bluuebunny/crossref_metadata_2025 huggingface dataset:
The Spectrum of Pulmonary Vascular Disease in Transposition of the Great Arteries
Authors: VILES PETER H. , ONGLEY PATRICK A. , TITUS JACK L.
Published: June 2012

Obstructive pulmonary vascular disease (PVD) was evaluated in lung sections taken at autopsy in 53 patients with complete transposition of the great arteries. Twentythree had intact ventricular septa and 30 had ventricular septal defects. Children of similar age and associated defects had widely differing degrees of PVD and presented a spectrum of disease. In a small number of patients, the presence of pulmonic stenosis (congenital or acquired by pulmonary artery banding in infancy), a small ventricular septal defect, or a large atrial septal defect was not protective against the development of severe PVD. The findings of this study demonstrate the need for thorough hemodynamic evaluation of patients with complete transposition of the great arteries prior to repair by present technics. In addition, operation should probably be performed as soon as technically feasible.
Congenital Pulmonary Stenosis Resulting from Dysplasia of Valve
Authors: KORETZKY EMIL D. , MOLLER JAMES H. , KORNS MICHAEL E. , SCHWARTZ COLIN J. , EDWARDS JESSE E.
Published: June 2012

A distinctive type of pulmonary valvular stenosis, termed "pulmonary valvular dysplasia," is described from six necropsies and 10 living children. The anatomic features of the stenotic pulmonary valve are unique in that there are three distinct cusps and no commissural fusion. The obstructive mechanism is related to markedly thickened, immobile cusps, characterized by the presence of disorganized myxomatous tissue.

Several clinical features tend to distinguish this form of pulmonary stenosis. In each of 16 patients studied, a pulmonary ejection murmur was present, but this was not associated with an ejection click. Other features suggestive of this type of pulmonary stenosis were slow body growth, abnormal facies, and a positive family history of pulmonary stenosis. The electrocardiogram showed a greater degree of right axis deviation than is found in most cases of dome-shaped pulmonary stenosis. Right ventriculography revealed distinctive features of the pulmonary valve which were characterized by lack of typical dome-shaped deformity and by the presence of thick cusps.

Experience with simple incision-valvulotomy was associated with a high (38%) operative mortality and significant residual stenosis in survivors. The suggested operative procedures include excision of a valve cusp, placement of a right ventricular outflow patch, or replacement of the pulmonary valve.
Delayed Onset of Hemolytic Anemia in a Child
Authors: MILLER B. LYNN , PEARSON HOWARD A. , WHEAT MYRON W. , WHITE ALVYN W. , SCHIEBLER GEROLD L.
Published: June 2012

Severe intravascular hemolysis is described as a complication of implantation of an aortic Starr-Edwards ball-valve prosthesis and insertion of a Teflon patch in the ascending aorta in a 9-year-old boy with severe aortic valvar stenosis. This progressive hemolysis of delayed onset was the sole indicator of extreme degeneration of the silicone rubber ball of the prosthetic aortic valve, a potentially lethal condition requiring surgical intervention. The phonocardiographic signs of aortic ball variance were not present, and there was no overt valvar incompetence.

A lesser but noteworthy aspect in this case was the occurrence of an "aplastic crisis" superimposed on the severe hemolysis. This transient bone marrow, red cell aplasia, which was unrelated to drugs, precipitated an acutely severe anemia which accounted for the presenting symptoms of the patient and required transfusion.
Wenckebach Periods in the Bundle Branches
Authors: ROSENBAUM MAURICIO B. , NAU GERARDO J. , LEVI RAUL J. , HALPERN M. SUSANA , ELIZARI MARCELO V. , LAZZARI JULIO O.
Published: June 2012

Two cases of intermittent bundle-branch block in which Wenckebach periods could be
directly
visualized are reported. The conduction ratios were either 3:2 or 4:3, as are commonly seen in cases of the Wenckebach phenomenon of atrioventricular (A-V) conduction. Other groups of beats apparently showing 3:1 and 4:1 bundle-branch block were interpreted as indicating
incompletely concealed
Wenckebach periods in the bundle branches, with actual conduction ratios of 3:2 and 4:3, respectively.

Three prerequisites are necessary for the occurrence of either direct or incompletely concealed Wenckebach periods in the bundle branches: (1) The opening beat should be normally conducted (in the affected bundle branch); (2) the second beat should be conducted with a delay of no more than 0.04 to 0.06 sec; (3) the damaged bundle branch should not be activated retrogradely in the closure beat.

Wenckebach periods in the bundle branches may be
completely concealed
if the conduction delay lasts more than 0.04 to 0.06 sec in the opening beat. In cases of bilateral bundle-branch block, Wenckebach periods in the bundle branches may be
indirectly visualized
through changes in the A-V conduction.
Physical Training in the Management of Coronary Artery Disease
Authors: CLAUSEN JAN PRAETORIUS , LARSEN OLE ANDREÉE , TRAP-JENSEN JENS
Published: June 2012

The effects of 4 to 6 weeks' physical conditioning on the cardiovascular and respiratory response to exercise were studied in nine patients with coronary artery disease. Clinical improvement and increased physical working capacity were observed in all patients. The average cardiac output during exercise was unchanged. The stroke volume increased and the myocardial work, assessed by the tension-time index, decreased during exercise at a given work load. It is suggested that at submaximal work loads a reduction of the blood flow to the working muscles occurs after training. Such change might be fundamental for the altered circulatory regulation by allowing a reduced general sympathetic vasoconstriction during exercise. It is concluded that the hemodynamic changes form a rational physiologic basis for the use of physical training in the management of patients with coronary artery disease.
Natural History of Transposition of the Great Arteries
Authors: LIEBMAN JEROME , CULLUM LAWRENCE , BELLOC NEDRA B.
Published: June 2012

The natural history of transposition of the great arteries between 1957 and 1964 is presented based on a total of 742 cases. The area of study was the State of California and included 290 cases from 14 selected hospital centers. It is clear that in this era of more successful surgery, no such study will ever again be possible.

Of major importance has been a compilation of a life table so that present day cardiologists and surgeons, when evaluating whether surgery should be undertaken in a particular patient, can weigh the risk of the operative procedure against the expected number of years of life remaining if surgery is not done.

For the whole group the age of death was as follows: by 1 week, 28.7%; by 1 month, 51.6%; and by 1 year, 89.3%.

The average life expectancy at birth was 0.65 years; at 1 week of age, 0.87 years; at 1 month, 1.12 years; and at 1 year, 3.92 years.

Associated lesions had a marked effect on prognosis. The life tables presented tell a more complete story, and the pertinent data are presented in detail. (See longer summary at end of paper for further information.)
Electrocardiographic Findings in Cardiac Transplantation
Authors: SCHEUER JAMES , SHAVER JAMES A. , HARRIS BARRY C. , LEONARD JAMES J. , BAHNSON HENRY T.
Published: June 2012

This paper outlines the electrocardiographic course of a 46-year-old recipient of a cardiac transplant in whom direct myocardial leads were implanted. There was one episode of decreased QRS voltage with an intraventricular conduction delay, suggestive of an acute immunologic rejection. On one occasion bradycardia occurred, and this was treated by ventricular pacing. There was also an episode of supraventricular tachycardia. Vagotonic maneuvers or agents would not have been appropriate treatment for this arrhythmia. In the presence of both donor and recipient P waves, the interpretation of some of the arrhythmias was difficult.

Since the QRS voltage is important in diagnosing early rejection, great care was taken in accurately standardizing the electrocardiogram and in reproducibly placing electrocardiographic leads. The myocardial leads were found to reflect voltage changes more clearly than surface leads. The presence of myocardial wires also proved convenient for pacing. The use of a right atrial recording electrode is recommended for the diagnosis of complex arrhythmias. This will permit more accurate identification of donor and recipient P waves.
Influence of Amyl Nitrite Inhalation on the Systolic Time Intervals in Normal Subjects and in Patients with Ischemic Heart Disease
Authors: SAWAYAMA TOSHITAMI , OCHIAI MASAKAZU , MARUMOTO SUSUMU , MATSUURA TOHRU , NIKI ISAO
Published: June 2012

The systolic time intervals of the left ventricle in 30 patients with ischemic heart disease but without heart failure were compared with those of 30 normal individuals before and after inhalation of amyl nitrite by using polygraphic recordings.

In the normal subjects, following amyl nitrite, the ejection-time index was significantly prolonged, and the pre-ejection period and its index were significantly reduced, while the ejection time was not significantly shortened. The ischemic heart disease group, however, exhibited no significant changes in the ejection-time index, pre-ejection period, or its index, whereas the ejection time was significantly shortened.

These differences were not related to heart rate or diastolic blood pressure level but may be explained by a postulated lack of increase in stroke volume or in the contractility of the ischemic myocardium, or both, at the maximal effect of amyl nitrite.

The responses of the left ventricular systolic intervals to amyl nitrite may prove useful as a clinical test of latent ventricular functional impairment in subjects with ischemic heart disease.
Coarctation of the Aorta in Infancy
Authors: SINHA SACHCHIDA N. , KARDATZKE MERL L. , COLE ROGER B. , MUSTER ALEXANDER J. , WESSEL HANS U. , PAUL MILTON H.
Published: June 2012

Material from 78 infants with coarctation and congestive heart failure during the first 6 months of life was reviewed. Three fourths of these infants had combined aortic lesions, that is, coarctation, a narrow constrictive zone of stenosis, and tubular hypoplasia of the transverse arch, a proximal, long, uniformly narrow segment.

It was the purpose of this study (1) to distinguish coarctation of the aorta from tubular hypoplasia by using pathologic and angiographic measurements, (2) to assess the relationship of these two entities and additional shunting cardiac defects with the occurrence of congestive heart failure in infancy, and (3) to evaluate the optimal therapeutic approach for symptomatic infants with coarctation.

It was found that (1) coarctation of the aorta as an isolated anomaly is a relatively uncommon cause of congestive heart failure in infancy. In contrast, coarctation associated with tubular hypoplasia of the transverse arch or with additional cardiac defects is frequently associated with severe congestive heart failure. It was found also (2) that surgical management is far more successful than medical management alone in symptomatic infants with coarctation of the aorta and associated significant cardiac defects.
Heart Rate after Cardiac Transplantation
Authors: BECK W. , BARNARD C. N. , SCHRIRE V.
Published: June 2012

Two patients who have undergone heart transplantation 7 and 15 months previously were studied to determine basal heart rate, the effects of exercise, and acute changes in venous return and blood pressure as well as of vagal stimulation. In one case the effects of body temperature, isoprenaline (isoproterenol), beta blockade, and atropinization on heart rate were studied. Mean resting heart rates of 110 and 90, respectively, were observed in the two cases without any significant change with time since the surgical implantation. Sinus arrhythmia was not observed and heart rate was found to increase with exercise following isoprenaline infusion and following increase in body temperature. A decrease was observed after beta blockade, but no significant direct or baroreceptor reflex effects could be produced by changes in venous return, systemic blood pressure, vagal stimulation, and atropinization. Both patients are thus effectively denervated, and there is no evidence of reinnervation to date.
Prodromata in Acute Myocardial Infarction
Authors: SOLOMON HENRY A. , EDWARDS ADRIAN L. , KILLIP THOMAS
Published: June 2012

One hundred patients admitted to a coronary care unit with acute myocardial infarction were interviewed from a structured questionnaire to evaluate the incidence and significance of prodromal symptoms. Prodromata occurred in 65% of the subjects; this is the highest incidence ever recorded. Chest pain was the most common symptom. Characteristically it was recurrent and progressive. Patients with prodromata in contrast to those without warning are more likely to have an anterior or anterolateral infarction and the damage is more likely to be nontransmural than transmural. Prodromata have a striking relationship to pre-existing angina. Patients with angina rarely are hospitalized for acute infarction without warning. Emotional stress was not correlated with the definitive attack of cardiac infarction but was associated with the development of prodromata in some patients. These observations suggest that acute myocardial infarction is usually the culmination of a dynamic pre-coronary process.
Urinary Catecholamine Excretion in Myocardial Infarction
Authors: HAYASHI K. DAVID , MOSS ARTHUR J. , YU PAUL N.
Published: June 2012

The catecholamine excretion rates in urine were studied in three groups of patients with acute myocardial infarction. Group I patients had no complications. Group II patients had minor complications. In groups I and II urine was obtained during the first night of the patient's admission. Group III patients had major complications, and urine was collected during one episode of complications. Catecholamines were measured by spectrophotofluorometric assay using the trihydroxyindole method.

A lack of elevation in basal catecholamine excretion in patients without complications and an elevated catecholamine excretion in those with complications suggest that myocardial necrosis or ischemia per se is not responsible for increased catecholamine excretion and that the increase in catecholamine excretion may reflect the presence of complicating factors.

Recurrent or persisting chest pain, pulmonary congestion or edema, and ventricular arrhythmias were almost always associated with elevated catecholamine excretion. Although in some cases a causal relationship of these complications with observed increase in catecholamine excretion is suggested, further study is required for a definitive conclusion.
His Bundle Rhythm
Authors: DAMATO ANTHONY N. , LAU SUN H.
Published: June 2012

Traditionally the site of impulse formation in so-called A-V nodal rhythms has been considered to be within the upper, middle, and lower portions of the A-V node. In this study, evidence obtained supports the concept that the His bundle and not the A-V node is the pacemaker site in nodal rhythms. His bundle activity was recorded in clinical cases of nodal rhythms and A-V dissociation by using an electrode catheter positioned at the tricuspid valve. In these studies a single His deflection preceded each QRS complex. From the results of this study, it is suggested that in so-called lower and middle nodal rhythms the pacemaker site is within the His bundle. It is further suggested that so-called upper nodal rhythms may represent a coronary sinus or inferior left atrial rhythm.
The Excretion of Tritiated Digoxin in Normal Human Volunteers Before and After Unilateral Nephrectomy
Authors: DOHERTY JAMES E. , FLANIGAN WILLIAM J. , PATTERSON RODNEY M. , DALRYMPLE GLENN V. , Gammill Jacquelyn , Sherwood Joyce
Published: June 2012

Six normal human volunteers as renal transplant donors were given
3
H-digoxin before and again after unilateral nephrectomy. The serum digoxin concentration was modestly increased following nephrectomy, the serum digoxin half-time was slightly prolonged, and total digoxin excretion for the group was reduced by only 6.4% during a 7-day study. Four of the six patients studied before and after unilateral nephrectomy exhibited no important reduction in digoxin excretion after nephrectomy; two patients excreted only 66% and 64% as much of the administered dose of digoxin as they had excreted compared to the control study. The removal of one kidney from an individual whose remaining kidney is normal does not usually cause significant reduction in the excretion of tritiated digoxin, and one may conclude that in such instances nephrectomy should not in itself prompt a change in digoxin dosage provided the remaining kidney achieves its expected increased functional capacity. The adequacy of renal function determines digoxin excretion and the dosage of digoxin in these patients.
Hepatic Injury Caused by
L
-Alpha-Methyldopa
Authors: ELKINGTON S. G. , SCHREIBER W. M. , CONN H. O.
Published: June 2012

L
-alpha-methyldopa (Aldomet)-induced liver disease is a relatively mild and uncommon complication of therapy with this drug. Most commonly it is characterized by a rise in serum alkaline phosphatase, glutamic oxaloacetic transaminase levels, and increased Bromsulphalein retention. Elevation of the serum bilirubin may occur. In its most benign form the condition is usually symptomless, but complaints, such as anorexia, abdominal pain, or pruritus, and signs, such as fever or hepatomegaly, may occur. Histologic changes similar to those of viral hepatitis have been observed. The condition is usually benign and remits on withdrawal of the drug. Progressively more mild exacerbations on readministration of the drug suggest that desensitization may be possible in patients who exhibit hepatic abnormalities. Its low and sporadic incidence is typical of a hypersensitivity reaction. It is suggested that routine liver function tests should be undertaken at intervals during therapy. The occasional occurrence of Aldomet-induced liver disease is no contraindication to the use of this antihypertensive agent.
Measurement of Instantaneous Blood Flow Velocity and Pressure in Conscious Man with a Catheter-Tip Velocity Probe
Authors: GABE IVOR T. , GAULT JAMES H. , ROSS JOHN , MASON DEAN T. , MILLS CHRISTOPHER J. , SCHILLINGFORD JOHN P. , BRAUNWALD EUGENE
Published: June 2012

Twenty-three patients were investigated during diagnostic right and left cardiac catheterization with an electromagnetic catheter-tip velocity probe. The catheter contained a pressure lumen for simultaneous measurements of intravascular pressure. Average peak and mean blood velocities were 66 and 11 cm/sec in the ascending aorta, 57 and 10 cm/sec in the pulmonary artery, 28 and 12 cm/sec in the superior vena cava, and 26 and 13 cm/sec in the inferior vena cava. The velocity pattern in the ascending aorta was similar to that obtained by other methods. Positioning of the catheter in the ascending aorta required care; in one patient with aortic stenosis the recorded blood velocity pattern was unsatisfactory. In the pulmonary artery flicking of the catheter often produced artifacts in the records. The effect of deep respiration on blood velocity in the ascending aorta and pulmonary artery was studied. In the ascending aorta the highest velocities and stroke volumes were achieved during late expiration while in the pulmonary artery blood velocity and stroke volume were greatest in inspiration. In nine patients the cardiac outputs calculated from the product of mean velocity and radiologically measured cross-sectional area of the ascending aorta or pulmonary artery were compared with cardiac outputs determined by the indicator-dilution method; the correlation coefficient was 0.73. There were no complications, and the probe proved reliable.
A Study of the Human Heart as a Multiple Dipole Electrical Source
Authors: HOLT JOHN H. , BARNARD ANTHONY C.L. , LYNN M. STUART , KRAMER JOHN O.
Published: June 2012

The multiple dipole electrocardiographic (MDECG) method proposed earlier was evaluated further by testing its ability to diagnose and quantitate right ventricular hypertrophy (RVH). Two series of subjects were used. The first series consisted of patients with conditions giving a pressure overload of the right ventricle (RV), the RV systolic pressure (RVSP) being used to indicate the severity of RVH. The second series consisted of patients for whom a surgeon's visual estimate of RV size was available. A series of normal subjects was also used. For the first series a sensitivity of 85% for RVH diagnosis by MDECG was obtained, the specificity based on the normal series being 94%. The second, more inhomogeneous, series yielded a sensitivty of 75% and a specificity of 75%. This diagnostic performance was better than that obtained with conventional electrocardiographic or vectorcardiographic methods applied to the same patients.

To assess the quantitative ability of the MDECG, the results obtained for the first series were correlated with RVSP. A coefficient of determination for r
2
of 86% (standard error of RVSP estimate being 11 mm Hg) was obtained.
Evaluation of Myocardial Metabolism in Ischemic Heart Disease
Authors: GORLIN RICHARD
Published: June 2012

Metabolism of the human heart during myocardial infarction may be studied by means of arterial and coronary sinus catheterization at little risk, but definite inconvenience. Ischemia has been readily detected through myocardial production or release of lactate, potassium, hydrogen, and certain enzymes. These findings may be of help in identifying the presence of acute myocardial injury or infarction and in evaluation of applied therapy. Other studies, particularly of metabolized substrates, including oxygen, have been less rewarding. The patchy nature of coronary atherosclerosis and its partial compensation by collateral vessels renders coronary venous inflow nonuniform. This makes interpretation of the meaning of the concentration of substances contained within the coronary venous effluent extremely difficult. Multiple-site venous sampling is particularly helpful in overcoming this inherent defect in the method.
Cardiovascular Abnormalities Following Surgery for Left-to-Right Shunts
Authors: LUEKER RICHARD D. , VOGEL JOHN H. K. , BLOUNT S. GILBERT
Published: June 2012

Seventy-two patients with left-to-right shunts were studied an average of 5 years after operation. Persistent residual shunts occurred in 24 of the 72 patients and were unsuspected clinically in 11. While significant residual shunts were usually suspected in the group with ventricular septal defects (VSD), residual shunts in the group with atrial septal defects (ASD) were frequently unsuspected.

Abnormalities in pulmonary vascular reactivity as determined by excessive responses to hypoxia or exercise, or both, were noted in a significant number of cases of VSD and patent ductus arteriosus. Such unusual reactivity was not seen as frequently in the ASD group. Low cardiac output responses to exercise were noted in nearly half of the patients.

These studies illustrate the importance of long-term follow-up hemodynamic studies on postoperative patients with left-to-right shunts and indicate the necessity for exercise and hypoxia studies in addition to resting observations.
Coronary and Systemic Hemodynamic Effects of Cardiac Pacing in Man with Complete Heart Block
Authors: ROWE GEORGE G. , STENLUND ROGER R. , THOMSEN JAMES H. , TERRY WARD , QUERIMIT ALBERTO S.
Published: June 2012

Twelve subjects with an average age of 65.9 years who had complete heart block had cardiac output and coronary blood flow measured at three different rates of pacing. Cardiac output and calculated external work increased with rate from the slow to the intermediate rate, but declined at the fast rate. Even at the intermediate rate, cardiac output remained low as compared to standards for normal younger subjects. Coronary blood flow and left ventricular oxygen usage increased with cardiac rate. Cardiac efficiency, expressed as left ventricular work divided by left ventricular oxygen consumption, tended to decrease as cardiac rate rose; however, these changes were not statistically significant. Lactate consumption increased with rate, but changes in glucose and pyruvate consumption were not significant. Considering the circulatory system as a whole, the intermediate or normal resting rate was more efficient. At this rate the cardiac output and cardiac work were greatest, and the mixed venous oxygen content (which must reflect body tissue oxygenation) was highest, while the cardiac oxygen consumption and coronary blood flow were intermediate.
Ultrasound in the Diagnosis and Evaluation of Therapy of Idiopathic Hypertrophic Subaortic Stenosis
Authors: POPP RICHARD L. , HARRISON DONALD C.
Published: June 2012

Twenty patients with idiopathic hypertrophic subaortic stenosis (IHSS) were studied with cardiac echography. Eight of these patients were studied during left heart catheterization. The echographic pattern of mitral valve motion during systole was altered in a characteristic manner when hemodynamically significant left ventricular outflow obstruction was present in the eight patients studied at catheterization. The abnormal systolic pattern was abolished by spontaneous loss of outflow obstruction or loss of obstruction induced by beta-adrenergic blockade. An abnormal systolic mitral valve pattern was seen on the echogram in 17 of the 20 patients with proven IHSS. The abnormal pattern was lost after the institution of chronic propranolol therapy in one patient. The three patients not showing an abnormal systolic pattern were also taking propranolol. The pattern of mitral valve motion during diastole indicated an impaired rate of left ventricular filling. The basic abnormalities and variability in the degree of abnormality seen with echography of the left ventricular outflow tract are consistent with the proposed anatomy and pathophysiology of IHSS.
Coarctation of the Aorta and Other Late Sequelae of Administration of Thorium Dioxide (Thorotrast)
Authors: THIND GURDARSHAN S. , HARNER RICHARD N. , KASEFF LEON
Published: June 2012

Coarctation of the aorta secondary to a cervicomediastinal thorotrastoma developed in a 30-year-old man 25 years after carotid arteriography. Other local manifestations of the thorotrastoma included occlusion of the left common carotid artery and partial occlusion of the left vertebral and left subclavian arteries, bilateral recurrent laryngeal nerve paresis, periesophageal adhesions, and multiple traction diverticula of the esophagus. There was no evidence of hepatic neoplasm or malignant transformation of the thorotrastoma. The major risk for this patient in the future, even though small, would be the development of a malignant hepatic neoplasm. Surgery may be indicated if local symptoms, enlarging tumor mass, or signs of increasing aortic obstruction develop.
Heritable Q-T Prolongation Without Deafness
Authors: GARZA LEONCIO A. , VICK ROBERT L. , NORA JAMES J. , MCNAMARA DAN G.
Published: June 2012

The family, reported on, have a syndrome of prolonged Q-T interval, potentially fatal episodes of ventricular arrhythmias, and normal hearing. The direct familial transmission demonstrated in this pedigree is consistent with an autosomal dominant mode of inheritance. To protect other members of the family from the consequences of ventricular arrhythmia experienced by the irreversibly brain-damaged index patient, a series of physiologic investigations was undertaken on this patient in a search for a suitable prophylactic medical regimen. The attacks of ventricular arrhythmia were found to be precipitated by increase in systemic pressure, sinus tachycardia, and extrasystoles occurring in the supernormal phase of repolarization (R in T syndrome). Propranolol was demonstrated to be an effective agent in preventing the ventricular arrhythmia in the index case and in other family members. Since administration of the beta-adrenergic stimulator isoproterenol did not produce ventricular fibrillation, it is assumed that the action of propranolol in preventing ventricular arrhythmia is not mediated through beta-adrenergic blockade, but through its direct antiarrhythmic properties. The subject experienced no ill effect from the series of investigations.
Pervenous Pacing of the Specialized Conducting System in Man
Authors: NARULA ONKAR S. , SCHERLAG BENJAMIN J. , SAMET PHILIP
Published: June 2012

His bundle electrograms were recorded and A-V junction pacing was achieved in 30 patients by a pervenous electrode catheter technic. His bundle pacing was achieved in 26, and A-V node pacing in five patients. Conduction time from atrium to the His bundle (A-H time) and His bundle to ventricular activation (H-V time) were measured. During His bundle pacing, the pacing impulse to ventricular activation time (PI-R) was the same as the H-V time during normal sinus rhythm and remained constant at different pacing rates. With A-V node pacing, the PI-R interval was shorter than the conduction time from atrium to the ventricle (sum of the A-H and the H-V time) but longer than the H-V time, and there was progressive lengthening of PI-R interval, with increase in pacing rates. The QRS complex remained unchanged in all ECG leads with BH and A-V node pacing from that during normal sinus rhythm. During BH pacing, the retrograde Wenckebach phenomenon was demonstrated. Bundle of His pacing was used to establish a His bundle rhythm in a patient with complete heart block localized within the His bundle. BH pacing is of value for validation of His bundle electrograms and differentiation from that of right bundle branch. Clinically, this technic has proved extremely useful in definitive diagnosis of bilateral bundle-branch block in patients with right bundle-branch block and left axis deviation and infarction.
Skeletal Muscle Capillaries in Diabetics
Authors: VRACKO RUDOLF
Published: June 2012

Capillary sizes, the amounts of endothelium, pericytes, basal lamina (BL), and lumina were measured with planimeter on electron micrographs of 20 capillary cross sections from each of 40 skeletal muscle specimens obtained from any of eight specific body sites of 20 diabetics. While the capillaries in the distal abdomen and the proximal thigh do not have thickened BL, those in the muscles of mid-abdomen, chest wall, hand, mid-thigh, mid-lower leg, and foot have significantly increased amounts of BL. The remaining parameters differ among body sites, generally following a pattern established earlier for the skeletal muscle capillaries of nondiabetics. Because of the focal and regional distribution of BL thickening and because it occurs also in nondiabetics, it is concluded that BL thickening is a common but not characteristic feature of diabetes mellitus. A possible mechanism which may lead to BL thickening is proposed and discussed.
Acute Alterations of Body Composition after Open Intracardiac Operations
Authors: PACIFICO ALBERT D. , DIGERNESS STAN , KIRKLIN JOHN W.
Published: June 2012

The body composition of patients with heart disease is acutely altered by surgical intervention. Interrelations and causes of the alterations have not been clear. Twenty patients were studied preoperatively and again 2 to 4 days after open intracardiac operations. In nine, measurements were made of the volumes of total body water, extracellular water, plasma, and red cells, and of the amounts of total exchangeable sodium and potassium. In an additional four patients total exchangeable sodium and potassium were measured, and in another seven only exchangeable sodium was measured. Calculations were made of the intracellular and extracellular distribution of water and potassium. The significant changes (
P
< 0.05) occurring during the interval between studies were increase in extracellular water (7%), interstitial water (12.5%), and exchangeable sodium (9.4%), decrease in total exchangeable potassium (8.5%) and amount (8.7%), and concentration (6.9%) of calculated intracellular potassium. Uptake of sodium and water by the patient during cardiopulmonary bypass and postoperative loss of intracellular potassium with its secondary renal excretion are postulated as being etiologic. These findings imply that sodium intake in the early postoperative period should be low, water intake no more than urinary and insensible losses, and that potassium should be administered.
The Changes in the Circulation After Birth
Authors: RUDOLPH ABRAHAM M.
Published: June 2012

Circulatory changes at birth have a profound influence on the physiology of the circulation in normal infants and those with congenital heart disease. Since the concept that cardiac defects are fixed entities is being superseded by an appreciation of the changing nature of physiologic disturbances and their clinical consequence, the course and distribution of the fetal circulation with the influences of the major changes at birth, including changes in pulmonary vascular resistance, and closure of the ductus arteriosus and foramen ovale, require study. This lecture traces these and other changes and discusses their influences on congenital heart disease.
Analysis of the A-V Conduction Defect in Complete Heart Block Utilizing His Bundle Electrograms
Authors: NARULA ONKAR S. , SCHERLAG BENJAMIN J. , JAVIER ROGER P. , HILDNER FRANK J. , SAMET PHILIP
Published: June 2012

Twenty-one patients with complete heart block (CHB) were studied by recording His bundle (BH) electrograms. The site of block was localized proximal or distal to the site at which the BH electrogram was recorded. Eighteen patients had block distal to the recorded BH deflection. One of these 18 patients had a narrow QRS complex indicating block within the His bundle; the other 17 had wide QRS complexes probably due to bilateral bundle-branch block. The three patients with block proximal to the His bundle are examples of A-V nodal block or block in the uppermost portion of the BH. Two of these three had normal QRS complexes; the third with a left bundle-branch block pattern demonstrated that during CHB the ECG criteria for the localization of the site of block are not dependable. The conduction time from the atrium to the BH (A-H time) was measured in the 18 patients with CHB distal to the BH and was within the normal range. With atrial pacing there was progressive lengthening of the A-H time, and Wenckebach phenomena were demonstrated in some cases. The conduction time from the His bundle to the ventricles (H-V time) in patients with block proximal to the His bundle was also within the normal range. Bilateral bundle-branch block was probably the mechanism of block in the majority of the patients with CHB; this emphasizes the clinical significance of ECG patterns indicating bilateral bundle-branch block during normal sinus rhythm with 1:1 A-V conduction.
Left Ventricular Systolic Time Intervals as Indices of Postural Circulatory Stress in Man
Authors: STAFFORD R. W. , HARRIS W. S. , WEISSLER A. M.
Published: June 2012

The effects of graded increments of passive head-up tilt on the duration of the systolic time intervals corrected for heart rate were investigated in 15 normal subjects. Head-up tilt caused a prolongation of the pre-ejection period and a shortening of the left ventricular ejection time, while total electromechanical systole diminished minimally. The lengthening of the pre-ejection period and abbreviation of the left ventricular ejection time increased progressively with stepwise increments of head-up tilt. The application of venous occlusive tourniquets produced changes in the systolic intervals directionally similar to those observed with head-up tilt. In contrast to the normal subjects, three patients with congestive heart failure demonstrated no change in the systolic time intervals during head-up tilt. After diuresis in two of the patients with heart failure, the responses of their systolic time intervals to head-up tilt returned toward normal.
Percutaneous Right and Left Heart Catheterization in Children
Authors: SIMOVITCH HARVEY , HOHN ARNO R. , WAGNER HENRY R. , VLAD PETER , SUBRAMANIAN S. , LAMBERT EDWARD C.
Published: June 2012

One thousand patients, ranging in age from 4 months to 26 years, underwent percutaneous catheterization of the femoral artery and femoral vein. Cardiac catheterization was combined with selective angiocardiography in all patients.

The catheter entered the right ventricle in 972 of 990 patients (98%) and the left ventricle in 832 of 856 (97%), including 82 of 89 patients (92%) with aortic stenosis.

There were no deaths, perforations of the heart, or loss of tissue. The peripheral pulse was decreased in 6% (49 of 856) and absent in 2% (17 of 856). Other complications included two uneventful perforations of the aortic arch, two lacerations of the femoral artery, three lacerations of the femoral vein, a false aneurysm of the femoral artery, and a cerebrovascular accident.

Our findings indicate that, in children more than 2 years old and weighing more than 10 kg, the percutaneous method is safe, informative, and associated with less arterial circulatory complications than the approach from the surgically exposed artery.
Cardiac Performance After Diagnostic Coronary Arteriography
Authors: RAHIMTOOLA SHAHBUDIN H. , GAU GERALD T. , RAPHAEL MAURICE J.
Published: June 2012

Cardiac performance was assessed before and after diagnostic coronary arteriography in 19 patients with heart disease. There was no significant change in cardiac output, heart rate, stroke volume, hemoglobin, hematocrit, and mean systemic arterial pressure. Left ventricular (LV) filling pressure and mean pulmonary artery pressure increased temporarily. The increased left ventricular filling pressure was accompanied by an increase of LV work performed in a few patients; in the remainder the left ventricle performed less work.

In four dogs, selective left coronary arteriography resulting in increased ventricular filling pressure, was accompanied by an increase of left ventricular end-diastolic (V
ED
) and stroke volumes; the ejection fraction and heart rate remained unchanged.

If the animal studies (increased V
ED
accompanying increased ventricular filling pressure) can be applied to patients with heart disease, the alteration of left ventricular function can be considered on the basis of the Frank-Starling mechanism. To cope with the temporary depression of its function, the left ventricle of patients with heart disease utilized the Frank-Starling mechanism resulting in an adequate (essentially unchanged) cardiac output from an increased left ventricular filling pressure. The normal left ventricle of the dog, stressed more than is appropriate clinically, shows an increased stroke volume accompanying the increased end-diastolic volume.
Effect of Potassium on A-V Conduction
Authors: FISCH CHARLES
Published: June 2012

"When the potassium is injected slowly, after a time the heart gradually slows to perhaps half its normal rate, the auricle and ventricle being markedly dilated but still contracting synchronously. This is an example of sinus slowing, and is probably due to the direct action of the salt upon what Lewis has termed the `pace-maker' of the heart; it is not due to stimulation of the vagus endings, since it is still produced after administration of atropine. . . .

"In other cases an
abrupt
slowing of the pulse rate occurs, due to dissociation of the auricular and the ventricular rhythms, a condition of 2:1 or of complete heart block being produced. This dissociation is sometimes seen in a heart that is in quite good condition and, upon discontinuing the injection of potassium salts, recovery soon takes place. It cannot be produced with any degree of certainty; since marked sinus slowing, stoppage in diastole, or ventricular fibrillation frequently ensue without this type of heart block being manifested. . . .

"In the present state of our knowledge it is legitimate to infer from these results that the block is due to a depression of the conductivity of the auriculoventricular connections from the direct action of the potassium salts upon the musculature. The block is produced in the hearts of animals that have been treated with atropine, so that stimulation of the vagus mechanism is not an essential factor."—
Mathison.
1
Diminished Forearm Arteriolar Dilator Capacity Produced by Mineralocorticoid-Induced Salt Retention in Man
Authors: ZELIS ROBERT , MASON DEAN T.
Published: June 2012

The mechanism of the increased stiffness of peripheral vessels in patients with congestive heart failure (CHF) is unknown. It was considered that an increased sodium (Na
+
) content of peripheral vessels, shown in experimental CHF, might lead to diminished arteriolar dilator capacity. Thus, Na
+
retention was induced in six normal volunteers by the daily oral administration of 0.2 mg of fludrocortisone acetate (F) and 10 g NaCl for 1 week. This induced a weight increase of 3.1 lb and increased serum Na
+
and decreased serum potassium concentrations (
P
< 0.02). The peak reactive hyperemia blood flow (RHBF) was measured plethysmographically in the forearm before and after treatment. Upon restoration of the circulation after 1, 5, and 10 min of ischemia the peak RHBF was 21.8, 33.1, and 34.9 ml/min/100 ml before administration of F and NaCl but was reduced to 19.6 (
P
> 0.2), 28.6 (
P
< 0.02), and 24.4 (
P
< 0.02) ml/min/100 ml by treatment. Thus, steroid-induced salt retention leads to diminished vascular compliance. Furthermore, it is suggested that increased vascular Na
+
content is causally related to the vascular stiffness abnormality characterostic of CHF.
The Influence of Changes in Blood Volume on Angina Pectoris
Authors: PARKER JOHN O. , CASE ROBERT B. , KHAJA FAREEDUDDIN , LEDWICH J. RODNEY , ARMSTRONG PAUL W.
Published: June 2012

Angina pectoris was precipitated in 15 patients with coronary artery disease by the technic of right atrial pacing. This was accompanied by hemodynamic evidence of impaired left ventricular function. In eight patients, while pacing was continued, a phlebotomy averaging 276 ml was carried out and in all but one patient angina was relieved and ventricular function returned to normal. Phlebotomy was accompanied by a decline in cardiac index (9.6%) and left ventricular filling pressure, but no change in brachial artery mean pressure, tension-time index, or dp/dt. With reinfusion of blood, angina returned in all but one patient and there was a rise in left ventricular end-diastolic pressure but no change in cardiac index, brachial artery pressure, tension-time index, or dp/dt. In seven patients alterations of blood volume were carried out between three 9-minute periods of atrial pacing and similar observations were obtained. The observations indicate that phlebotomy exerted its beneficial effect through a reduction in left ventricular volume, and it is suggested that this may be the primary mode of action of nitroglycerin.
Estimation of Aortic Regurgitation by Diastolic Pulse Wave Analysis
Authors: JUDGE TERRANCE P. , KENNEDY J. WARD
Published: June 2012

To test the hypothesis that the fall in supravalvular aortic diastolic pressure is relative to the severity of the regurgitant flow in aortic regurgitation, 27 patients with isolated aortic regurgitation, 23 patients with combined aortic regurgitation and stenosis, and 15 normal subjects were studied. Diastolic pulse pressure (pressure at the dicrotic notch minus pressure at end diastole) and the diastolic slope (line constructed through the dicrotic notch and end diastole) were measured.

A highly significant correlation was found between the regurgitant flow in isolated aortic regurgitation and the diastolic pulse pressure when corrected for heart rate (r = 0.82,
P
< 0.001). The diastolic slope related similarly to the regurgitant flow (r=0.71,
P
< 0.001). There was no significant relationship, however, in the presence of combined aortic stenosis and regurgitation. Aortic pressure at end diastole and pulse pressure correlated poorly with either isolated aortic regurgitation or combined aortic valve disease.

An electrical analog circuit was used to help explain these findings.
Familial Atrial Septal Defect with Prolonged Atrioventricular Conduction
Authors: BIZARRO RAUL O. , CALLAHAN JOHN A. , FELDT ROBERT H. , KURLAND LEONARD T. , GORDON HYMIE , BRANDENBURG ROBERT O.
Published: June 2012

Atrial septal defect (ASD) of the fossa ovalis type was found in 16 members of one family and confirmed in 15 members at autopsy or surgery or by cardiac catheterization. Sinus rhythm was present in 12 affected members, 11 of whom had electrocardiographic evidence of prolonged atrioventricular (A-V) conduction. Five other family members without ASD also had prolonged A-V conduction. The pedigree chart suggests that the syndrome ASD with prolonged A-V conduction is the manifestation of a single mutant autosomal gene with dominant effect, a high degree of penetrance, and some variation in expressivity. Earlier reports of familial ASD showing the autosomal-dominant pattern of inheritance reveal a similar frequency of prolonged A-V conduction among affected persons. The great majority of cases of ASD are sporadic, with little likelihood of recurrence in subsequent sibs or children. We suggest, however, that when ASD of the fossa ovalis type is accompanied by prolonged A-V conduction, the genetic prognosis may be drastically changed to a risk of almost 50% that the condition will recur in subsequent sibs or children of affected persons.
Juxtaposition of Atrial Appendages Associated with Normally Oriented Ventricles and Great Arteries
Authors: BECKER ANTON E. , BECKER MIES J.
Published: June 2012

A case is reported of a stillborn infant in whom both atrial appendages lay to one side of the great arteries, so-called juxtaposition of the atrial appendages.

The unusual features of the case reported are twofold. First, both atrial appendages lay to the right of the great vessels while, more commonly, juxtaposed atrial appendages lie to the left of the aorta and pulmonary trunk.

Second, in our case the great vessels were normally related and no major intracardiac malformations were present (only an atrial septal defect and a bicuspid pulmonary valve), while, more commonly, the great vessels are transposed and major intracardiac malformations are associated.
Long-Term Thiazide Therapy in Essential Hypertension
Authors: TARAZI ROBERT C. , DUSTAN HARRIET P. , FROHLICH EDWARD D.
Published: June 2012

Plasma volume (RIHSA) and peripheral plasma renin activity (Pickens' method) were measured in eight essential hypertensive patients treated with thiazide diuretics alone for periods ranging from 6 to 24 months. Treatment was then stopped and measurements repeated at weekly intervals for a month. During the first week of discontinuance, body weight and plasma volume rose in all (
P
< 0.001 for both), while peripheral plasma renin activity fell from 3.66 to 1.04 ng/ml (
P
< 0.005), and serum sodium concentration was practically unchanged. Over the next 3 weeks, both plasma volume and body weight gradually fell from the high first week "rebound" values to plateau at levels higher than those obtained during treatment (2741 vs. 2567 ml,
P
< 0.001 and 76.1 vs. 74.7 kg,
P
< 0.001, respectively). At the same time, peripheral plasma renin activity remained stable and markedly lower than during treatment (
P
< 0.001), while blood pressure gradually rose. Extracellular water (ECW) was measured serially (radiobromine) in five patients; in all, body weight variations were completely accounted for by changes in ECW, and ratio of plasma to interstitial fluid volume remained stable. These data indicate that blood pressure reduction by longterm thiazide therapy was associated with persistent plasma volume contraction and occurred despite increased peripheral renin activity. There was no evidence for chronic intracellular dehydration, and variations in peripheral renin activity were related to changes in plasma volume and not to serum sodium concentration.