bluuebunny/crossref_metadata_2025 huggingface dataset:
Significance of the Initial R Wave in Lead aV
R
of the Electrocardiogram in the Diagnosis of Myocardial Infarction
Authors: OKAMOTO NOBORU , SIMONSON ERNST , AHUJA SURAJ , MANNING GEORGE
Published: June 2012

Distribution, means, and standard deviations of the initial R wave in lead aV
R
of the electrocardiogram are investigated in 1,563 healthy U.S.A., Canadian, and Japanese men, ages 18 to 60 years, and on 448 healthy U.S.A., Canadian, and Japanese women, ages 17 to 51 years, and in samples of cardiac pathology.

Findings in the normal group included an initial R wave in about 50% of the group, no significant effect of age, sex, or race on the mean initial R-wave amplitude in lead aV
R
or its distribution, or on the upper 98% normal limit of the initial R wave, a decrease of the mean R amplitude in aV
R
with clockwise rotation of the transitional zone, and a highly significant correlation of R amplitude in aV
R
to that of R in V
1
, Q
3
, and Q in aV
F
, but too low for reliable prediction.

Right ventricular hypertrophy, anterior wall myocardial infarction, and hypertensive heart disease have no effect on the amplitude or prevalence of the initial R in aV
R
. Posterior and anterior plus posterior wall infarction significantly increased amplitude and incidence of the initial R in aV
R
.
Comparison of a Good Orthogonal Lead System and One Additional Chest Lead with the Conventional 12-Lead Electrocardiogram
Authors: TANNENBAUM OSCAR , VESELL HARRY , SCHACK JEROME A.
Published: June 2012

In a study of the McFee-Parungao system of orthogonal lead electrocardiography 452 electrocardiograms were recorded on 111 normal subjects and 201 patients with cardiovascular disease and abnormalities in the conventional 12-lead electrocardiogram. Comparison of the two lead systems and evaluation of criteria for the electrocardiographic diagnosis of normal, right ventricular hypertrophy, left ventricular hypertrophy, right and left bundle-branch block, and several types of myocardial infarction revealed good correspondence between the two systems. Because of deficient representation of the precordial midzone potential, a preferential unipolar lead resembling lead V
4
was introduced. This ancillary lead contributed important information to the electrocardiographic diagnosis of localized apical myocardial infarction and also indicated ventricular hypertrophy in cases in which it was not evident in the three orthogonal leads.
Studies with Tritiated Digoxin in Anephric Human Subjects
Authors: DOHERTY JAMES E. , FLANIGAN WILLIAM J. , PERKINS WILLIAM H. , ACKERMAN GEORGE L. , Gammill Jacquelyn , Sherwood Joyce
Published: June 2012

Tritiated digoxin was given to 11 patients when anephric prior to renal transplant. These patients exhibited high digoxin serum levels, increased digoxin serum half-times, and reduced excretion of digoxin compared to those of patients with congestive heart failure and normal BUN and are similar in this respect to patients with severe compromise of renal function. The stool excretion of digoxin is increased in anephric patients, but this does not compensate for the lack of renal excretion of digoxin. These findings indicate the need for prudent administration of digoxin to anephric patients, as well as those with renal failure. Often the dose of digoxin may be reduced as much as one third to one half of the usual maintenance dose.
Parasystole with Fixed Coupling
Authors: LANGENDORF RICHARD , PICK ALFRED
Published: June 2012

Four examples of spontaneous and six of artificial ventricular parasystole exhibiting fixed coupling of the premature beats were presented. In five cases, one of the pacemakers was located in the S-A node, in four in the A-V junction, and in one at first in the A-V junction and later in the ventricles. The material was divided according to the presence either of mutual protection of the two pacemakers (group I, four cases) or of unilateral protection of the parasystolic pacemaker (group II, five cases).

When the rates of both pacemakers are regular and the conditions for impulse propagation remain stable, fixed (forced) coupling of parasystolic beats develops under the following conditions: in group I (with mutual protection) (a) if there is-by chance or by experimental adjustment-a simple numerical relation between the two pacemaker rates, or (b) if subthreshold stimuli become effective only during a short super-normal period of excitability in the early portion of the ventricular cycle; and in group II (with unilateral protection) as a result of a fixed relationship that develops secondarily to the discharge of the dominant pacemaker by the parasystolic pacemaker, a mechanism referred to as "reversed coupling." This mechanism may be combined with that of group Ib.
Persistence of Reflex Sympathetic Nervous System Activity in Man on Guanethidine or Reserpine
Authors: COFFMAN JAY D.
Published: June 2012

The effect of guanethidine and reserpine on the reflex sympathetic nervous system vasoconstriction in the calf and foot induced by a prolonged, generalized stimulus (body cooling for 1 hour) was studied in 12 normal subjects. Large daily clinical-doses of guanethidine (40 to 60 mg) or reserpine (1 mg) were given orally for 2 and 3 weeks, respectively. Foot and calf blood flows were measured by venous-occlusion, water plethysmography. Two control studies were performed on each subject, one before and another long after administration of the drug; body cooling produced significant decrease in calf and foot blood flow and increases in vascular resistance in both control studies. Subjects evidenced drug effects by a significant decrease in pulse rate, postural hypotension, hypotension following exercise, and blockade or attenuation of the Valsalva maneuver "overshoot." The attenuation of the sympathetic nervous-system vasoconstrictor reflex to general body cooling was not statistically significant.

Since large clinical doses of reserpine or guanethidine administered for 3 or 2 weeks, respectively, did not inhibit the reflex sympathetic vasoconstrictor effect of total body cooling, functional sympathetic neurotransmitter substance cannot be said to be absent.
Ultrasonic Diagnosis of Pericardial Effusion
Authors: ROTHMAN JEFFREY , CHASE NORMAN E. , KRICHEFF IRVIN I. , MAYORAL RAFAEL , BERANBAUM ELLIOTT R.
Published: June 2012

This study was undertaken to establish a method for diagnosing pericardial effusions quickly, simply, and accurately without danger to the patient. Ultrasound examination that was used in this study employed the B mode (cross-sectional representation) in which the vertical deflections of the A scan are turned on end and make a line of dots on the cathode ray tube. These, at the appropriate time, outline the anatomy including moving structures which are seen as wavy lines in the final picture and on the fluorescent oscilloscopic screen. Forty-three patients, 23 suspected of having pericardial effusion, were studied. The diagnosis usually was made on posterior examination and confirmed on anterior examination. Cardio-echograms are shown to provide an accurate, quick, simple method of diagnosing pericardial effusion that is accurate for use in estimating the size of the large effusions.
Intracardiac Pressure-Flow Dynamics in Isolated Ventricular Septal Defects
Authors: LEVIN AARON R. , SPACH MADISON S. , CANENT RAMON V. , BOINEAU JOHN P. , CAPP M. PAUL , JAIN VISHNU , BARR ROGER C.
Published: June 2012

This study was conducted to determine the nature of intracardiac shunting in 50 patients between the ages of 3 and 15 years with isolated ventricular septal defects. Simultaneous right and left ventricular pressures and biplane cineangiocardiography were utilized to study the timing and the direction of flow across the defect. Patients with low to moderately elevated right ventricular pressures demonstrated left-to-right shunting across the defect throughout the cardiac cycle. When pressure in the right ventricle approximated that of the left, right-to-left shunting occurred across the defect into the left ventricle during isovolumic relaxation. All patients shared in common the following: (1) a predominant left-to-right gradient and shunt across the defect into the body of the right ventricle during diastole; and, (2) augmentation of the left-to-right gradient with resultant increase of the shunt into the right ventricle during isovolumic contraction immediately preceding opening of the aortic valve.

In comparing patients with and without pulmonary hypertension, the major variations in the cardiac cycle occurred during the periods of ventricular ejection and isovolumic relaxation. These two periods are primarily affected by the changing relationships of the size of the defect, ratio of pulmonary to systemic resistance, and magnitude of net shunts.
SPECIAL ARTICLE
Authors: SCHROEDER HENRY A.
Published: June 2012

Observations made in the last 15 years by the author and others concerning the effect of trace metals, particularly cadmium and chromium, on animals and man are reviewed with special reference to hypertension and atherosclerosis. These trace metals come from the soil or sea. Among the topics covered are cadmium hypertension in rats, diabetes mellitus and chromium deficiency, deficiency sources, and possible losses of chromium, and the influence of drinking water on death rates from atherosclerosis. The conclusions are that one common form of hypertension is probably an example of accumulation of cadmium in the kidney and that deficiency of chromium may influence glucose and lipid metabolism and affect atherosclerosis. Other trace elements may contribute also.
Chronic Primary Chylopericardium
Authors: FAWAL ISA A. , KIRKLAND LARRY , DYKES RONALD , FOSTER GLENN L.
Published: June 2012

The case of a 36-year-old white man who had recurrent milky pericardial effusion and repeated pericardiocenteses over a period of 1 year with minimal disability or symptoms is presented. Surgical management included thoracotomy with ligation of all structures resembling lymphatic channels in the chest in several places and hemipericardiectomy. Neither the source of chyle in the pericardium nor the etiological agent of this condition could be found. Criteria for successful management of this condition are re-emphasized.
Gaucher's Disease of the Lung Causing Severe Pulmonary Hypertension with Associated Acute Recurrent Pericarditis
Authors: ROBERTS WILLIAM C. , FREDRICKSON DONALD S.
Published: June 2012

The clinical and pathological features of a 30-year-old man with Gaucher's disease are described. He had severe pulmonary hypertension resulting from obstruction of pulmonary capillaries by Gaucher cells. Acute recurrent pericarditis of unknown etiology terminally led to hemopericardium and cardiac tamponade.
Correction of Total Anomalous Pulmonary Venous Drainage in Infancy Utilizing Deep Hypothermia with Total Circulatory Arrest
Authors: DILLARD DAVID H. , MOHRI HITOSHI , HESSEL EUGENE A. , ANDERSON HOWARD N. , NELSON RONALD J. , CRAWFORD EDWARD W. , MORGAN BEVERLY C. , WINTERSCHEID LOREN C. , MERENDINO K. ALVIN
Published: June 2012

Four critically ill infants aged 3, 5, 5, and 13 months; weighing 3.7, 4.6, 5.3, and 6.5 kg, respectively; with total anomalous pulmonary venous drainage, underwent complete correction of their lesions with the utilization of surface-induced deep hypothermia. Although this series is small, we are not aware of any other consecutive series in this age group with a comparable mortality rate. Rectal temperatures of 17.5 to 20.2 C were utilized, with periods of cardiac arrest and total circulatory interruption of 32 to 41 minutes. Important aspects of the technique are surface cooling, deep ether anesthesia, intravenous low-molecular-weight dextran, induced respiratory alkalosis during cooling, and electrical pacing during resuscitation. This method works well in the infant, in contrast with perfusion techniques in which surgical mortality is excessively high.
Surgical Treatment of Cardiac Defects Associated with Corrected Transposition of the Great Vessels
Authors: HALLMAN GRADY L. , GILL SARJIT S. , BLOODWELL ROBERT D. , MCNAMARA DAN G. , LATSON JOSEPH R. , LEACHMAN ROBERT D. , COOLEY DENTON A.
Published: June 2012

Corrected transposition of the great vessels is characterized by transposition of the aorta in front and to the left of the pulmonary artery and inversion of the ventricles and atrioventricular valves. Unless it is associated with an intracardiac defect, the circulation of blood inside the heart is normal, and the anomaly may not be recognized clinically. The altered anatomy requires important modifications in the technical features of operative correction of associated cardiac defects.

Among 53 patients with corrected transposition of the great vessels, 31 underwent operation for associated intracardiac defects. These were ventricular septal defects (11 patients), tetralogy of Fallot (seven), common ventricle (five), single ventricle (three), tetralogy of Fallot with pulmonary atresia (two), pulmonary stenosis (one), pulmonary atresia (one), and tetralogy of Fallot with common ventricle (one).

Postoperative complete heart block, which usually leads to a fatal outcome, may follow closure of ventricular septal defect when conventional techniques are used. Although only one death from heart block occurred in seven patients operated on through a right ventriculotomy, we have employed left ventriculotomy in the last two patients to reduce the risk of heart block and to afford better exposure of the ventricular septal defect. The presence of preoperative complete heart block does not contraindicate correction of associated defects, but consideration should be given to insertion of a pacemaker at the time the lesion is corrected since these patients are likely to have Stokes-Adams attacks later.

The anatomical features of associated common ventricle, single ventricle, and tetralogy of Fallot present such severe technical problems that complete correction of these anomalies is accompanied by a high risk. Total correction of tetralogy of Fallot was successfully carried out in only one of seven patients. Others were treated by some form of systemic-pulmonary shunt with good results. Two patients with tetralogy of Fallot and pulmonary atresia and one patient with pulmonary atresia were also treated by systemic-pulmonary shunts and obtained satisfactory palliation. One patient with pulmonary stenosis underwent successful transventricular pulmonary valvulotomy. A ventricular septum was created in five patients with common ventricle. There were only two survivors; the other three died of complete heart block.

Recognition of corrected transposition of the great vessels associated with an intracardiac defect that requires operative repair is important because of technical problems that the morphological alterations of ventricular inversion impose.
Pulmonary Compliance Following Open-Heart Surgery and Its Relationship to Ventilation and Gas Exchange
Authors: ELLISON LOIS T. , DUKE JOHN F. , ELLISON ROBERT G.
Published: June 2012

Pulmonary function was studied preoperatively and postoperatively in 71 patients undergoing 41 open-heart operations, ten thoracic operations not requiring cardiopulmonary bypass, ten intra-abdominal, and ten peripheral procedures. After operation total respiratory compliance was significantly reduced below the preoperative value for ten days in the open-heart group. Decreases of lesser degree and of shorter duration were noted in the thoracic and intra-abdominal patients with no significant reduction in the peripheral cases. Tidal volume decreased proportionately to the decrease in compliance, and respiratory rate increased, while total ventilation usually remained the same or was slightly increased. Oxygen uptake was significantly increased after open-heart operations, and there was a significant negative correlation between oxygen uptake and compliance. Abnormal venous admixture, not corrected by oxygen inhalation, was observed after cardiopulmonary bypass with a return to preoperative level coinciding with that of compliance. Cardiac output did not correlate with any other measurement.

The data suggest that the postoperative breathing pattern after open-heart surgery is a compensatory adjustment to decreased compliance and that reduced compliance is one of the causes of the increased work of breathing and oxygen demands after open-heart surgery.
SPECIAL ARTICLE
Authors: DEHAAN ROBERT L.
Published: June 2012

It is no longer necessary to guess at why embryonic malformations occur. Techniques are now available to test almost any hypothesis concerning developmental phenomena. These include the entire armamentarium of modern cell biology: organ and tissue culture, microsurgery, time-lapse cinematography, autoradiography, and many other related methodologies. The developmental events which lead to the formation of a functional heart in the early embryo can be analyzed with these techniques. Of the pertinent questions concerning developmental processes related to congenital heart disease, those of dextrocardia and differential growth, ventricular septal defects, and cell migration and adhesion in cardiogenesis are discussed. Several experimental systems useful for attacking these questions are described. Relative growth of specific segments of the primitive tubular heart contributed by the right and left wings of the cardiogenic crescent has been examined to elucidate the mechanism of dextral looping of the tube. Migration of precardiac cells to form the heart has been traced with cinematography in the intact embryo, and by following movements of cells labeled in situ with tritium using autoradiographic techniques. To analyze the mechanisms of guidance of such cells, endoderm plus adherent precardiac mesoderm can be explanted and manipulated in tissue culture.
Amelioration of Angina Pectoris in Idiopathic Hypertrophic Subaortic Stenosis with Beta-Adrenergic Blockade
Authors: COHEN LAWRENCE S. , BRAUNWALD EUGENE
Published: June 2012

Beta-adrenergic receptor blockade has been demonstrated to reduce obstruction of the left ventricular outflow tract in patients with idiopathic hypertrophic subaortic stenosis (IHSS) and has also proved helpful in reducing angina pectoris due to ischemic heart disease. Accordingly, the effects of oral propranolol on the level and duration of exercise required to produce angina in seven patients with IHSS were compared with a placebo. Improvement in exercise performance was observed in six patients taking propranolol orally in doses ranging from 80 mg to 480 mg daily. Clinical improvement was sustained in the four patients given propranolol since discharge from the hospital for periods up to 15 months, and in three it has been possible to obviate corrective operations. The mechanism by which propranolol is efficacious in this disease is probably related to the diminution of myocardial O
2
requirements resulting from the reduction of wall tension, velocity of contraction, and heart rate induced by beta-adrenergic receptor blockade.
Percentage of Left Ventricular Stroke Work Loss
Authors: TOBIN JOHN R. , RAHIMTOOLA SHAHBUDIN H. , BLUNDELL PETER E. , SWAN H. J. C.
Published: June 2012

The ratio of the mean systolic transaortic valvular gradient to the mean systolic left ventricular pressure times 100 yields a percentage that represents the portion of left ventricular pressure-volume work per stroke lost because of outflow-tract obstruction. The percentage of the left ventricular stroke work loss and the area of the aortic orifice have been estimated in 49 patients with aortic valvular stenosis and two open-chest dogs with varying degrees of supravalvular aortic constriction. Left ventricular stroke work loss of 30% or greater was associated with calculated aortic valve areas of 1.0 cm
2
(or 0.60 cm
2
/m
2
) or less. These values are representative of serious obstruction to left ventricular outflow, that is, approximately 75% or greater reduction of normal orifice size. The calculation of the percentage of left ventricular stroke work loss, besides being simple, is based upon the most reliable measurements obtainable at left heart catheterization, that of the pressure pulses.
Long-Term Reduction of Serum Cholesterol Levels of Patients with Atherosclerosis by Small Doses of Neomycin
Authors: SAMUEL PAUL , HOLTZMAN CHARLES M. , GOLDSTEIN JANE
Published: June 2012

The effect and tolerance of long-term oral administration of small doses of neomycin as a serum cholesterol reducing agent has been investigated. Sixteen patients were given neomycin sulfate orally for periods varying from 12 to 40.1 months, following control periods of 2.6 to 14.6 months. After an initial daily dose of 2 g of neomycin, the daily dose was varied between 0.5 and 2 g according to response. Average total serum cholesterol concentrations decreased in each of the 16 patients by 15 to 32%; the average decrease for the group was 22%. The difference was statistically significant in each patient at the 0.1% level. Serum cholesterol concentrations were maintained at the lower plateau as long as the drug was given. In an additional patient, after administration of neomycin for 2 months there was no change in serum cholesterol concentrations and the study was discontinued. Another developed severe diarrhea, nausea, and abdominal cramps during the first week of the study, so that medication was interrupted. No other serious side effects occurred. During the first 2 weeks of medication eight of the 16 patients experienced mild diarrhea or abdominal cramps or both which subsided spontaneously during continued medication. Physical examinations were carried out, kidney and liver functions remained normal, and pathogens were not grown from stool cultures.
Cholesterol Embolization
Authors: MOLDVEEN-GERONIMUS MIRIAM , MERRIAM JOSEPH C.
Published: June 2012

In the two cases of multiple system disease due to atheromatous embolization presented, increasingly severe hypertension developed owing to renal involvement. One patient had acute pancreatitis from embolization to the pancreas. The second patient had mottling of the skin of the legs. Purple toes were present and gangrene developed in 3 toes. The possible influence of anticoagulant therapy in promoting peripheral cholesterol embolism is discussed. It is suggested that the "purple toe syndrome" may be a manifestation of cholesterol embolization secondary to anticoagulant therapy.
Hemodynamic Responses to Graded Treadmill Exercise in Young Untreated Labile Hypertensive Patients
Authors: LEVY ARTHUR M. , TABAKIN BURTON S. , HANSON JOHN S.
Published: June 2012

Twenty labile hypertensive patients and their age-matched controls were studied at rest and during five levels of treadmill exercise. Intra-arterial blood pressure, cardiac output, and various aspects of the pressure pulse wave were analyzed under these conditions. Exercise provoked diastolic hypertension in 30% of the patient group. Mean group pressure responses demonstrated an almost constant differential through all phases of the study. The validity of a previously suggested classification of labile hypertensive subjects based on resting cardiac output estimations is questioned. A differentiation of modes of adjustment to an increased pressure load was suggested from exercise measurements of arterial ejection time. Despite numerous factors affecting the measurement, first derivative of the peripheral arterial pulse correlated well with indices of ejection time and mean rate of left ventricular ejection.
Hemodynamic Studies in Cardiogenic Shock
Authors: SMITH H. J. , ORIOL A. , MORCH J. , MCGREGOR M.
Published: June 2012

In 14 subjects with severe cardiogenic shock the characteristic findings before treatment were hypotension, low cardiac output, and increased central venous pressure, with normal values for total peripheral resistance. Oliguria, lactic acidosis, hypocapnia, and hypoxemia also were present. These changes were interpreted as reflecting acute heart failure in association with a peripheral vascular response which was inadequate to maintain normal blood pressure. Isoproterenol caused a decrease in venous pressure and an increase in cardiac output. In most cases this was sufficient to increase blood pressure, despite slight reductions in peripheral vascular resistance. In a few cases, however, the inotropic effect of the drug was so small that the reduction in vascular resistance caused a further fall in arterial pressure. Metaraminol caused elevation of venous pressure, peripheral resistance, and blood pressure at the expense of some reduction of cardiac output. An approach to therapy is discussed in the light of these findings.
Clinical Sequelae from Arterial Needle Puncture, Cannulation, and Incision
Authors: MORTENSEN JD
Published: June 2012

A study of 3,193 arterial entries of various types disclosed 66 major complications and 321 minor complications for a total complication rate of 13%. The Seldinger technique of percutaneous arterial catheterization was followed by the highest incidence of complications, the percutaneous needle puncture method was associated with an intermediate complication rate, and the cutdown arteriotomy with suture repair resulted in the lowest complication rate. Utilizing the brachial artery as the entry site resulted in a significantly higher complication rate than utilizing other sites for entering the arterial tree did. Factors significantly increasing the risk of arterial entry include the existence of aortic valvular incompetence in the patient, systemic anticoagulation at the time of the arterial entry, and the presence of arteriosclerosis or hypertension in the patient.
Intrapulmonary Segment in Anomalous Pulmonary Venous Connection
Authors: EVERHART FRANCIS J. , KORNS MICHAEL E. , AMPLATZ KURT , EDWARDS JESSE E.
Published: June 2012

Three cases showing a large anomalous venous channel in the right lung are presented. In each case the large vein was a part of a pulmonary venous collateral system in association with anomalous pulmonary venous connection, partial in one case, and total in two. In two of the cases, each of which was an example of total anomalous pulmonary venous connection, the anomalous vein in the right lung received the entire venous system of the left lung. In the two cases with conventional roentgenograms the anomalous vein within the right lung was apparent. Its shape, in some respects, resembled that of the anomalous pulmonary vein in the scimitar syndrome. Selective pulmonary arteriography appears to offer the best means of differentiation between an anomalous vein of the type described here and that of anomalous drainage of the hypoplastic right lung to the inferior vena cava (the scimitar syndrome).
Electrocardiographic Changes in Clinically Normal Older Men Following Near Maximal and Maximal Exercise
Authors: LESTER F. MARTIN , SHEFFIELD L. T. , REEVES T. JOSEPH
Published: June 2012

This study was undertaken to compare the incidence of electrocardiographic abnormalities associated with a near maximal and a maximal exercise test, because of previous reports of high incidence of such abnormalities among older men.

One hundred fourteen male volunteers ranging in age from 40 to 75 years were studied by both near maximal and maximal exercise testing. All subjects were considered normal by history and physical examination. Electrocardiographic responses to exercise testing were monitored by telemetered bipolar leads during and immediately after exercise and by standard electrocardiographic leads made during the recovery period between 30 seconds and 5 minutes after the termination of exercise. Both near maximal and maximal exercise testing were accomplished without significant complication. The incidence of segmental ST depression following the near-maximal test was less than 1%. The incidence of segmental ST depression following the maximal exercise test was 5.2% (6-114). Only one of the five abnormalities detected during or after maximal exercise persisted for more than 30 seconds after the conclusion of exercise. Since such changes occur in a high percentage of patients with heart disease, such changes appear to have a high degree of specificity for some form of cardiac abnormality.
A Comparative Study of Nitroglycerin and Propranolol
Authors: ROBIN ERWIN , COWAN CHARLES , PURI PRITPAL , GANGULY SUNILENDU , DEBOYRIE EMILE , MARTINEZ MILA , STOCK THOMAS , BING RICHARD J.
Published: June 2012

The action of sublingual nitroglycerin (0.6 mg) and intravenous propranolol (0.1 mg/kg) on shortening of right ventricular fibers was investigated in patients with and without coronary artery disease. This was accomplished with a newly devised strain gauge catheter. Hemodynamic parameters and changes in the oxidation-reduction potential of heart muscle were determined. Nitroglycerin results in decrease in shortening and velocity of shortening of ventricular fibers, heart rate, left ventricular end-diastolic and systemic pressure, dp/dt, tension-time index, stroke index, peripheral resistance, and left ventricular minute work in normal and arteriosclerotic subjects. Intravenous propranolol leads to a fall in velocity of shortening of myocardial fibers, heart rate, dp/dt, stroke index, and left ventricular minute work. However, there is an increase in tension-time index and peripheral resistance with no change in systemic pressure. Left ventricular end-diastolic pressure rises significantly in arteriosclerotic patients. The myocardial oxidation-reduction potential increases after nitroglycerin whereas it falls after propranolol in normal and arteriosclerotic patients.
Comparison of the Double Two-Step Test and the Maximal Exercise Treadmill Test
Authors: BELLET SAMUEL , ROMAN LAURIAN
Published: June 2012

A comparison of the double two-step test and a more strenuous type of exercise test was made to assess the value of the latter procedure in increasing the sensitivity of the electrocardiographic exercise test.

In young, normal women, 17 to 20 years of age, who represent a group with minimal chances for significant silent coronary heart disease, both the double two-step test and graded maximal exercise tests were always normal. This is consistent with the view that ischemic electrocardiographic changes are not usually elicited in subjects with normal coronary circulation, even after strenuous exercise.

In middle-aged men and women, 40 to 65 years of age, in whom the possible existence of clinically silent coronary heart disease was suggested by age and other parameters (atypical chest pain, hypertension, or diabetes, or all three), the maximal exercise test on the treadmill, as compared to the double two-step test, increased the yield of positive electrocardiographic results by 12%. These findings suggest that, in selected "coronary-prone" subjects on whom the double two-step test is negative, increasing the amount of exercise might be of value in the evaluation of the exercise test.
Application of Computer Techniques to the Detection and Analysis of Spontaneous P-Wave Variations
Authors: BRODY DANIEL A. , WOOLSEY MELVIN D. , ARZBAECHER ROBERT C. , Phillips Harry A.
Published: June 2012

A small, laboratory-oriented computer, programmed to scan highly amplified electrocardiographic signals in real-time, specifically searches for spontaneous changes in P-wave configuration. The tape-recorded bipolar extremity leads of 71 normal subjects so scanned revealed sustained periods of ectopic atrial beating in 31. There were 18 with a single well-defined ectopic focus, six with double foci, and seven with atrial activity too variable for simple categorization. Random noise was removed from atrial complexes of the classifiable groups by a discriminant procedure which averaged 50 to 100 members of a preselected P-wave family and automatically bypassed all others. The unexpectedly high incidence of variability indicates that normal atrial excitation is commonly an unstable or metastable process. Actual shifts of pacemaker location, variable exit sites from sinoatrial tissue, and preferential conduction pathways through the atria are postulated as possible explanations of the observed behavior. The richly notched configuration of normal P waves suggests that atrial depolarization proceeds through specialized conductive tissue rather than by uniform centrifugal spread.
Pulmonary Air Embolism During Insertion of a Permanent Transvenous Cardiac Pacemaker
Authors: ZEFT HOWARD J. , HARLEY ALEX , WHALEN ROBERT E. , MCINTOSH HENRY D.
Published: June 2012

In two patients pulmonary air embolism was a complication of the implantation of a permanent transvenous cardiac pacemaker. One of these patients, in whom air embolism was documented by cinefluorograms, is described in detail. Cinefluorograms demonstrated air in the right ventricle and main pulmonary artery with clear visualization of the opening and closing of the pulmonary valve. Both patients were treated conservatively by use of the left lateral decubitus position and administration of oxygen. The pathophysiology, hazards, and therapy of this complication are reviewed. Massive pulmonary air embolism is potentially fatal, and special care with regard to insertion of the electrode catheter should be taken in order to prevent it.
Coronary Heart Disease in Women
Authors: MULCAHY RISTÉARD , HICKEY NOEL , MAURER BRIAN
Published: June 2012

One hundred women with classical coronary heart disease were studied in an attempt to identify etiological factors. Three dominant factors were hypertension, cigarette smoking, and hypercholesterolemia. Cigarette smoking and hypertension were present together or separately in 80 to 90% of the patients. Four patients were diabetics; six had grossly abnormal serum cholesterol levels; and there was one case each of associated myxedema, aortic stenosis, and postoperative hypotension. Comments are made about the role of family history, obesity, hypercholesterolemia, abnormal glucose tolerance, exercise and dietary experience, and the influence of the menopause. It is believed that the proper control of hypertension in the population and the elimination of cigarette smoking would cause an appreciable or even dramatic reduction in the incidence of precocious and middle-aged coronary heart disease in women.
Temporary Transvenous Catheter-Electrode Pacing of the Heart
Authors: TANCREDI ROBERT G. , McCALLISTER BEN D. , MANKIN HAROLD T.
Published: June 2012

Experience with 110 separate periods of transvenous cardiac pacing by means of a catheter-electrode in 91 patients has been reviewed. Indications for the use of the catheter-electrode included (1) complete heart block with and without Adams-Stokes syndrome, (2) other arrhythmias with and without cardiogenic syncope, (3) malfunction of previously implanted permanent pacemaker units, and (4) need for pacing during general surgical procedures in patients with a variety of rhythm disturbances. A case illustrating the combined use of drug therapy and catheter-electrode pacing in controlling paroxysmal ventricular tachycardia is presented.

Only six deaths occurred in spite of the serious heart disease in all 91 patients in this series. Two were related to complications of temporary transvenous intracardiac pacing. The major complications associated with the procedure included perforation of the heart, bacteremia, acute myocardial infarction, cephalic vein phlebitis, and ventricular tachyarrhythmia. Minor problems were primarily related to equipment failure or positional difficulties with the catheter-electrode and were usually of no serious consequence.
Effects of Diphenylhydantoin on Atrioventricular Conduction in Man
Authors: HELFANT RICHARD H. , LAU SUN H. , COHEN STAFFORD I. , DAMATO ANTHONY N.
Published: June 2012

The effects of intravenous diphenylhydantoin (5 mg/kg) on atrioventricular conduction in man at controlled heart rates in the digitalized and undigitalized state were studied. In undigitalized subjects, diphenylhydantoin administration consistently decreased A-V conduction time in each individual subject when identical heart rates were compared. Ouabain infusion produced an increase in A-V conduction time and this prolongation was always reversed by diphenylhydantoin. In two patients with atrial flutter and in two with atrial fibrillation, diphenylhydantoin caused a decrease in ventricular rate without affecting the atrial arrhythmias.

These findings are of clinical importance, especially in the therapy of digitalis toxicity. When digitalis excess is manifested by both ectopic beats and incomplete A-V block, diphenylhydantoin would have special utility since, in contrast with the commonly used antiarrhythmic agents, it decreases A-V conduction time in addition to suppressing ectopic beats. Diphenylhydantoin-induced depression of the ventricular rate in atrial flutter or fibrillation may also be useful clinically. However, since diphenylhydantoin markedly decreases ventricular automaticity, its use in patients with complete heart block is contraindicated.
Congenital Cardiac Disease Associated with Polysplenia
Authors: MOLLER JAMES H. , NAKIB AHMAD , ANDERSON RAY C. , EDWARDS JESSE E.
Published: June 2012

The well-recognized association of congenital cardiac disease with asplenia has been termed "bilateral right-sidedness" or dextro-isomerism, since the spleen is absent, the liver is symmetrical, and each lung has three lobes and an epiarterial bronchus. In a study of pathological material from 12 patients with congenital cardiac disease associated with multiple spleens (as contrasted to accessory spleen), we found a definite tendency for the symmetrical development of organs but with a tendency for bilateral left-sidedness or levo-isomerism.

The abnormalities assumed one of three forms as follows: (1) absence of a normal right-sided structure, (2) bilateral organs, each with the structure of a left-sided organ, or (3) excessive tissue of a left-sided organ. Thus, in polysplenia we observed a tendency for (1) absence of the hepatic segment of the inferior vena cava and absence of the gallbladder, (2) two lobes in each lung with hyparterial bronchi, and (3) multiple spleens. Other noncardiac abnormalities were partial or complete abdominal heterotaxia and partial malrotation of the bowel. The cardiac malformations included dextrocardia, bilateral superior venae cavae, anomalous pulmonary venous connection with malposition of the atrial septum, and defects in the atrial septum and in the ventricular septum.

Our study suggests that the developmental complex of multiple spleens is closely related to the asplenic syndrome, with the important difference being left-sided symmetry rather than right-sided symmetry.
Pericardial and Myocardial Disease Associated with Serological Evidence of Infection by Agents of the Psittacosis-Lymphogranuloma Venereum Group (Chlamydiaceae)
Authors: SUTTON GEORGE C. , MORRISSEY RICHARD A. , TOBIN JOHN R. , ANDERSON TRUMAN O. ,   Idiopathic Myocardial Disease Study Group of the Cook County Hospital, Chicago, Illinois.
Published: June 2012

Nine patients with acute pericarditis or myocarditis, or both, were found to have serological evidence of concurrent infection by a psittacosis agent. Three patients had conclusive epidemiological and clinical evidence of complicating pulmonary psittacosis and demonstrated that psittacosis agent does produce inflammatory heart disease in this geographic area.

Six patients had imperfect corroborative evidence of psittacosis and their clinical manifestations were atypical. Indeed, half of these patients were initially believed to have some form of idiopathic myocardial disease. Studies of these patients suggest that psittacotic infection m
ay be causal in certain forms of heart disease commonly designated primary myocardial disease.
Acute Mitral Regurgitation in Man
Authors: BARTLE STUART H. , HERMANN HECTOR J.
Published: June 2012

Four patients are presented who developed acute mitral regurgitation 5 days, 2, 3, and 18 months, respectively, before cardiac catheterization. The hemodynamic findings in the three early cases resemble those found in the presence of a constricting pericardium: left and right ventricular, as well as left and right atrial pressures, equilibrated during diastole. As expected, giant left atrial
v
waves accompanied markedly elevated pulmonary arterial pressures and low cardiac indices. Biplane angiocardiography showed only slight left atrial and moderate left ventricular enlargement, but showed a large regurgitant fraction and dilated pulmonary veins. Orthopnea was transient or absent in two of the three early cases.

The pericardium may play a role in the early phase of acute mitral regurgitation in mimicking signs of right heart failure and preventing pulmonary edema. Development of increased pulmonary venous capacitance may be another major early mechanism of compensation since the pericardium may be preventing left atrial enlargement. Later in the course, after 6 months, the pericardium does not appear to be a factor in the hemodynamics, as noted in our patient and in patients reported by others.
Coronary Heart Disease and Future Expectation of Life
Authors: WALKER ALEXANDER R. P.
Published: June 2012

Mortality from coronary heart disease (CHD) has risen enormously over the last generation. Some regard the concomitant increase in life expectancy as the sole explanation; others maintain the increases at least in part to be real. Irrespective of the true causes, the question arises: If increases in CHD mortality continue in certain of the populations most affected, may not expectation of life ultimately decrease? An answer is sought by examining relevant information (1) on a large community of rural Indians having a low prevalence of CHD, and (2) on the offspring of Indian immigrants to South Africa, whose CHD mortality now exceeds that of the local whites. It is concluded that while promotive factors linked with urbanization and prosperity are chiefly responsible, the bearing of an ethnic propensity cannot be excluded. Continuation of the present CHD mortality trend in South African Indians almost undoubtedly will decrease their life expectancy, which, even at present, appears to compare unfavorably from youth onward with that of the rural Indian group described.
Observations on the Blood Pressure of Tibetans
Authors: SEHGAL A. K. , KRISHAN IQBAL , MALHOTRA R. P. , GUPTA H. D.
Published: June 2012

Observations on the blood pressure of a group of 660 displaced male Tibetans revealed striking dissimilarities in regard to the mean systolic and diastolic figures as compared to those reported for Europeans and Americans. The average Tibetan figures are lower than those of Western populations; however, a comparable variability after the fourth decade and a parallel spread of values with age and weight were found in the Tibetan data. The socioeconomic status and height bore no relation to the blood pressure levels. The results obtained from this survey on the Tibetans are compared with those of other Mongolian groups. It is suggested that the differences of blood pressure among related Mongolian groups and populations studied in the West are largely determined by environment.
Impaired Rate of Left Ventricular Filling in Idiopathic Hypertrophic Subaortic Stenosis and Valvular Aortic Stenosis
Authors: STEWART SCOTT , MASON DEAN T. , BRAUNWALD EUGENE
Published: June 2012

In order to determine whether there is any interference with left atrial emptying or left ventricular filling in idiopathic hypertrophic subaortic stenosis (IHSS) and aortic stenosis, the fall in pressure (y descent) of the left atrial
v
wave following the opening of the mitral valve was analyzed in 27 patients with IHSS and in 22 patients with valvular aortic stenosis, and the results were compared to those for 13 normal subjects and 24 patients with mitral stenosis. The y descent in 0.1 sec and the mean rate of the y descent, as well as the maximum rate of decline, were reduced in all three groups of patients, as compared to those of the normal group. The changes in IHSS were more marked than those occurring in patients with aortic stenosis or mitral stenosis. These findings in patients with IHSS and valvular aortic stenosis appear to result from reduced left ventricular compliance. It is concluded that there is an impairment of left ventricular filling in IHSS and that obstruction to ventricular inflow, as well as to outflow, contributes to the hemodynamic changes in this condition.
Clinical Significance of Coronary Artery Calcification Seen Fluoroscopically with the Image Intensifier
Authors: MCGUIRE JOHNSON , SCHNEIDER HAROLD J. , CHOU TE-CHUAN
Published: June 2012

Five hundred forty-four unselected patients were examined by a radiologist as to the presence or absence of coronary artery calcification. The overall prevalence of coronary calcification was 20% and there was a definite increase in the prevalence of the finding with increasing age. A comparison of 94 patients with coronary calcification with a matched control group without calcification indicated that the prevalence of symptomatic ischemic heart disease in the group with calcification was approximately twice that of the control group. The correlation was even more significant when the degree of calcification was moderate or severe.

It is concluded that cardiac fluoroscopy with image intensification is a useful supplementary tool in the clinical evaluation of patients suspected of having coronary artery disease. It can be performed easily and imposes no risk to the patient.
Pulmonary Hypertension Associated with Cirrhosis of the Liver and with Portacaval Shunts
Authors: SENIOR ROBERT M. , BRITTON RICHARD C. , TURINO GERARD M. , WOOD JOHN A. , LANGER GLENN A. , FISHMAN ALFRED P.
Published: June 2012

Pulmonary hemodynamics were studied in 11 patients with hepatic cirrhosis who had undergone surgical portal decompression several years earlier. Four of the patients had both clinical and physiological evidence of pulmonary hypertension; two others had mild, subclinical pulmonary hypertension. Autopsy examination of two patients who had clinical evidence of pulmonary hypertension revealed thickening of the small pulmonary arteries and multiple small pulmonary emboli. Before the portosystemic venous anastomosis was created, all of the patients had had normal cardiorespiratory performance. These studies suggest that emboli from the portal vein may have been involved in the genesis of the pulmonary hypertension in these patients. The role of surgical portal decompression is unclear. Retrospective studies of 70 clinical records and of 17 autopsy protocols in a similar group of patients did not clarify the role of the surgical decompression in the genesis of the pulmonary hypertension.