bluuebunny/crossref_metadata_2025 huggingface dataset:
Metabolic Studies on Hypertensive Patients with Suppressed Plasma Renin Activity Not Due to Hyperaldosteronism
Authors: HELMER OSCAR M. , JUDSON WALTER E.
Published: June 2012

Metabolic data obtained during sodium depletion (10-mEq Na, 90-mEq K diet plus thiazide) from 13 hypertensive patients (HT) with low plasma renin activity (PRA) were compared with data from 15 normotensive subjects and three patients with renovascular hypertension (RHT). With Na depletion plasma renin activity and urinary aldosterone excretion increased promptly in NT and RHT. In contrast, PRA in HT after 5 days of Na depletion was only one third that of the NT after 2 days of depletion, and aldosterone excretion did not change significantly. This depressed renin and aldosterone response in HT can be overcome by extending the depletion period and administering spironolactone. In HT, Na and loss of weight was significantly lower than in NT. HT Negroes retained more potassium than HT whites and four out of seven NT Negroes and none of eight NT white subjects had a positive K balance. The hypertension of patients with low PRA appears to be due to genetic or environmental factors or to both.
Observations on Heart Block During Continuous Electrocardiographic Monitoring in Myocardial Infarction
Authors: STOCK RICHARD J. , MACKEN DANIEL L.
Published: June 2012

Complete heart block (CHB) was observed in 24 of 350 patients with myocardial infarction who were studied under conditions of continuous electrocardiographic monitoring. CHB occurred predominantly in posterior and anteroseptal infarctions. In posterior infarction CHB was observed in patients who also developed first degree (1°) and types I and II second degree (2°-I and 2°-II) atrioventricular (A-V) block but not bundle-branch block (BBB). In anteroseptal infarction CHB was found in patients with BBB, occasionally in patients with 2°-II A-V block, but not in patients with 1° and 2°-I A-V block. Right BBB with a Q wave in lead V
1
was the usual form of BBB observed in patients with CHB and anteroseptal infarction. One mechanism for sudden death in anteroseptal infarction is the abrupt development of CHB following the onset of BBB. Evidence is presented attributing CHB to a lesion in the A-V node in posterior infarction and to bilateral BBB in anteroseptal infarction.
Successful Surgical Interruption of the Bundle of Kent in a Patient with Wolff-Parkinson-White Syndrome
Authors: COBB FREDERICK R. , BLUMENSCHEIN SARAH D. , SEALY WILL C. , BOINEAU JOHN P. , WAGNER GALEN S. , WALLACE ANDREW G.
Published: June 2012

Recurrent supraventricular tachycardia is a frequent complication in patients with the Wolff-Parkinson-White (WPW) syndrome. Our patient was unusual in that the arrhythmia was the predominant rhythm, and it was felt that the sustained tachycardia was responsible for signs and symptoms of congestive heart failure. The arrhythmia could not be controlled adequately with digitalis, quinidine, diphenylhydantoin, or propranolol. Atrial or ventricular pacing also failed to prevent recurrent episodes of tachycardia.

Physiological and pharmacological studies suggested that an anomalous pathway was responsible for the WPW abnormality and participated in a re-entrant circuit which sustained the episodes of tachycardia. Isopotential body surface mapping suggested anomalous ventricular excitation at the lateral aspect of the right atrioventricular groove. Epicardial mapping at the time of surgery was used to localize the earliest area of anomalous ventricular activation, and surgical transection of the atrioventricular junction at that point abolished the electrocardiographic features of WPW and the recurrent tachycardia. Five months after surgery neither the ECG features of WPW nor the tachycardia has recurred. The signs and symptoms of congestive heart failure have subsided, and the patient has returned to work.
Conversion of Supraventricular Tachycardias with Atrial Stimulation
Authors: HUNT NOEL C. , COBB F. R. , WAXMAN MENASHE B. , ZEFT HOWARD J. , PETER ROBERT H. , MORRIS JAMES J.
Published: June 2012

Atrial stimulation at rates less than the atrial rate was effective in terminating junctional tachycardia and atrial flutter in two patients. Analysis of the stimulus response in the patient with junctional tachycardia defined an atrial excitable and refractory period and a critical interval, the first 12 milliseconds of the excitable period, during which atrial stimulation terminated the tachycardia. The termination of atrial flutter appeared to occur simultaneously with capture of the atrial rate by the slower atrial stimulus. Atrial fibrillation did not occur. These observations suggest that a variety of tachycardias are supported by re-entry mechanisms and that the response to atrial stimulation may be useful in recognizing and treating such arrhythmias.
Bradycardia-Dependent Bundle-Branch Block
Authors: MASSUMI R. A.
Published: June 2012

Four cases of bundle-branch block (BBB) occurring with slow heart rates in patients with heart disease are presented. Recognition of bradycardia-dependent BBB is often difficult, and its differentiation from ventricular escape mechanism and from bilateral BBB requires careful analysis. A set of five criteria based on our own observations is presented with a review of the literature. The responsible mechanism for this seemingly paradoxical situation is not known. However, spontaneous depolarization of one or the other of the bundle branches in late stages of diastole appears to be the most plausible explanation.
Influence of Angiotensin on the Hemodynamic Response to Exercise in Normotensive Subjects
Authors: SANNERSTEDT RUNE , VARNAUSKAS ED
Published: June 2012

The effect of exercise on the systemic hemodynamic response in 11 healthy men has been studied before and during an intravenous infusion of angiotensin sufficient to increase the resting mean arterial blood pressure an average of 29%.

On exercise in the angiotensin period there was a significantly smaller rise of the systolic pressure than on exercise in the control state, and the response of the diastolic pressure was changed from a moderate increase to a decrease on an average. The increase in mean arterial pressure on exercise was almost abolished, being 4.3 mm Hg during the infusion compared with 20.6 mm Hg before infusion. The rise in cardiac output on exercise was significantly smaller during the angiotensin period, while at the same time there were no significant changes in the behavior of the heart rate, stroke volume, or systemic vascular resistance.

The findings indicate that the vasoconstricting effects of angiotensin are largely overcome by the vasodilating effect of exercise in the working muscle groups, but the possibility of relatively increased vasoconstriction in the vascular bed supplying less vitally important tissues is pointed out.
Physiological Analysis of Middle-Aged and Old Former Athletes
Authors: SALTIN BENGT , GRIMBY GUNNAR
Published: June 2012

Blood lipids, red cell volume, heart volume, dynamic spirometry, electrocardiograms made at rest and during exercise, and maximal oxygen uptake were determined in 29 former athletes 45 to 70 years old. The subjects had been very successful competitors in endurance events before the age of 30, but for at least 10 years preceding this study had been sedentary.

Maximal oxygen uptake averaged 40 ml/kg/min which is 20% higher than that of sedentary middle-aged men but 25% lower than that of still active athletes of the same ages. Vital capacity, forced expiratory volume, and maximal voluntary ventilation showed normal values. Heart volume was large in relation to maximal oxygen uptake and was of the same magnitude as in still active athletes. Red cell volume was also large in relation to maximal oxygen uptake, but normal in relation to the body weight. Cholesterol in serum averaged 260 mg/100 ml. Values for neutral fat averaged 1.6 mM, which was higher than that for still active athletes.

In the athletes still active, the frequency of S-T changes was as common as in unselected healthy old men but in the former athletes the frequency was reduced. This was also true for the frequency of right bundle-branch block, ST-junction elevation and high T waves.
The Pulmonary Pressures in Pulmonary Venous Obstruction
Authors: WARREN MERRITT C. , BENARON PHILIP M. , SISSMAN NORMAN J.
Published: June 2012

The contour of the pulmonary artery wedge pressure tracing in a case of pulmonary venous obstruction was unique and may be diagnostic. Wedged pressures were obtained in both a pulmonary artery and a pulmonary vein on recatheterization of a 5-year-old boy with total anomalous pulmonary venous drainage to the superior vena cava on whom an anastomosis of the confluence of the pulmonary veins to the left atrium with loose ligation of the vertical vein had been done at 2 months of age. The pulmonary artery wedge pressure (oxygen saturation, 97%) was 31/18 (mean, 22) mm Hg and its contour was almost identical to that of the pulmonary artery pressure. A similar contour was obtained in the pulmonary vein, for both wedged and free pressures. The similarity of the pulmonary artery wedge pressure to that in the free pulmonary artery may lead to the conclusion that the catheter is not wedged when actually it is. Doubt can be resolved by withdrawing fully saturated blood. Extreme stenosis between the confluence of the pulmonary veins and the left atrium may cause the pulmonary artery wedge to reflect pulmonary arterial rather than left atrial pressure and pulse form.
Endocardial Fibrosis
Authors: CLARK JAMES G. , BUCHELERES H. GUNTHER , CARLETON RICHARD A.
Published: June 2012

Three patients with endocardial fibrosis who had their endocardial pacing thresholds measured are described. The threshold values were elevated to at least twice normal levels. By determining the endocardial pacing threshold value, a technique is available for detection of endocardial fibrosis during diagnostic cardiac catheterization.
Post-Traumatic Aneurysm of the Left Ventricle
Authors: KILLEN DUNCAN A. , GOBBEL WALTER G. , FRANCE RICHARD , VIX VERNON A.
Published: June 2012

Three cases of left ventricular aneurysm secondary to external violence are reported. Each patient presented with a pseudoaneurysm of the left ventricle, following penetrating trauma in two instances and blunt trauma in the third instance. The interval between injury and diagnosis ranged from 5 months to 24 years. Two patients underwent successful resection of the aneurysm. Repair was not attempted in the third patient. Only 16 cases of post-traumatic left ventricular aneurysm have previously been reported. In 13 of the 19 cases available for review, the trauma was blunt and in six penetrating. The aneurysm could be determined to be a true aneurysm in five instances and a false aneurysm in eight instances. Complications (rupture, cardiac failure, embolism, and arrhythmia) proved fatal in eight cases. Each of the eight patients subjected to aneurysmectomy survived.
Dysplasia of the Systemic and Pulmonary Arterial System with Tortuosity and Lengthening of the Arteries
Authors: BEUREN ALOIS J. , HORT WALDEMAR , KALBFLEISCH HEINRICH , MÜLLER HELMUTH , STOERMER JOACHIM
Published: June 2012

This article describes the case of a boy, 1 year and 5 months old, with generalized tortuosity and lengthening of all major arteries, including the coronary arteries and the pulmonary artery. The early death of the patient was attributed to coronary insufficiency and multiple severe peripheral pulmonary stenoses.

The pathological changes were confined to the elastic arteries and the first part of the muscular arteries. The wall of the aorta was thickened and there was an increase of the elastic fibers. The same changes were present in the main pulmonary artery. In the large muscular arteries, the characteristic changes were thickening of the intima with hyperplasia of the elastic fibers and degenerative fragmentation of the internal elastic membrane. The walls of the coronary arteries were thickened and their lumina were narrow.
Lymphopericardium with Hypoproteinemia, Intestinal Loss of Protein, and Congenital Defects of the Lymphatic System
Authors: OFFERIJNS F. G. J. , VAN DER VEEN K. J. , DURRER D. , DES PLANTES B. G. ZIEDSES
Published: June 2012

In the case of the 19-year-old girl reported, lymphopericardium was associated with congenital abnormalities of the lymphatic system and with gastrointestinal loss of protein secondary to intestinal lymphangiectasia. No communication with the thoracic duct was found.
Temperature of the Great Toe as an Indication of the Severity of Shock
Authors: JOLY HENRI R. , WEIL MAX HARRY
Published: June 2012

To establish whether changes in skin temperature would provide objective indication of the presence and severity of shock, hemodynamic and temperature measurements were obtained with the aid of a digital computer. Values obtained 3 hours after admission and 3 hours prior to discharge or death in 100 patients who presented with clinical signs of circulatory shock were analyzed. Temperature was measured with standard thermistor probes at five sites: the digital pad of the third finger, the large toe, the deltoid region of the arm, the lateral portion of the thigh, and the rectum.

A significant correlation was demonstrated between the cardiac output and temperature of the toe (r = 0.71). Correlations were increased to 0.73 when corrections were made for changes in ambient temperature. A stepwise regression analysis provided no significant improvement in the predictability of cardiac index when the values for temperatures of other skin sites were included. Discriminant function analysis showed that an early measurement of toe temperature correctly predicts patient outcome 67% of the time.
Rapid Sequential Visualization of the Heart and Great Vessels in Man Using the Wide-Field Anger Scintillation Camera
Authors: MASON DEAN T. , ASHBURN WILLIAM L. , HARBERT JOHN C. , COHEN LAWRENCE SANFORD , BRAUNWALD EUGENE
Published: June 2012

The recent development of the instantaneously sensing Anger scintillation camera, capable of recording wide-field radioisotope images from the precordium, and a system for video storage and analysis has provided a means of visualizing the anatomic and hemodynamic features of the heart and great vessels without the hazards involved in introducing a radiopaque agent. Sodium pertechnetate (
99m
TcO

4
-

) produces no cardiocirculatory effects or untoward actions and delivers only 0.13 rads of total body radiation. Following injection, the rapidly changing distribution of radioactivity within the heart is recorded by the scintillation camera-television system which includes no inherent dead time or overlap of the scanned field from frame to frame. Video tape replay is available immediately and sequential integrated pictures are possible at any rate up to 60 sec. Radioisotope images of longer intervals are easily obtained by the integration of successive stop-action fields reproduced on a high resolution television monitor and photographed on rapidly developed film. In addition, the replay may be gated and tracked, allowing selected phases to be integrated and time-concentration curves of blood flow.

Five to 10 millicuries of
99m
TcO

4
-

in 2 to 8 cc were rapidly injected into selected cardiac chambers at the time of diagnostic catheterization in 50 patients with a variety of congenital and acquired forms of heart disease. Movement of radioisotope closely reflected the hemodynamic alterations caused by these conditions, as determined by standard contrast angiocardiography. The radioisotope-angiocardiogram provides a new approach for visualization of the cardiovascular system, does not require the use of radiopaque medium, is safer than angiography, and does not disturb circulatory function.
Cardioversion and Digitalis
Authors: WITTENBERG STEPHEN M. , LOWN BERNARD
Published: June 2012

Experiments were performed in anesthetized dogs to study some effects of propranolol, dextro-propranolol and ICI50,172 on digitalis-induced arrhythmias and digitalis-induced sensitization to electrical shock. When given in beta-blocking doses, propranolol did not abbreviate ouabain-induced ventricular tachycardia (VT) or decrease ouabain-induced sensitization to electrical shock. In larger doses, propranolol first controlled the arrhythmia without affecting shock sensitivity and then abolished both arrhythmia and shock sensitivity. Dextro-propranolol, a compound with nonspecific antiarrhythmic action equal to that of propranolol but with virtually no beta-blocking effect, abolished shock sensitivity, whereas ICI50,172, a pure beta-blocking agent, did not. Beta-blocking doses of propranolol given to dogs bordering on digitalis toxicity but in normal sinus rhythm caused recurrence of sustained ventricular tachycardia. Reappearance of toxicity appeared to be related to a propranolol-induced decrease in heart rate, since it was averted during continuous electrical pacing of the atrium and reversed by isoproterenol administration.
Diminished Baroreflex Sensitivity in High Blood Pressure
Authors: BRISTOW J. DAVID , HONOUR A. JOHN , PICKERING GEORGE W. , SLEIGHT PETER , SMYTH HARLEY S.
Published: June 2012

Sudden intravenous injections of small amounts of angiotensin or phenylephrine were given to 30 subjects to produce modest, brief increases in directly measured systemic arterial pressure. A plot of each systolic pressure against the second succeeding cardiac cycle length produced a linear distribution, the slope of which was expressed as the millisecond increase in cycle length per mm Hg rise in systolic pressure. The slope is an index of baroreflex sensitivity and was found to have an average value of 12.8 in 18 subjects without hypertension and 2.8 in 12 others with hypertension. When all results were pooled, there was an inverse relationship between the resting mean arterial pressure and slope of the baroreflex regression lines. The findings demonstrate reduced sensitivity of the baroreflexes in hypertension, with respect to control of heart rate. A distinction is made between this change in sensitivity and simple resetting of the reflex.
Immunological Tolerance in Organ Transplantation
Authors: NOSSAL G. J. V.
Published: June 2012

A formidable array of practical problems must be solved at laboratory level before tolerance induction in organ transplantation can be considered a realistic clinical possibility. I believe it is too early for even tentative human experimentation in this field. However, the work of the last decade has shown unequivocally that even adult animals can readily be rendered tolerant of even
exceedingly powerful
antigens. The principle of tolerance has such great specificity and such compelling elegance when compared with present-day aids to organ transplantation that intensive effort must go into harnessing it to clinical use. It will certainly enter the clinical homograft scene within a decade, and xenografts are inconceivable in its absence.
Computer Diagnosis of Biventricular Hypertrophy from the Orthogonal Electrocardiogram
Authors: GAMBOA RAUL , KLINGEMAN JACK D. , PIPBERGER HUBERT V.
Published: June 2012

Orthogonal electrocardiograms obtained from 87 patients with necropsy evidence of biventricular hypertrophy (BVH) were compared to record samples obtained from normal subjects (N) and patients with left or right ventricular hypertrophy (LVH or RVH). From 333 different ECG measurements an attempt was made to select optimal discriminators of the various pathological entities. The best separation between the BVH sample and other entities was obtained by utilizing linear discriminant function analysis and a likelihood ratio test. By using a combined covariance matrix of BVH versus N, LVH, and RVH, 69% of the BVH sample was correctly classified, thus demonstrating that multivariate analysis can lead to a substantial improvement in diagnostic classification over previous studies reported in the literature.

To test the multivariate classification method against completely independent record samples, new series of LVH and RVH cases were compared to the BVH sample. The results were similar to those obtained against the original samples. When a "clinical" BVH sample was classified by the combined covariance matrix, 44% of the new cases were classified correctly.

A search was also made for optimal scalar and vectorial measurements that can be used in routine ECG interpretation without access to computer facilities. On using 96 percentile ranges, the separations were less efficient than those obtained by multivariate analysis but they still compared very favorably with previous reports.
Type II Hyperlipoproteinemia in Mother and Twins
Authors: LEE GERALD B. , CULLEY GREGORY A. , LAWSON MAREN J. , ADCOCK LEON L. , KRIVIT WILLIAM
Published: June 2012

A 36-year-old housewife with type II hyperlipoproteinemia became pregnant with twins. Although the pregnancy was uneventful, the serum triglycerides were elevated during the third trimester, the delivery, and early puerperium. The mother had no complications directly related to the pregnancy despite hypercholesterolemia, coronary atherosclerosis, and hypertension. Cord blood cholesterol and beta lipoprotein in both twins were greater than twice normal. Despite this genetic defect in lipid transport the twins have developed normally during their first year of life. Since lipids and lipoproteins do not cross the placental barrier, it is concluded that type II hyperlipoproteinemia may have been present at birth.
A Reproducible Model of Cardiogenic Shock in the Dog
Authors: LLUCH S. , MOGUILEVSKY H. C. , PIETRA G. , SHAFFER A. B. , HIRSCH L. J. , FISHMAN A. P.
Published: June 2012

An animal model of cardiogenic shock has been developed in the intact unanesthetized dog. Selective embolization of the circumflex coronary artery with 0.2 ml of mercury produces infarction of the posterolateral wall of the left ventricle and a shocklike state in the dog which results in death of the animal in 5 to 48 hr. The syndrome of cardiogenic shock in the animal model simulates closely that observed in man. Systemic blood pressure falls sharply (25 to 30% of control) immediately after embolization, remains low for several hours, then slowly increases toward normal, but never reaches preinfarct levels. The left ventricular end-diastolic pressure (LVEDP) remains within normal limits (5 to 10 mm Hg) during the initial hypotensive state, but increases to values above 10 mm Hg during the period of rising systemic pressures. As left ventricular failure begins to develop as evidenced by the rise in LVEDP, the mean pulmonary artery pressure also rises above control values. The cardiac output falls to 40% of control levels following embolization and never recovers. Peripheral resistance rises to compensate for the reduction of cardiac output and remains above control levels. Electrocardiograms indicate an essentially normal sinus rhythm with short runs (5 to 15 beats) of ventricular tachycardia with A-V dissociation. The hypotensive state does not seem to be related to this arrhythmia. Death of the animal appears to be due to progressive failure of the left ventricular pump to maintain cardiac output and systemic pressures.
Pharmacodynamic Effects of a New Antihypertensive Drug, Catapres (ST-155)
Authors: ONESTI GADDO , SCHWARTZ ALLAN B. , KIM KWAN E. , SWARTZ CHARLES , BREST ALBERT N.
Published: June 2012

Catapres is a new imidazoline compound with potent antihypertensive properties. Significant reduction in blood pressure occurs between 1 and 4 hours after oral administration, with the peak effect occurring at 2 to 4 hours and the antihypertensive effect extending for 6 to 10 hours. Blood pressure is reduced in both the supine and erect positions, although the orthostatic response is the more prominent.

Cardiac output is reduced moderately in both the supine and erect positions. Peripheral vascular resistance is also reduced, particularly in the erect posture. Accordingly, the cardiac hemodynamic findings suggest that the antihypertensive effect of Catapres is related to the combination of reduction in cardiac output plus decrease in peripheral resistance. Renal blood flow and glomerular filtration rate are preserved in both the supine and erect positions following Catapres administration. Contrasting with the preservation of renal blood flow and glomerular filtration rate, however, is the marked reduction in sodium chloride excretion which follows acute administration of the drug.

The clinical utility of the drug was demonstrated in the chronic outpatient study. Although Catapres administered alone exerted only modest antihypertensive effects, a markedly enhanced antihypertensive response was achieved when the drug was combined with a potent oral diuretic, with 80% of patients so treated achieving significant blood pressure reduction in both the supine and erect positions.
Spatial Parameters and Shape Factors of the Normal Atrial Vectorcardiogram and Its Scalar Components
Authors: BRODY DANIEL A. , COX JOHN W. , MCEACHRAN ANN B. , GILES HANNELORE H. , RUESTA VICTOR J. , Phillips Harry A. , Eddlemon Charles O.
Published: June 2012

New quantitative norms for clinical evaluation of the atrial vectorcardiogram are presented. Real-time computer processing digitizes atrial electrocardiograms, reduces random noise content, rectifies base-line configuration, and corrects preamplifier distortion. Axial-system leads of 106 normal persons were so treated. The basic information derived includes spatial distribution and magnitudes of P, T
P
, and polar P vectors; length, width, and planarity of P loops; spatial P-T
P
angles; and the Eulerian angles of P-loop normalization. Normal P vectors show predominant leftward, inferior, and anterior orientation, with opposing T
P
direction. Polar P vectors show predominant superior, anterior, and leftward clustering. The scatter of parameters in the orthogonallead frontal plane is about the same as for the tetrahedral system. Similarly, the atrial deflections of normals show equally rich notching in both systems. Resolution of the P-wave population into uncorrelated components, followed by resynthesis from these principal factor wave forms, revealed a fairly continuous "spectrum" of signal configurations. This technique, and extensive attempts by alternate means, failed to support the view that normal P waves can be separated into distinctive right and left atrial components.
Analysis of the Orthogonal Electrocardiogram and Vectorcardiogram in Ventricular Conduction Defects With and Without Myocardial Infarction
Authors: GOLDMAN MERVIN J. , PIPBERGER HUBERT V.
Published: June 2012

Correlations were computed for 320 electrocardiographic measurements and variables of ventricular conduction defects in 452 unselected patients. The variables consisted of right and left ventricular conduction defects with and without myocardial infarction. Quantitative criteria were established which led to the identification of infarction in the presence of a ventricular conduction defect. The data were analyzed by two methods: (1) using four independent measurements, and (2) discriminant function analysis in conjunction with a likelihood ratio test using 9 or 10 measurements. Both techniques yielded similar results. In the presence of left ventricular conduction defects 52% of the cases of infarction were identified with a 14% false positive diagnosis of infarction. In the cases of right ventricular conduction defects the results were 54% and 11%, respectively. In both, the sensitivity could be increased at the expense of an increase in the false positive frequency. This study confirms the difficulties in the electrocardiographic diagnosis of infarction in the presence of left ventricular conduction defects. In addition, it emphasizes that a simlar problem exists with right ventricular conduction defects, a finding which has not been adequately appreciated to date.
Effect of Reserpine in Raynaud's Phenomenon
Authors: KONTOS HERMES A. , WASSERMAN ALBERT J.
Published: June 2012

The responses of the blood vessels of the hand to intra-arterial infusion of tyramine and to application of ice to the forehead were examined in patients with Raynaud's phenomenon and in normal subjects. The vasoconstrictor responses to tyramine and to ice were not significantly different in the patients and control subjects. Following intra-arterial administration of reserpine the vasoconstrictor response to tyramine was unaffected, while that in response to ice was significantly reduced to a comparable extent in both the patients and the control subjects. Catecholamine concentrations in brachial arterial and hand venous plasma were not significantly different in the patients and in the control subjects. Following oral administration of reserpine (1 mg/day) the vasoconstrictor responses to intra-arterial tyramine and to the application of ice were markedly reduced in patients with Raynaud's phenomenon. In response to this form of treatment eight of the nine patients followed for 1 to 3 years showed improvement characterized by decreased frequency and severity of vasospastic attacks and by healing of ulcerations. In two patients the improvement was temporary despite continued reserpine therapy.
Study of Atrioventricular Conduction in Man Using Electrode Catheter Recordings of His Bundle Activity
Authors: DAMATO ANTHONY N. , LAU SUN H. , HELFANT RICHARD H. , STEIN EMANUEL , BERKOWITZ WALTER D. , COHEN STAFFORD I.
Published: June 2012

The technique of recording electrograms of the His bundle, using a tripolar electrode catheter positioned across the tricuspid valve, was applied in a physiological study of atrioventricular conduction in man. Increasing the heart rate to 160 beats/min by right atrial pacing produced progressive prolongation of the P-H interval while the H-Q interval remained constant. At any given paced heart rate, digitalis caused a prolongation of the P-H interval. Isoproterenol and atropine markedly shortened the P-H interval at any given heart rate. Neither drug had any significant effect on the H-Q interval. Coupled premature atrial stimulation produced prolongation of the P-H interval alone when the resultant ventricular depolarization was normal, and prolongation of both the P-H and H-Q intervals when the resultant ventricular depolarization was aberrant.
A Hemodynamic Comparison of Dopamine and Isoproterenol in Patients in Shock
Authors: TALLEY ROBERT C. , GOLDBERG LEON I. , JOHNSON CHARLES E. , MCNAY JOHN L.
Published: June 2012

The hemodynamic responses to isoproterenol and dopamine were investigated in 22 patients with the shock syndrome from various etiologies. Dopamine was superior to isoproterenol in seven patients with normal or low peripheral resistance. In this group of patients administration of isoproterenol was associated with unacceptably low blood pressure. Isoproterenol was superior in three patients in whom dopamine did not increase cardiac output. Both amines produced adequate clinical response in four patients, and a combination of isoproterenol and dopamine was necessary for adequate therapy in two patients. Six patients did not respond hemodynamically or clinically to either dopamine or isoproterenol. This investigation has demonstrated that optimal sympathomimetic amine therapy of shock is facilitated by an analysis of hemodynamic status and responses to drug administration.
Measurements and a Simplified Interpretation of Magnetocardiograms from Humans
Authors: COHEN DAVID , CHANDLER LOUIS
Published: June 2012

To understand and assess the magnetocardiograph, the magnetic field produced by electrical heart activity was mapped around the torsos of one abnormal and six normal heart subjects, at different times during QRS. The measurements are here presented in the form of instantaneous distributions of vector segments 6 cm from the skin, anteriorly. An electrical model is presented which explains the first-order features of these distributions. This model is a simple, rotating bipole heart source of changing strength which produces the same ion currents as measured with surface electrocardiograms and vectorcardiograms; these currents produce a time-changing magnetic field extending outside the torso. Further analysis of second-order details of the distributions can reveal information not obtainable with various forms of surface electrocardiography.
Recording of Specialized Conducting Fibers (A-V Nodal, His Bundle, and Right Bundle Branch) in Man Using an Electrode Catheter Technic
Authors: DAMATO ANTHONY N. , LAU SUN H. , BERKOWITZ WALTER D. , ROSEN KENNETH M. , LISI KENNETH R.
Published: June 2012

Extracellular action potentials of the A-V node (N), His bundle (H), and right bundle branch (RB) were recorded in subjects with an electrode cardiac catheter which was fluoroscopically positioned across the tricuspid valve. The N potential is a slow diphasic wave occurring between the atrial electrogram (P) and the H potential. It is characterized by slurring or notching on the upstroke. The H potential, as previously described, is a biphasic or triphasic wave of 15 to 20-msec duration. The RB potential is a fast biphasic wave of 10 to 20-msec duration occurring between the H potential and the Q wave. During single atrial pacing and premature atrial stimulation, the A-V conduction delay could be localized to the N-H interval. Evidence suggests that during aberrant ventricular conduction of the right bundle-branch block type the impulse was blocked proximally in the right bundle. During concealed conduction the nonconducted impulse was completely blocked within the A-V node or the N-H interval.
Digoxin Metabolism in the Elderly
Authors: EWY GORDON A. , KAPADIA GEETA G. , YAO LINDA , LULLIN MURIEL , MARCUS FRANK I.
Published: June 2012

Tritiated digoxin (0.5 mg) was given intravenously to five elderly men (mean age, 77 years) and nine young men (mean age, 27 years). The elderly were not in congestive heart failure. The serum creatinines of the old and young were not different. However, the creatinine clearance averaged 56 ml/min/1.73 m
2
in the old and 122 ml/min/1.73 m
2
in the young (
P
<0.001). Digoxin clearance averaged 53 ml/min/1.73 m
2
in the old and 83 ml/min/1.73 m
2
in the young (
P
<0.001). The blood concentrations of tritiated digoxin were significantly higher in the elderly throughout the study (
P
<0.05). When blood digoxin concentrations were corrected for body surface area, there was no significant difference between the two groups during the first 24 hr, but thereafter the concentrations in the elderly were higher.

The same dose of digoxin resulted in higher blood concentrations and longer blood half-life in the elderly. This is due to the smaller body size and a diminished urinary excretion of digoxin in the elderly.
Korotkoff Sounds
Authors: TAVEL MORTON E. , FARIS JAMES , NASSER WILLIAM K. , FEIGENBAUM HARVEY , FISCH CHARLES
Published: June 2012

We have studied Korotkoff sounds in 10 subjects by recording pressures and sounds simultaneously through a brachial arterial needle at locations both beyond and beneath the inflatable cuff. The Korotkoff sounds coincided with a small dip and ensuing steep rise in pressure immediately beyond the distal edge of the cuff. Sound intensity paralleled not only the rate and the acceleration of this steep ascent, but also the total pressure through which it was maintained. Pressures beneath the midportion of the cuff showed a more pronounced sharp initial negative dip, usually followed by a rapid reversal and steep rise, and the sounds were also recorded here in association with these rapid pressure changes. This study supports the hypothesis that the initial Korotkoff sound is produced by rapid changes of pressure both beneath and distal to the compressing cuff, sufficient in rate to impart sonic vibrations to the vessel wall and surrounding tissues. We have attempted to explain how these rapid pressure changes are produced.
Maximal Treadmill Stress Testing for Cardiovascular Evaluation
Authors: ELLESTAD MYRVIN H. , ALLEN WILLIAM , WAN MAURICE C. K. , KEMP GEORGE L.
Published: June 2012

Experience with a maximal treadmill stress testing procedure which is relatively safe, simple, and reproducible is reported. It has been used in normal persons and cardiac patients with ages ranging from 7 to 83 years. There have been no deaths in our total experience of 4,028 maximal capacity stress tests. Maximal capacity is predicted by the patient's peak predicted pulse rate. Sixty-three per cent of those with ischemic S-T segments did not experience pain of any type.
Limitations in the Feasibility of Pulmonary Embolectomy
Authors: GIFFORD RAY W. , GROVES LAURENCE K.
Published: June 2012

Of 101 patients who had major pulmonary emboli confirmed at autopsy, 44 died within 1 hour of the onset of symptoms; 26 had no abrupt change in the clinical course to indicate the presence of emboli; and three died while they were under anesthesia. Of the 28 patients who survived for more than 1 hour after onset of symptoms, seven had incurable malignant lesions, four were unconscious with irreversible brain damage, six were too ill from other diseases to undergo embolectomy, and the diagnosis was not suspected for five. Consequently, of the 101 patients only six would have been selected to undergo pulmonary embolectomy. Only by increasing our diagnostic acumen and by obtaining pulmonary angiograms as soon as possible after onset of symptoms can this salvage rate be improved.
The Coronary Arteries in Early Life in Three Different Ethnic Groups
Authors: VLODAVER ZEEV , KAHN HAROLD A. , NEUFELD HENRY N.
Published: June 2012

The histologic changes in the coronary arteries in full-term fetuses, infants, and children of 211 consecutive necropsy specimens from Ashkenazy, Yemenite, and Bedouin groups were studied, excluding cardiac deaths.

The developmental structural pattern of the coronary arteries is similar in the three ethnic groups.

Differences in the intensity and quantity of the structural findings between the sexes and among various ethnic groups are found in early life. The intimal tissue in the Ashkenazy male develops in an eccentric form, has more collagen tissue components, and is more highly developed than in the Ashkenazy female. Structural findings in the internal elastic membrane and the elastic fibers of the intima are less apparent in the Bedouin group, particularly in the female, than in the Ashkenazy and Yemenite groups.

Statistical analysis of the quantitative data showed the intima and musculo-elastic layers to be more developed in the Ashkenazy male than in the Yemenite and Bedouin males. However, Ashkenazy males clearly have more intima and musculo-elastic tissue than do the Ashkenazy females. This was not true for Yemenites and was found in only one of three age groups among Bedouins.

The relationship between the structural findings in coronary arteries of children under 10 years and the reported prevalence of coronary heart disease in the corresponding adult population in these three different ethnic groups has been pointed out.
Aorta to Right Pulmonary Artery Anastomosis (Waterston's Operation) for Cyanotic Heart Disease
Authors: SOMERVILLE JANE , YACOUB M. , ROSS D. N. , ROSS K.
Published: June 2012

Thirty patients with cyanotic heart disease, including Fallot's tetralogy, transposition of the great arteries, and tricuspid atresia had Waterston's anastomosis for gross effort intolerance or cyanotic attacks. The results were good in 28. Spontaneous closure of the anastomosis occurred in one patient. There was a tendency for preferential perfusion of the right lung, and unilateral pulmonary edema occurred in nine patients. Congestive heart failure appeared when the stoma was too large. Surgical technic to avoid kinking of the right pulmonary artery has been modified, and the importance of limiting the size of the anastomosis has been emphasized. Transaortic closure of the anastomosis through the aorta at the time of definitive correction was simple in three patients.
Subpulmonic Obstruction in Complete (d) Transposition Produced by Redundant Tricuspid Tissue
Authors: RIEMENSCHNEIDER THOMAS A. , GOLDBERG STANLEY J. , RUTTENBERG HERBERT D. , GYEPES MICHAEL T.
Published: June 2012

Two cases are reported in which complete transposition of the great vessels was associated with an unusual form of subpulmonic obstruction. In each case, redundant tricuspid valvular tissue protruded through a ventricular septal defect into the left ventricular outflow tract, producing severe obstruction to the outflow of blood from the left ventricle.

The clinical course suggested the presence of left ventricular outflow obstruction. Both patients demonstrated progressive clinical deterioration characterized by increasing cyanosis, respiratory distress, and decrease in intensity of the cardiac murmur. Serial laboratory determinations revealed increasing hemoglobin and decreasing systemic oxygen saturation. The clinical deterioration was relieved only temporarily by atrial balloon septostomy.

The angiographic findings appear to be specific for this type of subpulmonic obstruction. In each case, a large asymmetric filling defect was demonstrated at the anterior border of the left ventricular outflow tract below the pulmonic valve.

When the clinical and laboratory findings suggest pulmonary or subpulmonary obstruction, careful evaluation of the outflow tract is indicated. If diagnosed clinically, redundant tricuspid tissue could perhaps be resected during a definitive operation, thus relieving the outflow obstruction.
The Dicrotic Arterial Pulse
Authors: EWY GORDON A. , RIOS JORGE C. , MARCUS FRANK I.
Published: June 2012

The study consisted of observations on nine male patients with palpable dicrotic as evidenced by cardiomegaly and the presence of prominent atrial and ventricular diastolic gallop sounds. Most of these patients were diagnosed as having primary myocardial disease.

The indirect carotid pulse was characterized by a single systolic wave, a low dicrotic notch, and a large dicrotic wave. The direct brachial arterial pressure pulse had a similar configuration with a shortened ejection time index. The hemodynamic data on these patients was characterized by low cardiac output, low stroke volume, elevated pulmonary arterial wedge pressures, and high total systemic resistance. From these observations we conclude that the presence of a marked dicrotic pulse in afebrile patients at rest may indicate severe functional impairment of the myocardium.
Gamma-Glutamyl-Transpeptidase in Myocardial Infarction
Authors: RAVENS KURT G. , GUDBJARNASON SIGMUNDUR , COWAN CHARLES M. , BING RICHARD J.
Published: June 2012

The activity of γ-glutamyl-transpeptidase was determined serially in patients with acute myocardial infarction up to 32 days after the onset of chest pain. Peak enzyme activity was found in all patients between the eighth and eleventh day after infarction. Some patients showed a rise in serum activity 48 hr after infarction.

In 33 mongrel dogs with experimental myocardial infarction, γ-glutamyl-transpeptidase activity was estimated in the homogenate of the normal and necrotic heart muscle as soluble and particle-bound enzyme activity. The changes of free and particle-bound activity showed different patterns. The soluble enzyme activity was highest during the first 4 days and approached normal level after 8 days. Particle-bound activity was significantly decreased after 24 hr and showed thereafter a continuous rise to 10 times the control values 10 days after the coronary artery occlusion.

These studies indicate that several determinations of γ-glutamyl-transpeptidase activity in serum of patients with myocardial infarction may reflect the reparative processes taking place in the infarcted tissue.
Hemodynamic Evaluation of a Cloth-Covered Starr-Edwards Valve Prosthesis
Authors: KLOSTER FRANK E. , HERR RODNEY H. , STARR ALBERT , GRISWOLD HERBERT E.
Published: June 2012

Hemodynamic studies were performed in 22 patients three to ten months after insertion of cloth-covered Starr-Edwards prostheses. The aortic valve was replaced in ten patients, the mitral in ten, and both valves in two.

Moderate aortic systolic pressure gradients were found in all patients with aortic prostheses (range 17 to 68 mm Hg, mean 41 mm Hg), and the calculated valve orifice areas were small (average 0.92 cm
2
). Mitral diastolic pressure gradients in those with mitral prostheses averaged 9.4 mm Hg and were associated with persistently elevated left atrial pressure (average 18 mm Hg).

These findings compare unfavorably with the hemodynamic characteristics of previous Starr-Edwards prostheses. Factors contributing to the functional stenosis appear to be smaller valve orifices and turbulent blood flow generated by the coarse cloth surfaces and a shorter excursion of the ball.
Effect of Dipyridamole on the Incidence of Arterial Emboli After Cardiac Valve Replacement
Authors: SULLIVAN JAY M. , HARKEN DWIGHT E. , GORLIN RICHARD
Published: June 2012

Dipyridamole is a vasodilator known to reduce platelet adhesiveness and aggregation. Either dipyridamole or a placebo was given in a daily dose of 400 mg as a random, blind trial to 100 patients who had undergone prosthetic cardiac valve replacement. Patients in both groups were anticoagulated with warfarin sodium. Fifty patients of the placebo group followed for 695 months had 18% incidence of systemic arterial embolism. Forty-two patients in the dipyridamole group were followed for 553 months. One patient exhibited clinical evidence of arterial embolism. Dipyridamole was discontinued shortly after surgery in eight patients followed for 119 months. Two of these patients developed cerebral emboli six months after discontinuation of treatment. It is tentatively concluded that the addition of dipyridamole to a program of anticoagulation reduces the incidence of postoperative arterial emboli originating on prosthetic cardiac valves in those patients who can tolerate the drug.
Embolic Complications Following Repair of Atrial Septal Defects
Authors: HAWE ANTHONY , RASTELLI G. C. , BRANDENBURG ROBERT O. , MCGOON DWIGHT C.
Published: June 2012

Postoperative embolism occurred in 35 of 546 patients traced for 2 to 15 years after surgical repair of uncomplicated ASD. A total of 58 embolic episodes occurred, resulting in the death of 11 of these 35 patients. The incidence of embolism was not significantly related to the technique used for surgical repair. Six of the nine patients who had had a preoperative embolism also had an embolism in the postoperative period. The most significant factors associated with an increased risk of postoperative embolism were increased age of the patient, atrial fibrillation, and pulmonary hypertension, all of which are interrelated: seventy-seven per cent (27/35) of patients having a postoperative embolism had either atrial fibrillation or pulmonary hypertension, and 77% (27/35) of patients with postoperative embolism were more than 40 years old at the time of the first embolism. Because actuarial analysis suggests that 30% of patients more than 40 years of age who have atrial fibrillation after repair of ASD may have an embolism within 10 years postoperatively, continuation of anticoagulation therapy indefinitely in these patients is suggested. The highest risk of embolism occurs in the early postoperative period, suggesting the advisability of anticoagulation therapy for all adult patients during convalescence.
"Test Banding" of the Pulmonary Artery with a Balloon-Tipped Catheter
Authors: RASHKIND WILLIAM J. , WALDHAUSEN JOHN A. , MILLER WILLIAM W. , DODD PAUL , FRIEDMAN SIDNEY
Published: June 2012

The reactivity of the pulmonary arteriolar bed is determined by "test banding" the pulmonary artery from within. This is accomplished with a double-lumen, balloon-tipped catheter. In the absence of irreversible pulmonary vascular obstructive disease, inflation of the balloon in the pulmonary artery results in a sustained fall in pulmonary artery pressure and a sustained increase in systemic arterial pressure. The technique, performed as an adjunct to the diagnostic catheterization of any patient with significantly elevated pulmonary vascular resistance, is a means of obtaining a preoperative assessment of pulmonary arteriolar reactivity. Three patients in this study were shown to have reactive pulmonary arterioles although they all had pulmonic:systemic flow ratios of 1.3:1 or less and pulmonic:systemic pressure and resistance ratios greater than 0.75, and failed to respond to 100% oxygen inhalation and tolazoline injection.