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IN THE CONTEXT OF AGEING: The Doppler echocardiography is a non-invasive technique that permits assessment of the "physiological" ageing of the cardiac and vascular structures, notably including a concentric remodelling of the left ventricle associated with relaxation abnormalities, dilatation of the left atrium, valvular reorganisation and a modification in the large vessels. IN A PATHOLOGICAL CONTEXT: The Doppler echocardiography also detects the various cardiovascular affections related to ageing: valvulopathies, notably calcified aortic stenosis and mitral failure due to mitral anulus calcification or prolapsus of the valve; primary hypertrophic cardiomyopathy or secondary to arterial hypertension or an amyloidosis, and possibly leading to heart failure with spared systolic function, frequent in elderly patients; ischemic cardiopathies that have benefited, as in younger patient, from new echographical stress testing techniques, which safely study the variability in myocardial ischemia. Transoesophageal echography can also be performed in elderly patients, but the indications of this more invasive and less well-tolerated examination must be assessed case by case. It is very useful when an intra-parietal aortic hematoma is suspected or during aortic dissection or infectious endocarditis.

ROUTINE EXPLORATION: Echocardiography during dopamine perfusion has been widely proven as an effective tool for determining myocardial viability. Dobutamine has marketing authorization in France for stress-echocardiography and is widely used in clinical practice outside research protocols. The exploration must however be conducted within an appropriately equipped cardiac intensive care unit. Stress-echocardiography has certain advantages over isotropic techniques, in terms of equipment costs, examination time and exposure to isotopes. POST-INFARCTION: Dobutamine-echocardiography enables detection of viable myocardium within the infarct zone, evaluates the degree of residual ischemia in the infarct zone and provides information on prognosis. It would not however be reasonable to perform stress-echocardiography as a first line exploration after infarction. International guidelines recommend a sub-maximal ECG exercise test prior to coronarography. The contribution of stress-echocardiography after infarction is its ability to give precise information on myocardial viability and residual ischemia in one or more territories to compare with coronary lesions, thus allowing indication for revascularization. CHRONIC ISCHEMIC CARDIOPATHY: Dobutamine-echocardiography can be used to detect hibernating myocardium in patients with chronic ischemic cardiopathy. In this indication, the sensitivity of stress-echocardiography is slightly lower than thallium scintigraphy, but its specificity and positive predictive values are higher. The best predictive value is obtained with bimodal dobutamine-echocardiography: improve-med thickening at low doses and a degradation at high dose is predictive of functional improvement after revascularization in 72% of the cases. In more severe cases with ejection fraction < 35%, improvement in hibernating myocardium after revascularization leads to a significant improvement in left ventricular ejection fraction.

The morphologic features of the gastric mucosa in patients with cirrhosis have been well investigated. The aim of this study was to evaluate its functional disruption by measuring the gastric potential difference. Forty patients were investigated, 12 control subjects and 28 consecutive cirrhotic patients with endoscopically proved congestive gastropathy. Potential difference was measured the morning, on an empty stomach, at least 3 days after endoscopy; the method used a double channel gastric perfused probe placed under fluoroscopy 10 cm above the cardia, and a subcutaneous reference, both connected to a millivoltimeter via gelose agar-KCl bridges. Potential difference was recorded in each case 20 min before (baseline) and after local instillation of lysine acetylsalicylate (500 mg) as a provocative test. Cirrhotic patients had significantly lower basal potential difference than controls (-28.3 +/- 1.5 mV vs -33.8 +/- 1.3mV, p = 0.007). Potential difference was significantly lower in patients with severe gastropathy than in patients with mild gastropathy (-20.5 +/- 2.1 and -28.9 +/- 1.6 mV, respectively, p less than 0.01). After stimulation with acetylsalicylate, the area under curve and the irritability index were greater in patients with gastropathy (81.4 +/- 12.8 vs 41.2 +/- 8.6 mV.min, p = 0.032 and 0.935 +/- 0.19 vs 0.290 +/- 0.07 mV.mV.min, p = 0.022, respectively). These differences were explained by a higher drop in potential difference (delta DPmax/baseline; 28.1 +/- 3 vs 16.1 +/- 3 p. 100, p = 0.006) whereas basal return time remained unchanged (16.2 +/- 2.1 vs 13.7 +/- 2.2 min).(ABSTRACT TRUNCATED AT 250 WORDS)