bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hemodynamic Findings Following Replacement of the Mitral Valve with the University of Cape Town Prosthesis
Authors: BECK W. , FERGUSSON D. J. G. , BARNARD C. N. , SCHRIRE V. 
Published: June 2012

Postoperative hemodynamic studies have been performed on 11 subjects following replacement of the mitral valve. In eight cases a comparison was made with the preoperative findings.
The great improvement in the functional capacity of most patients is reflected in the findings of this study, which indicate a small gradient at rest across the prosthesis and no mitral incompetence. The residual gradient was thought to be due mainly to inadequate orificial size, although delay in reaching the fully open position may also play a part.
In two subjects a severely elevated pulmonary vascular resistance fell markedly following the relief of left atrial hypertension.
Two patients failed to show sustained clinical and hemodynamic improvement. In one, mild aortic valve disease was present and severe systemic hypertension developed, resulting in death. The influence of these factors is discussed. In the other, the cause for the continuing heart failure with poor left ventricular contractility was undetermined.
The Effect of Exercise on Postural Changes in the Electrocardiogram
Authors: BELLET SAMUEL , ROMAN LAURIAN 
Published: June 2012

The electrocardiogram before, during, and after a double two-step exercise test was studied in the upright position in 1,026 subjects with no apparent heart disease and in 70 patients with angina. Postural changes were found much more frequently in subjects with angina (18.5 per cent) and in apparently normal subjects with positive exercise tests (10.7 per cent) than in normal subjects with negative exercise tests, in which postural changes were found in only 3.4 per cent. Probable causes for these findings are discussed.
The criterion for positivity in over 80 per cent of exercise tests, namely, an ischemic ST depression, is rarely seen as a postural change in normal subjects. On the other hand, isolated T-wave changes, which represent approximately 90 per cent of the postural changes of the repolarization period, are very rarely the sole criteria for a positive exercise test. Therefore, only a small area of possible confusion exists between postural changes and positive exercise tests. However, even in such cases, careful examination of the tracings can resolve these difficulties.
Studies of Cardiopulmonary Blood Volume
Authors: LEVINSON GILBERT E. , PACIFICO ALBERT D. , FRANK MARTIN J. 
Published: June 2012

The volume of blood in the heart and lungs can be measured, by the Stewart-Hamilton principle, as the product of cardiac output and the mean transit time from right atrium to the aortic root. Although previous investigators have estimated a variety of central blood volumes, measurements of the true cardiopulmonary blood volume in man have not previously been reported.

Eighty-one measurements of the total cardiopulmonary blood volume were obtained in 15 normal human subjects. At rest, total cardiopulmonary blood volume ranged from 301 to 546 ml/m
2
, with a mean of 422 ml/m
2
, and it represented 15% of estimated total blood volume. Cardiopulmonary blood volume was significantly larger in the male subjects than in the female. Reproducibility of measurements was good: the mean discrepancy between successive replications was 25 ml/m
2
and the mean coefficient of variation 3.7%. There was no correlation between cardiac output and cardiopulmonary blood volume but a significant correlation (r=0.79,
P
<0.0001) was evident between cardiopulmonary blood volume and stroke volume.

With elevation of the legs to the pedals of a bicycle ergometer, a small but statistically significant increase occurred in cardiopulmonary blood volume, but no significant changes occurred in cardiac output, heart rate, or stroke volume. With exercise, no further significant change in cardiopulmonary blood volume occurred, despite significant increases in output, rate, and stroke volume.
Analysis of cardiac output measurements, both at rest and during exercise, indicates that aortic root sampling is characterized by an appreciably higher reproducibility than that reported for peripheral arterial sampling.
Renal Circulation in Man Studied by Means of a Dye-Dilution Method
Authors: REUBI FRANÇOIS C. , GOSSWEILER NICOLAS , GUÜRTLER RENÉ 
Published: June 2012

A dye-dilution method of measuring renal hemodynamics in man has been described. The method requires catheterization of both the renal artery and the renal vein, a single injection of dye into the renal artery, and recording of the venous dilution curve by means of a cuvette densitometer.
The method was evaluated in 11 normal subjects, eight patients with acute anuric renal failure, and 13 patients with chronic renal disease. In 26 instances the PAH clearance and the PAH-extraction ratio were determined simultaneously. The dye-PAH flow ratio averaged 0.98 for the whole series. The limitations of the dye method have been discussed.
The dye method probably makes it possible to estimate the blood flow distribution within the human kidney. The available data indicate that cortical blood flow in the normal kidney ranges from 80 to 93% of the total flow, with a mean transit time of 5 to 10 sec. The calculated cortical vascular volume ranges from 52 to 78% of the total volume. The extracortical flow presumably represents medullary circulation with a mean transit time of 19 to 25 sec.
In anuric renal failure the total renal blood flow averaged 55% of normal and did not increase significantly during the subsequent polyuria. The shape of the dilution curves remained essentially normal in anuria and polyuria as well.
Vectorcardiographic Studies in Acquired Valvular Disease with Reference to the Diagnosis of Right Ventricular Hypertrophy
Authors: CUETO J. , TOSHIMA H. , ARMIJO G. , TUNA N. , LILLEHEI C. WALTON 
Published: June 2012

The orthogonal vectorcardiogram described by Schmitt and Simonson has been studied in 37 patients with "pure" mitral stenosis.
The diagnosis of right ventricular hypertrophy (RVH) could be established from changes in the magnitude, azimuth, and elevations of the initial, middle, and terminal forces, which could not be detected by the routine 12-lead electrocardiogram. This type of [see figure in the PDF file] recording has proved to be of great value in the diagnosis of right ventricular hypertrophy, particularly when the hypertrophy is of mild or moderate degree. Analysis of the instantaneous vectors has proved to be the single most important criterion in the electrocardiographic diagnosis of right ventricular hypertrophy.
Red Cell Survival in Patients with Mitral Valvular Disease and Mitral Valve Prostheses
Authors: BRODEUR MICHAEL T. H. , KOLER ROBERT D. , STARR ALBERT , GRISWOLD HERBERT E. 
Published: June 2012

Red cell survival times were measured in patients with mitral valvular disease, mitral ball-valve prostheses, and multiple valve prostheses. Red cell survival was shortened in patients with mitral valvular disease but not in patients who had insertion of a normally functioning mitral prosthesis or after mitral commissurotomy.
Mean red cell survival was also reduced in patients who had normal mitral prostheses associated with aortic valvular disease and in patients with a leak around the mitral prosthesis.
Mean red cell survival was the same in patients with multiple prostheses and in patients with a single aortic prosthesis. If a leak developed around the mitral prosthesis in patients with multiple prostheses, hemolytic anemia could develop. Renal excretion of iron and iron deficiency were demonstrated in two patients with traumatic hemolytic anemia. The urinary iron loss apparently exceeds the capacity for intestinal absorption, and parenteral iron would seem to be indicated for replacement.
Open Intracardiac Repair for Complete Transposition of the Great Arteries
Authors: HIGHTOWER BILLY M. , WEIDMAN WILLIAM H. , KIRKLIN JOHN W. 
Published: June 2012

Seventeen of 44 patients undergoing operation for complete correction of transposition of the great arteries survived operation and were dismissed to return home. Three late deaths followed. Mortality remains high among infants less than one year old and among patients of all ages who have severely elevated pulmonary vascular resistance.
Nine of the last 13 patients, in whom repair was accomplished by the Mustard technique, have survived. Late results in all surviving patients have generally been excellent.
Selective Cine Coronary Arteriography
Authors: PROUDFIT WILLIAM L. , SHIREY EARL K. , SONES F. MASON 
Published: June 2012

The clinical records of 1,000 patients who had adequate selective cine coronary arteriography were reviewed. The clinical diagnoses were made by a physician who had no knowledge of the arteriographic findings. Correlation of the clinical diagnoses with the arteriographic findings was made subsequently.
Symptomatic coronary disease was accompanied by arteriographic evidence of significant obstruction of major coronary arteries in most instances. A close correlation existed between the clinical diagnosis of angina pectoris without rest pain and significant arterial obstruction (95%). A similar correlation was found between QRS evidence of myocardial infarction and severe arterial obstruction (99%). The demonstrated arterial obstruction in patients who had angina pectoris almost always was severe and usually almost total or total in one or more major vessels. In myocardial infarction the demonstrated obstruction was always severe and generally almost total or total.
The correlation between clinical and arteriographic findings was moderately close in patients who had angina with symptoms at rest. The correlation between the arteriographic findings and less characteristic clinical syndromes (rest pain only, 79%, coronary failure, 78%, and especially atypical angina pectoris, 65%) was not so close. In congestive failure secondary to coronary disease, arterial obstruction was extensive unless ventricular aneurysm, mitral insufficiency, arrhythmia, arterial hypotension, or some other complication was present. Most patients thought to have noncoronary symptoms had no significant obstructive lesions.
In 37% of the entire group of patients, almost all of whom had been suspected of having coronary disease by some physicians, no significant arteriographic obstruction was demonstrated; in 27% the arteriograms were normal.
Diagnoses, based on appraisal of the clinical records without knowledge of the arteriographic findings, yielded 83% correlation with abnormal arteriographic findings in 700 patients thought to have coronary disease.
Carcinoid Heart Disease
Authors: AROESTY JULIAN M. , DEWEESE JAMES A. , HOFFMAN MARVIN J. , YU PAUL N. 
Published: June 2012

A patient with carcinoid syndrome with both tricuspid and pulmonic valvular lesions has been described. Successful repair of the valvular lesions was performed under cardiopulmonary bypass. The operation consisted of pulmonic valvotomy with the excision of a single pulmonic valve cusp, and replacement of the tricuspid valve by a Starr-Edwards prosthesis. Postoperatively, the patient noted marked improvement in symptomatology, and there was a concomitant improvement in serial hemodynamic studies.
The development of the signs of tricuspid regurgitation and pulmonic stenosis in patients with metastatic carcinoid tumor should alert the physician to the possible presence of carcinoid heart disease. If hemodynamic and angiocardiographic studies confirm the presence of significant valvular lesions, corrective cardiac surgery should be performed in selected patients.
Electrocardiographic Changes Reflecting Left Atrial Abnormality in Hypertension
Authors: TARAZI ROBERT C. , MILLER ANTHONY , FROHLICH EDWARD D. , DUSTAN HARRIET P. 
Published: June 2012

To separate the effects of hypertension and atherosclerosis on the left atrium, the electrocardiograms of 76 hypertensive patients and 76 normal control subjects, matched for age and sex, were studied. Four established criteria for left atrial abnormality were used. One or more positive criteria were satisfied in 45 of the 76 patients and 28 had two or more positive criteria. In contrast, only four of the 76 normal subjects had one abnormal criterion; none had more than one. In 37 patients selective coronary cinearteriography was performed and five of these with abnormal P waves had no arteriographic evidence of atherosclerosis. Eleven of 45 patients with left atrial abnormality had repeated episodes of atrial arrhythmias, whereas only one of the 31 patients with normal P waves had an atrial arrhythmia, demonstrating that repeated atrial arrhythmias are more frequent in patients with left atrial abnormality.
Left atrial abnormality was, therefore, a frequent finding in hypertension; it may occur even in the absence of cardiac enlargement and coronary arterial disease. It was, at times, the sole sign of cardiac abnormality in hypertension.
Orthostatic Hypotension as a Clue to Primary Systemic Amyloidosis
Authors: KYLE ROBERT A. , KOTTKE BRUCE A. , SCHIRGER ALEXANDER 
Published: June 2012

Data on 11 patients with orthostatic hypotension and primary systemic amyloidosis have been presented. Dizziness and light-headedness or syncope significantly hampered the involved patients. Three were incapacitated by orthostatic hypotension.
Diarrhea, nausea, vomiting, and loss of weight were common, and adrenal insufficiency was seriously considered in the differential diagnosis of six of the 11 patients. Abnormal sweating was found in all six in whom this test was done.
The drug 9-α-fluorohydrocortisone showed promise in symptomatic therapy of the condition. The possibility of primary systemic amyloidosis should be considered in the presence of orthostatic hypotension. Rectal biopsy and bone-marrow aspiration are recommended as initial biopsy procedures unless another organ suitable for biopsy is obviously involved.
The Vectorcardiogram in Complete Transposition of the Great Vessels
Authors: KHOURY GEORGE H. , SHAHER REDA M. , FOWLER RODNEY S. 
Published: June 2012

The Frank vectorcardiograms of 50 patients with complete transposition of the great vessels were analyzed, and the findings were correlated with the electrocardiogram and hemodynamics. The patients were divided into four groups according to the presence or absence of ventricular septal defect and left ventricular outflow tract obstruction. In group I, consisting of 20 patients with ventricular septal defect, the vector cardiograms showed evidence of combined ventricular hypertrophy in 80% of the cases, the scalar electrocardiogram, in 40%.
In group II, 13 patients with ventricular septal defect and left ventricular outflow tract obstruction, the vectorcardiogram was consistent with either right, combined, or left ventricular hypertrophy.
In groups III and IV, patients with intact ventricular septum with or without left ventricular outflow tract obstruction, the vectorcardiogram was consistent with right ventricular hypertrophy in the majority of cases.
The Vectorcardiogram in Cystic Fibrosis
Authors: LIEBMAN JEROME , DOERSHUK CARL F. , RAPP CLYDE , MATTHEWS LEROY 
Published: June 2012

One hundred and one children with cystic fibrosis had detailed studies of the vectorcardiograms and pulmonary function tests. The vectorcardiographic diagnoses were (1) right ventricular hypertrophy (14 patients), (2) right ventricular hypertrophy plus abnormally posterior vector (24 patients), (3) abnormally posterior vector (26 patients), (4) low voltage (nine patients), and (5) tracing within normal limits (35 patients).
Right ventricular hypertrophy correlated well with a decreased vital capacity. Abnormally posterior vector correlated well with increased residual volume and functional residual capacity. The presence of the abnormally posterior vector was demonstrated to be the major factor in the difficulty in interpreting right ventricular hypertrophy from the electrocardiogram, for a large terminal rightward vector was often too far posterior to be registered as a terminal R in the right chest leads.
The Frank system vectorcardiogram was demonstrated to be better able to detect right ventricular hypertrophy than was the cube system vectorcardiogram. This was particularly true in the presence of an abnormally posterior vector.
An abnormally leftward 0.01-second vector, if it is anterior, is frequently seen in right ventricular hypertrophy.
An Autopsy Study of Leg Vein Thrombosis
Authors: STEIN PAUL D. , EVANS HILARY 
Published: June 2012

An autopsy study of leg veins in unselected patients was performed in which postmortem venography, complete gross dissection, and microscopic examination were utilized in order to assess the incidence, location, origin, and mode of propagation of venous thrombi in the leg. The incidence of leg vein thrombosis is high; 13 of 27 patients studied (48%) had antemortem thrombi. Thrombosis in the veins of the thigh occurred often (eight patients), but thrombosis in the veins of the calf was even more frequent (12 patients). Thrombi large enough to cause significant pulmonary embolism were found in seven patients. Leg vein thrombi were found in five of the six patients in this study who had pulmonary embolism at autopsy. Initiation of thrombosis was noted in the veins of both the thighs and the calves. The valve pockets were a frequent site of origin of thrombi. Inflammation of the wall of the vein (phlebitis) secondary to thrombosis was found in one patient.
Postmortem venography is a useful and simple adjunct for the autopsy study of leg vein thrombosis. It is particularly reliable for the detection of thrombi in the thigh.
Muscular Subaortic Stenosis
Authors: WIGLE E. DOUGLAS , AUGER PIERRE , MARQUIS YVES 
Published: June 2012

Left ventricular ejection time was correlated with the intraventricular pressure gradient in 35 cases of muscular subaortic stenosis in which simultaneous aortic and left ventricular pressure recordings were available. Ejection times were corrected for heart rate by dividing them by the square root of the cycle length. There was a direct relation between the degree of prolongation of the ejection time and the magnitude of the pressure gradient whether the latter varied spontaneously or followed surgical or pharmacological intervention. The only exceptions occurred in three of nine cases during stimulation of the gradient with isoproterenol.
In contrast, when an intraventricular pressure difference resulted from catheter entrapment in left ventricular myocardium in patients with nonobstructive cardiomyopathy, there was an inverse relation between ejection time and pressure difference, whether the latter varied spontaneously or following pharmacological intervention.
These studies provide further evidence that (1) two types of intraventricular pressure difference may be encountered within the left ventricle of man, and (2) the pressure difference in muscular subaortic stenosis results from obstruction to the left ventricular outflow.
Raynaud's Disease in Children
Authors: GUNTHEROTH WARREN G. , MORGAN BEVERLY C. , HARBINSON JOHN A. , MULLINS GAY L. 
Published: June 2012

Six children with primary Raynaud's disease have been studied with plethysmography and multiple-site skin-temperature readings. All six were free of systemic disease. Each demonstrated the characteristic sequence of pallor, cyanosis, and rubor when subjected to generalized cold, but application of local cold produced only modest reduction in skin temperature and digital pulse. Only one child had a history of vasospastic symptoms associated with emotional stimuli, and she was the only one in whom an emotional challenge was able to produce Raynaud's phenomenon during the physiological studies. Tolazoline, in doses small enough to avoid generalized vasodilatation, was effective in substantially increasing flow to the affected digits.
The involvement of only one or two digits, next to completely uninvolved digits, is a conclusive argument for a primarily local sensitivity. However, the ability to precipitate vasospasm with generalized cold, versus local cold applications, and emotional stimuli indicates the importance of the nervous system in the manifestation of Raynaud's disease.
Surgical Correction of Absence of Proximal Segment of Left Pulmonary Artery
Authors: GREEN GEORGE E. , REPPERT EDMUND H. , COHLAN SIDNEY Q. , SPENCER FRANK C. 
Published: June 2012

In a 14-month-old patient who had been repeatedly hospitalized for recurrent pulmonary infections, cardiac angiography found "absence" of the left pulmonary artery, but thoracic aortography demonstrated that a rudimentary patent ductus filled a distal patent pulmonary artery. There was a coexistent vascular ring with a retroesophageal right subclavian artery.
At surgical exploration it was possible to mobilize the distal left pulmonary artery and perform a direct anastomosis between the left pulmonary artery and the main pulmonary artery. This is perhaps the first patient in whom such an operation has been performed. It is emphasized that the absence of a pulmonary artery on pulmonary angiography does not indicate that the entire pulmonary artery is absent. The presence of a patent and surgically reconstructable distal pulmonary artery can be determined only by aortography or possibly by surgical exploration.
Natural History of Congenital Heart Disease
Authors: HOFFMAN JULIEN I. E. 
Published: June 2012

It is difficult to make prognoses and decisions on therapy of individuals with congenital heart disease (CHD) and plan efficiently for medical services and training programs because studies on the incidence and relative frequency of different types of CHD at birth, mortality rates, times of death, and prevalence rates in children and adults are incomplete or unrepresentative. The present study assesses the merits of previous surveys and attempts to indicate the best information about these rates.
Specific attention has been directed to data on ventricular septal defect (VSD), with an estimated incidence of at least 20/10,000 live births; about 10% of these children died before 15 years of age. There should thus be about 18/10,000 surviving school children with VSD, yet the most intensive school surveys show only about half this number. This supports the suggestion that there is a high incidence (perhaps 50%) of spontaneous closure of VSD during childhood. Spontaneous closure may also occur frequently after childhood, but this conclusion needs to be confirmed by better surveys.