bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on Coumarin Anticoagulant Drugs
Authors: O'REILLY ROBERT A. , AGGELER PAUL M. 
Published: June 2012

Thirty normal subjects were given a single loading dose of warfarin sodium, 1.5 mg/kg of body weight. The drug was metabolized slowly (mean biological half-life, 47 hr) and showed a prolonged biological effect (over 6 days). In two separate experiments no loading dose was given; instead, daily doses of 15 mg and 10 mg were administered to 15 of the subjects. The prothrombin complex responses were compared with those obtained in the same subjects after the large loading dose. The mean time in days to reach the therapeutic range (prothrombin complex activity<35% of normal) was 1.1 days with the dose of 1.5 mg/kg of body weight, 2.7 days with the dose of 15 mg/day, and 5.2 days with 10 mg/day. With all three methods the therapeutic range was reached soon after a level of warfarin of 2 mg/L plasma was attained.
The rates of fall of the four vitamin K-dependent clotting factors (II, VII, IX, and X) with the large loading dose and with the daily dosage of 15 mg were compared in six of the subjects. With the loading dose, factor VII activity was less during the first 48 hr, but there was no other significant difference between the two methods of drug administration in the amount of reduction of any of the four factors.
Since the role of factor VII in thrombogenesis is questioned, these results provide a rational basis for the induction of prophylactic anticoagulant therapy without large loading doses of warfarin. Avoidance of the customary loading dose should reduce the danger of hemorrhage, particularly in patients who are sensitive to the drug because of advanced age, sepsis, liver disease, congestive heart failure, or recent surgery or trauma.
Atrial Septal Defect
Authors: RAHIMTOOLA SHAHBUDIN H. , KIRKLIN JOHN W. , BURCHELL HOWARD B. 
Published: June 2012

A total of 696 patients with atrial septal defect (ASD) of either the secundum (90.5%) or the sinus venosus (9.5%) type were operated on at the Mayo Clinic from 1954 through 1965. Pulmonary hypertension (PHT, defined as pulmonary artery systolic pressure of 60 mm Hg or greater) or chronic congestive cardiac failure (CCF) (or both) was associated with 80% of the hospital deaths. For the years 1958 through 1965 (531 cases), the hospital mortality for these three groups was 10% (three of 30), 14% (one of seven), and 18% (two of 11), respectively; only two (0.4%) of the remaining 483 patients died, and both were more than 45 years old (among a total of 93 patients more than 45 years old). There have been no operative deaths among those less than 45 years of age and without PHT or CCF (390 cases) in the years 1958 through 1965. No operative deaths occurred in the years 1963 through 1965. Of 16 patients 60 years or older (1954 through 1965), one has died.
A 6- to 12-year follow-up was possible on 397 patients operated on from 1954 through 1960. In the absence of PHT or CCF, 330 survived operation. Among the 53 patients more than 45 years old, four died later (not definitely related to closure of ASD), three were not well, 32 were in excellent health, and 14 were lost to follow-up in 1966. Among the 277 patients less than 45 years old, 10 died later (all but one probably unrelated to closure of ASD), three were unwell, 186 were in excellent health, and 78 were lost to follow-up in 1966.

Forty-two patients with PHT survived operation in the period from 1954 through 1960. Ten had pulmonary resistance of more than 640 dynes sec cm
-5
; four of these were well, two had died (with PHT), two had severe PHT, one was in CCF, and one was moderately disabled. Thirty-two had pulmonary resistances of 640 dynes sec cm
-5
or less; three of these had died (unrelated to closure of ASD), five were moderately disabled, 16 were in excellent health, and eight were lost to follow-up in 1966.

Eighteen patients with CCF survived operation in the period from 1954 through 1960. All had had grade IV disability (New York Heart Association classification). There were three late deaths (one due to severe pulmonary vascular disease and two unrelated to closure of ASD), one patient had grade IV disability, five had grades I to II disability, eight were in excellent health, and one was lost to follow-up in 1966.
Paroxysmal arrhythmia occurred in 75 of 397 patients (19%) operated on from 1954 through 1960. In 53 patients it was present preoperatively and persisted postoperatively in 15 of them (28%); in an additional 22 it appeared for the first time after closure of the ASD.
Hemodynamic Effects of Artificial Pacing in Complete Heart Block Complicating Acute Myocardial Infarction
Authors: LASSERS B. W. , ANDERTON J. L. , GEORGE M. , MUIR A. L. , JULIAN D. G. 
Published: June 2012

The hemodynamic changes associated with complete heart block complicating acute myocardial infarction and the effects of artificial pacing at various rates on these measurements were studied in 13 patients. Studies were performed on the first day of complete block in all patients and were repeated on subsequent days in six.
With two exceptions cardiac output was increased by pacing. In patients paced at progressively increasing ventricular rates, the rate associated with the maximal cardiac output exceeded 100/min, with one exception. However, an adequate response usually occurred between 80 and 90/min. Stroke volume fell as the rate was increased with pacing in most patients, but rose in some, suggesting improved myocardial performance. Systemic blood pressure increased, and the change paralleled cardiac output changes fairly closely as pacing rates were increased. The blood pressure did not, however, reflect reliably the absolute level of cardiac output either in heart block or after the return of sinus rhythm. Systemic vascular resistance was high in most patients with low cardiac outputs and fell with pacing at maximal output rates. There was no consistent change in mean right atrial or mean pulmonary arterial pressure with pacing during the period of study. Tension time index was low in heart block, and increased considerably with pacing, implying a corresponding increase in myocardial oxygen requirements.
Pacing improved signs of depressed mental function and poor skin circulation which were invariably associated with a severe reduction in cardiac output. These signs were found to be superior to heart rate and blood pressure in clinical evaluation of the adequacy of the cardiac output in heart block and the response to pacing.
Relationship Between the Plasma Level of Diphenylhydantoin Sodium and Its Cardiac Antiarrhythmic Effects
Authors: BIGGER J. THOMAS , SCHMIDT DONALD H. , KUTT HENN 
Published: June 2012

The effect of diphenylhydantoin sodium (DPH, Dilantin) on a variety of arrhythmias was studied in relation to its plasma levels. DPH was administered in one of three ways: (1) multiple intravenous doses, (2) single intravenous doses, and (3) oral doses. Ventricular arrhythmias occurring in many clinical conditions and atrial tachycardia, particularly if caused by digitalis excess, responded well to treatment with DPH. Three fourths of the responsive arrhythmias were abolished at plasma levels of DPH of 10 to 18 µg/ml. In most cases a critical, effective plasma level could be demonstrated; this level had to be exceeded in order to suppress the arrhythmia being treated.
A method of rapidly effective oral therapy of arrhythmias with diphenylhydantoin is described, and a method of transition from intravenous to oral therapy is demonstrated.
The antiarrhythmic action of diphenylhydantoin was accompanied by neither depression of sinoatrial nodal activity nor atrioventricular or intraventricular conduction disturbances, but was accompanied by a shortening of the Q-T interval. Hypotension accompanying the intravenous use of this drug was minimized by administration of the full dose in increments.
Detection of Heart Disease in Children 1919-1967
Authors: HENIKOFF LEO M. , STEVENS WILLIAM A. , PERRY LOWELL W. 
Published: June 2012

Since 1959, auscultation by physicians in screening 49,496 school children has yielded 4.5 cases of heart disease/1,000 students screened. Sensitivity by analysis of "inserted" cases averages 64%, but varies with capabilities of examining physicians.
X-ray and ECG evaluations on smaller populations have yielded, respectively, 2.7 and 2.8 cases/1,000 children screened, and sensitivity results average 30 to 40%.
The tape-recorded heart sounds technique has yielded 2.9 cases/1,000 in screening 188,925 children. Sensitivity by analysis of "inserted" cases averages 75% and, in the population of "naturally occurring" heart disease, 56%.
In 23,148 school children, an analog-digital device (PhonoCardioScan) has yielded 4.8 cases/1,000 children screened. Of "inserted" cases, 69% have been detected. Sixtyfour to 80% of "naturally occurring" cases have been detected.
With each technique, approximately 40% of the heart disease detected had been previously unknown. The specificity of these methods ranges from 95 to 99%.
For primary screening the analog-digital device is the most effective currently available alternative to examination by cardiologists.
Transposition of the Great Arteries
Authors: RASHKIND WILLIAM J. , MILLER WILLIAM W. 
Published: June 2012

A nonsurgical method of creating atrial septal defects using a balloon catheter has been reviewed, and important procedural and technical details have been presented. The results of balloon atrioseptostomy in 31 infants with transposition of the great arteries have been reported and compared with those from the surgical creation of atrial septal defects. All 31 patients survived balloon atrioseptostomy without complications; 26 of them (84%) had effective immediate palliation, and 22 (71%) are long-term survivors. These results demonstrate that effective palliation of transposition of the great arteries, with or without associated ventricular septal defect, can be provided rapidly and safely by balloon atrioseptostomy. All patients with transposition and a large ventricular septal defect should have balloon atrioseptostomy and may also need pulmonary artery banding. For some of these patients banding may be postponed safely for many months, may occur spontaneously, or may be avoided completely.
Atrioseptostomy by the balloon catheter technique requires neither sedation nor general anesthesia, and obviates the need for thoracotomy and cardiotomy. The rapidity with which it can be performed makes it particularly advantageous for the desperately hypoxic newborn with transposition of the great arteries who may be considered too sick to withstand major surgery.
An Attempt at the Assessment of Myocardial Contractility from Phonocardiographically Measured Time Components of Ventricular Contraction in Patients with Prosthetic Aortic Valves
Authors: BECK W. , SCHRIRE V. 
Published: June 2012

The phonocardiographically recorded time interval between the first heart sound and the mid-ejection point is a rough guide to the time interval between the onset and the peak ventricular pressure in patients with the University of Cape Town aortic valve prosthesis. This time interval is insensitive to changes in stroke volume and aortic pressure produced by variations in ventricular filling and may be used to show changes in contractility in any one patient.
In a group of 42 patients with 64 postoperative phonocardiograms, mid-ejection time varied between 140 and 250 msec. A strong negative correlation with heart rate, and a strong positive correlation with the width of the QRS complex were present without any significant correlation with heart size or with other estimates of left ventricular function.
It is suggested that in the abnormal myocardium, ventricular asynchrony may seriously interfere with the velocity of the ventricular contraction invalidating the assessment of contractile element velocity from the velocity components of the ventricular pressure pulse.
Cardiac Surgery in Bacterial Endocarditis
Authors: STASON WILLIAM B. , DESANCTIS ROMAN W. , WEINBERG ARNOLD N. , AUSTEN W. GERALD 
Published: June 2012

Open heart surgery has been performed at the Massachusetts General Hospital in 13 patients less than 6 months after the initiation of treatment for acute or subacute bacterial endocarditis. The endocarditis involved the aortic valve in 12 cases and a mitral valve prosthesis in the other. In two patients there was concomitant rupture of chordae tendineae of the mitral valve. One patient received no preoperative antibiotics, and four were still receiving their initial course of therapy at the time of surgery. The primary indication for surgery in all cases was progressive or intractable congestive heart failure. Ten underwent replacement of the aortic valve alone, two had both aortic and mitral valves replaced, and one had a mitral prosthesis replaced.
Of the 13 patients, 10 are alive and doing well, although paraprosthetic insufficiency developed in three, two of whom required subsequent surgical repair. Three patients died, two in the early postoperative period, and one, 8 months after surgery from paraprosthetic regurgitation with hemolysis and heart failure. Antibiotics were given during and after surgery for as long as 6 weeks. In no case has recurrent sepsis been a problem.
Our experience indicates that open heart surgery, when necessitated by progressive congestive heart failure due to valve destruction, can be safely and effectively performed during or shortly after treatment of bacterial endocarditis.
The Pulmonary Vasculature in Complete Transposition of the Great Vessels, Judged from Lung Biopsies
Authors: WAGENVOORT C. A. , NAUTA J. , VAN DER SCHAAR P. J. , WEEDA H. W. H. , WAGENVOORT NOEKE 
Published: June 2012

Specimens of the lung taken for biopsy at operation on 80 patients with complete transposition of the great vessels were histologically studied in correlation with the clinical and hemodynamic data in these cases.
In a group of 31 cases of intact ventricular septum and patent foramen ovale, the media of the pulmonary arteries was generally thinner than normal, and to a lesser extent that of the pulmonary veins was also, while the lumina of the vessels were wide. This was especially observed in cases in which the hematocrit was high. Possibly, this phenomenon is based on dilatation of the arteries and is related to the increased total blood volume. Intimal fibrosis, when observed, was suggestive of organized thrombi.
In a group of 28 patients with ventricular septal defect and equal pressures in the left and right ventricles, there was generally marked medial hypertrophy and concentric intimal proliferation in the pulmonary arteries. In cases of pulmonic stenosis, on the other hand, the media of the pulmonary arteries was usually atrophic, while intimal fibrosis on the basis of thrombotic lesions was regularly present.
Renal Excretion of Sodium During Oral Water Administration in Patients with Systemic Hypertension
Authors: METZGER ROBERT A. , VAAMONDE LILIANA S. , VAAMONDE CARLOS A. , PAPPER SOLOMON 
Published: June 2012

The renal excretion of sodium and water was studied in 10 hypertensive subjects following an oral sustained 20 ml/kg water load. The study was performed under conditions controlled for sodium content of the diet, time of the day, and posture; the urine was collected by spontaneous voiding. The results were compared with those obtained from 10 normotensive subjects studied under similar conditions.
The increased urine flow following the water load in the hypertensive subjects was not accompanied by increased excretion of sodium, a pattern similar to the one observed in the normotensive subjects.

Comparing the group of hypertensive subjects with previously studied normotensives revealed the following additional information. The hypertensive subjects responded to water administration by increasing volume and C

H
H2
O

more rapidly than the normotensives; however, the maximal response was not significantly different. The fractional reabsorption of sodium was less in the hypertensive subjects despite a lower filtered load of sodium. This suggests a difference in the renal tubular handling of sodium between hypertensive and normotensive subjects.
Successful Surgical Interruption of the Bundle of Kent in a Patient with Wolff-Parkinson-White Syndrome
Authors: COBB FREDERICK R. , BLUMENSCHEIN SARAH D. , SEALY WILL C. , BOINEAU JOHN P. , WAGNER GALEN S. , WALLACE ANDREW G. 
Published: June 2012

Recurrent supraventricular tachycardia is a frequent complication in patients with the Wolff-Parkinson-White (WPW) syndrome. Our patient was unusual in that the arrhythmia was the predominant rhythm, and it was felt that the sustained tachycardia was responsible for signs and symptoms of congestive heart failure. The arrhythmia could not be controlled adequately with digitalis, quinidine, diphenylhydantoin, or propranolol. Atrial or ventricular pacing also failed to prevent recurrent episodes of tachycardia.
Physiological and pharmacological studies suggested that an anomalous pathway was responsible for the WPW abnormality and participated in a re-entrant circuit which sustained the episodes of tachycardia. Isopotential body surface mapping suggested anomalous ventricular excitation at the lateral aspect of the right atrioventricular groove. Epicardial mapping at the time of surgery was used to localize the earliest area of anomalous ventricular activation, and surgical transection of the atrioventricular junction at that point abolished the electrocardiographic features of WPW and the recurrent tachycardia. Five months after surgery neither the ECG features of WPW nor the tachycardia has recurred. The signs and symptoms of congestive heart failure have subsided, and the patient has returned to work.
Influence of Angiotensin on the Hemodynamic Response to Exercise in Normotensive Subjects
Authors: SANNERSTEDT RUNE , VARNAUSKAS ED 
Published: June 2012

The effect of exercise on the systemic hemodynamic response in 11 healthy men has been studied before and during an intravenous infusion of angiotensin sufficient to increase the resting mean arterial blood pressure an average of 29%.
On exercise in the angiotensin period there was a significantly smaller rise of the systolic pressure than on exercise in the control state, and the response of the diastolic pressure was changed from a moderate increase to a decrease on an average. The increase in mean arterial pressure on exercise was almost abolished, being 4.3 mm Hg during the infusion compared with 20.6 mm Hg before infusion. The rise in cardiac output on exercise was significantly smaller during the angiotensin period, while at the same time there were no significant changes in the behavior of the heart rate, stroke volume, or systemic vascular resistance.
The findings indicate that the vasoconstricting effects of angiotensin are largely overcome by the vasodilating effect of exercise in the working muscle groups, but the possibility of relatively increased vasoconstriction in the vascular bed supplying less vitally important tissues is pointed out.
Physiological Analysis of Middle-Aged and Old Former Athletes
Authors: SALTIN BENGT , GRIMBY GUNNAR 
Published: June 2012

Blood lipids, red cell volume, heart volume, dynamic spirometry, electrocardiograms made at rest and during exercise, and maximal oxygen uptake were determined in 29 former athletes 45 to 70 years old. The subjects had been very successful competitors in endurance events before the age of 30, but for at least 10 years preceding this study had been sedentary.
Maximal oxygen uptake averaged 40 ml/kg/min which is 20% higher than that of sedentary middle-aged men but 25% lower than that of still active athletes of the same ages. Vital capacity, forced expiratory volume, and maximal voluntary ventilation showed normal values. Heart volume was large in relation to maximal oxygen uptake and was of the same magnitude as in still active athletes. Red cell volume was also large in relation to maximal oxygen uptake, but normal in relation to the body weight. Cholesterol in serum averaged 260 mg/100 ml. Values for neutral fat averaged 1.6 mM, which was higher than that for still active athletes.
In the athletes still active, the frequency of S-T changes was as common as in unselected healthy old men but in the former athletes the frequency was reduced. This was also true for the frequency of right bundle-branch block, ST-junction elevation and high T waves.
Dysplasia of the Systemic and Pulmonary Arterial System with Tortuosity and Lengthening of the Arteries
Authors: BEUREN ALOIS J. , HORT WALDEMAR , KALBFLEISCH HEINRICH , MÜLLER HELMUTH , STOERMER JOACHIM 
Published: June 2012

This article describes the case of a boy, 1 year and 5 months old, with generalized tortuosity and lengthening of all major arteries, including the coronary arteries and the pulmonary artery. The early death of the patient was attributed to coronary insufficiency and multiple severe peripheral pulmonary stenoses.
The pathological changes were confined to the elastic arteries and the first part of the muscular arteries. The wall of the aorta was thickened and there was an increase of the elastic fibers. The same changes were present in the main pulmonary artery. In the large muscular arteries, the characteristic changes were thickening of the intima with hyperplasia of the elastic fibers and degenerative fragmentation of the internal elastic membrane. The walls of the coronary arteries were thickened and their lumina were narrow.
Temperature of the Great Toe as an Indication of the Severity of Shock
Authors: JOLY HENRI R. , WEIL MAX HARRY 
Published: June 2012

To establish whether changes in skin temperature would provide objective indication of the presence and severity of shock, hemodynamic and temperature measurements were obtained with the aid of a digital computer. Values obtained 3 hours after admission and 3 hours prior to discharge or death in 100 patients who presented with clinical signs of circulatory shock were analyzed. Temperature was measured with standard thermistor probes at five sites: the digital pad of the third finger, the large toe, the deltoid region of the arm, the lateral portion of the thigh, and the rectum.
A significant correlation was demonstrated between the cardiac output and temperature of the toe (r = 0.71). Correlations were increased to 0.73 when corrections were made for changes in ambient temperature. A stepwise regression analysis provided no significant improvement in the predictability of cardiac index when the values for temperatures of other skin sites were included. Discriminant function analysis showed that an early measurement of toe temperature correctly predicts patient outcome 67% of the time.