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)

The direct manipulation of coronary blood flow to induce regional myocardial ischemia has been almost entirely limited to experimental animal models. Thus, the detection of ischemia-induced left ventricular dysfunction in human subjects has been generally limited to observations made under conditions of diagnostic loading or during spontaneous clinical events. Percutaneous coronary angioplasty requires repeated interruptions of coronary blood flow for periods as long as 1 minute. The resulting appearance of or increase in ischemia-produced changes in myocardial function were detected by two-dimensional echocardiography in 18 patients undergoing angioplasty of 22 coronary stenoses. Accordingly, left ventricular contraction was studied during 52 episodes of regional coronary blood flow interruption and reperfusion in the process of inflating and deflating the angioplasty balloon. Before angioplasty, left ventricular wall motion was normal in 14 patients. There was mild anteroapical hypokinesia in two patients, anteroapical akinesia in one and mild inferior hypokinesia in one. Balloon inflations repeatedly produced new or increased wall motion abnormalities in the distribution of the instrumented coronary artery in 19 (86.4%) of the 22 procedures, but did not alter wall motion during angioplasty of one left circumflex artery lesion, one highly collateralized left anterior descending artery stenosis and one left anterior descending stenosis that had already caused severe anteroapical dyssynergy. Hypokinesia, usually rapidly progressing to dyskinesia, began 19 +/- 8 seconds (mean +/- SD) after coronary occlusion. Wall motion began to normalize 17 +/- 8 seconds after reperfusion.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Sequence of mechanical, electrocardiographic and clinical effects of repeated coronary artery occlusion in human beings: echocardiographic observations during coronary angioplasty. 315 58

A study of 44 coronary patients and 11 normal subjects (all of them males) demonstrated different patterns of circulatory response to psychoemotional stress in coronary patients, as compared to normal subjects. Hypokinetic circulatory response to psychoemotional stress is indicative of reduced myocardial contractility due to myocardial ischemia induced by a psychogenic stimulus, while hyperkinetic circulatory transformation in response to stress is a more adequate hemodynamic reaction in coronary patients.
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PMID:[Hemodynamic support of the psychoemotional reaction of ischemic heart disease patients]. 408 73

A technique for epicardial mapping of segmental myocardial function at multiple sites over both right and left ventricles was developed using a high-resolution, 7.5-MHz, short-focus, miniaturized, M-mode echocardiographic transducer worn on the fingertip. Myocardial function was determined from the extent and time course of systolic thickening and diastolic thinning at each site mapped. The technique was characterized in an open-chest canine model of myocardial ischemia. Ischemia was induced by transient or permanent coronary occlusion in 17 dogs. Acute occlusions produced reduced segmental thickening within 10-15 seconds and, often, overt systolic thinning of ischemic myocardium. Rhodamine fluorescence perfusion maps were compared with echocardiographic maps in nine dogs. Segmental thickening was reduced in perfused segments adjacent to, but not involved by, ischemia, as well as ischemic segments. Reproducibility appeared satisfactory for quantitative analysis of grouped data on multiple segments, and qualitative analysis in individual segments. Initial human studies performed during coronary bypass surgery in 11 subjects showed echocardiographic abnormalities in the six patients with ventriculographic abnormalities and in four with normal ventriculograms. Transmural infarctions were akinetic, showing no change in thickness throughout the cardiac cycle. Hypokinetic segments distal to high-grade coronary stenosis were common, although most segments distal to stenosis contracted normally. Reversal of segmental contraction abnormalities by coronary bypass grafting was shown in three subjects, while worsening of function was seen in previously abnormal segments in two and in a previously normal segment in one subject. Epicardial echocardiographic mapping is a practical method for intraoperative assessment of myocardial function during coronary surgery in man that may enhance our understanding of the pathophysiology of coronary disease and the effects of coronary surgery.
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PMID:Epicardial mapping of segmental myocardial function: an echocardiographic method applicable in man. 698 15

Lack of physical activity appears to have deleterious effects on serum lipoproteins. Twenty-three patients who were completely immobilised by traumatic fracture of the spine had significantly lower (P < 0.001) plasma high density lipoprotein cholesterol (HDL-C) and apolipoprotein A-I levels than normally mobile paired control subjects. The low density lipoprotein cholesterol (LDL-C) levels of the immobile patients were not different from those of controls but the LDL triglyceride (LDL-TG) of the patients was increased. The patients had a significantly higher LDL/HDL-C ratio and HDL-C/apoprotein A-I ratio than the controls. These results suggest that the increased risk of ischemic heart disease in physically inactive people is partially accounted for by low plasma HDL levels. On the other hand, caution is needed in the interpretation of HDL findings in clinical conditions where the physical activity of the patients is limited.
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PMID:High density lipoprotein and apolipoprotein A-i during physical inactivity. Demonstration at low levels in patients with spine fracture. 745 90

Hypokinesia is not an independent risk factor of ischemic heart disease (IHD) but it contributes to progression of this disease because of a positive correlation with such risk factors as arterial hypertension, dislipoproteinemia, obesity, hyperinsulinism, diabetes mellitus type 2. This dictates the necessity to add exercise to pharmacotherapy of IHD. Combined treatment of IHD including bicycle exercise in the free load regimen significantly improves cardiac pump function--a 32.0 and 34.7% mean rise in stroke index and ejection fraction in patients under 60 years of age, respectively. The above rise does not depend on the initial condition of hemodynamics. There are cases when the increase is the highest in patients with the least baseline indices showing the presence of adaptive reserves which realize in physical training. The patients treated had no complications. Thus, use of the above bicycle exercise in IHD patients can be recommended for hospital rehabilitation.
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PMID:[Bicycle exercise in the free load regimen and hemodynamics in inpatients with ischemic heart disease]. 1714 51