bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surgical Treatment of Muscular Subaortic Stenosis
Authors: COOLEY DENTON A. , BLOODWELL ROBERT D. , HALLMAN GRADY L. , LASORTE ANTONIO F. , LEACHMAN ROBERT D. , CHAPMAN DON W. 
Published: June 2012

The results of surgical treatment of 26 patients with muscular subaortic stenosis are presented. Left ventricular septectomy was performed in 16 patients, and septal myocardiectomy via a right ventriculotomy was employed in the last ten patients. There were five hospital deaths among these patients, yielding a mortality rate of 19%.
Hemodynamic studies after operation in six patients showed relief of functional left ventricular outflow obstruction in all but one patient. This patient subsequently underwent successful right ventricular septectomy.
Recently we have employed a right ventriculotomy for excision of septal myocardium during digital exploration of the left ventricular outflow tract. Freedom from serious complications and effectiveness in relieving the subaortic stenosis recommend this technique for patients with obstructive cardiomyopathy.
Results of Operation for Atrial Septal Defect in Patients Forty-five Years of Age and Older
Authors: DAICOFF GEORGE R. , BRANDENBURG ROBERT O. , KIRKLIN JOHN W. 
Published: June 2012

1. The results of closure of atrial septal defects in 155 patients over 45 years of age have been reviewed.
2. The over-all operative mortality rate was 6.5%; the operative mortality rate in the last 48 patients was 2.1%.
3. The late results of operation were considered excellent in 83% and good in 13% of the patients.
4. Long-term follow-up studies suggest that patients have significantly longer survival with closure of their defects.
5. It is concluded that operation for atrial septal defect in the older patient may be done at a low risk with an excellent prospect of a good, long-term result in almost all cases.
Early Clinical Experience with Homotransplantation of the Aortic Valve
Authors: NELSON RONALD J. , MOHRI HITOSHI , WINTERSCHEID LOREN C. , DILLARD DAVID H. , MERENDINO K. ALVIN 
Published: June 2012

Twenty-five patients with predominant aortic valvular disease have had replacement with a homograft aortic valve inserted after the fashion of Barratt-Boyes. Recently used valves have been stored at -80 C, allowing prolonged storage and rapid reconstitution. There were five early deaths (20%), none of which was directly attributable to the choice of valve. Of three late deaths (12%) in up to 18 months follow-up, two were found to be due to complications of the valve resulting in aortic regurgitation-one secondary to a peripheral leak, the other to a fungal endocarditis.
All 17 survivors are greatly improved. All 11 patients who have survived over four months have returned to their former occupations. Five (29%) have no murmurs and 12 (71%) have no diastolic murmur. The five that have diastolic murmurs all show evidence of improvement. Tailoring the recipient annulus to fit the donor valve by means of "V" excision of the noncoronary sinus has been very important in minimizing the problem of valvular insufficiency.
Recatheterization at one year has revealed no systolic gradient in four patients. Aortic regurgitation was minimal in one patient. There has been no thromboembolism, although anticoagulants are not used. These promising early results support continued use and evaluation of the homograft aortic valve.
Factors Affecting Thromboembolism Associated with Prosthetic Heart Valves
Authors: DUVOISIN GEORGE E. , BRANDENBURG ROBERT O. , MCGOON DWIGHT C. 
Published: June 2012

The incidence of thromboembolism after insertion of prosthetic cardiac valves is related to the type of prosthesis and in the cases reviewed here was highest for the ball-valve prosthesis.
The risk of thromboembolism was studied by constructing actuarial curves showing the proportion of patients with embolism at increasing time intervals postoperatively. Such curves for the patients studied suggest that the risk of thromboembolism diminishes with time, particularly by the third postoperative year. The risk was remarkably similar for patients having aortic, mitral, and multiplevalve replacements, being 15% for the first 6 postoperative months, another 8% for the next 6 months, and another 20% for the next 2 years.
Emboli lodged in cerebral, coronary, renal, and other sites in these patients in diminishing frequency. The risk of fatality averaged 15%. None of the nonfatal embolisms resulted in significant continuing disability, save for 7% of the cerebral embolisms.
A beneficial effect of anticoagulation was demonstrated for patients having replacement of the aortic valve with a ball-valve prosthesis, particularly when this treatment was carefully controlled. In the latter group, the risk of thromboembolism was less than 5% 2 years postoperatively.
The Effect of Atrial Contraction on Left Ventricular Performance in Valvular Aortic Stenosis
Authors: KROETZ FRANK W. , LEONARD JAMES J. , SHAVER JAMES A. , LEON DONALD F. , LANCASTER JOHN F. , BEAMER VIRGINIA L. 
Published: June 2012

The instantaneous response of the left ventricle to loss or recovery of effective atrial contraction was studied in 12 patients with valvular aortic stenosis by producing A-V dissociation by electrical pacing of the ventricles so that some ventricular contractions were preceded by an effective atrial contraction while others were not. A conventional hydraulic formula relating size of the aortic valve orifice, pressure gradient, and flow was used to estimate beat to beat stroke volume. A properly timed atrial contraction augmented left ventricular performance in all patients, increasing stroke volume index from 14 to 55% (mean, 27%) and stroke work from 17 to 85% (mean, 45%).
The contribution of atrial contraction to integrated cardiac performance was studied in six of the same patients by comparing cardiac performance with right atrial pacing and right ventricular pacing. With right atrial pacing, each ventricular contraction was preceded by an atrial contraction, while with right ventricular pacing many ventricular contractions were not preceded by atrial contraction. Right atrial pacing increased cardiac index in four of six patients: The mean increase for the total group was 13% and the mean increase in left ventricular minute work index was 17%.
Although atrial contraction was capable of augmenting left ventricular performance in all patients studied, loss or recovery of effective atrial systole did not always alter integrated cardiac performance. Factors influencing atrial contribution remain poorly understood. Atrial contraction does not appear to have an unusual effect on the performance of the hypertrophied left ventricle.
Exercise and Intermittent Claudication
Authors: SKINNER JAMES S. , STRANDNESS D. EUGENE 
Published: June 2012

Four men with arteriosclerosis obliterans (ASO) were exercised on a treadmill on 4 different days to determine their maximal walking time (MWT) and the point at which their claudication pain (CPT) began. Each subject was exercised at 60%, 75%, and 90% of his MWT to determine the effect of work intensity on the systolic blood pressure at the ankle (AP). To measure the effect of exercise repeated on the same day, each subject walked five times each day on 4 different days at each of the three workloads. After each subject completed the required number of walks, his MWT was again measured on 4 separate days (one subject was retested only once) to determine whether it had changed.
In every case the greatest reduction in AP occurred after the initial maximal walk but the submaximal intensities caused different responses in the different subjects. With repetition of exercise each subject displayed a progressive increase in either the AP level taken 2 minutes postexercise or the rate of recovery of AP to the pre-exercise level. There were significant increases in MWT, in CPT, and in the resting and postexercise AP levels in some of these subjects. This was most probably due to increased collateral circulation before, during, and after exercise.
Diffuse Tortuosity and Lengthening of the Arteries
Authors: ERTUGRUL ALI 
Published: June 2012

This article describes the case of a 10-year-old girl with generalized tortuosity and lengthening of all her major arteries-the carotid arteries, the aorta from the arcus to the bifurcation, and the iliac, femoral, splenic, hepatic, renal, and intercostal arteries. The condition appears to be a new entity. Pertinent abnormalities were as follows: gross pulsation of the arteries in the neck, telangiectasis of both cheeks, high palate, tortuosity of all the arteries, aortic valvular insufficiency, 1+ to 2+ capillary fragility on tourniquet test (lacet), 1+ Wassermann reaction, 4+ cephalin flocculation, and histological fragmentation of the internal elastic membrane of the arteries.
Syphilis, arteriosclerosis, hypertension, mucopolysaccharidosis, and defects of amino acid metabolism were ruled out and the author concludes that the condition was most probably caused by a congenital defect of the elastic tissues of the arterial system.
Vascular Lesions in Infants with Congenital Rubella
Authors: ESTERLY JOHN R. , OPPENHEIMER ELLA H. 
Published: June 2012

Vascular lesions were reviewed in 13 autopsied infants with congenital defects of maternal rubella. The characteristic finding was intimal fibromuscular proliferation. The internal elastic lamella and media were almost always unchanged, even in the presence of a greatly thickened intima. These arterial changes appeared to be unlike other vascular lesions described in infancy.
Severe and extensive lesions were found in four infants, and lesser changes in another five. The lesions in the pulmonary artery were probably related to clinically diagnosed peripheral pulmonary artery stenosis. Ostial stenosis of a renal artery was found in an infant with documented systemic hypertension.
Permanent Ventricular Pacemakers
Authors: MORRIS JAMES J. , WHALEN ROBERT E. , MCINTOSH HENRY D. , THOMPSON HOWARD K. , BROWN IVAN W. , YOUNG W. GLENN 
Published: June 2012

In the series of 86 patients with the Stokes-Adams syndrome or with symptomatic bradycardia managed with permanently implanted ventricular pacemakers reported on, 35 patients had primary implantation of epicardial leads at thoracotomy and 51 had transvenous endocardial electrodes passed via the jugular venous system for permanent ventricular pacing. The transvenous method of permanent pacemaker implantation appears to be easier to apply with less serious complications and provides the same overall mortality as the transthoracic approach. However, pacemaker failure, both permanent and temporary, is more likely to occur with the transvenous approach.
A series of unique complications and findings noted in the transvenous group were thought to be related to the permanent pacing electrode catheter. These included myothought cardial perforation, pericardial friction rubs, intermittent ventricular pacing, and diaphragmatic stimulation.
The experience suggests that it is reasonable to employ a transvenous pacemaker initially, recognizing that replacement with a transthoracic pacemaker will be necessary in approximately 16% of the patients and remanipulation of the electrode catheter will be needed in another 13%. Therefore, to undertake transvenous permanent implantation of a pacemaker, one must also be prepared to employ the transthoracic approach in a small but significant number of patients.
The Role of Premature Beats in the Initiation and the Termination of Supraventricular Tachycardia in the Wolff-Parkinson-White Syndrome
Authors: DURRER D. , SCHOO L. , SCHUILENBURG R. M. , WELLENS H. J. J. 
Published: June 2012

In four patients with WPW syndrome atrial and ventricular premature beats were induced and the changes in form of the ventricular and atrial complexes were studied. Results indicate that, depending upon the timing of the premature atrial beat and the state of refractoriness of the His and Kent bundles, excitation of the ventricles occurs predominantly through the atrioventricular nodal system, predominantly through the Kent bundle or exclusively through one or both conduction systems. With short delays conduction through the Kent bundle may be blocked and only normal excitation of the ventricles occurs. In one patient with a history of attacks of tachycardia these normal QRS complexes were followed by retrograde activation of the atria by the Kent bundle, and attacks of supraventricular tachycardia of shorter or larger duration occurred. They stopped spontaneously, sometimes by delay or block, either of retrograde Kent conduction or of antegrade A-V nodal conduction, making it possible for the sinus node to capture the ventricles. They also could be terminated by induced atrial premature beats.
In two patients tachycardias could be induced by appropriately timed ventricular premature beats during regular driving of the right ventricle. In one of these patients a circus movement, involving the Kent bundle, is probably present. By appropriate stimulation of the atria or ventricles during an attack of supraventricular tachycardia in this patient, one cycle length could be shortened without changing those of the following beats. These results suggest that a circus movement involving the atria, the normal atrioventricular conduction system and the Kent bundle is present. In the other patient, not fulfilling the WPW criteria, ventricular or atrial premature beats did not interfere with the basic rhythm of the tachycardia. Two hypotheses for this tachycardia are given: nodal tachycardia caused by rapid firing of the A-V node or a nodal tachycardia caused by a reciprocal mechanism in the A-V junction. The attacks could be blocked too by appropriately timed atrial and ventricular premature beats. No ventricular type of tachycardia could be demonstrated.
Experimental Production of Aberrant Ventricular Conduction in Man
Authors: COHEN STAFFORD I. , LAU SUN H. , HAFT JACOB I. , DAMATO ANTHONY N. 
Published: June 2012

Aberrant ventricular conduction (AbC) was produced in 17 of 18 subjects, including six normal persons, by the introduction of electric stimuli via a transvenous catheter situated in the right atrium.
Analysis of electrophysiological determinants indicated that AbC was favored by a long cycle preceding the short cycle which terminated in the aberrant complex, a short R to stimulus coupling interval, and fast atrioventricular conduction time.
Electrocardiographic analysis of AbC revealed that all patients had right bundle-branch block (RBBB). In addition, incomplete right bundle-branch block was present in eight patients and was transformed to RBBB in all cases by shortening the coupling interval. Ten patients had slight but distinct variations of their RBBB pattern. There were two instances each of left bundle-branch block and intraventricular conduction disturbance. Hence, any patient may have the potential to produce a variety of AbC patterns. AbC was produced in six normal subjects and must be considered a physiological event which does not require covert pathology of the specialized conduction system.
Effect of Hyperventilation on Precordial T Waves of Children and Adolescents
Authors: THOMSEN J. H. , WASSERBURGER R. H. 
Published: June 2012

Following the taking of 12-lead routine electrocardiograms, three precordial leads were recorded before, during, and after 10 to 15 seconds of voluntary hyperventilation in 296 students, ranging in age from 8 to 17 years.
Fifteen per cent of the total group, comprising 212 Caucasians and 84 Negroes, inverted one or more previously upright precordial T waves following hyperventilation. The incidence of T-wave inversion in children 12 years of age and under was nearly four times greater in Caucasians than in Negroes. There was no significant difference when the older Negro and Caucasian students were similarly compared. Sinus tachycardia, T-wave flattening, and "tucking," short of frank inversion, as well as junctional depression of the ST segment, were commonly seen following hyperventilation.
The similarity of the hyperventilation-induced T-wave inversion in children to those previously documented in adults is noted, and the clinical implication of this study requires continued cognizance of the occurrence of "nonpathological" T-wave inversion in adults, so as to avoid iatrogenic heart disease.
Chromosomal Abnormalities and Congenital Heart Disease
Authors: EMERIT INGRID , DE GROUCHY J. , VERNANT P. , CORONE P. 
Published: June 2012

In this study the authors attempted to determine the frequency of the classical chromosomal syndromes as a cause of congenital heart disease and sought other cytogenetic abnormalities in patients with congenital heart disease, selected either for the presence of extracardiac abnormalities or the existence of congenital heart disease in other members of the family.
Of the 275 patients whose karyotypes were determined, 119 had a known syndrome. A chromosomal aberration, such as trisomy 21, a sex chromosomal aneuploidy, such as XO, XXY, XYY, XXX, or a more complex mosaic was found in 39. Among the other patients of this group, only a patient with Fanconi's anemia showed abnormalities of the karyotype (numerous chromatid and isochromatid breaks).
Among 100 other patients with unclassifiable associated malformations, 10 had abnormal karyotypes. The following abnormalities were noted: complex structural rearrangements, minute chromosome fragments, variations in size of the satellites, presence of unusual satellites on chromosome 17, deletion of the short arm of a D-chromosome, lengthening of chromosome 16, and chromosome breaks.
The remaining 56 patients were studied for familial congenital heart disease. Two chromosomal abnormalities were detected in this group.
If the classical aberrations are included, the frequency of chromosomal abnormalities as a cause of congenital heart disease may be estimated at between 3 and 5%. This figure should be considered in relation to the methods of recruitment which excluded all patients less than 3 years of age.
Vascular Changes in Pulmonic Stenosis and Tetralogy of Fallot Studied in Lung Biopsies
Authors: WAGENVOORT C. A. , NAUTA J. , VAN DER SCHAAR P. J. , WEEDA H. W. H. , WAGENVOORT NOEKE 
Published: June 2012

The present study deals with the results of the histological investigation of lung biopsies from 44 patients with pulmonic stenosis and 117 with tetralogy of Fallot in correlation with their clinical and hemodynamic data. Particularly cases without additional complicating malformations have been considered.
Medial atrophy and luminal widening of the muscular pulmonary arteries and veins were confirmed in both isolated pulmonary stenosis and tetralogy of Fallot but were more marked in pulmonic stenosis. Intimal fibrosis in the pulmonary vessels on the other hand gave the impression of being greater in the cases of tetralogy of Fallot than in pulmonic stenosis even within the same age group, but this difference is not statistically significant. Intimal fibrosis was even more pronounced in tetralogy of Fallot with a previous shunt operation. The intimal fibrosis is thought to be based on organization of thrombi.
The explanations for the medial atrophy and the widening of the arterial lumen are unknown, but it is thought likely that the flatness of the pressure curve in the pulmonary artery plays a role in causation.
Double-Inlet Left Ventricle
Authors: DE LA CRUZ MARÍA V. , MILLER B. LYNN 
Published: June 2012

Two pathological specimens are presented in which the morphological left ventricle contains the right atrioventricular ostium, completely or in its major portion and, totally, the left atrioventricular ostium. It is suggested from a consideration of these cases and of the pathological material available in the literature that this constitutes an entity that can be usefully separated from the heterogeneous group of single ventricle with which it has previously been classified. The entity is called double-inlet left ventricle and is defined as existing when two separate atrioventricular ostia open in a morphological left ventricle.
An ontogenetic explanation is presented based on the study of normal human embryos. These cases resemble the heart of the embryo during the horizons XIII to XVI of Streeter. It is suggested that there has been a partial arrest in the widening of the atrioventricular canal and the changing relation of the atria with the ventricles at these stages.
It is noted that both atria open into the morphological left ventricle whether situated to the left or to the right. This is an expected finding, since the left ventricle is derived from the primitive ventricle and the primitive ventricle is always connected with both atria during the early stages of embryological development.
Other malformations include transposition of the great arteries in both cases and ventricular inversion in one.
Hypertensive Retinopathy
Authors: RAMALHO P. S. , DOLLERY C. T. 
Published: June 2012

Caliber changes in retinal vessels of groups of hypertensive patients were measured after the blood pressure had been lowered by successful renal surgery, posture with adrenergic blocking drugs, and parenteral hydralazine. The small arterioles dilated when the pressure was reduced, whatever means were used. Larger arterioles dilated in three younger hypertensive patients but in the remainder they were unchanged or narrowed by pressure reduction.
Inhalation of oxygen constricts normal retinal arterioles but the response in hypertensive patients was much less. A response to oxygen was restored in some small arterioles that dilated when the blood pressure was lowered.
As retinal arterioles have no adrenergic vasomotor supply, changes in their caliber probably occur because of autoregulation. Narrowing caused by autoregulation during a rise in systemic arterial pressure may become irreversible in long-standing hypertension because of structural changes in the vessel wall.
Influence of a Defoaming Agent upon the Hematological Complications of Pump Oxygenators
Authors: WELLS ROE , BYGDEMAN M. STELLAN , SHAHRIARI ALI A. , MATLOFF JACK M. , Geyer Robert P. , Harken Dwight E. 
Published: June 2012

Measurements of plasma hemoglobin values were made at many different sites of a Cross-Kay disk pump oxygenator during extracorporeal bypass in patients undergoing reparative valve surgery. Hemoglobin values were always higher in the line of the aspirator and defoaming chamber than in any other part of the system. Sampling immediately proximal and distal to the defoaming chamber revealed significant increases in plasma hemoglobin values as a result of the defoaming process.
Studies of the hematological effects of the defoaming agent, polymethylsiloxane, which coats the disposable stainless steel sponge in the defoaming chamber, showed it greatly reduced the resistance of red cells to lysis by mechanical trauma. Similar studies of plasma showed the hemolytic effects of the defoaming agent are to some extent mediated by the plasma.
It is concluded that the widely used defoaming agent, polymethylsiloxane, contributes to the hemolytic action of the bubbling, suctioning, and defoaming processes during open heart surgery. The addition of a water soluble surfactant material, that stabilizes emulsions (Pluronic F68), blocked or prevented the hemolytic process without interfering with the action of the antifoam material.