bluuebunny/crossref_metadata_2025 huggingface dataset:
Abnormal Mitral Valve Motion in Patients with Elevated Left Ventricular Diastolic Pressures
Authors: KONECKE LEE L. , FEIGENBAUM HARVEY , CHANG SONIA , CORYA BETTY C. , FISCHER JOHN C.
Published: June 2012

In order to see whether or not the echocardiographically recorded mitral valve could reflect alterations in left ventricular pressure, simultaneous mitral valve echograms and left ventricular pressures were obtained on patients undergoing diagnostic cardiac catheterization. Attention was given to the left ventricular initial diastolic pressure (LVIDP), left ventricular end-diastolic pressure (LVEDP), and the atrial component of the left ventricular pressure (LV
a
). The echocardiographic measurements included the opening velocity of the mitral valve in early diastole (D-E slope) and the interval between the A point, which is the onset of closure of the mitral valve following atrial systole, and the C point, which represents closure of the mitral valve as indicated by the meeting of the anterior and posterior mitral leaflets. In order to compensate for variations in atrioventricular conduction, the A-C interval was subtracted from the electrocardiographic P-R interval. In 19 patients, the LVIDP was less than 14 mm Hg, the LVEDP was less than 20 mm Hg, and the LV
a
was less than 8 mm Hg. In these patients, the D-E slope was greater than 25 cm/sec and the PR-AC interval was greater than 0.06 sec. Six patients who had an LVIDP of 14 mm Hg or greater had a D-E slope of less than 25 cm/sec. There were 14 patients with an LVEDP greater than 20 mm Hg and an LV
a
of 8 mm Hg or greater. All of these patients had a PR-AC interval of less than 0.06 sec. There were an additional three patients who had an LVEDP above 20 mm Hg, but whose LV
a
was less than 8 mm Hg. In these three patients, the PR-AC interval was greater than 0.06 sec. Thus, the shortened PR-AC interval correlated primarily with an elevated LV
a
. This study indicates that the echocardiographic pattern of mitral valve motion is altered in patients who have markedly elevated left ventricular diastolic pressures.
Left Ventricular Size after Acute Myocardial Infarction
Authors: KOSTUK WILLIAM J. , KAZAMIAS THOMAS M. , GANDER MARTIN P. , SIMON ALLAN L. , ROSS JOHN
Published: June 2012

The distance from the midline to the left heart border measured in a standardized manner on calibrated chest roentgenograms was determined serially in 125 patients after acute myocardial infarction. This external left heart dimension (LHD) was compared to the normal value, and its prognostic value was assessed during early and late follow-up periods (average 10½, range 2-31 months). Within 96 hours after acute myocardial infarction the initial LHD was enlarged (>52 mm/m
2
BSA [body surface area]) in 42% of the patients. The LHD became normal, or remained persistently normal in 60% of the 115 patients without shock, and it became enlarged or remained persistently enlarged in 40%. If the 10 patients with cardiogenic shock are excluded, early death (<4 weeks) occurred in three of 68 patients (4%) with initially normal LHD, and in 12 of 47 patients (26%) with initially enlarged LHD (
P
< 0.001). The LHD remained normal or became normal in 62 of 96 patients followed who survived more than 1 month. During the follow-up period, 8% of patients with a normal LHD have died and the remainder (with one exception) are in New York Heart Association (NYHA) class I or II. Only 5% of this group died of acute cardiac causes. In 34 patients the LHD became or remained persistently enlarged; of these patients 24% have expired (
P
< 0.05) and 42% are in NYHA class III (
P
< 0.001). This study validates a method for the early detection and serial assessment of left ventricular enlargement and indicates that the LHD is a useful predictor of survival and morbidity after acute myocardial infarction.
Electrophysiologic Properties of Diphenylhydantoin
Authors: CARACTA ANTHONY R. , DAMATO ANTHONY N. , JOSEPHSON MARK E. , RICCIUTTI MICHAEL A. , GALLAGHER JOHN J. , LAU SUN H.
Published: June 2012

The electrophysiologic properties of diphenylhydantoin (DPH) (5-10 mg/kg) intravenously was studied in 14 subjects using His bundle recordings and correlated with blood levels. Conduction through the A-V conducting system (AVCS) was studied at various paced atrial rates and refractory periods determined using programmed atrial premature depolarization within 10 min of drug administration. In 11 of 14 subjects the sinus cycle length was shortened by an average of 110 msec, lengthened in three (average 116 msec). Conduction through the A-V node (AVN) was shortened in seven subjects (average 10 msec), lengthened in one (5 msec), and unchanged in the remaining six. Conductinged by 5 msec). Prior to DPH, the longest mained constant in all but two subjects (proloengthened in four, and was unchanged in the re-refractory period of the AVCS was in the AVN in nine subjects, the atrium in four and the HPS in one. After DPH, the following effects were noted: (1) the effective refractory period (ERP) of the atria shortened in four subjects, lengthened in four, and was unchanged in the remaining six; (2) the ERP of the AVN shortened in 6/9 subjects, lengthened in 3/9; (3) functional refractory period of AVN shortened in six, prolonged in three subjects, and remained unchanged in five subjects; (4) the relative refractory period (RRP) of the HPS shortened in 7/7 subjects; (5) ERP of HPS in 1/1 subject shortened. Thus, DPH showed varied effects on A-V nodal conduction, inconsistent effect in the atrium, and consistent shortening of the refractory period of the HPS. The data suggest DPH differs from other antiarrhythmic drugs such as quinidine and procaine amide.
Nonrheumatic Subvalvular Mitral Regurgitation
Authors: CAVES PHILIP K. , SUTTON GEORGE C. , PANETH MATTHIAS
Published: June 2012

Thirty-three patients are reported with nonrheumatic mitral regurgitation due to rupture or stretching of the chordae tendinaeae or papillary muscles. Nineteen (58%) had no definite predisposing etiological factors (average age 59 years). Six (19%) had a previous myocardial infarction. It is proposed that rupture or stretching of the chordae resulted from degenerative or ischemic changes in the chordae and/or papillary muscles. Six young patients had ruptured chordae from other causes. Two patients had myocardial infarction resulting in rupture of the posteromedial papillary muscle.

Characteristic clinical findings included progressive dyspnea of sudden onset, sinus rhythm, systolic thrill, accentuated pulmonary valve closure sound, third heart sound, and widely propagated pansystolic murmur. The electrocardiogram frequently showed inferolateral ischemic changes. Plain chest radiographs usually showed a normal-sized heart and left atrium in patients in sinus rhythm. At cardiac catheterization a characteristic high V wave in the pulmonary artery wedge pressure was seen in 88% of patients. The left ventricular end-diastolic pressure was highest in the six postinfarct patients in whom the ejection fraction was significantly low.
Infra-His Bundle Origin of Bidirectional Tachycardia
Authors: COHEN STAFFORD I. , DEISSEROTH ALBERT , HECHT HARVEY S.
Published: June 2012

A case of bidirectional tachycardia is presented in a patient with cardiomyopathy, pulmonary emboli, and digitalis toxicity. The arrhythmia has usually been considered ventricular in origin. A supraventricular origin has also been suggested. Simultaneous recordings of standard electrocardiographic leads and His bundle potentials demonstrated that the abnormal rhythm originated in the left ventricle and indeed was a bidirectional ventricular tachycardia. Enhanced phase 4 depolarization in the divisions of the left bundle branch is advanced as a theoretic underlying mechanism in some instances of this arrhythmia.
Prosthetic Valvular Endocarditis
Authors: SLAUGHTER LAURA , MORRIS JAMES E. , STARR ALBERT
Published: June 2012

A retrospective examination was made of a total of 48 patients with infected prosthetic cardiac valves implanted in 1,236 patients during 1960-1972. Survival rate of the valvular infections was 40%. The purpose of the study was to determine the factors which aided or decreased patient survival and to develop a program of treatment with antimicrobial agents. Numerous antimicrobics and a variety of dosage schedules were used. Of 19 surviving patients, medical treatment alone was effective in 14, despite the continued presence of a valvular prosthesis. Reoperation was successful in five of nine patients. Lifelong chemoprophylactic or suppressive therapy was shown to be unnecessary to prevent relapse in 12 survivors. Prompt surgical replacement is indicated if antimicrobial therapy fails to eradicate infection of a prosthetic valve. A more systematic approach to antimicrobial therapy should improve survival of medically treated infections. Recommendations are made for prevention and treatment of prosthetic valvular endocarditis.
Present Status of Electroversion in the Management of Cardiac Dysrhythmias
Authors: RESNEKOV LEON
Published: June 2012

The theoretical and practical considerations of electrical reversion of cardiac dysrhythmias are reviewed and a comparison made between AC and DC defibrillation, indicating the superiority of DC under all circumstances. The indications for, immediate and late results of DC shock for atrial and ventricular dysrhythmias are presented, the complication of such treatment reviewed, and the need for anticoagulant cover, anesthesia, and drug therapy preceding and following the electrical treatment discussed. Each patient requires individual assessment, particularly those with chronic rhythm disturbances, especially atrial fibrillation, in whom electrical energy settings in excess of 300 joules are rarely indicated for the risk of complications becomes progressively higher as the energy setting is increased and the length of time sinus rhythm persists in this group of patients may be short. Patients with acute rhythm disturbances, however, with potentially serious hemodynamic consequences should be treated with maximum electric energies if needed. Caution is also advised in patients with coronary heart disease, atrial fibrillation, and a slow ventricular rate, even in the absence of digoxin, patients with rapidly changing rhythm disturbances, those who cannot maintain sinus rhythm for a significant period of time despite drug therapy, patients with the "sick sinus syndrome," those with atrial fibrillation of more than 5 years standing with a cardiothoracic ratio exceeding 55%, and patients in lone atrial fibrillation. Heavily digitalized patients in general should have their electroversion postponed if possible, but if not, they should be protected against serious ventricular rhythm disturbances immediately after the shock by an intravenous dose of lidocaine, phenylhydantoin, or procaine amide immediately before and the initial energy setting should be reduced to 5 joules. Quinidine or some other antidysrhythmic drug may be needed in an attempt to maintain sinus rhythm after successful electroversion, but even when controlled with adequate blood levels, results are poor.
Antihypertensive and Hemodynamic Properties of the New Beta Adrenergic Blocking Agent Timolol
Authors: FRANCIOSA JOSEPH A. , FREIS EDWARD D. , CONWAY JAMES
Published: June 2012

The antihypertensive activity of timolol, a new beta adrenergic blocking agent, was assessed in hypertensive patients. In hospitalized patients timolol, 5 mg orally every 8 hr for one week, resulted in a significant although mild reduction of blood pressure with diastolic pressure falling from a mean of 101 mm Hg to 91 mm Hg. Heart rate and cardiac output fell while total peripheral resistance increased. The Valsalva response, the reflex tachycardia following inhalation of amyl nitrite and the cardiovascular responses to infusion of isoproterenol were significantly inhibited. Timolol also was compared to propranolol in a randomized double-blind outpatient trial. The antihypertensive and bradycrotic effects of the two drugs were similar. Heart rate was reduced 18% by both drugs (
P
< 0.05). Supine diastolic pressure fell 9% (
P
< 0.05). Unlike the short term effects of timolol, and in contrast to propranolol, cardiac output did not remain reduced after five weeks of continuous treatment with timolol. It is concluded that timolol merits further investigation as an antihypertensive agent.
Evaluation of Enzyme Testing for the Detection of Myocardial Infarction Following Direct Coronary Surgery
Authors: ALDERMAN EDWIN L. , MATLOF HARVEY J. , SHUMWAY NORMAN E. , HARRISON DONALD C.
Published: June 2012

The serial measurement of postoperative serum enzymes has been proposed as an important method for identifying myocardial infarction following aortocoronary graft surgery. Serum glutamic oxalacetic transaminase, creatine phosphokinase and lactic dehydrogenase levels were determined during the initial five days following direct coronary artery surgery in 112 patients. Enzyme test results were analyzed by frequency distribution plots. Twelve patients (10.7%) developed definite electrocardiographic evidence of myocardial infarction within two weeks of surgery, seven on the first postoperative day. A general correlation of higher serum enzyme values and electrocardiographic evidence for myocardial infarction was established. However, the use of arbitrarily selected 90th percentile enzyme levels yielded a substantial number of false-negative and false-positive results as compared with electrocardiographic diagnosis. The 90th percentile levels were substantially higher following multi-vessel surgery, compared with single-vessel surgery. Thus, analysis of serum enzymes following coronary surgery was found to be a useful, but not definitive adjunct in identifying patients suspect for operative infarction.
Cardiac Repair in Anatomically Corrected Malposition of the Great Arteries
Authors: KIRKLIN JOHN W. , PACIFICO ALBERT D. , BARGERON L. M. , SOTO BENIGNO
Published: June 2012

Anatomically corrected malposition of the great arteries is a congenital cardiac malformation in which the atria and ventricles are in concordant relation, as are the ventricles and great arteries, but the aorta is to the left of the pulmonary artery (1-position). The reported cases and our two patients have had situs solitus of viscera and atria. The aortic and pulmonary circulations are in series. We report successful surgical repair in 2 patients with associated large ventricular septal defects and pulmonary stenosis. In one the defect was posterior and in relation to the pulmonary artery which slightly overrode it. In the other the defect was anterior and the aorta overrode it. The developmental basis of these two examples of the same entity is probably different. An appropriate terminology and categorization that is useful surgically is presented.
Stress and the Induction of Intravascular Platelet Aggregation in the Heart
Authors: HAFT JACOB I. , FANI KAZEM
Published: June 2012

Intravascular aggregation of platelets similar to that found in dogs after norepinephrine infusion was demonstrated using the electron microscope in the hearts of 20 of 23 rats subjected to two forms of stress (immersion in hot water, 7 of 8 rats; repeated small electric shocks to the feet, 13 of 15 rats). Only one of 14 unstressed rats was found to have similar intravascular platelet aggregates. These findings suggest that catecholamines secreted endogenously during stress are sufficient to cause platelets to aggregate intravascularly and raise the possibility that clinical myocardial infarction occurring during severe or prolonged stress may be caused by catecholamine-induced platelet thrombi which occur at, or travel to, and occlude a coronary artery already narrowed by previous atherosclerosis.
Etiology of Prolongation of the P-R Interval in Patients with an Endocardial Cushion Defect
Authors: WALDO ALBERT L. , KAISER GERARD A. , BOWMAN FREDERICK O. , MALM JAMES R.
Published: June 2012

Conduction time from the region of the sinus node to the region of the atrioventricular (A-V) node was studied during open heart surgery in 13 patients with an endocardial cushion type atrial septal defect, eight patients with a secundum type atrial septal defect, one patient with a sinus venosus type atrial septal defect, and eight patients with an intact atrial septum. Internodal conduction time was prolonged by an average of 37 msec (range 15-69 msec) in patients with an endocardial cushion defect when compared with the other three groups of patients. However, when the atria were paced from the A-V nodal region, the resulting P-R intervals in patients with an endocardial cushion defect were similar to those of patients in the other three groups, a fact that indicates normal A-V nodal-His-Purkinje conduction in patients with an endocardial cushion defect. It was therefore concluded that the prolonged P-R interval which patients with an endocardial cushion defect often manifest is due simply to prolonged internodal conduction time. Further, we have suggested that the data from this study support the concept that specialized atrial internodal pathways play an important role in conduction between the sinus and A-V nodes.
Role of Kinetic Energy in Pulmonary Valvar Pressure Gradients
Authors: RAO P. SYAMASUNDAR , AWA SHOICHI , LINDE LEONARD M.
Published: June 2012

Peak systolic pulmonary valvar pressure gradients are frequently seen in large intracardiac left-to-right shunt lesions. Conventionally, this has been attributed to "relative" pulmonic stenosis. Theoretical considerations suggest that this gradient is due to differences in expression of the total fluid energy. The side pressure, the downstream pressure, the end pressure, and the flow velocity in the pulmonary artery (PA) and the right ventricle (RV) pressure were measured in 11 dogs in the control state, and after increasing the velocity of the pulmonary arterial flow either by administration of isoproterenol or atropine, or by creating an arteriovenous fistula. The RV pressure and the end PA pressure were not significantly different (
P
> 0.05), and were higher (
P
< 0.01) than the side and downstream PA pressure in the control state, but increased to higher levels (
P
< 0.01) after increasing the velocity of flow in the pulmonary artery. The mean pulmonary valve peak systolic gradient (RV-side PA pressure difference) was 8.8 mm Hg in the control state and increased to 19.1 mm Hg after isoproterenol infusion (
P
< 0.01). This change in pulmonary valvar gradient is proportional to the increase in the PA flow velocity.

The side pressure measures only the potential energy, and the end pressure measures both the potential and kinetic energies. In the right ventricle, only the potential energy is recorded where the kinetic energy is practically nonexistent. The difference between the RV (or end PA) pressure and side PA pressure is proportional to velocity of flow in the pulmonary artery and is due to partial transformation of fluid energy into kinetic energy. Thus, our study helps to explain the pressure gradient across the pulmonary valve in large left-to-right shunt lesions. These studies also raise questions as to the validity of interpretations of the gradients produced in the RV outflow tract after isoproterenol or exercise.
Echocardographic Findings in Different Types of Mitral Regurgitation
Authors: BURGESS JUDITH , CLARK RALPH , KAMIGAKI MASANOBU , COHN KEITH
Published: June 2012

Forty-eight patients with mitral regurgitation were studied by echocardiography to establish differential diagnostic features. Six patients with rheumatic mitral insufficiency manifested broad and bright echoes from the anterior mitral leaflets and slowed EF slopes. In the majority of patients with prolapse of the mitral valve leaflets due to rupture or redundancy of the chordae tendineae, a posterior sagging of the CD portion of the thin mitral leaflet echoes was evident. Cases with anterior leaflet rupture revealed increased rate and amplitude of anterior cusp opening with a spiked E point. Eight patients with posterior ruptured chordae tendineae were noted to have a paradoxical diastolic anterior motion of the posterior mitral leaflet. Eight instances of mitral insufficiency due to papillary muscle dysfunction manifested a flat CD segment and characteristic double diamond-shaped pattern of the leaflets, lying within an enlarged left ventricular cavity. In two patients with mitral insufficiency associated with calcification of the mitral annulus, a thickened, intense echo was seen posterior to the leaflets. Echocardiograms taken in the patients with severe mitral insufficiency also demonstrated enlarged left ventricular end-diastolic dimensions, increased stroke volume, and increased amplitude of septal motion. The ejection fraction was usually normal, but in 11 it was reduced, suggesting impaired left ventricular function. Echocardiography is an extremely useful technique in evaluating patients with mitral insufficiency, delineating the etiology and severity of the disease, and aiding in grossly assessing left ventricular function.
Evaluation of Hollow Fiber and Spiral Coil Membrane Oxygenators Designed for Cardiopulmonary Bypass in Infants
Authors: RAWITSCHER ROBERT E. , DUTTON ROBERT C. , EDMUNDS L. HENRY
Published: June 2012

Fourteen 1.4 m
2
hollow fiber and 23 1.5 m
2
spiral coil membrane oxygenators that were designed for total cardiopulmonary bypass in infants were evaluated. Operating procedures and toxicity were studied during total cardiopulmonary bypass and one hour of circulatory arrest at 15° C (rectal) in four monkeys. Oxygen and carbon dioxide transfer, water loss, production of emboli, transmission of pulse waves, and pressure-flow relationships were studied at three different blood flow rates, at hematocrits of 25% and 40%, and at 25° C and 37° C during partial venoarterial bypass in 33 dogs. Linear regression equations were calculated for oxygen and carbon dioxide transfer and for pressure-flow relationships at the different flows, temperatures, and hematocrits. Rated flow (Rf), defined as the blood flow rate at which inlet O
2
saturation of 65% increases to an outlet O
2
saturation of 95%, was calculated for each oxygenator at hematocrit 40 (Rf 40) or hematocrit 25 (Rf 25). The hollow fiber oxygenator had a priming volume of 140 ml, an Rf 40 of 800 ml/min, and an Rf 25 of 1200 ml/min. The spiral coil oxygenator had a priming volume of 208 ml, an Rf 40 of 1400 ml/min, and an Rf 25 of 1800 ml/min. At Rf 40 and inlet pCO
2
50 torr, the hollow fiber oxygenator transferred 8.9 ml CO
2
/100 ml and the spiral coil 5.7 ml CO
2
/100 ml. The performance of the two oxygenators differed, but both functioned very satisfactorily.
Determinants of Survival After Coronary Artery Bypass Surgery
Authors: COLLINS JOHN J. , COHN LAWRENCE H. , SONNENBLICK EDMUND H. , HERMAN MICHAEL V. , COHN PETER F. , GORLIN RICHARD
Published: June 2012

Review of our first 180 consecutive patients undergoing myocardial revascularization surgery at the Peter Bent Brigham Hospital shows that the over-all surgical mortality was 5.5%. Mortality in patients not in shock at the time of operation was 2.3%. The only major determinant of surgical survival appeared to be adequacy of left ventricular contraction, as indicated primarily by an ejection fraction above 40%. Of 116 patients operated on for relief of chronic angina pectoris or the intermediate coronary syndrome, 71% were free of angina 6 to 24 months (average 8.9) after surgery. The aggregate operative and late mortality in this group during the period of follow-up was 4.3%.
Vein Graft Surgery for Coronary Artery Disease
Authors: SHELDON WILLIAM C. , RINCON GUSTAVO , EFFLER DONALD B. , PROUDFIT WILLIAM L. , SONES F. MASON
Published: June 2012

One thousand patients were operated upon with vein graft techniques for severe coronary artery obstructions between May 1967 and July 1970, with a hospital mortality rate of 4% and a 5.6% incidence of angiographically confirmed in-hospital myocardial infarctions. Postoperative angiograms, performed in 619 of the survivors, revealed patency of one or more vein grafts in 84.2% of patients, and 82.5% of all grafts were patent in studies performed 1 to 49 months after surgery.

The hospital survivors were followed for 22 to 60 months; only three patients were lost to follow-up. The survival curve for this group of patients was compared with that of another group of 469 patients who also had severe coronary artery disease and were potential surgical candidates, but were studied in an earlier period and did not have surgical treatment. The annual rate of attrition for each of the four years of follow-up in the surgical group averaged 4.8% per year (2.5% per year excluding hospital mortality), and 9.3% per year in the nonsurgical group. Remission of symptoms correlated closely with the completeness of revascularization.

Myocardial revascularization with vein graft techniques can be accomplished successfully and with low risk in the majority of properly selected patients, resulting in a significant improvement in symptoms, as well as in long-term survival.
Lesions Observed in Arterial Autogenous Vein Grafts
Authors: JONES MICHAEL , CONKLE DAVID M. , FERRANS VICTOR J. , ROBERTS WILLIAM C. , LEVINE FREDERICK H. , MELVIN DAVID B. , STINSON EDWARD B.
Published: June 2012

Autogenous vein grafts used for canine femoral and aortocoronary arterial bypasses were evaluated from 2 to 365 days postoperatively. Femoral grafts showed focal endothelial disruption, mural fibrin deposition, and medial edema with inflammatory infiltrates during the first week; loss of medial smooth muscle cells and focal subendothelial lesions with intact endothelium by 2 weeks; and diffuse subendothelial lesions by 12 weeks, Coronary grafts studied at 6, 9, and 12 months had medial fibrosis and extensive intimal proliferation causing up to 90% luminal narrowing. Extension of the intimal process into the coronary artery distal to the bypass graft also compromised the arterial lumen. Coronary grafts obtained from humans dying 17 and 57 days after graft insertion revealed a similar subendothelial proliferation.

Electron microscopy showed that the subendothelial lesions were composed of mature smooth muscle cells and collagen primarily oriented parallel to the axis of blood flow. Recurrent endothelial cell damage, followed by mural fibrin deposition and organization, appears to be the cause of the subendothelial proliferative lesions.
Early and Late Result of Saphenous Vein Graft for Anomalous Origin of Left Coronary Artery from Pulmonary Artery
Authors: EL-SAID GALAL M. , RUZYLLO WITOLD , WILLIAMS ROBERT L. , MULLINS CHARLES E. , HALLMAN GRADY L. , COOLEY DENTON A. , MCNAMARA DAN G.
Published: June 2012

The early and late postoperative angiographic status of the aortocoronary artery saphenous vein graft was studied in six children treated surgically for anomalous origin of left coronary artery from the pulmonary artery. Anastomosis was made to the main left coronary artery in five and to the left anterior descending coronary artery in one. At the first postoperative heart catheterization five of the six vein grafts were found to be patent without stenosis, dilatation, or wall irregularity. The second, late postoperative study performed in the five patients with initially patent grafts showed that one graft had occluded, two had stenosed at the site of the anastomosis with the coronary artery, and one had dilated distally. At the time of the second postoperative study, the treadmill exercise test was normal in three patients, slightly abnormal in the patient with graft stenosis at the site of anastomosis to the left anterior descending coronary artery, and distinctly abnormal in the patient with the occluded graft. Aortocoronary artery saphenous vein graft is a technically successful operation for anomalous origin of the left coronary artery from the pulmonary artery, but obliterative changes may occur in the vein graft in children who are apparently free from atherosclerotic coronary artery disease.
Valve Replacement for Bacterial and Fungal Endocarditis
Authors: UTLEY JOE R. , MILLS JOHN , HUTCHINSON JOHN C. , EDMUNDS L. HENRY , SANDERSON RICHARD G. , ROE BENSON B.
Published: June 2012

Twenty-eight of 143 patients treated for infective endocarditis had replacement of one or more cardiac valves within six months after the diagnosis was made. Twenty-two patients (16%) with bacterial endocarditis had operation, and six died in hospital. All six patients with fungal endocarditis required vale replacement, and one died in hospital. Uncontrolled or progressive heart failure was the indication for operation in all patients with bacterial endocarditis. When severe heart failure was present, 5 of 11 patients with bacterial endocarditis died in hospital, and only 1 of 3 patients with associated bacteremia survived. If blood cultures were sterile, the duration of preoperative antibiotic therapy did not correlate with hospital survival. None of the patients with bacterial endocarditis developed prosthetic infections, but two developed paravalvular leak.

Massive emboli or persistent mycotic septicemia were the indications for valve replacement in patients with fungal endocarditis. Viable organisms were cultured from the excised valves in all of these patients in spite of preoperative amphotericin B for 30 to 140 days and negative blood cultures. Excision of the infected valve cured the infection in all patients.

Five patients died 6 weeks to 36 months after operation. At the present time 16 patients remain alive 14 to 47 months after operation. Six of nine drug addicts are alive 15 to 27 months postoperatively.
Spironolactone as a Nonspecific Treatment for Primary Aldosteronism
Authors: BRAVO EMMANUEL L. , DUSTAN HARRIET P. , TARAZI ROBERT C.
Published: June 2012

Studies were carried out in 14 patients with primary aldosteronism (1°A) to examine the mechanism(s) by which spironolactone reduces arterial pressure. Measures that produced salt and water depletion were found to consistently reduce arterial pressure. Plasma volume and arterial pressure correlated directly and significantly,
r
= +0.509 (
P
< 0.001), whether pressure was reduced by spironolactone alone or combined with either hydrochlorothiazide or low dietary sodium, or by rapid sodium depletion alone. With small doses of spironolactone, restricting or liberalizing dietary sodium was associated with decreases or increases, respectively, in arterial pressure and plasma volume.

These results suggest 1) that the antihypertensive action of spironolactone is nonspecific and largely dependent on salt and water balance and 2) that maintenance of reduced plasma volume or extracellular fluid volume (ECFV) is a basic component of the pressure response of 1°A to spironolactone therapy.
Diagnosis of Aortic Root Dissection by Echocardiography
Authors: NANDA NAVIN C. , GRAMIAK RAYMOND , SHAH PRAVIN M.
Published: June 2012

Six patients with aortic root dissection confirmed by angiography, surgery, or autopsy were studied by echocardiography. All showed marked parallel widening of the anterior (16 to 21 mm) and/or posterior (10 to 13 mm) aortic walls together with enlargement of the aortic root image. (Normal mean aortic wall thickness 5.7 mm,
sd
1.2; aortic valve disease patients 6.7 mm,
sd
1.5.) In five patients slender aortic valve cusps were recorded moving to the periphery of the inner lumen in systole and not extending to the outer lumen. This finding is useful in excluding calcification of the aortic valve which may produce confusing multiple echoes within the aortic root. Two patients showed 8 to 20 mm variations in the width of the aortic image with slight change in the direction of the transducer indicating that the dissecting hematoma was not uniform in thickness. Other associated findings on the echogram seen in three patients included the demonstration of pericardial fluid collection and mitral diastolic flutter suggestive of aortic regurgitation. Demonstration of enlargement of the aortic root with marked parallel widening of anterior and/or posterior walls appears to be specific for aortic root involvement in dissecting aneurysm of the aorta.
Pathophysiology of Cardiogenic Shock
Authors: ALONSO DANIEL R. , SCHEIDT STEPHEN , POST MARTIN , KILLIP THOMAS
Published: June 2012

Clinical and pathologic data were correlated in 22 patients with cardiogenic shock and 10 "control" patients who died suddenly after infarction without shock. A pathologic technique of ventricular mapping allowed quantification of recent as well as old infarction. Total left ventricular (LV) damage averaged 51% (range 35-68%) in the shock patients and 23% (range 14-31%) in the control group. Shock was associated with recent infarction (all 22 patients), old infarction (21 patients) and extension of infarction (18 patients). Extension, often in a subepicardial manner, averaged 6% of LV mass (range 3-10%) in 18 patients with shock; it preceded shock in four, coincided with the onset of shock in six, and followed shock in seven patients with shock. In contrast, small extensions averaging 2% of LV mass were found in three, and multiple recent infarctions in two control patients. Although progressive myocardial damage was a common pathologic finding, it was infrequently recognized clinically. The electrocardiogram reflected evidence of recent infarction in 56%, old infarction in 31%, and extension in only 30% of patients. These data suggest that appropriate early therapeutic intervention might limit myocardial damage by preventing extension or reinfarction. Since shock was best correlated with total LV damage, such limitation of infarction might reduce the incidence and mortality of cardiogenic shock.
Arrival of Excitation at the Right Ventricular Apical Endocardium in Wolff-Parkinson-White Syndrome Type B
Authors: BEFELER BENJAMIN , CASTELLANOS AGUSTIN , CASTILLO CESAR A. , AGHA ABDUL S. , VAGUEIRO M. CELESTE , MYERBURG ROBERT J.
Published: June 2012

His bundle and bipolar right ventricular apex (RVA) and right ventricular outflow tract (RVOT) catheter electrograms taken from sites 1 mm apart were recorded simultaneously with various surface leads in two patients with Wolff-Parkinson-White syndrome (WPW) type B. In "fusion" beats the presence of a normal H-RVA interval indicated that the apex of the right ventricle was activated by the impulse emerging from the right branch. On the other hand, a shorter-than-normal H-RVA interval implied that the RVA was depolarized by the activation front propagating from the pre-excited site. When this occurred, the V-RVA intervals gave a rough estimate of conduction time from pre-excited area to RVA. The values obtained (40 and 50 msec, respectively) were shorter than in two other patients with WPW type A.

The arrival of excitation patterns in the right ventricular endocardium were similar in WPW type B and in beats produced by RVA stimulation but differed markedly from that of left anterior hemiblock even when the surface electrocardiographic leads showed abnormal left axis deviation in all instances. This resemblance between ventricular complexes attributed to WPW type B and those resulting from stimulation of an inferior (apical) site suggests, but does not prove, that the impulses propagated from an equivalent region of the right ventricle. These simultaneously recorded His bundle and right ventricular endocardial electrograms during electrical stimulation of the heart have increased our knowledge of Wolff-Parkinson-White syndrome.
Sleep and Ventricular Premature Beats
Authors: LOWN BERNARD , TYKOCINSKI MARK , GARFEIN ANDRE , BROOKS PHILLIP
Published: June 2012

Sixty-nine 24-hour electrocardiographic monitoring sessions were conducted in 54 ambulatory subjects. Thirty-one had coronary heart disease (CHD); 11 had miscellaneous heart ailments; and 12 were free of any heart disease. Monitoring was accomplished with a miniaturized cassette recorder and ventricular premature beats (VPBs) were analyzed as to incidence and grade. The occurrence of VPBs during sleep hours was compared to the awake state.

In 22 patients, the incidence of VPBs was reduced by at least 50% during sleep. An additional 13 patients showed a reduction of 25 to 50%. If patients free of ectopic activity during 24-hour monitoring sessions are excluded from analysis, then in 35 of 45 patients, or in 78%, sleep was associated with a lowered occurrence of ventricular extrasystoles. During sleep the VPB grade was likewise lowered. Thus the mean grade for 45 patients changed from 2.75 while awake to 1.78 while asleep. It is of interest that in a number of these patients, trials of various antiarrhythmic drugs were less effective than sleep in reducing the incidence and grade of VPBs. It is concluded that treatment of sporadically occurring ventricular ectopic activity in some patients may require attention to the neurophysiologic trigger rather than the cardiac target.
Left Ventricular Pressure-Volume Relationships During Myocardial Ischemia in Man
Authors: McCANS JOHN L. , PARKER JOHN O.
Published: June 2012

It has been shown in man that myocardial ischemia, whether precipitated by exercise or pacing-induced tachycardia, is associated with abnormalities of left ventricular end-diastolic pressure. There has been controversy as to whether this relationship is due to decreased myocardial compliance or to an increase in left ventricular volume as a manifestation of left ventricular failure. Simultaneous measurements of left ventricular pressure and left ventricular volume using ultrasonic techniques were carried out in five normal subjects and 21 patients with coronary artery disease. In the normal subjects a decrease in left ventricular end-diastolic pressure during pacing was associated with a decrease in left ventricular end-diastolic volume, and during interruption of pacing, pressures and volumes returned to normal. In nine patients with coronary artery disease who did not develop angina, a similar response was seen. In 12 patients with coronary artery disease who developed angina during pacing, the reduction in left ventricular end-diastolic volume during pacing was less marked than the other groups and during periods of interruption the increase in diastolic pressure to 26 mm Hg was accompanied by an increase in left ventricular end-diastolic volume to 24% above control values. The end-systolic volume showed a similar increase during myocardial ischemia.

These data suggest that the changes in left ventricular filling pressure seen during myocardial ischemia are related to increase in left ventricular volume but do not exclude the possibility that there may be accompanying changes in left ventricular diastolic compliance.
Chronic Hemolysis Following Mitral Valve Replacement
Authors: DONNELLY R. J. , RAHMAN A. N. , MANOHITHARAJAH S. M. , DEVERALL P. B. , WATSON D. A.
Published: June 2012

The incidence and severity of chronic intravascular hemolysis was evaluated in a total of 41 patients following mitral valve replacement. Valve replacement was with a gamma-radiated frame-mounted aortic homograft in 21 patients and with a composite seat Starr-Edwards prosthesis, model 6310 or 6320, in 20 patients. The parameters used to assess hemolysis were hemoglobin, hematocrit, reticulocyte count, red cell fragment count, serum haptoglobin, LDH and HBD, hemosiderin in the urine and red cell survival. The degree of hemolysis was classified as mild, moderate or severe. In the prosthetic valve group 85% showed evidence of chronic intravascular hemolysis, of which a third were mild and the rest moderate. The homograft patients did not show any comparable evidence of hemolysis. Statistical analysis of the comparative figures of the parameters used to assess hemolysis in the two groups of patients revealed a significant difference (
P
< 0.01) in hemoglobin and hematocrit and a highly significant difference (
P
< .001) in serum haptoglobins, hemosiderin in the urine, LDH, reticulocyte count, red cell fragment count and red cell survivals.
Venous Thromboembolism and Other Venous Disease in the Tecumseh Community Health Study
Authors: COON WILLIAM W. , WILLIS PARK W. , KELLER JACOB B.
Published: June 2012

The prevalence and incidence of venous thromboembolism and other venous disease has been determined as part of a longitudinal study of health and disease in a Michigan community. When these data are extrapolated to 1970 U.S. census figures, a rough estimate of annual incidence of clinically recognized deep venous thrombosis is over 250,000 cases while that of superficial thrombophlebitis is over 123,000. An estimated 24 million US citizens have "significant" varicose veins while 6 to 7 million have stasis changes in the skin of the legs and 400,000 to 500,000 have or have had a varicose ulcer. The relatively high frequency of these conditions in the adult population of Tecumseh, Michigan, indicates that they represent several of the more common medical problems encountered by the practicing physician.
Postoperative Assessment of Patients with Ventricular Septal Defect and Pulmonary Hypertension
Authors: MARON BARRY J. , REDWOOD DAVID R. , HIRSHFELD JOHN W. , GOLDSTEIN ROBERT E. , MORROW ANDREW G. , EPSTEIN STEPHEN E.
Published: June 2012

Circulatory function of patients with operatively closed ventricular septal defect and preoperative pulmonary arterial hypertension was evaluated in 11 asymptomatic subjects at rest and during intense treadmill exercise three to 15 years after operation. The pulmonary-to-systemic resistance ratio was normal or mildly to moderately elevated preoperatively. Postoperative mean pulmonary arterial pressure at the time of study was normal or mildly elevated at rest in 10 patients and moderately elevated in one (40 mm Hg). During intense upright exercise sufficient to lower pulmonary arterial oxygen saturation to 30%, cardiac output was below the normal range in five patients. Each of these patients had been operated upon after 10 years of age. The magnitude of the postoperative abnormality in cardiac output response to exercise was directly related to age at operation. Two of the five patients with impaired cardiac output response and two other patients manifested an abnormally elevated mean pulmonary arterial pressure during intense exercise. There was a positive correlation between pulmonary arterial pressure during intense exercise and age at operation. These results indicate that late postoperative cardiovascular function may be abnormal in patients with ventricular septal defect and preoperative pulmonary arterial hypertension, and that these abnormalities appear to be related to age at operation. Since all patients were asymptomatic, the long-term clinical significance of these hemodynamic abnormalities remains to be determined.
Left Ventricular Wall Motion Assessed by Using Fixed External Reference Systems
Authors: CHAITMAN BERNARD R. , BRISTOW J. DAVID , RAHIMTOOLA SHAHBUDIN H.
Published: June 2012

Of two methods utilized to assess ventricular wall motion, one (method A) assumes the left ventricular wall moves symmetrically during contraction toward the approximate geometric center of the left ventricle. The other (method B) assumes the left ventricular wall moves symmetrically toward the base of the heart. Clearly, both methods cannot be correct in all patients. We are presenting a method (R) which utilizes two external markers and the diaphragm as an internal marker to evaluate left ventricular contraction pattern.

Of 44 patients studied, the diaphragm moved in four and ventricular wall motion could not be assessed. Fifteen patients had valvular heart disease; six were normal. Findings in method R corresponded to those determined by method B in five of eight patients (63%) with left ventricular hypertrophy and by method A in eight of 13 patients (62%) without left ventricular hypertrophy. This difference was significant (
P
< 0.05). The remaining 19 patients had coronary artery disease; twelve of them had a previous myocardial infarction. In the latter, method R detected an area of asynergy (akinesis or dyskinesis) at ventriculography in ten of 12 patients (84%). The area of asynergy corresponded to the site of infarction determined by electrocardiogram in all patients. Methods A and B detected asynergy in only five of 12 patients (42%) and six of 12 patients (50%), respectively. Using two fixed external reference points and the diaphragm as an internal marker, a better evaluation of left ventricular wall motion can be obtained.
Primary Total Correction of Tetralogy of Fallot in Children Less Than Four Years of Age
Authors: PACIFICO ALBERT D. , BARGERON L. M. , KIRKLIN JOHN W.
Published: June 2012

Twenty-two consecutive severely symptomatic infants and small children less than 4 years of age (mean age 25.5 months, range 3½ to 48 months) have presented for initial surgical treatment of the tetralogy of Fallot at the University of Alabama Medical Center between September 1, 1971 and January 31, 1973. One was considered unsuitable for complete repair because of massive thrombosis of the inferior vena cava, and was successfully treated by a right Blalock-Taus-sig operation. Twenty-one were treated by primary intracardiac repair. One patient (age 24 months) died, a hospital mortality rate of 4.8%. Mean value for the RV/LV peak pressure ratio immediately after repair was 0.55. An outflow patch was placed across the valve ring in one patient, and should have been placed in one other. Heart block has not occurred. Profound hypothermia and circulatory arrest (Kyoto-Barratt-Boyes technique) was used in 9 patients, and cardiopulmonary bypass with profound hypothermia in 12. We discuss the controversy concerning initial management of infants and small children severely symptomatic from the tetralogy of Fallot, and conclude that primary intracardiac repair is advisable in centers prepared for infant intracardiac surgery.
Effect of Propranolol on Myocardial Oxygen Consumption and Its Hemodynamic Correlates during Upright Exercise
Authors: JORGENSEN CHARLES R. , WANG KYUHYUN , WANG YANG , GOBEL FREDARICK L. , NELSON RICHARD R. , TAYLOR HENRY , Gams Frank R. , Vilandre John E.
Published: June 2012

Measurements were made of heart rate, aortic blood pressure, systolic ejection period/beat, myocardial blood flow, and myocardial oxygen consumption in nine normal young men during three bouts of upright bicycle exercise: 1) at the workload which produced a heart rate of 120 beats/minute, 2) at the higher workload necessary to produce a heart rate of 120 beats/minute after administration of intravenous propranolol 0.25 mg/kg, and 3) with infusion of propranolol, at the same workload as the first exercise bout. Comparing exercises 1 and 2, we found a much higher workload was required to produce the same heart rate after propranolol. The blood pressure, heart rate-blood pressure product, and myocardial oxygen consumption were the same despite the much greater level of exertion. Comparing exercises 1 and 3, the heart rate, blood pressure, heart rate-blood pressure product, and myocardial oxygen consumption were all significantly lower during exercise 3 after propranolol despite the fact that the same degree of exercise was being done. As in previous studies, the heart rate-blood pressure product was an excellent correlate of myocardial oxygen consumption despite the change in contractility induced by propranolol. The systolic ejection period was prolonged significantly altering the tension-time index (TTI), which became an inadequate index of myocardial oxygen consumption. It is concluded that the heart rate-blood pressure product is a good index of myocardial metabolic needs during exercise and the relationship is undistorted by marked changes in contractility, but the tension-time index is a poor correlate. This data emphasizes the fact that the relative metabolic loads for the whole body and for the heart are determined separately and may not change in parallel with a given intervention.