89, p = 0.15).
Conclusion: When state-of-the art protocols are considered, dipyridamole and dobutamine stress echo have similar accuracy, specificity and - most importantly - sensitivity for detection of CAD. European recommendations concluding that "dobutamine and vasodilators (at appropriately high doses) are equally potent ischemic stressors for inducing wall motion abnormalities in presence of a critical coronary artery stenosis" are evidence-based.
Pharmacological stress echocardiography is widely used for the diagnosis of coronary artery disease, and the two most employed pharmacological stresses are dipyridamole and dobutamine, first proposed more than 20 years ago. The latest 2006 European Society of Cardiology (ESC) guidelines for stable angina conclude that "the two tests have very similar applications and the choice as to which is employed depends largely on local facilities and expertise". This statement was corroborated by a meta-analysis of the published literature, included in the guidelines, and showing comparable accuracy, sensitivity and specificity of dobutamine and vasodilator stress echocardiography. However, and paradoxically, on the basis of the same existing literature, the American Heart Association/American College of Cardiology (AHA/ACC) guidelines stated that "dobutamine stress echo has higher sensitivity than vasodilator stress echo for detection of coronary artery disease" . The recent 2007 recommendations on stress echocardiography of the American Society of Echocardiography conclude that "although vasodilators may have advantages for assessment of myocardial perfusion, dobutamine is preferred when the test is based on assessment of regional wall motion". Who is right? The question has profound clinical relevance, since tens of millions of cardiac stress testing are performed each year, and the projected rises is of + 4,900% in the next decade or so. In addition, pharmacological stress imaging with simultaneous assessment of perfusion and function is also at the basis of the growing application of stress-CMR imaging. A source of ambiguity is represented by the presence of several different protocols of vasodilator stress echo proposed over the years, in the continuing quest of the ideal accuracy: one protocol is suitable for perfusion imaging, another for viability detection, and still another one for ischemia induction. When true ischemia and regional wall motion abnormalities are the diagnostic end-point, we need high dipyridamole doses (0.84 mg/kg), either with atropine co-administration or with a fast infusion rate. Any sound meta-analysis should only include these state-of-the-art protocols, present in the literature since 15 years, in a head-to head comparison with dobutamine stress echo on consecutive populations studied in the same laboratories and with angiographic verification independent of stress results.