bluuebunny/crossref_metadata_2025 huggingface dataset:
Truncal Valve Abnormalities in Infants with Persistent Truncus Arteriosus
Authors: GELBAND HENRY , VAN METER SHARON , GERSONY WELTON M.
Published: June 2012

Clinical data on 12 patients under 6 months of age are presented together with the necropsy evidence of truncus arteriosus. Five patients had normal truncal valves and seven had markedly deformed and incompetent valves. Among the group of infants with truncal valve insufficiency, the cause of death was refractory congestive heart failure in each instance, whereas the patients with normal truncal valves succumbed from other causes.

Pathologic examination of the abnormal truncal valves revealed cusps which were thickened by fibrous nodules. Combined heart-lung weight in patients with deformed truncal valves had a mean increase of 85% above normal values, while in the group of patients with normal truncal valves the mean increase was 17%. Similar results were observed when liver weights were compared.

The major clinical findings among the group of patients with truncal insufficiency were bounding peripheral arterial pulses, early diastolic decrescendo murmurs, and congestive heart failure which was refractory to medical treatment and, in one instance, surgical palliation. It is suggested from the data that deformities of the truncal valves are a primary cause of early mortality among infants with truncus arteriosus.
Observations on the Natural History of Pulmonary Artery Coarctations
Authors: ELDREDGE W. JAY , TINGELSTAD JON B. , ROBERTSON LOUISE W. , MAUCK H. PAGE , MCCUE CAROLYN M.
Published: June 2012

Seventeen of a series of 70 patients with coarctation of the pulmonary artery underwent serial cardiac catheterizations from 2.0 to 12.4 years apart. Main pulmonary artery pressures were measured in all patients, and the values from each study were compared. A change in pressure in the main pulmonary artery was considered to reflect a change in the distal pulmonary artery obstruction. Seven patients with no other associated cardiac defects, four with associated pulmonary valve disease, and six with associated left-to-right shunts all demonstrated little change in main pulmonary artery pressures between the two studies. These data substantiate the observation that pulmonary artery coarctations represent a nonprogressive form of congenital heart disease in which the severity of obstruction to pulmonary blood flow does not increase with age.
Metabolic Response during Impending Myocardial Infarction
Authors: OLIVER M. F.
Published: June 2012

The immediate local metabolic response of the myocardium to acute regional ischemia is determined by an interaction of various influences. These include: (1) the extent of and the variability in reduction of blood flow; (2) the degree and persistence of hypoxia; and (3) the effects of local release of catecholamines, particularly in relation to loss of intracellular potassium.

The subsequent metabolic response of the myocardium is partly dependent on the degree of impairment locally of normal myocardial metabolism and partly on the systemic reaction to increased catecholamine activity and hence on: (1) adipose tissue lipolysis; (2) hepatic and muscle glycogenolysis; (3) insulin suppression; and (4) growth hormone and cortisol activity. These determine the extent of the uptake from blood of FFA and glucose by the ischemic myocardium.

There is increasing evidence that high arterial concentrations of FFA can depress myocardial performance by leading to ventricular arrhythmias and decreased contractility. This effect probably depends on a critical interaction between the local concentration of FFA, catecholamines, and hypoxia.

Metabolic intervention in the management of heart attacks should accordingly be directed toward reducing mobilization of adipose tissue FFA and increasing myocardial glycolytic activity.
Glucagon in Heart Failure and in Cardiogenic Shock
Authors: LVOFF ROBERT , WILCKEN DAVID E. L.
Published: June 2012

Intravenous glucagon, in doses of 2.5-15 mg/hour, was administered to 50 patients for periods of 1-7 days. Forty patients had either intractable heart failure or cardiogenic shock or both; the remaining 10 had less severe heart disease. In all patients glucagon was added to conventional therapy. Twenty-two of the 40 with very severe heart failure showed a clinical improvement, and 18 were discharged from the hospital; 16 of the 18 patients who did not respond died in the hospital. Only two of the 10 with less severe heart disease improved with glucagon but all could be discharged from the hospital. Glucagon did not initiate or aggravate a tendency to arrhythmias in any of the 17 patients with acute myocardial infarction. In two patients with bradycardia and cardiac failure due to beta-adrenergic blocking drugs, glucagon increased heart rate and there was clinical improvement in heart failure. However, there was no effect in two patients with digitalis-induced nodal bradycardia and heart failure. Nausea was the most troublesome side effect and this could usually be controlled by intramuscular prochlorperazine (Stemetil) which was given routinely before the infusion in all except postoperative patients and repeated as required during the infusion. The results show that glucagon has a definite place in the management of patients with severe heart failure when used as an adjunct to conventional therapy.
Complications of Selective Percutaneous Transfemoral Coronary Arteriography and their Prevention
Authors: GREEN GERALD S. , MCKINNON C. MALCOLM , RÖSCH JOSEF , JUDKINS MELVIN P.
Published: June 2012

Complications encountered during a typical 12-month period of routine work with the Judkins percutaneous transfemoral method of selective coronary arteriography are reviewed. In 445 examinations, 20 complications (16 local and four cardiac) occurred. Local complications included nine delayed hemorrhages, five thromboses of femoral arteries, and two peripheral emboli. Cardiac complications included one ventricular fibrillation, one significant bradyarrhythmia, and two myocardial infarctions. Causes of individual complications are analyzed and means for their prevention discussed. Guidelines of the procedure are proposed to minimize the complications of selective coronary arteriography. Emphasis is placed on patient evaluation, preparation for the procedure, and meticulous examination technique.
Conduction Disturbances Located within the His Bundle
Authors: SCHUILENBURG REINIER M. , DURRER DIRK
Published: June 2012

Four patients are described with different degrees of conduction disturbance within the His bundle. In one patient with a Mobitz type II atrioventricular (A-V) block with normal QRS complexes the blocked atrial beats were followed by a His potential. Since the QRS complexes of the conducted beats were completely normal, the site of the block was thought to be in the distal part of the His bundle. In the other three patients with a 2:1 A-V block, a nearly complete A-V block, and a complete A-V block, two distinct His potentials could be discerned, one (H) following each atrial beat, the other (H') preceding each ventricular activation. In the patient with 2:1 A-V block a Wenckebach phenomenon within the His bundle could be produced at certain atrial driving rates. Impulse conduction through the A-V node was normal in all four cases, as could be concluded from the effect of increased atrial driving rate and of accurately timed atrial premature beats. The site of the block could not be predicted from the conventional electrocardiogram.
Tachyarrhythmias in Myocardial Infarction
Authors: DESANCTIS ROMAN W. , BLOCK PETER , HUTTER ADOLPH M.
Published: June 2012

Tachyarrhythmias occur in about one third of patients with acute myocardial infarction (MI), and may precipitate serious consequences when they arise. Mechanisms of arrhythmogenesis in MI are imperfectly understood, but five categories of factors contributing to ectopic tachycardias are discussed. These include metabolic, anatomic, autonomic, hemodynamic, and iatrogenic causes. Each of the atrial, junctional, and ventricular tachyarrhythmias is briefly considered, and therapy is outlined.

Prevention of tachyarrhythmias and prompt treatment when they occur have substantially reduced mortality in acute MI, and constitute a primary objective of coronary care. However, better understanding of mechanisms of arrhythmogenesis, better systems of automated monitoring, and better modes of therapy, especially antiarrhythmic drugs, are urgently needed.
Effect of Oxygen Breathing on Pacing-Induced Angina Pectoris and other Manifestations of Coronary Insufficiency
Authors: HORVAT MATIJA , YOSHIDA SHINJI , PRAKASH RAVI , MARCUS HAROLD S. , SWAN H. J.C. , GANZ WILLIAM
Published: June 2012

Eleven patients with arteriographically confirmed coronary artery disease and normal arterial oxygen saturation were studied. The angina threshold was determined first by successive elevation of heart rate at increments of 10 and 5 beats/min by right atrial pacing while the patients were breathing air via a close-fitting mask. The mask was then connected to an oxygen tank without the patient's knowledge. After 5 min of oxygen breathing, the heart rate was again raised to the previously determined threshold level. In nine of 11 patients angina did not recur. The absence of angina was associated with improvement in myocardial lactate extraction from -17 ± 15 to +18 ± 10% (
P
< 0.025), in S-T abnormalities in six of seven patients, and in pulsus alternans in three of five patients.

The pacing rate was then raised at increments of 5 beats/min until angina recurred. With oxygen breathing, angina developed at higher pacing rates (129 ± 7 beats/min with air and 137 ± 6 beats/min with oxygen, on the average;
P
< 0.005), at higher rate-pressure product (18.0 ± 0.8 and 19.5 ± 0.9 x 10
3
mm Hg/min, respectively;
P
< 0.01), and at higher left ventricular oxygen consumption (21.3 ± 1.1 and 24.6 ± 1.1 ml/min, respectively;
P
< 0.005). The results indicate that oxygen breathing permits the heart to do more work before coronary insufficiency develops.
Cerebral Blood Flow during Carotid Endarterectomy
Authors: WALTZ ARTHUR G. , SUNDT THORALF M. , MICHENFELDER JOHN D.
Published: June 2012

Cerebral blood flow (CBF) was measured during 28 carotid endarterectomies in 25 patients, by injection of
133
Xe into the exposed internal carotid artery (ICA). Twenty-three patients had episodic cerebral or retinal ischemia and five had neurologic deficits before operation. Initial CBF values were variable. Increases of Pa

Co
Co2

caused CBF to increase in four of six patients, to increase slightly in one, and to decrease in one. In each of 19 procedures, CBF decreased during surgical occlusion of the ICA, 11 times to less than 30 ml/100 g/min, but absence of postoperative worsening indicated that decreased ICA blood flow is not a major risk of the procedure; embolization from the site of operation may be a greater threat to the patient. CBF increased after 14 endarterectomies, perhaps due to failure of autoregulation or to reactive hyperemia. Measurements of jugular PV

o
o2

and lactate concentration were of little value.
Heart Failure Complicating Acute Myocardial Infarction
Authors: WOLK MICHAEL J. , SCHEIDT STEPHEN , KILLIP THOMAS
Published: June 2012

Congestive heart failure (CHF) occurs in about one half of all patients with acute myocardial infarction and is a manifestation of acute alterations in left ventricular function. In the present study CHF is defined on clinical grounds, according to the presence and extent of bilateral pulmonary rales. An accompanying S
3
ventricular gallop was heard in 58% of our patients with heart failure initially, but it disappeared eventually in the majority. Dilatation of pulmonary veins and blurring of pulmonary vascular markings are useful roentgenographic signs which reflect elevations in left heart filling pressure. At times the earliest indicators of heart failure, these findings appear in general to be less sensitive than the physical examination in diagnosing CHF. Although stroke volume is decreased with CHF, cardiac index is generally maintained by increased heart rate. Left ventricular minute work and stroke work are significantly decreased, while left ventricular end-diastolic pressure is significantly increased, in patients with CHF complicating acute myocardial infarction. Arterial hypoxemia is common and the degree of arteriovenous shunting is roughly proportional to the elevation of left ventricular filling pressure. The mortality of patients with CHF is approximately three times that of patients with acute myocardial infarction and no complications. Diuretic therapy is safe and effective. Attention is called to the probability that the use of digitalis preparations in the early hours following myocardial infarction is hazardous. Furthermore, hemodynamic benefit from digitalization in the early postinfarction period remains unproven.
Localization of Ventricular Irritability by Epicardial Mapping
Authors: KASTOR JOHN A. , SPEAR JOSEPH F. , MOORE E. NEIL
Published: June 2012

Epicardial mapping technics were used to locate the origin of ventricular ectopic beats produced by pacing and by the administration of ouabain and acetylstrophanthidin in pentobarbital-anesthetized open-chest dogs. The sequence of epicardial depolarization was determined with close bipolar reference and roving electrodes. The wave of excitation spread in concentric manner from driven points with the origin having the earliest time. Nonparasystolic unifocal ventricular tachycardia (UVT) was then aroused in nine dogs with ouabain or acetylstrophanthidin. Plunge electrodes were inserted for recording and stimulating of bundle of His and Purkinje fibers. Earliest epicardial ventricular activation of the UVT beats always occurred at or near the apex of the left ventricle. Purkinje fiber (PF) spikes from the region of earliest epicardial depolarization appeared just prior to ventricular activation. Pacing at this point produced QRS configuration almost identical to that during UVT. His bundle pacing normalized QRS configuration and suppressed UVT. Isolated right ventricular and left ventricular PF were perfused in the same tissue bath for microelectrode impalement. Infusion of ouabain increased the rate of automatic discharge of left ventricular PF before those from the right ventricle in each of five preparations. These studies suggest that digitalis-induced unifocal ventricular tachycardia originates below the His bundle from Purkinje tissue supplying the left ventricle and demonstrate that automaticity of canine PF from the left ventricle is preferentially enhanced by ouabain.
Ouabain Pharmacokinetics in Dog and Man
Authors: SELDEN RICHARD , SMITH THOMAS W. , Findley William
Published: June 2012

The pharmacokinetics of the relatively polar and rapidly acting cardiac glycoside ouabain (G-strophanthin) were studied in dogs and human subjects by the use of a newly devised radioimmunoassay technic. This method had high specificity and a sensitivity of less than 0.1 ng of ouabain per ml of plasma or urine. After administration of a single intravenous dose, the plasma ouabain concentration fell rapidly in both dogs and humans. After 7 hours, a phase of exponential decline was reached which had a half-life of 18 hours in dogs and 21 hours in normal human subjects. Repeated intravenous administration of ouabain to human subjects for 9 consecutive days resulted in the establishment of a plateau of plasma concentration and urinary excretion after 4-5 days, confirming plasma and urinary half-lives in the 19-24-hour range. The mean ratio of renal clearance of ouabain to that of creatinine was 0.81 in the human subjects. The plasma half-life of ouabain determined in these studies is in good agreement with previous observations of the half-life of dissipation of positive inotropy and of slowing of ventricular response to atrial fibrillation after ouabain administration.
Cardiac Rupture during Myocardial Infarction
Authors: NAEIM FARAMARZ , DE LA MAZA LUIS M. , ROBBINS STANLEY L.
Published: June 2012

Forty-four cases of myocardial infarction with cardiac rupture, 88 cases of unruptured myocardial infarction, and 88 cases without myocardial infarction were studied retrospectively. The incidence of cardiac rupture in cases with acute myocardial infarction alone was 5.5% while in hearts having both healed and acute myocardial infarction the incidence was 2.3%. One instance of cardiac rupture was encountered in a heart having only a healed myocardial infarction with subsequent aneurysmal dilation of the healed infarct. Although females represented only 37% of the population having acute myocardial infarction in this institution, they accounted for 55% of the cases of cardiac rupture. On the average the hearts which ruptured following myocardial infarction were lighter and thinner than in the control group of patients having infarction without rupture. Among the clinical correlates possibly associated with postinfarction rupture the most significant finding in the present study is the presence of postinfarction hypertension. In the group of cases with cardiac rupture this was present in 40% while in the control group not having suffered cardiac rupture the comparable figure was 14%. A history of diabetes was found in 18% of the cases of myocardial infarction not having suffered cardiac rupture. A similar history was found in only 9% of the cases having a postinfarction cardiac rupture. This latter incidence is identical with the frequency of diabetes mellitus in the general autopsy population. There is a suggestion that early and severe atherosclerosis may cause earlier heart disease and when infarction occurs provide some protection against rupture. Of interest among the 44 cases of cardiac rupture, none of the patients had cirrhosis, in striking contrast to the 11% incidence of this condition in our general autopsy population.
Interstitial Pulmonary Edema
Authors: CHAIT ARNOLD
Published: June 2012

The diagnosis of interstitial pulmonary edema can be made only on the basis of the chest roentgenogram. This often is the first sign of left heart failure, which may be completely unsuspected clinically in the absence of alveolar edema. Kerley lines, or septal lines, are the most familiar roentgen sign of this condition. Other, more common findings include: perivascular and peribronchial cuffing, subpleural thickening, perihilar haze, and a generalized loss of translucency of the lung. Meticulous roentgen technic is essential for recognition of these subtle signs.
Left Ventricular Papillary Muscles
Authors: ROBERTS WILLIAM C. , COHEN LAWRENCE S.
Published: June 2012

The left ventricular papillary muscles appear to be the last portions of the heart to be perfused by coronary arterial blood. As a consequence they are sensitive anatomic markers of myocardial ischemia. Foci of necrosis or fibrosis therefore are commonly seen in these structures, particularly the posteromedial papillary muscle, which has a poorer blood supply than does the anterolateral muscle. Coronary arterial luminal narrowing is the most common cause of necrosis or fibrosis of the left ventricular papillary muscles. Other conditions, all associated with inadequate cardiac output, which may produce these lesions include left ventricular outflow tract obstruction, especially that resulting from congenitally malformed aortic valves, acute valvular regurgitation (infective endocarditis), various cardiomyopathies, and primary endocardial fibroelastosis with or without anomalous origin of one or both coronary arteries from the pulmonary trunk. Various infiltrative diseases, including inflammation (Aschoff bodies, sarcoid, abscesses), amyloid, iron, and neoplasms, also may involve the papillary muscles. Their most common congenital malformation is the parachute or single papillary muscle. Fibrosis or necrosis of adjacent left ventricle free wall without involvement of the papillary muscles themselves may simulate clinically "papillary muscle dysfunction." The anterior papillary muscle of the right ventricle is frequently affected by conditions which also affect the left ventricular papillary muscles. Whether or not necrosis or fibrosis of the right ventricular papillary muscle causes tricuspid regurgitation, however, is unknown at present.
An Indirect Method for Evaluation of Left Ventricular Function in Acute Myocardial Infarction
Authors: AGRESS CLARENCE M. , WEGNER STANLEY , FORRESTER JAMES S. , CHATTERJEE KANU , PARMLEY WILLIAM W. , SWAN H. J. C.
Published: June 2012

An indirect estimate of the contractility index, max LV dP/dt/LVEDP, has been examined in 32 patients following acute myocardial infarction (AMI) and in three patients with acute coronary insufficiency (ACI). The index was derived from arterial diastolic pressure (DP) obtained by sphygmomanometer, left ventricular filling pressure (LVFP) obtained by pulmonary artery balloon catheter, and preejection period (PEP) determined from the phonocardiogram, carotid pulse, and ECG. These data were used in the relation (DP-LVFP)/PEP/LVFP (i.e., ΔP/Δt/LVFP) as an approximation of the direct contractility index max dP/dt/LVEDP. While measurements of PEP, DP, and LVFP used independently were not useful in distinguishing patients grouped in surviving AMI, nonsurviving AMI, and ACI categories, the ΔP/Δt/LVFP index showed marked separation of these groups. Because of the simplicity of measurement and minimal intravascular intervention, the index provides a safe and practical means of assessing the degree of left ventricular dysfunction in patients with AMI.
Total Anomalous Pulmonary Venous Drainage in Infants
Authors: BEHRENDT D. M. , ABERDEEN E. , WATERSON D. J. , BONHAM-CARTER R. E.
Published: June 2012

Thirty-seven infants with total anomalous pulmonary venous drainage have been operated upon at The Hospital for Sick Children, Great Ormond Street, London, with 13 survivors. Most were rapidly deteriorating when admitted. Cardiac catheterization, angiography, and operation were urgently undertaken to achieve the maximum salvage. Physical examination, plain radiography, and electrocardiography were insufficient for accurate diagnosis. Survival was closely related to the degree of pulmonary hypertension, which was dependent on the type of anomalous venous drainage and the presence of pulmonary venous obstruction. The prognosis was good for patients over 3 months of age, especially those without pulmonary venous obstruction, provided that they arrived in the hospital in reasonable condition. The best survival rate, nine of 11 cases, was achieved in those patients between 3 and 12 months of age with supracardiac drainage.
Common Pulmonary Vein Atresia
Authors: HAWKER RICHARD E. , CELERMAJER JOHN M. , GENGOS DON C. , CARTMILL TIMOTHY B. , BOWDLER J. DENBY
Published: June 2012

Two cases of common pulmonary vein atresia (CPVA) are presented. In one, the diagnosis was suspected on clinical grounds, and in both it was c onfirmed by cardiac catheterization and angiocardiography. Surgical correction was attempted unsuccessfully in one. Prompt identification of the defect followed by immediate operation, using a technic of profound hypothermia and circulatory arrest, offers hope of successful correction in this rare anomaly.
The Conotruncus
Authors: GOOR DANIEL A. , EDWARDS JESSE E.
Published: June 2012

A primitive form of double-outlet right ventricle is described clinically and anatomically. A long tubular conus, arising exclusively from the right ventricle emptied into the transposed great vessels. Together with the presence of A-V canal malformation this heart represented a developmental arrest in the embryonic stage of the bulboventricular loop seen in horizon XV. Diagnosis is made on the basis of right ventricular angiography and theoretically, if this lesion is isolated, this conus malformation is surgically correctable.
Pulmonary Edema
Authors: FISHMAN ALFRED P.
Published: June 2012

The pathogenesis of clinical pulmonary edema is considered in the light of recent physiologic and anatomic insights. Pulmonary edema is depicted as a persistent imbalance between the forces that move water into the extravascular spaces and the biologic devices for its removal. In the normal lung, intricate anatomic arrangements coupled with elaborate physiologic mechanisms maintain the gas-exchanging surfaces moist and free of excess protein. A transient excess of water in the interstitial space is associated with an increase in lymphatic flow. Should the excess rate of formation persist or increase, pulmonary edema may become manifest clinically, first as interstitial edema and then as alveolar and airway edema. The distribution of edema within the lung may be nonuniform, often favoring the central portions early in its genesis but later redistributing under the influence of gravity. A critical limitation in anatomic design is imposed by the narrow channels through which lymph passes out of the thorax into systemic veins. Accordingly, the pulmonary lymphatic system, which seems better suited to return proteins than water to the systemic circulation, may become a limiting factor in relieving pulmonary edema in states of unremitting water movement into the extravascular spaces.

The anatomic and physiologic principles are then applied to current clinical enigmas, such as "shock lung," high-altitude pulmonary edema, and the edema that follows an overdose of narcotic agents, such as heroin. In "shock lung" after severe systemic hypotension, nonuniform pulmonary hypoperfusion is identified as the critical pathogenetic factor in the pulmonary edema that occurs during recovery, i.e. after systemic blood pressures have been restored to normal by large transfusions. The corresponding etiologic role for high-altitude pulmonary edema is attributed to anatomic variations in precapillary resistances in the lungs during a burst of severe pulmonary hypertension. The situation is more complicated for the pulmonary edema that follows narcotic overdosage since not only may the medication elicit severe respiratory depression, arterial hypoxemia, respiratory acidosis, and their sequelae–left ventricular failure, leakage of minute pulmonary vessels, and impaired lymphatic drainage–but the self-administered medication may be contaminated with substances that may, per se, cause minute pulmonary vessels to leak.
Effect of Propranolol, Procainamide, and Lidocaine on Ventricular Automaticity and Reentry in Experimental Myocardial Infarction
Authors: GAMBLE OLIVE W. , COHN KEITH
Published: June 2012

The importance of two arrhythmogenic mechanisms, ventricular reentry and automaticity, was assessed after coronary ligation in 35 cats. Automaticity was estimated by the frequency of ventricular escape beats after intravenous acetylcholine, and reentry was estimated by the number of repetitive beats induced by premature ventricular stimuli. Increased automaticity only was present after coronary ligation in two studies; increased reentry only was noted in 24; and both increased automaticity and reentry were seen in nine studies. Incremental doses of lidocaine (2-4 mg/kg), propranolol (0.1-0.3 mg/kg), or procainamide (5-15 mg/kg) consistently returned automaticity to normal. Procainamide abolished repetitive beats in 12 of 13 studies, propranolol did so in eight of 11, but lidocaine did so in only six of 17. Repetitive beats actually increased in six studies after lidocaine, at a time when lidocaine blood levels were in the lower therapeutic range. A persistent arrhythmia appeared after coronary ligation in 12 studies; in 10 the disappearance or persistence of the arrhythmia after drug administration matched the disappearance or persistence of repetitive beats. We conclude that both reentry and increased ventricular automaticity appear during myocardial infarction but that reentry seems of greater importance in the genesis of arrhythmias. These drugs are more reliable in normalizing automaticity than in abolishing reentry; the failure of a drug may thus be related to its failure to abolish reentry. Moreover, lidocaine may accentuate ventricular reentry, especially at the lower blood levels.
Clinical and Anatomic Implications of Intraventricular Conduction Blocks in Acute Myocardial Infarction
Authors: SCHEINMAN M. , BRENMAN B.
Published: June 2012

The electrocardiogram in 480 patients with acute myocardial infarction showed right bundle-branch block (RBBB) with normal QRS axis in 18 patients (3.7%), left bundle-branch block (LBBB) in 31 (8%), RBBB and left anterior hemiblock (LAH) in 23 (4.8%), RBBB and left posterior hemiblock (LPH) in four (1%), LAH alone in 20 (4%), LPH in one (0.2%), and no evidence of intraventricular conduction (I-V) disturbance in 383 (80%). Eighteen of the 97 patients with I-V block showed 1° A-V block, and seven of the 18 (39%) showed abrupt progression to high-grade A-V block, while only six of 79 (8%) without 1° A-V block showed similar progression.

Cause of death in patients with I-V block was cardiac failure and/or shock in 92%; only three instances of primary asystole occurred. The incidence of complete heart block was higher in the I-V disease group (15%) than in the group without block (5%), but not significantly. Patients with LAH or RBBB and LAH usually had occlusion of the left anterior descending artery with extensive septal infarction, while patients with RBBB or LBBB had a more variable pattern of vessel involvement. Presence of I-V block in patients with acute myocardial infarction implies a hectic clinical course with poor prognosis, but does not justify prophylactic temporary transvenous intracardiac pacing except perhaps in the subgroup with associated 1° A-V block.
Pulmonary Atresia or Severe Stenosis and Coronary Artery-to-Pulmonary Artery Fistula
Authors: KRONGRAD EHUD , RITTER DONALD G. , HAWE ANTHONY , KINCAID OWINGS W. , MCGOON DWIGHT C.
Published: June 2012

Five patients have had the common features of pulmonary atresia or severe stenosis associated with a septal defect and a coronary artery-to-pulmonary artery (CA-PA) fistula. Four had pulmonary valvular atresia, and one had severe pulmonary stenosis. In all five, the CA-PA fistula contributed the principal component of the pulmonary blood flow. Cyanosis, continuous murmur, right ventricular hypertrophy, and decreased or normal pulmonary vascularity were frequent clinical manifestations, but angiocardiography was required to establish the diagnosis. The fistula was a side-to-side communication between the left coronary artery and the main pulmonary artery in each of the five patients. The dilated proximal coronary artery connecting the aortic root with the pulmonary artery gave a unique angiocardiographic appearance distinguishing it from truncus arteriosus or aorticopulmonary window. It is suggested that this unique angiocardiographic appearance be called an "aorticopulmonary tunnel." The surgical repair of this anomaly is closely related to that for severe tetralogy of Fallot and should involve a comparable risk and achieve a comparable result.
Serial Determination of Plasma Catecholamines in Myocardial Infarction
Authors: VIDEBAEK JØRGEN , CHRISTENSEN NIELS JUEL , STERNDORFF BENT
Published: June 2012

By the use of a precise and sensitive double-isotope derivative technic, plasma catecholamine concentration was measured at 2-hour intervals in 10 patients during the first 48 hours of myocardial infarction.

Plasma catecholamine concentration was elevated in most patients, but to an extremely variable degree. In each patient, however, the values were rather stable during the study period. High levels of plasma catecholamines were correlated to the clinical state of the patients. Patients who received antiarrhythmic treatment on admission to the hospital had higher values than untreated patients. There was no temporal correlation between plasma catecholamine concentration and ventricular arrhythmias. In contrast to the plasma catecholamine level, the heterotopic ventricular activity declined spontaneously in the untreated patients within the study period.

It is emphasized that the plasma catecholamine concentration in patients with acute myocardial infarction is considerably lower than the level necessary to produce arrhythmias in experimental myocardial infarction.
Comparison of Ultrasound and Cineangiographic Measurements of the Mean Rate of Circumferential Fiber Shortening in Man
Authors: COOPER RONALD H. , O'ROURKE ROBERT A. , KARLINER JOEL S. , PETERSON KIRK L. , LEOPOLD GEORGE R.
Published: June 2012

It has been shown that cineangiographic measurement of the mean rate of circumferential fiber shortening (mean V
CF
) at the minor left ventricular equator is a reliable method for evaluating the mechanics of cardiac performance. Since fiber shortening can be derived from the echocardiogram, we sought to validate the measurement of mean V
CF
by this noninvasive technic in patients studied by both methods. In 15 patients considered to have normal left ventricular function, the average mean V
CF
determined by ultrasound was 1.29 ± 0.23 circumferences/sec, while in the 13 patients with reduced left ventricular performance this value was 0.75 ± 0.16 circumferences/sec (
P
< 0.001). Values of mean V
CF
by the two technics were similar and separated normal from abnormal ventricular function in 27 of 28 patients. The average mean velocity of posterior wall motion was 4.7 ± 1.1 cm/sec in normal patients and 3.9 ± 1.3 cm/sec in abnormals, but posterior wall velocities did not correlate well with either ultrasound or cineangiographic determinations of mean V
CF
. Ejection fraction calculated from ultrasound measurements correlated significantly with the ejection fraction calculated by cineangiography (r = 0.83,
P
< 0.0001). The ejection fraction and mean V
CF
, as determined by ultrasound in the 28 patients, correlated well (r = 0.92,
P
< 0.0001), but there were six discordant points.

From these studies we conclude that the ultrasound determination of mean V
CF
is a valid method for distinguishing normal from abnormal myocardial performance of the left ventricle. These data also support the use of ultrasound in determining ejection fraction. Estimation of posterior wall velocity, although perhaps useful in the serial study of the same patient, seems limited in its ability to assess cardiac performance accurately.
Atresia of the Left Coronary Artery Ostium
Authors: MULLINS C. E. , EL-SAID G. , MCNAMARA D. G. , COOLEY D. A. , TREISTMAN B. , GARCIA E.
Published: June 2012

Symptoms and electrocardiographic changes of acute myocardial ischemia in a 10-year-old boy resulted from congenital atresia of the ostium of the left coronary artery. At 14 years of age persistence of symptoms and a positive exercise test prompted surgical treatment by aortocoronary artery saphenous vein bypass graft. Two months postoperatively, the symptoms and the abnormal findings on exercise test had subsided and forward flow through the graft to the left coronary artery was demonstrated by contrast angiography.
Hemodynamic and Anatomic Correlation of Electrocardiogram in Double-Outlet Right Ventricle
Authors: KRONGRAD EHUD , RITTER DONALD G. , WEIDMAN WILLIAM H. , DUSHANE JAMES W.
Published: June 2012

Scalar electrocardiograms of 31 patients with double-outlet right ventricle (19 with and 12 without pulmonary stenosis) were correlated with the hemodynamic and anatomic findings. Atrioventricular conduction defects, intraventricular conduction delay, and counterclockwise frontal-plane loops were found less often than formerly reported. Counterclockwise frontal-plane loops were found with, as well as without, pulmonary stenosis. The presence or absence of left ventricular hypertrophy did not correlate with the severity of pulmonary vascular obstructive disease. Electrocardiographic evidence of left atrial enlargement was difficult to interpret. Additional intracardiac malformations could not be appreciated from the electrocardiographic findings. The predictive value of the electrocardiogram for the diagnosis of double-outlet right ventricle was considered to be low. In patients with double-outlet right ventricle without pulmonary stenosis, the electrocardiogram was not helpful in predicting the severity of pulmonary vascular obstructive disease.
Pathology of Angina Pectoris
Authors: VLODAVER ZEEV , NEUFELD HENRY N. , EDWARDS JESSE E.
Published: June 2012

Among the wide variety of causes of angina pectoris, two major categories may be recognized: the anatomic, causing arterial obstruction, and the functional.

The anatomic causes may be divided according to anatomic sites as follows: (1) the major coronary arterial trunks and their epicardial branches, (2) the coronary ostia at the aorta, and (3) the intramyocardial "small" arteries. The major coronary arteries are by far the most common sites for anatomic lesions. Atherosclerosis in its various anatomic manifestations is responsible for about 90% of the cases of angina. Commonly, hypertension and, less commonly, valvular disease are associated. The balance of cases of angina result from various states given below. Nonatheromatous diseases of the major coronary arteries include embolism, primary dissecting aneurysm of a coronary artery, arteritis, and anomalous communication of a coronary artery. Coronary ostial narrowing results from various diseases of the aorta including atherosclerosis, saccular and dissecting aneurysm, inflammation, and calcification of the aorta in relation to origin of a coronary artery. Lesions causing obstruction of the intramyocardial arteries are commonly part of systemic diseases such as hematologic, embolic, metabolic, and degenerative.

Functional causes of angina pectoris include aortic valvular disease and functionally related conditions, thyroid disease, and pulmonary hypertension.
Coronary Angiography
Authors: BALTAXE HAROLD A. , LEVIN DAVID C.
Published: June 2012

The history, technic, and complications of coronary angiography have been discussed. Myocardial infarction caused by the procedure occurs in 0.3-0.9% of all cases. Two leading groups report an incidence of 1/1000 to 1/2500 deaths related to the procedure. Angiographic anatomy has been described. Indications for the procedure are: intractable angina in patients with or without a history of myocardial infarction and unexplained left ventricular failure or failure due to a left ventricular aneurysm. Among the debatable indications are: unexplained ECG changes, aortic valve disease, preinfarction patterns, cardiogenic shock, and follow-up angiograms after bypass surgery. If immediate surgery is not contemplated, left ventricular failure and a recent myocardial infarction are contraindication to the procedure. The limitations of the procedure are the radiographic resolution and the inconsistent anatomic pattern of minor vessels.
Left Ventricular Ejection Time in Valvular Aortic Stenosis
Authors: BACHE ROBERT J. , WANG YANG , GREENFIELD JOSEPH C.
Published: June 2012

Hemodynamic data obtained at cardiac catheterization from 40 patients with valvular aortic stenosis demonstrated that, although left ventricular ejection time was prolonged, the usual linear inverse relationship between heart rate and ejection time was preserved at a longer than normal mean ejection time. In contrast to this, the direct linear relationship between ejection time and stroke volume which exists in normal human subjects was totally obliterated in patients with aortic stenosis so that ejection time appeared to be totally unrelated to stroke volume. However, the degree of prolongation of left ventricular ejection time above that predicted from stroke volume (ΔLVET) was closely correlated with aortic valve area (AVA), so that aortic valve area could be predicted as AVA = 0.91 – 3.6 ΔLVET within 95% confidence limits of ± 0.16 cm
2
. Alternatively, if ejection time was not abnormally prolonged, it was possible to predict with 95% confidence that the aortic valve area was greater than 0.75 cm
2
in cross-sectional area and thus not within the range generally requiring surgical therapy.
Cardiac Manifestations of Marfan Syndrome in Infancy and Childhood
Authors: PHORNPHUTKUL CHARLIE , ROSENTHAL AMNON , NADAS ALEXANDER S.
Published: June 2012

The clinical profile and course of 36 infants and children with Marfan syndrome is reviewed. Cardiac abnormalities were present in 61% of the patients and were the major cause of death. Mitral regurgitation, the most frequently encountered cardiac lesion (47%), occurred in both males and females, while aortic regurgitation was present only in males. Arrhythmias were observed in four patients, and congenital heart disease (atrial septal defect) was observed in one. A distinguishing auscultatory feature was an apical mid or late systolic murmur preceded by single or multiple clicks. A characteristic electrocardiographic pattern of S-T segment and T-wave changes in leads II, III, aV
F
, and left precordial leads was noted in 11 patients. The prognosis of children with Marfan syndrome and isolated mitral regurgitation was usually good, whereas patients with combined mitral and aortic regurgitation had a rapidly deteriorating clinical course. The overall mortality in the group was 14%.
Echocardiography in the Diagnosis of Ebstein's Anomaly of the Tricuspid Valve
Authors: LUNDSTRÖM NILS-RUNE
Published: June 2012

Nineteen patients aged between 4 days and 40 years with Ebstein's anomaly of the tricuspid valve have been examined with echocardiography. The diagnosis was verified with angiocardiography in all but one patient. The results at echocardiography are compared with those found in some other patients where an echo from the anterior tricuspid leaflet could be obtained (atrial septal defect, total anomalous pulmonary venous return, pulmonary hypertension, and one patient with congenital tricuspid stenosis).

An echo from the anterior tricuspid leaflet could be obtained in all patients with Ebstein's anomaly. This echo had an abnormal pattern of movement with an abnormally anterior position during the entire diastole. A late tricuspid opening was found in most patients. A late tricuspid closure compared with the time of mitral closure was a constant finding. It is suggested that this late tricuspid closure is mainly caused by mechanical factors related to the abnormal, large anterior tricuspid leaflet. The abnormal pattern of movement of the echo from the anterior tricuspid leaflet with a late tricuspid closure has not been found in any other patient examined.
Mechanisms of Digitalis Toxicity
Authors: ROSEN MICHAEL R. , GELBAND HENRY , MERKER CHARLES , HOFFMAN BRIAN F.
Published: June 2012

Microelectrode technics were used to study effects of ouabain (O), 2x10
–7
moles/liter, on phase 4 of Purkinje fiber (PF) transmembrane potentials (TMP). Perfusion for 25-35 min with O caused an increase in phase 4 depolarization which resulted in either increased automaticity or occurrence of low-amplitude potentials (LAP). Increased automaticity was more frequent when PF had been stretched, when [K
+
]
o
= 2.5 mmoles/liter, and when O caused a marked decrease in resting membrane potential (RMP). LAP occurred at all [K
+
]
o
(2.5, 4.0, and 5.0 mmoles/liter), and were the typical response of unstretched fibers in which RMP had not decreased markedly. The magnitude of the LAP increased at [K
+
]
o
= 4.0 mmoles/liter and at faster stimulus rates. Threshold potential (TP) was decreased to a slightly greater extent than RMP. Although LAP did not result in spontaneous action potentials, superimposition of subthreshold depolarizations on LAP resulted in excitation. Whether O-induced increases in phase 4 slope result in automaticity or LAP depends on interrelationships between RMP, TP, and level of membrane potential reached during phase 4. Although hearts developing LAP due to digitalis toxicity may not demonstrate increased automaticity, the presence of phase 4 depolarization in the form of LAP may cause an impairment of conduction which is dependent on cycle length.
Conduction Intervals and Conduction Velocity in the Human Cardiac Conduction System
Authors: KUPERSMITH JOEL , KRONGRAD EHUD , WALDO ALBERT L.
Published: June 2012

Specialized fiber electrograms were recorded in 64 patients during open-heart surgery. Intervals were measured from the proximal His bundle, distal His bundle, and right and left bundle branches to the earliest QRS deflection in the limb lead ECG (pH-Q, dH-Q, RB-Q, and LB-Q interval, respectively). There was an increase of pH-Q intervals with increasing age such that at age 3 months the normal range of pH-Q interval was 13-27 msec, while at 14 years of age it was 32-54 msec. For patients 15 years of age and older, the normal range of pH-Q interval was 35-54 msec, similar to that reported by several investigators using catheter technic and suggesting that most His bundle electrograms recorded by catheter technic in fact record from the proximal His bundle. The dH-Q interval varied from 18 to 35 msec, the RB-Q interval from 18 to 30 msec, and the LB-Q interval from 20 to 39 msec. These normal ranges of RB-Q and LB-Q intervals are greater than previously reported. Overlaps existed between the normal range of pH-O and dH-Q or LB-Q intervals, dH-Q and RB-Q or LB-Q intervals and, at least in children, the pH-Q and RB-Q intervals. Thus the timing of a specialized fiber electrogram does not necessarily reflect its anatomic location. AV nodal electrograms were not recorded although the recording sites included the known anatomic location of the AV node. Conduction velocity in the His bundle was determined and averaged 1.5 m/sec (range 1.3-1.7 m/sec).
Intrarenal Blood Flow in Congestive Heart Failure
Authors: KILCOYNE MARGARET M. , SCHMIDT DONALD H. , CANNON PAUL J.
Published: June 2012

Intrarenal blood flow distribution was measured by the
133
xenon washout technic in 10 patients with heart disease who were studied at time of left and right heart catheterization. Renal washout curves were analyzed by computer using a weighted least-squares nonlinear regression technic. In three patients with heart disease without edema the compartment I blood flow rates (outer cortex) were not significantly different from those found in nine normal kidney donors. In seven patients with hemodynamic evidence of heart failure and clinical edema the compartment I flow rates were significantly lower than those of the normal control group and of a group of sodium-depleted hypertensive patients. The rate constants of isotope removal from more central regions of the kidney (compartments II and III) were not depressed to a similar degree. Infusion of furosemide into the renal artery induced diuresis in eight studies which was accompained by preferential increases in compartment I flow rates in six. The data suggest that preferential vasoconstriction of renal cortical vessels may contribute to increased sodium retention by the kidneys and to edema formation in patients with congestive heart failure.
Quantitative Radionuclide Angiocardiography
Authors: MALTZ DAVID L. , TREVES S.
Published: June 2012

A new method of determining pulmonary-to-systemic flow ratios (Qp/Qs) in patients with left-to-right shunts using radionuclide angiocardiography is described. It involves the analysis of pulmonary time-activity histograms using a gamma-variate model. It appears to be simple, relatively atraumatic, and superior to the methods using C
2
/C
1
ratios because, in addition to accurately detecting the presence of left-to-right shunts, it permits precise quantitation. In the 35 patients studied, it was found that Qp/Qs <1.2 could be separated from Qp/Qs > 1.2 and that when the Qp/Qs is between 1.2 and <3 the shunts could be accurately quantified.