Non-invasive prediction of angiographic progression of coronary artery disease by dipyridamole-stress echocardiography.

BACKGROUND: Coronary angiography is the currently accepted standard means for assessing progression of coronary artery disease. A dipyridamole-echocardiography test (DET) might provide an alternative non-invasive functional imaging method for this purpose. OBJECTIVE: To assess whether variations in results of serial DET match variations in angiographic assessments of coronary artery disease. METHODS: From the Pisa Institute of Clinical Physiology stress-echocardiography data bank (1983-1998), we selected 60 patients satisfying the inclusion criteria of coronary angiography and DET having each been performed and interpreted twice independently and within 1 week. The second angiographic and stress-echocardiographic assessment was performed 45+/-31 months after the initial one. Angiographic progressors were defined a priori as patients with any progression of stenosis to occlusion and those with any stenosis > 30% with > 20% progression of stenosis measured by visual and quantitative coronary angiography. Stress-echocardiography progressors were defined as those patients who had previously had a negative test of a test having a positive result and those patients who had positive results of tests both in initial testing and in a second session of testing with the latter having a peak wall-motion-score index > 0.12 (on a scale of 1, normal to 4, dyskinetic in a 16-segment model) larger than the former. RESULTS: Of the 60 patients, 44 were angiographic 'progressors' and 16 were 'non progressors'. Stress-echocardiographic responses were concordant with angiographic identification for 39 of 44 progressors and 15 of 16 non-progressors, with an overall concordance of 90%. CONCLUSIONS: Measurement of dipyridamole-stress-echocardiographic response allows one to separate angiographic progressors and non-progressors efficiently, simply by taking into account the presence, extent and severity of stress-induced abnormalities of wall motion.

New technologies in stress echocardiography.

Stress echo has become the preferred theater where innovative technologies are first tested. The new technologies address, in different ways, various physiological targets: more quantitative assessment of the regional wall thickening (by anatomical M-mode); operator-independent assessment of global and regional systolic function (by anatomic boundary detection and color kinesis); tissue composition and physiologic state (by tissue characterization); transmural stratification of myocardial (subendocardial) function (by tissue Doppler imaging); more quantitative evaluation of contrast-enhanced myocardial perfusion (by harmonic imaging). All new emerging techniques aim to improve display and communication among physicians by translating the description of function into numbers and/or colors. However, cardiologists have to be aware that due the pro-technology bias of modern medicine, we, as physicians, are encouraged to trust, to use (and to buy) technologies far before their clinical incremental value has been shown.

Effect of coronary bypass and cardiac valve surgery on systemic endothelial function.

Seventeen patients scheduled for a cardiac procedure necessitating cardiopulmonary bypass underwent serial perioperative assessment of brachial artery flow-mediated dilation. Patients who underwent coronary bypass surgery had a sustained systemic endothelial dysfunction in the perioperative period, whereas those undergoing cardiac valve surgery experienced transient postoperative systemic endothelial dysfunction.

The impact of second harmonic imaging on stress echocardiography reading.

BACKGROUND: Noncontrast harmonic significantly improves overall image quality in echocardiography. The aim of this study was to assess whether harmonic imaging, without contrast, impacts on interobserver variability and diagnostic accuracy of "beginners" in stress echocardiography. METHODS: Images at rest and peak stress were obtained in digitized format in 15 consecutive patients (10 males, 5 females, mean age 66 +/- 9 years) and analyzed by 5 inexperienced observers (stress echo beginners) who were blinded to the imaging modality (standard versus harmonic imaging). Each observer graded the image quality as 1 = uninterpretable up to 5 = excellent, in a total of 240 segments. RESULTS: The mean image quality per segment was 2.9 for conventional technology and increased up to 3.6 for harmonic imaging (p < 0.001). The interobserver agreement (> or = 4 out of 5 readers) rose from 46 to 60%. The percentage of uninterpretable segments was 7.5% at rest and 8.9% at peak stress of conventional imaging, and decreased to 4.6 and 6.5%, respectively (p < 0.05) by second harmonic technology. The unanimous reading of two additional independent expert observers was arbitrarily assumed to be the "gold standard" to verify the accuracy of reading of the 5 beginners. The 5 beginners showed poor diagnostic accuracy with fundamental imaging (73%), and they did not improve with second harmonic imaging (70%, NS vs fundamental). CONCLUSIONS: Noncontrast second harmonic imaging improves image quality over conventional imaging. The improved quality of the image deflated interobserver variability but did not determine per se an improvement in the diagnostic accuracy of nonexperienced readers.

Safety of ergotamine-ergic pharmacologic stress echocardiography for vasospasm testing in the echo lab: 14 year experience on 478 tests in 464 patients.

BACKGROUND: The safety of ergonovine/ergometrine stress testing for coronary vasospasm when performed outside the cath lab has vigorously been questioned. The aim of this study was to assess the value of ergonovine/ergometrine stress testing performed in the echo lab. METHODS: We retrospectively reviewed the data prospectively collected in the echo lab of the Institute of Clinical Physiology of Pisa (Italy) from January 1, 1985, to October 1, 1998, on 478 tests performed on 464 patients with either ergonovine or ergometrine stress echo testing. By selection, all patients had history of chest pain, consistent with vasospastic angina, negative or ambiguous exercise stress testing, and normal or near normal resting left ventricular function. Ergonovine or ergometrine maleate was injected up to a total cumulative dosage of 0.35 mg, under continuous 12 lead ECG and two-dimensional echo monitoring. RESULTS: There were no death, myocardial infarction, ventricular fibrillation or III degree atrioventricular block. One patient had non-sustained ventricular tachycardia associated with transient ST segment elevation 30 min after the test. Two patients had II degree atrioventricular block, associated with positive echocardiography test and promptly reversed by nitrate administration. Transient regional myocardial dysfunction occurred in 74 patients (15%). Limiting ischemia-independent side effects were present in 13 patients (3%): hypotension in 1, arterial hypertension in 5, nonsustained ventricular tachycardia in 2, and nausea/vomiting in 5. The overall feasibility was 97%. CONCLUSIONS: Pharmacological stress echocardiography with either ergonovine or ergometrine is highly feasible and can be safely performed in the echo lab in properly selected patients in whom coronary vasospasm is suspected. It is often the only way to document coronary vasospasm otherwise missed by conventional noninvasive stress test and even by coronary angiography.