bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hemodynamic Studies One Year After Homograft Aortic Valve Replacement
Authors: KENNEDY J. WARD , TWISS R. D. , BLACKMON J. R. , MERENDINO K. ALVIN 
Published: June 2012

Clinical and hemodynamic evaluation has been carried out one year after homograft aortic valve replacement in 15 patients. These studies have included an evaluation of pressure gradients across the aortic valve, supravalvular cineangiocardiography, and left atrial biplane angiocardiography for the measurement of left ventricular volume, left ventricular mass, and quantitation of aortic regurgitation. Eight patients had an excellent result, three patients a good result, and three patients a fair result. One patient had a poor result because of persistent, severe aortic regurgitation. A small systolic pressure gradient was present across the homograft valve in 2 of 13 patients. Significant aortic regurgitation, defined as more than 3 L/min, occurred in four patients.
Patients with aortic regurgitation preoperatively had reduction in LV volume in proportion to the reduction in regurgitation after surgery. Left ventricular mass diminished postoperatively in proportion to the reduction in stroke work, as determined from the pressure-volume diagram.
Laboratory and Clinical Studies during Prolonged Partial Extracorporeal Circulation Using the Bramson Membrane Lung
Authors: HILL J. DONALD , BRAMSON M. L. , HACKEL ALVIN , DEAL CEDROC W. , SANCHEZ PEDRO A. , OSBORN JOHN J. , GERBODE FRANK 
Published: June 2012

The survival rate, electrolyte changes, hematological changes, arterial gas analysis, and pulmonary compliances in 14 prolonged venovenous perfusions with the Bramson membrane oxygenator are presented. The Bramson membrane oxygenator functioned efficiently.
There were two deaths in the series, neither attributable to the perfusion. Arterial gas studies and pulmonary compliance studies indicated no measurable detrimental effect on the lungs. Platelet counts decreased and white blood cell counts increased during perfusion.
A clinical prolonged veno-venous perfusion is reported.
Epicardial Pacing to Control Arrhythmias Following Cardiac Surgery
Authors: HARRIS PAUL D. , MALM JAMES R. , BOWMAN FREDERICK O. , HOFFMAN BRIAN F. , KAISER GERARD A. , SINGER DONALD H. 
Published: June 2012

Epicardial electrodes were chronically implanted on the surface of atria and ventricles in 60 patients at the time of open-heart surgery. Eighteen patients developed bigeminy or multiple premature ventricular contractions associated with slow heart rates in the immediate postoperative period. The ectopic ventricular activity was abolished by pacing the atria or ventricles faster than the spontaneous cardiac rate. In seven patients, low cardiac output associated with low heart rates was improved by pacing at more optimal rates.
When feasible, atrial pacing is preferred to ventricular pacing to utilize atrial systole to improve ventricular filling and increase cardiac output. The safety and ease of implantation of these electrodes enable them to be used routinely for diagnostic and therapeutic application in all patients undergoing open-heart surgery.
Femoropopliteal Bypass Grafts Utilizing Autogenous Veins
Authors: CALDWELL ROBERT L. , DEWEESE JAMES A. , ROB CHARLES G. 
Published: June 2012

The results of 157 consecutive autogenous saphenous vein bypass grafts followed for periods up to eight and a half years are presented. The operations were performed on 145 patients with the following indications: (1) intermittent claudication (41%); (2) rest pain (25%); (3) gangrene (34%).
The early patency rate in patients with intermittent claudication was 83%, and of these 83% remained patent; with rest pain, 74% and of these 86% remained patent; with gangrene, 63% and of these 76% remained patent.
The success rate was highest in (1) nondiabetic patients; (2) extremities with two or three patent vessels at the level of the popliteal trifurcation; (3) extremities in which short grafts were used, whether or not the reconstruction crossed the knee joint.
Angiograms on 29 patent grafts and 12 thrombosed grafts revealed: (1) absence of atheromatous changes in the grafts; (2) absence of aneurysmal dilatation in the body of the graft; (3) an equal incidence of progression of original disease in patent grafts and in late thrombosed grafts.
Autogenous venous bypass grafts function well in the arterial system for prolonged periods. The results continue to support the superiority of vein grafts over both thromboendarterectomies and synthetic-tube bypass grafts in the treatment of femoropopliteal occlusive disease.
Erythrocyte Destruction by Prosthetic Heart Valves
Authors: INDEGLIA ROBERT A. , SHEA MICHAEL A. , VARCO RICHARD L. , BERNSTEIN EUGENE F. 
Published: June 2012

Immediate hemolysis induced by eight aortic and five mitral valve prostheses was measured in in vitro steady- and pulsatile-flow systems. The mean index of hemolysis (IH) for the aortic valves ranged from 0.010 to 0.031 and 0.012 to 0.035 with steady and pulsatile flow, respectively. The IH for the mitral valves ranged from 0.004 to 0.021 in the steady-flow system, and from 0.011 to 0.021 in the pulsatile system.
The Barnard-UCT aortic valve and the Kay-Shiley and Portex-Hammersmith mitral valves produced the least hemolysis in each group. The graphite-benzalkonium-heparin-coated Gott-Daggett valve was the most hemolytic valve in both the mitral and the aortic groups.
The degree of hemolysis demonstrated in these experiments appears to be important, particularly since several factors which are likely to have minimized these data have been cited. The calculated daily hemoglobin released from a single prosthetic valve represents a substantial fraction of a human's total hemoglobin clearance capacity and red cell regenerative capability.
Autoimmune Studies in Patients with Primary Myocardial Disease
Authors: FLETCHER, M.D. GERALD F. , WENGER NANETTE K. 
Published: June 2012

Heart immunofluorescent autoantibody tests, the complement fixation test for Chagas' disease, the hemagglutination test for toxoplasmosis, and the latex flocculation test for rheumatoid disease were compared in 34 patients with primary myocardial disease and their paired control subjects. There was no difference in the incidence of elevated titers or in the actual titer levels between the group with primary myocardial disease and the control group for any of these tests.
This study is limited in that it gives no information about an agent or mechanism for primary myocardial disease which is no longer demonstrable by serological test, particularly since the patients with primary myocardial disease were studied, at an average, 6 years after onset of symptoms. It is also possible that agents or mechanisms other than those included in this study may be causative of primary myocardial disease.

We have, however, demonstrated that there is
no
serological evidence associating the parasites or immunological responses studied with the clinical syndrome of chronic primary myocardial disease.
The Biology of Myocardial Infarction
Authors: BIÖRCK GUNNAR 
Published: June 2012

Myocardial infarction is a dreaded companion of the civilization of our time. The "heart attack," the coronary thrombosis, the myocardial infarction lurk behind the corner, striking strangers, patients, friends, and ourselves. The toll taken by this single "disease" in many hospitals equals or even exceeds that from almost all other diseases together. Must it be so? This is the question many physicians, and the lay public, are asking themselves today.
Identification of some areas where our knowledge is particularly deficient is stressed. We must concentrate our efforts on reevaluating practices and procedures that have brought both the greatest success and the worst failures, at the same time that we ask ourselves what goals could be considered realistic.
If myocardial infarction is the evil of our time, what does this mean in a greater biological context-in the evolution of human life and endeavor as viewed in perspective? Are we dealing with a "disease" in the restricted sense of the word, or are we dealing with a way of life and a consequent mode of death? If so, what can be done to achieve the goals of health as defined by the World Health Organization? In what terrain are the forces to be assembled and the battle to be fought-and by whom.
Left Ventricular Pressure-Volume Characteristics in Congenital Heart Disease
Authors: JARMAKANI M. M. , EDWARDS SAM B. , SPACH MADISON S. , CANENT RAMON V. , CAPP M. PAUL , HAGAN MARY J. , BARR ROGER C. , JAIN VISHNU 
Published: June 2012

The continuous pressure-volume relationships throughout the cardiac cycle were evaluated in children with tetralogy of Fallot, isolated ventricular septal defect, and patent ductus arteriosus. Biplane cineangiocardiography and simultaneous left ventricular pressures were utilized for data acquisition. Normal pressure-volume loops demonstrated only small changes in left ventricular volume during the isovolumic periods. In tetralogy of Fallot, there was a decrease in left ventricular volume during the interval of the "isovolumic" contraction with 12 to 43% of the total stroke volume being ejected during this phase. A decrease in left ventricular volume during this time was also found in large ventricular septal defects; however, volume changes during this interval were minimal in those patients judged to have small defects.
With large left-to-right shunts of comparable magnitude, the relative area of the pressure-volume loop was greater in patent ductus arteriosus as compared with ventricular defects. Both conditions demonstrated marked increase in stroke volume, with peak systolic pressures rising higher in those patients with patent ducus arteriosus as compared to those with ventricular septal defect.
Atrioventricular Pressure Half-Time
Authors: LIBANOFF ALBERT J. , RODBARD SIMON 
Published: June 2012

In 20 patients studied by cardiac catheterization, the time required for the diastolic left atrioventricular pressure difference to fall to half its initial value (half-time) varied with the anatomic severity of the valvular stenosis. In mild mitral stenosis, the half-time was approximately 100 msec; in moderate stenosis, it was about 200 msec; and it was 300 msec or longer in severe stenosis. The half-time at the nonstenotic mitral valve was less than 25 msec.
Although exercise increased the atrioventricular pressure gradient, heart rate, and cardiac output significantly, the half-time was affected only slightly. Mitral regurgitation of various severities did not affect the half-time. The half-time appears to vary inversely with the anatomic orifice area of the mitral valve. The determination of the half-time obviates the need for the commonly used exercise test for the evaluation of mitral stenosis.
Correlation of Vectorcardiogram and Electrocardiogram with Coronary Arteriogram
Authors: LEE GERALD B. , WILSON WILLIAM J. , AMPLATZ KURT , TUNA NAIP 
Published: June 2012

One hundred patients with suspected coronary heart disease were studied by vectorcardiography (VCG), electrocardiography (ECG), and coronary arteriography. Twenty-eight patients had VCG evidence of anterior infarction; 26 of this group had severe narrowing or obstruction of the left anterior descending branch. Five did not have anterior infarction by ECG.
Twenty-seven patients had VCG evidence of diaphragmatic infarction; 25 of this group had severe narrowing of the right coronary artery or the left circumflex branch or both. Six of the 27 did not have ECG evidence of diaphragmatic infarction.
Twelve patients had VCG evidence of posterior infarction whereas it was detected by ECG in only two. Only six of the 12, however, had severe narrowing of the nutrient arteries to the posterobasal part of the myocardium.
Thirteen patients with infarction had severe narrowing but not total obstruction of a coronary artery. On the other hand, 15 patients had total obstruction of a major coronary vessel without actual infarction.
Hemodynamic Studies Before and After Instrumental Mitral Commissurotomy
Authors: FEIGENBAUM HARVEY , LINBACK RICHARD E. , NASSER WILLIAM K. 
Published: June 2012

Hemodynamic studies including simultaneous right heart, transseptal left heart, and retrograde left heart catheterizations were done on 35 patients before and at least 6 months after instrumental mitral commissurotomy to evaluate the efficacy of this type of surgery and to enhance our understanding of the pathophysiology of mitral stenosis. Although surgery produced a significant increase in calculated mitral valve area, the degree of improvement varied markedly. The younger patients had the greater increase in mitral valve area. The change in cardiac index and pulmonary vascular resistance correlated well with the change in mitral valve area. Only those patients whose mitral valve area increased over 1.0 cm
2
had a significant increase in cardiac index and a fall in pulmonary vascular resistance. The data indicate that the reduced cardiac index and elevated pulmonary vascular resistance in patients with mitral stenosis are related to the mitral valve obstruction and are at least in part reversible and that the elevated pulmonary vascular resistance during mild exercise is related to elevated left atrial pressure.

An almost universal fall in left atrial and pulmonary artery pressures followed surgery, but this apparent improvement did not necessarily correlate with an increase in mitral valve area. A significant increase in exercise left ventricular end-diastolic pressure in patients who had the greatest increase in mitral valve area raises the question as to the status of the left ventricle in patients with mitral stenosis. Decreased left ventricular compliance is offered as a possible explanation for this observation.
The concomitant existence of mild or moderate preoperative aortic insufficiency in eight of the patients and the development of significant mitral insufficiency in seven of the 35 patients following surgery did not alter the surgical results significantly. Whether the poorer results in patients with atrial fibrillation were a result of age or the arrhythmia could not be determined.
Transposition of the Great Vessels with Hypoplasia of the Right Ventricle
Authors: RIEMENSCHNEIDER THOMAS A. , VINCENT WILLIAM R. , RUTTENBERG HERBERT D. , DESILETS DONALD T. 
Published: June 2012

Eight cases are reported in which complete transposition of the great vessels was associated with varying degrees of hypoplasia of the right ventricle. In three, the correct diagnosis was suspected on the basis of certain electrovectorcardiographic findings and confirmed by selective angiography. Quantitative analysis of ventricular volumes and valve circumferences demonstrated that these cases represent a distinct pathological entity.
The diagnosis of complete transposition with hypoplastic right ventricle may be suggested by electrocardiographic evidence of left ventricular hypertrophy, relative absence of right ventricular QRS vectors, and leftward axis for age. The vectorcardiogram reveals a counterclockwise QRS loop in the horizontal plane, situated to the left and posteriorly. These findings occur infrequently in the young infant with complete transposition.
The presence of a hypoplastic right ventricle is confirmed by angiography, which demonstrates a small right ventricular chamber located centrally in the cardiac silhouette, not extending beyond the left border of the thoracic spine.
Hemolytic Anemia Due to Progressive Enlargement of Silastic Ball Component of Aortic Prosthesis
Authors: GARCIA MARIO C. , CLARYSSE ALBERT M. , ALEXANDER CARL S. , SAKO YOSHIO , SWAIM WILLIAM R. 
Published: June 2012

The patient described developed hemolytic anemia following insertion of a Starr-Edwards aortic valve prosthesis. No diastolic murmur was heard and no insufficiency was detected. The hemolytic anemia was progressively more severe and uncompensated despite various medical measures.
The anemia was characterized by fragmented erythrocytes in the peripheral blood, reticulocytosis, elevation of plasma heme pigments augmented by exercise, increased fecal urobilinogen, and iron loss in the urine. Studies of chromium-51-tagged erythrocytes indicated an extracorpuscular mechanism of hemolysis.
At reoperation the ball component of the prosthesis was found to be enlarged and obstructing blood flow. Chemical analysis of the ball showed significant cholesterol and lipid deposits. The hemolysis disappeared after the prosthesis was replaced with a homograft valve. Ferrokinetic studies showed rapid plasma clearance and incorporation into circulating erythrocytes. Triglycerides were elevated during the period of hemolysis. Red cell membrane lipids were normal.
Computer Quantitation of the ST-Segment Response during Maximal Treadmill Exercise
Authors: MCHENRY PAUL L. , STOWE DARWELL E. , LANCASTER MALCOLM C. 
Published: June 2012

The ST-segment response during maximal treadmill exercise was quantitated by digital computer after excessive noise in the electrocardiographic data was reduced by computer averaging. Both the slope and the depression were quantitated.
Two groups of subjects were studied. Group A consisted of 35 subjects between 33 and 57 years of age with confirmed or suspected coronary artery disease. Group N consisted of 73 clinically normal subjects between 24 and 52 years of age. The responses of the group A subjects and the 26 subjects over age 35 in group N were compared by graphically plotting their ST slope and depression values from the last minute of exercise. A linear discriminant analysis computed from these values resulted in a line of separation between the majority of subjects in each of these two groups. This separation was accomplished even though the majority of subjects in group A did not demonstrate segmental ST depression.
The Conduction System in Acute Myocardial Infarction Complicated by Heart Block
Authors: SUTTON RICHARD , DAVIES MICHAEL 
Published: June 2012

Detailed histological examination of the conduction system in 29 cases of acute myocardial infarction complicated by heart block has been carried out. In 24 cases posterior infarction was present and occlusion had occurred in the artery from which the blood supply to the A-V node was ultimately derived. In these cases major structural damage to the conduction system was rare, but when present, involved the bundle branches. A-V block in posterior infarction is therefore usually due to hypoxia or other reversible factors rather than structural damage to the conduction system. These findings are consistent with the high incidence of transient heart block in survivors.
In five cases anterior infarction alone was present. The blood supply of the A-V node was not compromised, but massive infarction had caused major damage to both bundle branches.
Since major structural damage to the conduction system is uncommon in myocardial infarction, only a minority of survivors will have permanent heart block. In those cases in which there is extensive damage to the bundle branches there is a risk of high mortality and permanent block particularly when the infarct is anteroseptal.
Immediate Hemodynamic Response of Patients with Atrioventricular Block and Cardiac Failure to Transvenous Pacing
Authors: GOBEL FREDARICK L. , MEDINA JOSE R. , GUENTER CLARENCE A. , WANG YANG , Olds David P. 
Published: June 2012

Immediate hemodynamic improvement in patients with complete heart block occurs when the ventricular rate is increased by electrical pacing. During pacing, there is reduction in the pulmonary artery wedge, right atrial, and left and right ventricular filling pressures. The mean rate of ejection, stroke volume, and stroke work decreased following pacing, whereas the ejection time per minute increased, and dye curves assumed a more normal configuration. Very little change was noted in the resting cardiac output.
The paced heart is able to obtain greater increases in cardiac output, stroke volume, and mean rate of ejection during exercise than when unpaced. In addition, pacing tends to return elevated exercising filling pressures in the right and left ventricles toward normal.
Complete Repair of Transposition of the Great Arteries with Pulmonary Stenosis
Authors: RASTELLI G. C. , WALLACE ROBERT B. , ONGLEY PATRICK A. 
Published: June 2012

Complete surgical correction of transposition of the great arteries associated with subvalvular pulmonary stenosis carries a high mortality rate. A new surgical technique that achieves redirection of the ventricular outflows and relieves pulmonary stenosis by bypassing it, was successfully used to repair complete transposition of the great arteries associated with ventricular septal defect (VSD) and valvular and subvalvular pulmonary stenosis in a 14½-year-old patient. The repair consists of (1) division of the pulmonary artery, the cardiac end of which is oversewn, (2) repair of the VSD with a patch in such a way as to connect the left ventricle with the aorta, and (3) reconstruction of the pulmonary artery with an aortic homograft, including the aortic valve, which is anastomosed between the distal end of the pulmonary artery and the right ventricle.
A review of the cases in which the current techniques were used indicates that the location and nature of the obstruction in the left ventricular outflow tract defies successful repair in most instances. Localized ridges and diffuse hypoplastic outflow tracts are recognized causes of obstruction, but anomalies of the mitral valve commonly contribute to or are the primary cause of subvalvular obstruction.
The Familial Occurrence of the Syndrome of Mid-Late Systolic Click and Late Systolic Murmur
Authors: SHELL WILLIAM E. , WALTON JOSEPH A. , CLIFFORD MARY E. , WILLIS PARK W. 
Published: June 2012

Patients with late systolic murmurs, with and without mid-late systolic extra sounds, have recently been shown to have mitral regurgitation. This syndrome has been found to be familial in each of the four families we have studied. These families were found to have a high prevalence of mid-late systolic extra sounds, late systolic murmurs, pansystolic murmurs, abnormal electrocardiograms, and unexplained premature sudden death.
The prognosis for these patients is unknown but is generally considered good. Periodic medical observation of these patients and their families seems warranted, however, in view of the current lack of knowledge concerning the cause of the chest pain, the rate of progression of the mitral regurgitation, the significance of the electrocardiographic abnormalities, the frequency of important arrhythmias, and the mechanism of sudden death. In addition, antibiotic prophylaxis to attempt to prevent bacterial endocarditis seems clearly indicated.