Showing papers on "Cardiac arrhythmia published in 1974"

Cardiac trauma: Clinical and experimental correlations of myocardial contusion.

Abstract: Clinical and experimental observations in myocardial contusion have been correlated. Cardiac arrhythmia is always an important consequence and may be fatal. Reduction in cardiac output often accompanies significant cardiac injury. The coronary arterial circulation is not interrupted and is generally enhanced to the area of injury. Healing of the injury under these circulatory conditions may result in patchy scarring and peculiar adynamic areas of myocardium. Early diagnosis of myocardial contusion may be aided using radionuclide imaging with (99m)Tc-Sn-polyphosphate.

The effects of human contact on cardiac arrhythmia in coronary care patients.

Abstract: It is part of common wisdom that interactions between a doctor or a nurse and a patient can modify patients's cardiac activity. However, the ubiquity of that knowledge has tended to obscure recognition of the fact that the magnitude, generality, and mechanisms of the cardiovascular effects of human contact are poorly understood. To explore the effects of human contact on the heart activity, coronary care patients were studied by noting on a continuous electrocardiogram each time any person came in contact with the patient. Results of these studies have shown that human contact, can have major effects on cardiac function of coronary care patients. These effects include phenomena such as heart rate changes of over 30 beats/minute, a doubling of the frequency of abnormal heart beats, and major changes in the conduction of electrical impulses in the heart and may take place with such routine clinical interactions as pulse taking and comforting behavior. Similar responses to human contact observed in patients on a shock-trauma unit who were paralyzed with d-tubocurarine suggest that such responses are central in origin, are not dependent on changes in respiration or movement, and can occur in subjects without pre-existing cardiac pathology. Moreover a number of studies over the past decade have shown that human contact can have major effects on the cardiovascular functioning of healthy animals, including dogs and horses These results indicate the need for quantification of the phyciological effects of many kinds of clinical interactions and the necessity for specification of ongoing human interactions accompanying epidemiological studies of the frequency of arrhythmia in coronary patients of the effects of antiarrhythmic drugs on that frequency. Although the extent and responsible mechanisms for such effects are not yet fully known, additional studies are currently underway aimed at uncovering such knowledge.

Lithium toxicity and refractory cardiac arrhythmia treated with intravenous magnesium.

Abstract: A case of refractory cardiac arrhythmia induced by lithium and controlled by intravenous magnesium sulphate is describedThe mechanism of action of the magnesium in controlling the arrhythmia is dis...

Letter: E.C.T. and cardiac arrhythmia.

Abstract: la-ter pane S-T segmient depres-sion was stil evident (fig.ic) despite the prespence of normial myocardial lactate extraction (+13 mg/100 m) at this time. It could be considered -that increased coronary arterial perfusion resul-ted fromn the trinitrin therapy and produced a wash-th-rough effect, thoereby' preventing proper evalutiaon of myocardial lactate extract-ion status. Howevetr, after a further five-minute period spontaneous angina recurred, with further plane S-T segment depression (fig Id) and zero myocardial lactate extraction. Five minutes after a second trinitrin tablet had been given s~nposwere relieved comipletely~andthi's was associated with norm-al myocardial lactate extraction (+11nig/ 100 ml) despite the persistence of plane S-T segment depression (fig. le). It was only after a furth-er 20 minute-s had elapsed, during which the patient remained asymnptomatic w-ith normal myocardial lactate extraction (+ 1-2 rig/ 100 ml), that the S-T segment regained its pree vious-ly accepted normal J-,point position (figd I) I am, etc., BRIAN LIVELEY King's College Hospi-tal, London S5 l

E.C.T. and Cardiac Arrhythmia.

Abstract: controlled studies of heparin treatment versus supportive treatment, but a review of the available literature' strongly suggests that in most published series heparin has been of value in the treatment of the haemolyticuraemic syndrome. The use of thrombolytic therapy in the haemolytic-uraemic syndrome cannot be assessed simply by selecting those patients who have failed to respond to conventional therapy over prolonged periods or who present after some weeks of treatment at another institution. Such patients are obviously a selected group in whom improvement or cure from any form of therapy is most unlikely. Furthermore, the efficacy of thrombolytic therapy cannot be assessed only on the basis of reduction of mortality during the acute phase of the disease. In this sense it is particularly relevant that 52%/0 of the children described by Gianantonio et al.' had a high incidence of residual renal abnormalities, and we have observed similar findings (see table).3 The reduction of long-term sequelae of the haemolytic-uraemic syndrome reported by Monnens et al.4 and by Powell and Ekert5 is a strong indication for the use of thrombolytic therapy in this disease. There seems little to be gained from conservative management during the acute phase of the illness when probably half of the children may end up as renal cripples. Four lines of evidence have been used to indicate that the haemolytic-uraemic syndrome is the clinical counterpart of the Schwartzman reaction, in which repeated sublethal triggers produce a hypercoagulable state with fibrin deposition. These are: (1) occurrence of impaired renal function and a haemorrhagic tendency in both circumstances; (2) fragmentation of red cells and thrombocytopenia in both circumstances; (3) fibrin deposition in the renal arterioles and glomerular capsules with partial or complete cortical necrosis; and (4) response to anticoagulants. It is clear from experimental work that the Schwartzman reaction can be prevented by heparin if it is given early. Likewise, thrombolytic therapy can prevent the Schwartzman reaction if given within four hours of the provocative injection of the triggering agent. Thus the selection of patients for anticoagulant and thrombolytic therapy on the basis of failed response to conservative treatment will ensure that very few, if any, will obtain benefit from this form of treatment. -I am, etc.,

Cardiac Sensitization Studies in Dogs with Myocardial Infarctions.

Abstract: : In man, myocardial infarction is the most serious form of ischemic cardiovascular disease and, because of its frequent occurrence, it is the single most important type of heart disease. Since myocardial infarction is common in the human population, the authors attempted to determine whether such a condition might place an individual, exposed to high halocarbon concentrations, at greater risk from an epinephrine-induced cardiac arrhythmia. Such exposure conditions could occur in the chemical industry, or in the refrigeration and aerosol industries. Using the dog as an animal model for myocardial infarction, results imply that such an individual, having recovered from myocardial infarction and able to return to work, may be at no greater risk from cardiac sensitization than the normal healthy individual.