ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

摘要:

Ethacrynic acid, a chemically different diuretic, has been evaluated in 82 patients. The drug was remarkably potent when administered intravenously (0.5 to 1 mg./Kg.) or by mouth (doses to 50 mg. four times per day). It proved particularly effective in patients with refractory edema, and in edematous states accompanied by azotemia or electrolyte disturbances. Its natriuretic effects added to those of other diuretics and potentiation actually appeared to occur when it was combined with a carbonic-anhydrase inhibitor.Renal clearance data indicated that ethacrynic acid has a unique mode of action. There was little effect on glomerular filtration or renal plasma flow and its major action was to block sodium and chloride reabsorption probably in both proximal and distal portions of the renal tubules.Ion exchange mechanisms seemed little affected by the drug because it characteristically increased both hydrogen and potassium ion excretion. In general the degree of induced potassium loss correlated well with the rate of endogenous aldosterone secretion. Furthermore, ethacrynic acid did not cause potassium loss in one adrenalectomized subject nor in another subject pretreated with an aldosterone antagonist.Diuresis induced by ethacrynic acid was often accompanied by the development of systemic metabolic alkalosis. Factors in the development of this alkalosis were (1) urinary K+loss with hypokalemia, (2) urinary H+loss, and (3) in edematous patients the rapid large loss of relatively HCO3--free fluid from the extracellular fluid space. The systemic alkalosis was found to be accompanied by compensatory alveolar hypoventilation. These studies of the mechanisms of the alkalosis point to the occasional importance ofthe administration of chloride, of potassium, or of saline as corrective measures.Diuresis with ethacrynic acid, like other diuretic agents, produced marked increases in the rate of aldosterone secretion of normal subjects. More variable effects were observed in patients with heart disease, possibly because improvement in their circulatory status operated to lower hormone secretion activity.Ethacrynic acid had effects on urate excretion that resembled thiazide diuretics. Higher blood levels of intravenous administration were uricosuric. Lower blood levels of oral therapy caused renal urate retention and hyperuricemia.Most of the problems associated with the use of ethacrynic acid appeared to be related more to its pharmacologic potency than to any truly toxic effect. Because of this it is suggested that the sensitivity and response pattern of each patient be determined in stepwise fashion. In most patients with edema an intermittent dosage schedule provides a more efficient diuretic response and allows time intervals for correction of any electrolyte imbalance. If used with a thorough understanding of its pharmacologic effects ethacrynic acid promises to be a most useful agent in the therapy of patients with difficult or refractory edema.

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

摘要:

Smoking by subjects with healed myocardial infarction, in contrast to its effects on thenormal subject, fails to provoke an increase in cardiac output or in stroke volume. On the other hand, smoking does increase the heart rate in subjects with healed myocardial infarction. This dissociation between the effect on heart rate and on cardiac output and stroke volume, which was also noted in the healthy subject pretreated with glucose, indicates that increase in heart rate is mediated by different factors than those that increase stroke volume and cardiac output.

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

摘要:

This Study demonstrates the feasibility of developing an analog computer model of the electrical events of the heart, based on a rational application of experimental knowledge of ventricular depolarization.Not only did the results resemble normal vectorcardiographic loops, but also changes were analogized from concepts of pathologic physiology that produced configurations resembling known clinical vectorcardiographic abnormalities.It is expected that all known vectorcardiographic deviations can eventually be simulated on a rational basis, and, further, that previously unrecognized alterations may be found permitting diagnosis of infarction or other processes not possible by present knowledge and criteria.The present study strongly supports the view that most, if not all, of the factors known to influence the electrical field of the heart can be simulated by computer technics. When this is accomplished, it may be possible to remove much of the dogma and empiricism from traditional electrocardiographic theory and place it on a more rational foundation. The need for further exploration in this area seems imperative.

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

摘要:

Four hundred fifteen patients with interventricular septal defect, proved at cardiac catheterization, have been followed for 1,407 patient years. As a group, they demonstrated marked growth failure in early childhood, which was more striking for weight than height. Ninety patients had serial hemodynamic studies without intervening cardiovascular surgery. Eight demonstrated spontaneous functional closure of their defect; only one progressed to the Eisenmenger syndrome. No patient with initially normal pressure developed pulmonary hypertension. Patients with initial pulmonary hypertension more commonly demonstrated regression than progression of the hypertension. Six patients developed bacterial endocarditis; all recovered. There was a frequent association (11 per cent) between interventricular septal defect and right ventricular outflow obstruction. Some patients developed increasing right ventricular outflow obstruction during the study. Eighteen patients with predominant right-to-left shunt were studied. Seventeen were cyanotic at the time of the initial study. The incidence of cyanosis was equal in the two sexes but females developed it later in life than males.Twenty-nine patients have died. Twenty-two deaths resulted from operative procedures; seven from the natural course of the disease. The principal factors associated with operative mortality was the presence of pulmonary hypertension and surgical repair before age 5. There were no operative deaths in patients with pulmonary artery systolic pressure below 65 mm. Hg. One patient died of progressive pulmonary hypertension 6 years after successful surgical closure of his defect.There is a great need for more information concerning the natural course of this disease in all age groups, both in the unoperated patient and in patients whose defects have been surgically closed.

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

摘要:

A large series of patients with cyanotic congenital heart disease and inadequate pulmonary blood flow who required a systemic to pulmonary artery anastomosis was reviewed, along with a small current series of patients unselected as to surgical intervention.Thirty-eight per cent of 190 patients in the first group had definite spells consisting of paroxysmal hyperpnea and increased cyanosis, frequently progressing to loss of consciousness. In the current group, 13 of 24 had spells. In the combined groups, there were three convulsions, eight cerebral vascular accidents, and six deaths due to the spell.Age of onset varied from 1 month to 2 years, with the peak incidence between 2 to 3 months of age. The time of day at which spells occurred was recorded in only 15 patients in the large series: 11 occurred in the morning and four in the evening. In the smaller series, the patients who had only occasional episodes had them exclusively in the morning, whereas the severely affected patients had attacks at almost any time.Precipitating factors, in order of over-all frequency, were crying, defecation, and feeding.The most surprising finding was the lack of correlation of hyperpneic spells with resting arterial desaturation, although all arterial saturations obtained during attacks were quite low. Two patients with observed, typical paroxysms had arterial saturations under sedation of 93 and 98 per cent, in contrast to a patient with a 44-per cent saturation who had had no spells.

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

摘要:

Various sets of QRS voltages that are used in the diagnosis of left ventricular hypertrophy were determined from the electrocardiograms of 300 normal men judged to be free from cardiopulmonary disease, and these were correlated to body build expressed in terms of ponderal index. A correlation was found for all voltages studied and a highly significant correlation was found for the criteria “RI+ SIII” “greatest R + greatest S in the precordial leads” and “greatest R + S ina single precordial lead.” Age or activity did not appear to be specific factors in the population studied. Graphs were constructed for the latter three sets of voltages defining upper limits of normal for various values of the ponderal index. By using these sets of voltage criteria in conjunction with this index, one would hopefully improve both accuracy and specificity in the electrocardiographic diagnosis of early left ventricular hypertrophy.

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

摘要:

The analysis and description of the preoperative and postoperative vectorcardiograms in tetralogy of Fallot are presented. The spatial orientation of the maximum QRS vectors to the right, anteriorly, and inferiorly in group I is indicative of right ventricular hypertrophy. In group II patients, the vectorcardiogram showed evidence of increased electrical activity of the left ventricle.Vectorcardiographic patterns of complete right bundle-branch block were noted in nine patients in group III.

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID