Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018799 (heart disease)
 34,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

During aortic clamping, drug protection of the myocardium, far from supplanting hypothermia, complements it, particularly in the case of left ventricular hypertrophy. Ultramicroscopy and new techniques of histobiological exploration of the myocite have enabled one to distinguish the lessions provoked by anoxia from those induced by reperfusion. At present, drug protection, extended to energetic solutions and electrolytes, aim at preserving energy metabolism by stocking of the substrate and at avoiding interferences which precipitate exhaustion of the adenosine triphosphate and phosphocreatinine reserves. In order to do this, hemodilution in particular is limited in subjects with decompensated cardiopathy; choice of anesthetics is orientated towards neuroleptanalgesia or fluothane, and it is attempted to neutralize the adrenergic reaction by the use of beta-blocking substances. Furthermore, it is preferred to interrupt electrogenesis at the stage of polarization: depolarizing cardioplegic solutions rich in potassium and sodium are rejected and in preference membrane stabilizers are used (procaine, magnesium, tetrodoxine...) The ultramicroscopic analysis of the structural modifications leads to sparing of the integrity of the lysosomial membrane by corticoids and alkalines. The use of calcium is deferred, anti-calcium techniques are even proposed (washing poor in calcium, verapamil). Cellular edema is prevented and treated by solution (mannitol - sorbitol) whose osmolarity must be less than 300 M osm/l. A conditioning of the biochemical and physicial structures and of cardiac work is being more and more thought of which leads to the classification of beta stimulating substances as negative, and their indications must be seriously thought of and used with reserve.
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PMID:[Drug protection of the myocardium during cardiac surgery]. 1 31

Insulin accelerates the entry of glucose and amino acids into muscle cells by acting upon the 'carrier-facilitated' transport mechanism. For glucose this process is passive and leads to equilibration of intracellular and extracellular concentrations. In heart muscle, glucose transport is a rate-limiting step for glucose uptake. During hypoxia and ischemia the heart turns to anaerobic glycolysis for energy production and therefore, maximal glucose transport becomes important. Insulin is necessary to insure proper protein synthesis, probably at the level of membrane-bound polyribosomes. However, during myocardial hypoxia, insulin alone cannot restore the associated depression in protein synthesis. Although insulin hyperpolarizes the cell, a change in the ratio of intracellular to extracellular activities of potassium is not its primary mode of action. An insulin-induced configurational change in the plasma membrane could simultaneously account for the effects of insulin on sodium and potassium permeability and the action on facilitated transport. Intracellular levels of cyclic adenylate may be reduced by insulin in adipose tissue because of inhibition of adenyl cyclase or stimulation of phosphodiesterase. However, at this time there is little evidence that insulin alters cyclic AMP levels in the heart. Insulin secretion is depressed in patients with heart disease in proportion to the reduction of cardiac index sustained. Since the ischemic heart is dependent upon glucose as the major fuel, insulin lack may deprive the heart of adequate substrate.
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PMID:Insulin: fundamental mechanism of action and the heart. 18 67

The field of myocardial perfusion imaging has made many advances but still is in its infancy. The limitations in the technology at this time include limited instrument resolution of 6-9 mm, intrinsic at the energy of the mercury x-ray; significant Rayleigh scatter, which is particularly distrubing because this scatter cannot be removed by pulse-height analysis; and an effective half-life of thallium in the myocardium, which makes repeated imaging over a short period of time very difficult. Although hopes for the development of a technetium-labeled myocardial imaging tracer have burnt brightly, no new agents are presently in sight. Resolution with a technetium-labeled tracer would almost double that of thallium, and the dose that could be administered to the patient would increase by at least a factor of 4. The effective half-life of the tracer in the myocardium would permit multiple images to be obtained at least in the same day. Even with the limitations of the current techniques, however, myocardial perfusion imaging can make a real contribution to the care of the patients with heart disease. Thallium is now produced commercially and reasonably easily obtained. Extraction of thallium by the myocardium is probably somewhat, but not exactly, analogous to potassium. The tracer has major applications in defining shape and size of the heart, thickness of muscle, and especially myocardial ischemia and infarction. This review is aimed at providing a current perspective of these uses.
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PMID:Thallium-201 as a myocardial imaging agent. 31 35

Potassium deficiency is an important complication in the treatment of heart disease. However, there is a serious dichotomy in the literature. Severe potassium depletion has been reported in this condition when exchangeable potassium was measured whereas normal levels or marginal depletion were found in measurements of total body potassium. To clarify this situation, simultaneous measurements of total body potassium by whole-body counting, and of exchangeable potassium by isotope dilution using 43K, were made in 10 male subjects with established airways obstruction. Sequential determinations showed that exchangeable potassium increased up to 68 hours after administration, and values obtained at only 24 hours would have been a substantial underestimate. In this group of subjects neither total body nor exchangeable potassium at 48 hours was significantly different from the expected normal value.
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PMID:Total body and exchangeable potassium in chronic airways obstruction: a controversial area? 41 19

High potassium together with low sodium in diet and intravenous fluids has been observed clinically by Sodi-Pallares to have a beneficial effect on chronic heart failure and on acute myocardial infarction. Recent studies from the laboratory of Ling indicate that high potassium, low sodium environments can partially restore damaged cell proteins to their normal undamaged configuration. It follows that by this mechanism cell proteins damaged by the chronic or acute hypoxia of heart disease are probably partly repaired when high potassium, low sodium therapy is used.
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PMID:Successful therapy of heart disease by high potassium together with low sodium in accord with predictions from the associated cation, structured water concept of the cell. 50 67

To assess the relation of hyperaldosteronism and potassium depletion to the intensity of diuretic therapy we have measured plasma aldosterone by radioimmunoassay and total exchangeable potassium by radioisotope dilution in 24 patients when they were stable at the end of their preparation for cardiac operation. Some patients required intensive frusemide therapy to reach an optimal state for operation and many showed hyperaldosteronism. Plasma aldosterone was significantly related to daily dose of frusemide (r=0.77). Depletion of total exchangeable potassium expressed in terms of predicted weight was significantly related to plasma aldosterone (r= -0.64). The reduction in total exchangeable potassium is interpreted as chiefly related to loss of lean tissue mass from the wasting that leads to cardiac cachexia, but evidence is presented on the basis of measurements of extracellular fluid volume as sulphate space (20 patients) of entry of sodium into the cells which may indicate a true cellular potassium loss. Although plasma potassium is usually easily maintained with oral potassium supplements or aldosterone antagonists, we postulate that intensive diuretic therapy in severe heart disease may provoke hyperaldosteronism which accentuates potassium loss and may contribute to wasting and to intracellular potassium depletion in critical tissue, such as myocardium.
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PMID:Relation of plasma aldosterone concentration to diuretic treatment in patients with severe heart disease. 50 54

Exercise ECGs (bicycle ergometry in recumbency) were obtained in 252 women (aged 20-49 years) without evidence of organic heart disease. In 51 (20%) there was a false-positive change in the ECG with horizontal or descending S-T depression greater than or equal to 1 mm. The frequency of this change increased with increasing age. In group I (20-29 years) it was 5%, in group II (30-39 years) 20%, in group III (40-49 years) 38%. In 34 of the 51 women abnormal repolarisation changes were present even at rest. The S-T depression during exercise in most cases amounted to less than 2 mm and often occurred only on maximum exercise during the first or second minute of the recovery phase. These "ischaemia" changes disappeared in 29 of 41 women after administration of 100 mmol potassium chloride. Nine of 12 women in whom the positive ECG signs persisted after KCl, coronary angiography failed to demonstrate any abnormalities.
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PMID:[False-positive exercise ECG in women without organic heart disease (author's transl)]. 64 56

The study was performed on 612 routine cultures of material obtained from root canals of teeth at the time of filling (r-cultures) by students at the Department of Endodontics during a continuous period of one year. Twenty-nine isolates from 27 (29.3%) of the 92 positive cultures filled the criteria of enterococci (Sherman, 1937) and had demonstrable group D-antigen. With a set of tests these isolates were identified as follows: Strep. faecalis subsp. faecalis (10), Strep. faecalis subsp. zymogenes (3), Strep. faecalis subsp. liquefaciens (8), atypical variants of Strep. faecalis (6), Strep. faecium var. faecium (1) and Strep. faecium var. durans (1). Five tests in the present study clearly differentiated Strep. faecalis from Strep. faecium i.e. fermentation of sorbitol, glycerol (anaerobic) and melezitose, tolerance to potassium tellurite (0.1%) (positive for Strep. faecalis) and production of hydrogen peroxide (positive for Strep. faecium). In the inocula 10(3) or more colony forming units of enterococci were found more often of other identified microorganisms. This means that enterococci are of special interest in studies on the influence of infection at the time of filling of root canals on the prognosis of root canal therapy. The isolates were also tested for susceptibility to azidocillin, ampicillin, penicillin-G, penicillin-V and erythromycin with the paper disc method. All the isolates were susceptible to azidocillin and ampicillin (sensitivity group I), while the majority of the isolates showed a lower susceptibility to the other three antibiotics (sensitivity group II). The significance of these findings in the choice of prophylactic antibiotic to prevent bacterial endocarditis in patients with a history of rheumatic or congenital heart disease are discussed, when bacteremia from dental procedures may be expected.
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PMID:Streptococcus faecalis and Streptococcus faecium in infected dental root canals at filling and their susceptibility to azidocillin and some comparable antibiotics. 81 Jul 53

To study myocardial metabolism in chronic hypoxia due to cyanotic congenital heart disease, coronary arteriovenous differences of lactate (L), pyruvate (P), inorganic phosphate (Pi) and potassium (K) were measured in 14 cyanotic patients and seven controls, at rest and during atrial pacing. At rest, there was no difference in any parameter between cyanotic and noncyanotic patients. During atrial pacing (150-175/min) for 10 min, a moderate drop in L-extraction occurred in the control patients with some increase in L/P ratio in coronary venous blood. Cyanotic patients fell into two groups: in nine (group I), the arterial oxygen saturation (SaO2) dropped with pacing. Their L-extraction fell sharply, from 28.1 +/- 3.12 to --2.8 5.51 and L production occurred in five. There was a significance increase in coronary venous L/P ratio. Five cyanotic patients (group II) showed no drop in SaO2 with pacing, and L extraction as well as L/P ratio remained stable. Uptake of Pi was noted in all patients at rest, during pacing this disappeared in controls and group I cyanotics but not in group II. No K changes were seen in any patient. Thus, myocardial metabolism is normal at rest in patients with cyanotic CHD; during atrial pacing, a shift toward anaerobic metabolism occurs if SaO2 drops; cyanotic patients whose SaO2 remains stable appear to withstand pacing better than controls.
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PMID:Myocardial metabolism in cyanotic congenital heart disease studied by arteriovenous differences of lactate, phosphate, and potassium at rest and during atrial pacing. 83 11

1. A study was made of 34 cases (33%) of myocardial infarction trans and immediately postoperative which occurred in 11,210 surgical interventions with and without extracorporeal circulation. 2. This presents a statistical relation of the frequency of myocardial infarction in realtion to the heart disease acquired with or without extracorporeal circulation with the mitral, aortic, and double prosthesis of the mitral and aortic valves. A correlation was also made with the ischemic heart disease subjected to revascularization. The same analysis was carried out in the congenital heart disease with or without extracorporeal circulation. 3. In all cases the antecedents, precipitating factors, and the clinical picture were studied and in 12 cases the necropsy was analized. The principal finding was transmural myocardial infarction with electrocardiographic proof and serial enzymes. 4. The group was divided into two sub-groups; Group "A" with acute myocardial infarction transoperative, and Group "B" with acute myocardial infarction in the first eight postoperative days. The electrical and mechanical complications were analized. 5. A correlation was made of the causes of mortality related to the type of congenital or acquired heart disease with or without extracorporeal circulation. 6. The frequency of this entity was studied with the total time of aortic clamping, and the complications such as the low cardiac output syndrome, rupture of the wall, aneurysms, acute pulmonary edema, and with the disturbances of rhythm and conduction. 7. The presence of 33.3% of normal coronaries in these of necropsy was emphasized. 8. The importance of the coronary profile of this group in relation to the consequences of a stress from anesthesia, surgery, extracorporeal circulation, and aortic clamping is mentioned. 9. The diagnostic parameters such as arterial hypotension with or without the low cardiac output syndrome, enzyme levels, and the action of the potassium ion are mentioned. 10. An analysis is made of the possible etiological factors of the precipitation of the myocardial necrosis in the cases with normal coronaries and those in which there was no important obstruction of the coronary macrocirculation. 11. In the subgroup "A" it was found that the frequency of myocardial infarction was less than in the subgroup "B", but there was greater mortality in group "A". The possible causal factors are analized.
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PMID:[Trans and postoperative myocardial infarct in heart surgery]. 93 52


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