SPECIAL SECTIONS
Pharmacologic stress echocardiography: can we forget "state-of-the-art" protocols?
Albert Vargaa
a Institute of Clinical Physiology, Pisa, CNR, Via Paolo Savi, 8, 56123 Pisa, Italy
In a recent issue of the Journal, Fragasso et al. (1) reported on the comparison of different stress imaging modalities for the detection of coronary artery disease in hypertensive patients. Their final conclusion was that stress echocardiography appears to be the most valuable tool for predicting significant coronary artery disease, and that among pharmacologic stressors, dobutamine stress echocardiography should be the first choice. In my opinion, this statement should be read with caution. First of all, the authors applied protocols of stress testing that do not represent the accepted "state-of-the-art" modalities of pharmacologic echocardiography. In case of a negative stress test response, atropine was not used either during dobutamine or dipyridamole echocardiography. Although they mentioned that atropine coadministration improves the diagnostic power of both tests, they explicitly stated that the accuracy of dobutamine stress remains higher. I must disagree with this statement. It is well known from a large-scale, multicenter study, that in a group of patients taken off beta-blockers (such as those studied by Fragasso et al.), atropine coadministration dramatically increases the sensitivity of dipyridamole testing, whereas it only mildly affects the sensitivity of dobutamine echocardiography (2). Atropine coadministration with dobutamine markedly increases the test sensitivity in a group taking beta-blockers (3). Moreover, in a meta-analysis of 12 reports comparing head-to-head dipyridamole and dobutamine echocardiography, there was no significant difference in the diagnostic accuracy of both tests. Dobutamine was more sensitive in patients with one-vessel disease, but this advantage disappeared in patients with multivessel disease. The specificity of dipyridamole was consistently higher, and the accuracy of the two tests was similar (4). The result of the meta-analysis is perfectly in agreement with the data of Fragasso et al., showing that the accuracy of the two tests is similar, with a higher sensitivity of dobutamine in single-vessel disease and a higher specificity of dipyridamole in patients with normal coronary arteries. Interestingly, Astarita et al. (5) have recently studied dipyridamole/atropine echocardiography and perfusion scintigraphy in hypertensive patients with a positive exercise electrocardiography test. Using the same selection criteria of Fragasso et al., they also showed a similar sensitivity and higher specificity of dipyridamole stress echocardiography versus perfusion scintigraphy. In contrast to Fragasso et al., Astarita et al. used a "state-of-the-art" atropine protocol, and they in fact observed that dipyridamole sensitivity was raised to 88%. Stress echocardiography protocols have evolved rapidly in recent years. When the diagnosis is the target, atropine coadministration should be used. When prognostic stratification is the reason for testing, a high dose without atropine, even in hypertensive patients (6), provides excellent stratification (7).
 |
References
|
|---|
1. Fragasso G, Lu C, Dabrowski P, Pagnotta P, Sheiban I, Chierchia SL. Comparison of stress/rest myocardial perfusion tomography, dipyridamole and dobutamine stress echocardiography for the detection of coronary disease in hypertensive patients with chest pain and positive exercise test. J Am Coll Cardiol. 1999;34:441–447[Abstract/Free Full Text]
2. Pingitore A, Picano E, Quarta Colosso M, et al. The atropine factor in pharmacological stress echocardiography. J Am Coll Cardiol. 1996;27:1164–1170[Abstract]
3. Fioretti PM, Poldermans D, Salustri A, et al. Atropine increases the accuracy of dobutamine stress echocardiography in patients taking beta-blockers. Eur Heart J. 1994;15:355–360[Abstract/Free Full Text]
4. Picano E, Bedetti G, Varga A, Cseh E. The comparable diagnostic accuracy of dobutamine-stress and dipyridamole-stress echocardiographies: a meta-analysis. Coron Artery Dis 2000;11:151–9.
5. Astarita C, Nicolai E, Liguori E, Gambardella S, Rumolo S, Maresca FS. Dipyridamole-echocardiography and thallium exercise myocardial scintigraphy in the diagnosis of obstructive coronary or microvascular disease in hypertensive patients with left ventricular hypertrophy and angina. G Ital Cardiol. 1998;28:996–1004[Medline]
6. Cortigiani L, Paolini EA, Nannini E. Dipyridamole stress echocardiography for risk stratification in hypertensive patients with chest pain. Circulation. 1998;98:2855–2859[Abstract/Free Full Text]
7. Echo-Persantine International Cooperative (EPIC) and Echo-Dobutamine International Cooperative (EDIC) study groupsPingitore A, Picano E, Varga A, et al. Prognostic value of pharmacological stress echocardiography in patients with known or suspected coronary artery disease: a prospective, large scale, multicenter, head-to-head comparison between dipyridamole and dobutamine test. J Am Coll Cardiol. 1999;34:1769–1777[Abstract/Free Full Text]
|
Top
References