bluuebunny/crossref_metadata_2025_split huggingface dataset:
Operative Therapy for Femoral-Popliteal Arterial Occlusive Disease
Authors: KOUCHOUKOS NICHOLAS T. , LEVY JEROME F. , BALFOUR JOHN F. , BUTCHER HARVEY R. 
Published: June 2012

One hundred ninety-four patients underwent 222 operations for femoral-popliteal arterial occlusive disease between 1957 and 1965. The results of operative therapy employing synthetic bypass grafts, thromboendarterectomy, and autogenous saphenous veins were assessed by determining the accumulative patency rates for the three operative methods, the incidences of subsequent major amputations, and the degree of symptomatic relief (fig. 1, tables 9 and 10).
The 2-year accumulative patency rates for synthetic bypass grafts, thromboendarterectomy, and saphenous vein bypass grafts were 28%, 50%, and 63%, respectively (table 8). Subsequent major amputations were performed in 37%, 27%, and 12% of the extremities in the three groups. Improvement in symptoms occurred in 33%, 48%, and 73% of the patients in the respective groups.
When grouped according to severity of presenting symptoms and signs and the status of the arterial outflow by arteriography, patency rates were highest in the vein graft group and lowest in the synthetic graft groups. The patency rates after endarterectomy in those extremities with severe symptoms and poor arterial outflow tracts were similar to those of the synthetic graft group.
A Nonthrombogenic, Nonanticoagulant-Dependent Mitral Valve Prosthesis
Authors: PALMER TREVELYAN E. , LAUTSCH ELIZABETH V. , SANMARCO MIGUEL E. , DAVILA JULIO C. 
Published: June 2012

Thromboembolism stems from incompletely covered foreign body which is in physical continuity with tissue. Cardiac valve prostheses which remain partially exposed show, at the tissue-to-prosthesis junction, incomplete healing which is characterized by continuing granulation and proliferating immature unstable scar tissue, from which thrombosis originates and propagates.
The principle of complete encapsulation with healthy granulation tissue, maturation into stable fibrous tissue without inflammation, covered by a normal antithrombogenic endothelial surface, is a more logical approach than [see Figure in the PDF file] methods which attempt to prevent thrombosis by altering the character of the surface of the exposed foreign body or the blood coagulation mechanism. A valve is described which functions eminently satisfactorily as a replacement for the calf mitral valve.
Conservative Management of Tricuspid Regurgitation in Patients Undergoing Mitral Valve Replacement
Authors: BRAUNWALD NINA S. , ROSS JOHN , MORROW ANDREW G. 
Published: June 2012

Among 100 consecutive patients undergoing mitral valve replacement, 28 had clinically and hemodynamically significant tricuspid regurgitation without tricuspid stenosis. In 21 patients the mitral valve was regurgitant, and in eight it was stenotic. The characteristic murmur of tricuspid regurgitation was present in 27 patients; 25 had abnormal venous distention, 14 peripheral edema, and seven ascites; and in 27 the liver was enlarged more than 4 cm below the costal margin. The mean right atrial pressure was abnormally high in every patient (average 11 mm Hg), and 25 had severe pulmonary hypertension (average systolic pressure 75 mm Hg). At the time of mitral replacement, 25 patients had no operative procedure on the tricuspid valve, and three had a tricuspid annuloplasty. Four patients died, a mortality rate (14%) not different from that in the patients without tricuspid regurgitation.
Twenty-four patients were reassessed at postoperative intervals of one to four years (average 30 months). All evidenced symptomatic improvement; 16 observed no dietary restriction of sodium, six ate regular diets without added salt, and only two limited sodium intake more stringently. Postoperatively, mean right atrial pressures averaged 5 mm Hg and systolic pulmonary arterial pressures 39 mm Hg.
In many patients with advanced mitral valve disease, associated tricuspid regurgitation is of a functional nature and secondary to right ventricular hypertension and dilatation of the tricuspid annulus. The present results indicate that in such patients tricuspid regurgitation will improve or disappear after mitral replacement and that tricuspid valve replacement is seldom necessary.
Cardioversion after Mitral Valve Operations
Authors: KAHN DONALD R. , KIRSH MARVIN M. , FERGUSON PAULINE W. , SLOAN HERBERT 
Published: June 2012

When atrial fibrillation is converted to normal sinus rhythm following the surgical repair of mitral valve disease, the normal pattern is more likely to persist if the preoperative diagnosis is mitral stenosis, atrial fibrillation has been established for less than 3 years, and results of the operation are excellent. To determine the specific reasons for recurrence of fibrillation, however, and to devise ways of preventing these recurrences will require further investigation of both pathogenic mechanism and therapeutic agents.
In 55 patients with mitral valve disease and atrial fibrillation operated upon at The University of Michigan Medical Center from 1963 to 1966, normal sinus rhythm was established after operation in 43 but maintained in only 20. Most recurrences of atrial fibrillation appeared during the first 3 months after the heart operation. The time lapse between operation and cardioversion did not affect the conversion rate or maintenance. Cardioversion was more often successful after valvuloplasty than after valve replacement, but the maintenance rate was the same.
Studies of Cardiopulmonary Blood Volume
Authors: LEVINSON GILBERT E. , FRANK MARTIN J. , NADIMI MANOUCHEHR , BRAUNSTEIN MILTON 
Published: June 2012

The measurement of ventricular end-diastolic volume from washout of an indicator requiring blood sampling was studied in a heart model and in dogs and applied to the left ventricle in 34 human subjects. The model, under the ideal conditions of constant ejection fraction, uniform cycle length, and complete or nearly complete mixing, demonstrated that dye dilution accurately measures chamber volumes if the distorting effects of catheter sampling are obviated by clearance of the sampling system at least once per two cardiac cycles. The studies in dogs and in human beings demonstrated that the required sampling conditions are achievable.

In 11 normal human subjects, left ventricular end-diastolic volume ranged from 72 to 99 with a mean of 82 ± 12 ml/m,
2
end-systolic volume, from 22 to 60 with a mean of 37 ± 11 ml/m,
2
and ejection fraction, from 0.39 to 0.71 with a mean of 0.55 ± 0.08. These measurements are in substantial agreement with results by radiocardiography and thermal dilution and are systematically, but only slightly, higher than results by quantitative angiocardiography.

In six considerably older patients with chronic pulmonary disease, cardiac output was normal for the age group but ejection from a ventricle of normal size was reduced. In 12 subjects with pure mitral stenosis and in five with atrial septal defect, end-diastolic volume and ejection fraction were significantly reduced.
End-diastolic volume correlated with stroke volume in all groups and in the series as a whole, but a correlation between end-diastolic volume and cardiac output was demonstrated only in the patients with mitral stenosis or atrial septal defect. This suggests that chronic restriction to ventricular filling results in decreased end-diastolic volume. The absence of a significant correlation between end-diastolic volume and end-diastolic pressure indicates that variation in ventricular compliance precludes reliance on end-diastolic pressure as a valid index of end-diastolic fiber length.
Relation of Heart Rate and Systolic Blood Pressure to the Onset of Pain in Angina Pectoris
Authors: ROBINSON BRIAN F. 
Published: June 2012

Arterial pressure was recorded directly and continuously in 15 patients with angina pectoris while pain was repeatedly induced by exercise of various types and severity. In every case, the precipitation of angina could be consistently related to the level reached by the product of heart rate and systolic blood pressure (corrected when necessary for changes in ejection time). This relationship persisted even when there were large variations in the type, intensity, and duration of the exercise and was also maintained in a patient in whom spontaneous and emotional episodes of pain were observed. A substantial improvement in exercise tolerance occurred in one patient and this was completely accounted for by a reduction in the circulatory response to exercise.
It was concluded that the precipitation of angina is normally the result of a rise in the work of the myocardium to a critical level which is essentially fixed in each patient. The varying ease with which pain is provoked on different occasions can usually be explained by variations in circulatory response to the precipitating stress.
Muscular Subaortic Stenosis
Authors: WIGLE E. DOUGLAS , MARQUIS YVES , AUGER PIERRE 
Published: June 2012

Two types of intraventricular pressure difference within the left ventricle of man are described. The first type was encountered in eight consecutive patients with muscular subaortic stenosis in whom the outflow tract pressure distal to the stenosis was low and equal to the aortic systolic pressure, whereas all ventricular pressures proximal to the stenosis, including that just inside the mitral valve (the initial inflow tract pressure) were high. The second type was encountered in five of 10 patients with nonobstructive cardiomyopathy when a cardiac catheter was advanced to the left ventricular wall where it became entrapped or imbedded in cardiac muscle in systole and recorded a high ventricular pressure that was believed to reflect subendocardial intramyocardial tissue pressure. In this second type of intraventricular pressure difference, the initial inflow tract pressure, as well as all truly intracavitary pressures, were low and equal to the aortic systolic pressure.
By defining two types of intraventricular pressure difference, the recent controversy as to the nature of such pressure differences in man may be resolved, and the obstructive nature of muscular subaortic stenosis reaffirmed.
Protection from Digitalis Toxicity with the Prophylactic Use of Diphenylhydantoin Sodium An Arrhythmic-Inotropic Dissociation
Authors: HELFANT RICHARD H. , SCHERLAG BENJAMIN J. , DAMATO ANTHONY N. 
Published: June 2012

Diphenylhydantoin sodium (Dilantin) given prophylactically increased the dose of digitalis necessary to produce toxicity by 72 to 224%. At constant heart rates, pretreatment with diphenylhydantoin sodium did not alter the elevation of rate of rise of left ventricular pressure produced by the glycoside.
Two implications have been drawn from these findings. First, the inotropic and arrhythmic actions of digitalis can be dissociated, since diphenylhydantoin sodium seems specifically to counteract the electrophysiological actions of the glycoside. Second, pretreatment with diphenylhydantoin sodium significantly widened the "toxic-therapeutic" ratio of digitalis. This, therefore, may have important clinical applications.
Antihypertensive Properties of Furosemide
Authors: DAVIDOV MICHAEL , KAKAVIATOS NIKOS , FINNERTY FRANK A. 
Published: June 2012

The antihypertensive properties of single doses of furosemide were evaluated in 113 patients. Doses over 120 mg consistently produced a fall in arterial pressure whereas smaller doses did not. Thus 20 of 22 patients (90%) who received more than 120 mg had a 26 ± 6% average reduction in mean arterial pressure. The hypotensive action began in 30 to 45 minutes, the nadir of the decrease occurred between 2 and 2½ hours, and the hypotension usually lasted 10 to 12 hours. Repeated weekly doses of furosemide over a 2-month period in six patients were not associated with development of drug resistance. The antihypertensive properties of doses of furosemide of more than 120 mg seemed to be of about the same potency as ethacrynic acid. The antihypertensive effect of high doses of furosemide did not seem to be related to the diuretic effect or to the decrease in plasma volume.
These studies have demonstrated that doses of furosemide of more than 120 mg consistently decreased arterial pressure. The usefulness of this agent in the long-term management of hypertension remains to be determined.
SPECIAL ARTICLE
Authors: VON DER GROEBEN J. 
Published: June 2012

The diagnostic classification of the ECG waveform can be performed either by visual inspection of the electrocardiogram or by a set of mathematical-statistical decision rules programmed into a computer. It can be demonstrated that if the visual inspection technique is used, the 12-lead ECG will be superior to three scalar orthogonal vectorcardiographic leads. Plane projection vector loops lack accurate data display. If computer techniques are used, suitable decision regions of the instantaneous heart vector will provide accurate decision rules on a three-lead system. Neither the 12-lead system nor the three-orthogonal lead system makes use of all the information available on the body surface. A detailed electrical torso mapping would be required if this information proves to be of diagnostic significance.
Misclassification in electrocardiographic diagnosis may be due to (1) failure of electrical events to reflect hemodynamic, anatomic, or biochemical changes; (2) loss of information between the cardiac generator and the body surface; (3) inadequate data display; (4) inadequate mathematical-statistical decision regions; and (5) insufficient number of teaching samples or inadequate independent evidence.
Exercise and Intermittent Claudication
Authors: SKINNER JAMES S. , STRANDNESS D. EUGENE 
Published: June 2012

Five men with arteriosclerosis obliterans (ASO) underwent a 3 to 8-month physical training program. The systolic pressure at the ankle (AP) before and after exercise, maximal walking time (MWT), and time of onset of claudication pain (CPT) were recorded on 4 different days. After training, these measurements were repeated on 3 different days. In addition, each subject was retested at his initial MWT.
There were significant increases in resting AP levels of three subjects, in CPT and MWT of all five subjects and in the postexercise AP levels of all five subjects. Pain diminished or disappeared for varying periods of time while four of the subjects were walking. These data signify that there was a significant increase in collateral circulation at rest, during or after exercise, or both, improving the blood supply to the obstructed leg.
Long-Term Results of Endarterectomy of the Internal Carotid Artery for Cerebral Ischemia and Infarction
Authors: HEYMAN ALBERT , YOUNG W. GLENN , BROWN IVAN W. , GRIMSON KEITH S. 
Published: June 2012

The immediate and long-term results of carotid endarterectomy for treatment of acute cerebral ischemia or infarction were studied in 95 patients who were observed for an average period of 40 months after the surgical procedure. The operation resulted in death for 12 patients and worsening of the neurological deficit in six others. During the follow-up period, there were 22 additional deaths, most of which were caused by myocardial infarction or other complications of systemic atherosclerotic vascular disease.
The significant factors adversely affecting the prognosis of these patients consisted of severe electrocardiographic abnormalities, the presence of bilateral carotid occlusive lesions, cerebral infarction prior to endarterectomy, and the age of the patient.
Following endarterectomy only five patients were observed to have recurrent attacks of transient cerebral ischemia which were few in number and stopped spontaneously. Recurrent cerebral infarction developed in only seven patients, six of whom had unsuccessful or incomplete removal of the carotid occlusive lesions. Although this low incidence of recurrent ischemia and infarction seems to be evidence for the therapeutic value of carotid endarterectomy, further observations on a comparable group of patients treated nonsurgically are needed to support this conclusion.
Influence of Hypertension on the Hemodynamic Response to Exercise
Authors: AMERY ANTOON , JULIUS STEVO , WHITLOCK LEIGH S. , CONWAY JAMES 
Published: June 2012

Sixty-one asymptomatic hypertensive patients from 19 to 68 years of age were subjected to a progressive exercise test on a cycle ergometer. A decline in maximal oxygen consumption and cardiac output and an increase in systolic blood pressure were observed with age. These findings were similar to those observed in normal subjects. In the middle-aged (35 to 49 years) and older subjects (50 to 60 years), the systolic pressure showed a greater increase with exercise than in normals of their age, but this did not apply to subjects aged 19 to 34 years. The cardiac response to exercise was normal at rest and at all levels of exercise in the middle-aged group, but the oldest group showed a reduced maximum cardiac output. In the youngest age group, cardiac output was normal at rest but fell below normal at all levels of exercise.
Maximal voluntary oxygen consumption and cardiac output were significantly reduced with increasing severity of hypertension.
The Coagulant and Thrombogenic Properties of Human Atheroma
Authors: LYFORD CHARLES L. , CONNOR WILLIAM E. , HOAK JOHN C. , WARNER EMORY D. 
Published: June 2012

Suspensions of gruel from severely atherosclerotic human aortas and coronary arteries were tested in several coagulation systems. The atheromatous material shortened the clotting time of normal whole blood and plasma and accelerated thrombus formation time in the Chandler apparatus. Normal human platelets in platelet-rich plasma were aggregated by the atheromatous gruel. Aggregation did not occur when the gruel was added to platelet-rich plasma from a patient with a severe factor XII (Hageman) deficiency. The intravenous injection of atheromatous plaque suspensions into rats caused thrombocytopenia, shortening of the whole blood clotting time, and thrombosis.
Coagulation of blood from patients with classical hemophilia, with Hageman factor deficiency, and with coumarin-induced anticoagulant effect was accelerated by the addition of the atheromatous gruel. Blood from patients given heparin, however, largely retained its anticoagulant activity.
Atheromatous material from both aortic and coronary arteries behaved similarly in the systems tested. The coagulant and platelet clumping properties of atheromatous plaques may be related to their content of fatty acids, phospholipids, collagen, or thromboplastin.
Computer Search for Electrocardiographic Lead Directions to Optimize Diagnostic Differentiation
Authors: BATCHLOR CHARLES D. , BERSON ALAN S. , NAVAL I. ALZONA , PIPBERGER HUBERT V. 
Published: June 2012

A computer was programmed to search for electrocardiographic lead directions, yielding optimal separations between records obtained from 500 normal subjects and 422 patients believed to have either left ventricular hypertrophy (LVH) or right ventricular hypertrophy (RVH). The majority of the patients with RVH (86%) exhibited chronic pulmonary disease with severe pulmonary insufficiency where development of chronic cor pulmonale was assumed. Autopsy confirmation of RVH or LVH was obtained in 38 cases. The diagnoses in the remainder were based on history and physical findings.
Resolved leads derived from a corrected orthogonal system were tested for discrimination of the three groups. The number of false-positive and false-negative classifications was kept approximately equal. To simplify record analysis, the number of QRS measurements necessary for interpretation was limited to a single one.
The optimal lead direction to separate normal records from those obtained in patients with LVH had an azimuth angle of 306° and an elevation angle of –58°. The lead for separation of cases of RVH was almost identical with horizontal lead X. Comparison between results obtained with optimized leads and 12-lead records showed approximately equal performance for LVH when sensitivity and specificity were kept the same. These results were based on up to eight measurements from 12 leads as compared to one measurement in a single lead.
The diagnostic performance of optimized leads exceeded that of the 12-lead electrocardiogram when a set of the most commonly used criteria for LVH and RVH recognition was used.
A simple analog device for obtaining optimal leads was designed which can be attached to conventional single-channel electrocardiographs.
The feasibility of directional lead optimization by orthogonal lead resolution could be demonstrated with concomitant simplification of record analysis and greater ease in record taking.
Radiological Aspects of Heart Muscle Disease in Nigerian Adults
Authors: COCKSHOTT W. PETER , THORPE G. J. , IKEME A. C. 
Published: June 2012

A congestive cardiomyopathy, known locally as heart muscle disease, accounts for 32% of the cases of cardiovascular disease seen at University College Hospital, Ibadan, Nigeria.
Following a brief outline of the clinical picture and necropsy findings, the radiological features of the disease are described. Thirty-four cases were studied, and angiography was performed in 13. In the acute stage of the disease there was a generalized, globular, cardiac enlargement, and cardiac movements, especially of the left border of the heart, were reduced. Pulmonary venous congestion was invariably present and pleural effusions occurred frequently. Ventricular angiography demonstrated an enlarged chamber with little change in size and shape throughout the cardiac cycle, and persistence of contrast. Mitral incompetence was present in some cases. The value of angiography in differential diagnosis in emphasized.
Thoracic Duct-to-Pulmonary Vein Shunt in the Treatment of Experimental Right Heart Failure
Authors: COLE WILLIAM R. , WITTE MARLYS HEARST , KASH STEPHEN L. , RODGER MALCOLM , BLEISCH VIRGIL R. , MUELHEIMS GERHARD H. 
Published: June 2012

Elevated venous pressure in right heart failure leads not only to an increase in lymph formation but also to progressive resistance in the neck to the return of lymph to the circulation via the thoracic duct. Sequestration of fluid behind the failing heart tends to protect the circulation but at the same time leads to the clinical manifestations of heart failure.
The present study was performed on 40 dogs with combined tricuspid insufficiency and pulmonary stenosis. Thoracic duct lymph flow was greatly increased. Pressure was considerably greater in the systemic veins than in the pulmonary vein beyond the right heart obstruction. Lymph flow was substantially enhanced when the thoracic duct was connected to the lower pressure pulmonary veins. Furthermore, direct anastomosis of the thoracic duct to the pulmonary vein resulted in fall in systemic venous pressure, increase in renal excretion of salt and water, and reduction in ascites. These results indicate that alterations in the flow of thoracic duct lymph have important bearing on the manifestations and treatment of right heart failure.