Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0151744 (myocardial ischemia)
 31,282 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study presents the initial experience of our department with transesophageal echocardiography. Transesophageal echocardiography (TEE) and transthoracic echocardiography (TTE) were performed simultaneously in 31 clinical patients (16 to 76 years old). 13 pts with aortic (9) and mitral (4) valve disease, 10 pts with ischemic heart disease (including 7 AMI), 3 pts with congestive cardiomyopathy, 2 pts with aortic aneurysm and 3 pts with other heart diseases. The investigations were performed with use of Aloka SSD 650 machine and 7.5 MHz transesophageal convex transducer. The patients were prepared for the examination in the typical way by local anesthesia, administration of sedatives and heart monitoring. The following projections were used: basic short- and long-axis view, four chamber view, and transgastric view. These investigation confirmed the usefulness TEE for evaluation of aortic and mitral valves, especially their morphology, atrial septum and atrial cavities. Contractility and other heart structures were difficult to be evaluated by TEE. It seems to be possible to estimate the proximal sections of the coronary arteries. Only few complications were found: supraventricular (2) and ventricular extrasystoles (8), transient supraventricular tachycardia (3), and bradycardia (3). Late complications were not found.
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PMID:[Transesophageal echocardiography--our preliminary experience]. 208 Jan 9

High pulse repetition frequency (HPRF) Doppler and continuous wave (CW) Doppler methods were used to estimate the pressure gradient across the mitral valve. Twenty-two cases of mitral stenosis and five cases of ischemic heart disease were studied. Both the HPRF and CW Doppler studies were conducted during catheterization in all cases. In the Doppler study, pressure gradient was calculated using the simplified Bernoulli's formula. The HPRF device used was a type SSD-730 produced by Aloka Co. It had a reference frequency of 2 MHz. Its minimum pulse repetition frequency was 4.2 KHz; its maximum, 19.2 KHz. Among the 27 cases, the maximum flow velocity measured by the HPRF method at the level of the mitral valve orifice was compared with that by the CW method. As the velocity increased, the discrepancy of measured values between the two methods increased, but it was within 0.1 m/sec. Therefore, there was a good correlation between the HPRF and CW methods (r = 0.98). The pressure gradient between time delay-corrected pulmonary artery wedge pressure and left ventricular pressure was compared with that obtained by the HPRF method. Contrary to our expectations, the correlation coefficient between the two was not so high, and the pressure gradients calculated by the HPRF method tended to be underestimated. For eight patients in whom the left atrial pressure could be recorded, the pressure gradient between the left atrium and left ventricle was compared with that obtained by the HPRF method. There was underestimation, and a good correlation coefficient was obtained. When using pulmonary artery wedge pressure as a substitute for left atrial pressure, one must realize that the time delay varies in every case and that the pressure pulse itself is not the same. When the pressure gradient between the left atrium and left ventricle is used, a good correlation coefficient can be obtained. Therefore, the flow velocity obtained by the HPRF method will reflect the true pressure gradient across the mitral valve. The HPRF method proved to have a potential equal to that of the CW method for estimating mitral valve flow velocity in mitral stenosis, and it may be used as a helpful diagnostic tool.
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PMID:[Pressure gradient across the mitral valve in mitral stenosis estimated by high pulse repetition frequency Doppler method]. 295 25

The purpose of this study was to observe ventricular wall motion in myocardial ischemia and to image coronary artery flow by transvenous intracardiac two-dimensional echocardiography. Ten mongrel dogs (body weight 24-34 kg) were anesthetized by intravenous sodium pentobarbital (25 mg/kg) and ventilated using a Harvard respirator after tracheotomy. Real-time Doppler two-dimensional echocardiography (ALOKA SSD-870) and a transesophageal probe (5 MHz, 24 elements, diameter 6.8 mm, phased array transducer) were used. The probe was introduced into the right atrium via the femoral vein. Myocardial ischemia was induced under fluoroscopic control by the inflation of a balloon catheter in the coronary artery, or by beads embolization of the coronary artery in closed-chest dogs, or by ligation of the coronary artery after a left or right thoracotomy. The wall motion of the right and left ventricles was observed by using the probe positioned in the lower right atrium. Visualization of the coronary artery and the flow velocity were studied with the probe in the mid right atrium. 1) Imaging: The left coronary artery, left main coronary artery and left anterior descending artery were easily observed by the probe positioned in the mid right atrium. The blood flow velocity in the left main coronary artery was consistently recorded. Changes in the blood flow velocity by coronary vasodilators such as dipyridamole, isosorbide dinitrate and nicorandil were clearly detected. 2) Detection of the myocardial ischemia: During the right coronary artery occlusion the right ventricle showed marked dilatation and hypokinesis, and the interventricular septum showed paradoxical movement and was displaced towards the left ventricular cavity.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Evaluation of coronary flow and myocardial ischemia by transvenous and intracardiac two-dimensional echocardiography]. 816 28

Particularities and clinical importance of the structural and functional changes of myocardium were estimated in Chernobyl disaster clean-up workers with atrial fibrillation (AF). We examined 122 men with AF, which was associated with ischemic heart disease and arterial hypertension. Paroxysmal AF was diagnosed in 42 patients, 80 patients had permanent AE Control group comprised 80 men without AF. Echocardiography and Doppler studies were performed using ultrasound scanner Aloka SSD-630 (Japan). Significant structural and functional changes of the heart were revealed already in paroxysmal AF and became more pronounced in permanent AF. Increased left atrial size, its ratio to left ventricular end diastolic diameter, diastolic dysfunction were important echocardiographic predictors of AF. Heart walls thickening was accompanied by disorders of myocardial relaxation, increase in myocardial mass led to ischemia, and together they promoted overload, dysfunction of atrium and development of AF. Obligatory echocardiographic examination of the Chernobyl disaster clean-up workers with ischemic heart disease and arterial hypertension is necessary for predicting AF early, ordering adequate therapy in proper time and improving prognosis.
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PMID:[Structural and functional changes of myocardium in Chernobyl disaster clean-up workers with atrial fibrillation]. 2260 87