bluuebunny/crossref_metadata_2025 huggingface dataset:
Results over a Ten-Year Period of Palliation followed by Corrective Surgery for Complete Transposition of the Great Arteries
Authors: CLARKSON PATRICIA M. , BARRATT-BOYES BRIAN G. , NEUTZE JOHN M. , LOWE JAMES B.
Published: June 2012

One hundred and twenty patients with transposition of the great arteries (TGA) were encountered over a decade. Survivors have been followed until after definitive repair, and 39% were alive when reviewed.

The majority (69%) had no significant communication between the pulmonary and systemic circulations. Of 48 patients in this poor-mixing group who had an atrial septectomy, 23 (48%) survived to have an atrial baffle repair at an average age of 37 months, and 37% were alive at the time of review. In contrast, 18 of 22 (82%) patients with poor mixing who had a balloon septostomy had a definitive operation at an average age of 13 months, and 17 (77%) survived.

Twenty patients (17%) had good mixing between the two circulations due to the presence of a large ventricular septal defect (VSD) or patent ductus arteriosus, and presented with mild cyanosis and heart failure. Of this group, 35% were alive when reviewed. Four of the five patients who had a successful atrial baffle repair and correction of associated lesions were less than 4 months of age when this was performed. Where TGA was associated with VSD and pulmonary stenosis, 36% survived.

Definitive operation at an early age has been made possible by the introduction of a surgical technic using profound surface-induced hypothermia and limited cardiopulmonary bypass.
Demonstration of Entrance Block into the Atrioventricular Node of Man
Authors: VARGHESE P. JACOB , DAMATO ANTHONY N. , PAULAY KAREN L. , GALLAGHER JOHN J. , LAU SUN H.
Published: June 2012

Entrance block of an atrial premature beat (APB) into the atrioventricular node is demonstrated by its lack of effect on the A-V nodal conduction of a subsequent beat which is introduced before the full recovery time of the A-V node. This phenomenon was demonstrated in five patients by using programmed atrial stimulation and His bundle recordings. Entrance block into the A-V node occurred in a narrow range (28-33%) of the basic cycle length and concealed conduction occurred at coupling intervals longer than this range. It appears that entrance block of these early APBs is due to a "functional block" between the atrium and the A-V node. The concept of an entrance block into the A-V node is useful in explaining some forms of the supernormal phase of A-V conduction as well as in the interpretation of complex arrhythmias.
Atrioventricular Conduction System in Left Bundle-Branch Block with Normal QRS Axis
Authors: CANNOM DAVID S. , GOLDREYER BRUCE N. , DAMATO ANTHONY N.
Published: June 2012

In nine patients with left bundle-branch block (LBBB), normal QRS axis, and normal P-R interval, atrial, His bundle, and ventricular electrograms were recorded. The extrastimulus method was utilized to determine the relative refractoriness of the various components of the atrioventricular conducting system.

The functional refractory period (FRP) of the A-V node was normal in all but one patient. In six patients, the effective refractory period (ERP) of the ventricular specialized conducting system (VSCS) was greater than the FRP of the A-V node. The differential refractoriness within the three components of the VSCS was determined. Before the ERP of the VSCS was reached, a leftward shift in the mean QRS axis was noted in all six patients, thus documenting participation of the left anterior division of the LBB in ventricular depolarization. We found no evidence that the left posterior division participated in ventricular activation and conclude that it is functionally silent in LBBB. Conduction abnormalities in the right bundle branch were demonstrated both by long H-V intervals and the fact that its ERP was prolonged.

The increased refractoriness of all three divisions of the VSCS suggests that the conduction abnormalities producing evidence of LBBB on the surface are trifascicular in nature.
Sail Sound in Ebstein's Anomaly of the Tricuspid Valve
Authors: FONTANA MARY E. , WOOLEY CHARLES F. , Goodwin Richard S. , Rieser George F.
Published: June 2012

Ebstein's anomaly represents an anatomic, pathologic, and physiologic spectrum. There have been few hemodynamic correlates for the observed auscultatory events. Multiple components of the first sound and "ejection" sounds are frequently described.

Cardiac catheterization, intracardiac sound-pressure studies (Telco), and cineangiograms were performed in three patients with Ebstein's anomaly who had a prominent early systolic sound.

The right ventricular pressure pulse was abnormal in all; an initial delta-wave configuration, followed by a more rapid pressure rise, produced a prolonged rise to peak pressure. The right ventricular pressure pulse is not that of a conduction defect alone; rather it suggests that the altered pattern of ventricular contraction and abnormal leaflet placement are contributing factors.

The early systolic sound was recorded in the atrialized right ventricle or right ventricle in all. It occurred just after the peak of the c wave in the atrialized right ventricle. In the right ventricle the sound occurred at the point where initial slow delta portion of right ventricular pressure pulse gave rise to rapid upstroke. The early systolic sound most likely occurs when the large, sail-like tricuspid valve reaches the limit of systolic excursion. The sound has been designated as the "sail sound," and may be the most specific auscultatory event in Ebstein's anomaly.
Clinical Spectrum of the Sick Sinus Syndrome
Authors: RUBENSTEIN JOEL J. , SCHULMAN CHARLES L. , YURCHAK PETER M. , DESANCTIS ROMAN W.
Published: June 2012

The clinical spectrum of the sick sinus syndrome (SSS) is described in a series of 56 patients who demonstrated either persistent unexplained sinus bradycardia (group I: eight patients); sinus arrest (group II: 15 patients); or bradycardia with episodic supraventricular tachyarrhythmias (group III: 33 patients). Coronary disease was the most common form of heart disease where etiology could be determined, but in 25 patients no clear etiologic diagnoses could be established. Thirty-three patients showed associated electrocardiographic conduction disturbances. Symptoms were common and were produced by both bradycardia and tachycardia. Eight patients in the bradycardia-tachycardia group experienced cerebral embolization. Despite bother-some symptoms, only six of the 56 patients died over an average follow-up of 7 years, and only one of these deaths appeared related to an arrhythmia. Drug therapy of bradycardia was generally ineffective, but digitalis was frequently helpful in patients with tachycardia. Electrical pacing was uniformly successful in treating symptoms of bradycardia but was disappointing in preventing tachyarrhythmias.
Echocardiography in the Diagnosis of Hypoplasia of the Left or Right Ventricles in the Neonate
Authors: MEYER RICHARD A. , KAPLAN SAMUEL
Published: June 2012

Echocardiographic studies were performed on six patients with autopsy-proved aortic atresia and hypoplastic left ventricle and two patients with surgically proved tricuspid atresia and hypoplastic right ventricle. The findings were compared to those from the echograms of 50 normal newborns who served as a control group. The ultrasound measurements obtained in the normal newborns were as follows: mean right ventricular end-diastolic dimension, 1.3 cm (range, 1.0 to 1.7), mean left ventricular end-diastolic dimension, 1.6 cm (range, 1.2 to 2.0), mean left atrial dimension, 0.9 cm (range, 0.6 to 1.3), and mean left ventricular outflow tract dimension, 1.0 cm (range, 0.7 to 1.2). The mean velocities of closure of the mitral and tricuspid valves during passive filling of the ventricles were 53 mm/sec and 43 mm/sec. The ranges were 36 to 80 mm/sec for the mitral valve and 34 to 56 mm/sec for the tricuspid valve.

In the patients with aortic atresia, the significant findings were a larger than normal right ventricular chamber (mean, 2.5 cm), a left ventricular chamber measuring less than 0.9 cm, and an absent or grossly distorted mitral valve echo. By contrast the patients with tricuspid atresia had very small right ventricular dimensions less than 0.6 cm, no demonstrable tricuspid valve echo, and a larger than normal left ventricle (mean, 2.3 cm). The above findings were diagnostic and were not confused with the normal newborn or other forms of congenital heart disease.
Effect of Pacing-Induced Tachycardia and Myocardial Ischemia on Ventricular Pressure-Velocity Relationships in Man
Authors: GRABER JOHN D. , CONTI C. RICHARD , LAPPE DONALD L. , ROSS RICHARD S.
Published: June 2012

Ventricular function was evaluated in 18 patients prior to left ventriculography and selective coronary arteriography. Simultaneous left ventricular pressure (catheter-tip manometer) and dP/dt were recorded at resting heart rates and during tachycardia induced by right atrial pacing. Pressure-velocity curves were constructed from which V
max
and maximum measured contractile element velocity (max V
CE
) were obtained. V
max
and max V
CE
initially increased with pacing-induced tachycardia in 17 of the 18 patients. Eight patients developed evidence of myocardial ischemia during atrial pacing. During the period of myocardial ischemia there was a decrease in V
max
and max V
CE
in all eight patients despite constant or increasing heart rate. In the 10 patients who did not develop evidence of myocardial ischemia with pacing-induced tachycardia, V
max
and max V
CE
continued to increase or remained constant with increasing rate. Peak left ventricular dP/dt increased coincident with the onset of myocardial ischemia in six of eight patients despite a fall in V
max
and max V
CE
in all eight patients during the ischemic period. A highly significant difference was demonstrated between V
max
values of patients with normal ejection fractions and patients with low ejection fractions, both at rest and during pacing-induced tachycardia.
Cardiac Surgery in Infants Less than Six Weeks of Age
Authors: EDMUNDS L. HENRY , FISHMAN NOEL H. , GREGORY GEORGE A. , HEYMANN MICHAEL A. , HOFFMAN JULIEN I.E. , ROBINSON SAUL J. , ROE BENSON B. , RUDOLPH ABRAHAM M. , STANGER PAUL
Published: June 2012

Sixty-one critically ill infants with congenital heart disease had operative treatment within 6 weeks of birth. Anatomic and physiologic diagnoses were established preoperatively by cardiac catheterization and angiography in all. A variety of palliative or corrective operations was performed to relieve specific hemodynamic burdens. Thirty-seven (61%) survived hospitalization, but 18 had one or more postoperative complications. At the present time, 29 (48%) are alive 9-45 months after operation. Although operative mortality and morbidity rates are high, none of these patients was expected to survive early infancy without operation.
Systemic Arterial Blood Pressure during Exercise in Patients with Atherosclerosis Obliterans of the Lower Limbs
Authors: LORENTSEN EINAR
Published: June 2012

Systemic intraarterial blood pressure and heart rate have been measured during exercise on a foot ergometer in 13 patients suffering from unilateral intermittent claudication. Each limb was exercised separately for 5 min. Both systolic and diastolic blood pressure increased to significantly higher levels during exercise with the diseased limbs than during exercise with the nondiseased limbs. No significant difference was found in heart rate. After cessation of exercise the blood pressure and heart rate dropped abruptly. For the first 2 min of recovery the systolic blood pressure in the diseased limbs stayed higher than the pressure measured at rest immediately before exercise. Ten patients were also exercised for 2 or 3 min with arrested circulation. During this period no significant differences between the diseased and nondiseased limbs were found in relation to blood pressure or heart rate.
Discrete Subaortic Stenosis
Authors: KELLY D. T. , WULFSBERC E. , ROWE RICHARD D.
Published: June 2012

Twenty-five patients with discrete subaortic stenosis were reviewed. Twenty were operated on for severe obstruction. Review of available data suggests there is a wide spectrum of the disease which may be divided into two main types designated I and II. Type I is a thin discrete membrane immediately under the aortic valve obstructing the outflow but not associated with narrowing of it. Type II is situated about 1 cm below the valve and consists of a fibrous ring, thicker than type I, and associated with muscular hypertrophy which narrows the outflow tract, encroaches on the anterior leaflet of the mitral valve, and may extend 1-2 cm downward. Both have a characteristic angiographic appearance. Results of surgery are good for type I but not satisfactory for type II. Aortic incompetence is likely to increase or develop following operation in both types.
Coronary Artery Occlusion in the Conscious Dog
Authors: REDWOOD DAVID R. , SMITH ELDON R. , EPSTEIN STEPHEN E.
Published: June 2012

Bradycardia, with or without hypotension, frequently occurs in the early phases of acute myocardial infarction. To determine the relative effects of alterations in heart rate and blood pressure on the degree of ischemic injury, the left anterior descending coronary artery was occluded for 15-min periods in closed-chest conscious dogs by inflating a balloon cuff previously implanted around the artery. The degree of myocardial ischemia was estimated by summating the S-T elevation recorded from 12 myocardial electrodes. Heart rate was increased by atropine or pacing and decreased by electrical stimulation of the vagus nerve. Hypotension was produced by venesection (average decrease in mean BP, 56 mm Hg). At normal arterial pressures there was a positive correlation between percent change in heart rate (range 30-215 beats/min) and percent change in S-T elevation (y = 0.75 X + 30.2, r = 0.93,
P
< 0.01). When myocardial ischemia was induced during hypotension and bradycardia, S-T elevation totaled 68 mv at 15 min of ischemia. When heart rate was increased to control levels in the presence of hypotension S-T elevation during myocardial ischemia was greater (mean difference 29 mv,
P
< 0.05). In contrast, when blood pressure was increased to control in the presence of bradycardia, S-T elevation in seven of 10 dogs was less than during hypotension and bradycardia. Thus, during experimental acute myocardial ischemia, hypotension induced by hemorrhage increases ischemic injury, and bradycardia reduces it. It is concluded that in acute myocardial ischemia increases in heart rate, even from slow baseline rates; may be deleterious to the myocardium. It remains to be determined whether alterations in the degree of myocardial ischemia induced by hemorrhagic-hypotension are analogous to those caused by the type of hypotension that often accompanies bradycardia occurring during acute myocardial infarction in man.
Total Anomalous Pulmonary Venous Drainage
Authors: SILOVE ERIC D. , BEHRENDT DOUGLAS M. , ABERDEEN EOIN , BONHAM-CARTER RICHARD E.
Published: June 2012

The spontaneous functional closure of the interatrial communication in total anomalous pulmonary venous drainage (TAPVD) subsequent to surgical correction of the TAPVD in infants is reported. Three cases are documented with descriptions of clinical features, cardiac catheterization data, thermodilution curves, and angiography. This evidence suggests that it might be unnecessary in infants to close the interatrial communication at the time of correction of the TAPVD. It also suggests that balloon atrial septostomy may sometimes be unwise before the first-stage correction.
The Conotruncus
Authors: GOOR DANIEL A. , DISCHE R. , LILLEHEI C. WALTON
Published: June 2012

The processes which are involved in the development of the normal outflow tracts of the ventricles are the following: The ostium bulbar torsion accounts for the concordant flow between the ventricles and the proximal conuses. The leftward shift of the ostium bulbi accounts for the partial overriding of the aorta over the left ventricle. The truncal rotation accounts for the twisted relationships of the great vessels and for the definitive interrelationships of the semilunar valves. The aortic conus absorption accounts for the aorticomitral fibrous continuity. These processes are not necessarily linked to each other. In the normal, mature heart the conus is represented by the subpulmonary portion of the right ventricular outflow tract.
Postoperative Evaluation of Myocardial Blood Flow in Aorta-to-Coronary Artery Vein Bypass Grafts Using the Xenon-Residue Detection Technic
Authors: LICHTLEN P. , MOCCETTI T. , HALTER J. , SCHÖNBECK M. , SENNING A.
Published: June 2012

By the use of the xenon-residue detection technic, myocardial blood flow (MBF) was assessed 3-17 months after surgery in nine patients with an aorta-to-left anterior descending bypass (LAD-BP), in nine patients with an aorta-to-right coronary artery bypass (RCA-BP), and in two patients with both LAD-and RCA-BP. In addition, MBF was registered in the corresponding main coronary artery. In each case coronary angiography revealed a patent vein graft. LAD-BP flow averaged 58 ml/min/100 g, this being slightly lower than the average flow value recorded after injection into the main left coronary artery of these patients (64 ml/min/100 g). LAD-BP flow did not differ from the value recorded in 20 normal subjects (63.9 ml/min/100 g). In contrast, average RCA-BP flow amounted to 47.1 ml/min/100 g and was significantly higher than the values recorded in the obstructed main RCA of these patients (22.1 ml/min/100 g) (
P
< 0.0025) or those observed in 20 patients with severe disease of the right coronary artery (34.9 ml/min/100 g) (
P
< 0.025); no difference was seen between RCA-BP flow and the average of 20 normal subjects (46.1 ml/min/100 g). In six patients a two-to threefold increase of BP flow was found during exercise (50-100 w). Total coronary vascular resistance showed a similar behavior to MBF, not differing in the bypass area from the values obtained in the normal control groups. It is concluded that the venous bypass procedure substantially increases perfusion at rest and during exercise and that a good correlation exists between MBF and postoperative angiography.
Clinical and Hemodynamic Results of Intraaortic Balloon Pumping and Surgery for Cardiogenic Shock
Authors: DUNKMAN W. BRUCE , LEINBACH ROBERT C. , BUCKLEY MORTIMER J. , MUNDTH ELDRED D. , KANTROWITZ ARTHUR R. , AUSTEN W. GERALD , SANDERS CHARLES A.
Published: June 2012

The AVCO balloon pump has been employed in treating 40 patients with cardiogenic shock from acute myocardial infarction (CS-MI). All patients were given a trial of medical therapy with hemodynamic monitoring. The time from the development of shock to institution of intraaortic balloon pumping (IABP) was less than 24 hours in all but nine patients. Prior to IABP the mean hemodynamic values were: cardiac index (CI) 1.7 liters/min/m
2
; mean arterial pressure (MAP) 66 mm Hg; pulmonary artery wedge pressure (PAW) 22 mm Hg. After 24-48 hours of IABP the CI and MAP had increased 0.8 liters/min/m
2
and 8 mm Hg, respectively, and the PAW had decreased 4.8 mm Hg. During IABP the shock syndrome was reversed in 31 patients. Four of 25 patients treated with IABP alone survived to be discharged, but two have died from subsequent infarctions. Because of the persistent high mortality, 15 patients judged unable to survive off IABP have undergone emergency surgical procedures with IABP continuing during preoperative angiography and postoperatively. Six were long-term survivors. It is concluded: (1) IABP is a safe, effective means of supporting the circulation in CS-MI; (2) IABP alone will improve survival in some patients; (3) IABP can provide circulatory support during angiography and the perioperative period in patients requiring revascularization for survival; and (4) some patients with CS-MI have myocardial necrosis too extensive to permit survival without permanent circulatory assistance or total cardiac replacement.
Canine Electrocardiographic and Cardiac Electrophysiologic Changes Induced by Procainamide
Authors: ROSEN MICHAEL R. , GELBAND HENRY , HOFFMAN BRIAN F.
Published: June 2012

Microelectrode technics were used to study the effects of procainamide (PA) on electrophysiologic properties of canine Purkinje fibers (PF) perfused in an extra-corporeal circuit with arterial blood of donor dogs. Donor electrocardiogram (ECG) and blood pressure (BP) and electrophysiologic properties of the isolated PF were simultaneously monitored. PA, 25 mg/kg, was administered as a single intravenous injection and plasma PA concentrations (PPAC) were determined spectrophotometrically. A decrease in PF automaticity was noted within 5-10 min of PA injection. Within 20 min, when PPAC was 10 µg/ml, amplitude and maximal rate of rise of phase 0 of the AP and conduction velocity (CV) decreased and alterations in AP duration and refractoriness were noted. BP and ECG rate were unchanged but the QRS complex had widened. At PPAC = 10-20 µg/ml (induced by further PA infusion) the aforementioned changes were accentuated. At PPAC > 20 µg/ml membrane responsiveness was significantly depressed. These experiments suggest that therapeutic PA levels rapidly decrease PF automaticity. Slowing of conduction commences later, simultaneously with changes in QRS duration. Within the same time span and range of plasma levels there are alterations in AP duration and refractoriness. Membrane responsiveness is not significantly depressed until PPAC is well into the clinically toxic range.
Hematoma of the Interatrial Septum with Heart Block Secondary to Dissecting Aneurysm of the Aorta
Authors: YACOUB MAGDI H. , SCHOTTENFELD MARK , KITTLE C. FREDERICK
Published: June 2012

Four patients with a hematoma of the interatrial septum secondary to acute dissecting aneurysm of the aorta are described. Hematoma of the interatrial septum presents with clinical features of acute dissecting aneurysm of the aorta and partial or complete heart block. Anatomically, the hematoma traverses the aortoatrial space to involve the A-V node and the bundle of His. Early operation is indicated.
Estimation of Infarct Size in Man and its Relation to Prognosis
Authors: SOBEL BURTON E. , BRESNAHAN GERALD F. , SHELL WILLIAM E. , YODER RICHARD D.
Published: June 2012

Infarct size was assessed quantitatively in 33 patients with acute myocardial infarction with a new technic based on analysis of serial serum creatine phosphokinase (CPK) changes to determine its relationship to prognosis. We have recently measured infarct size in the conscious dog with this method which takes into account CPK distribution space, fractional disappearance rate, proportion degraded in myocardium, and proportion released into the circulation, and we have validated the method by measurement of myocardial CPK depletion in the same animals. In the present study, CPK activity (determined spectrophotometrically) and isoenzyme profiles (assayed electrophoretically) were measured in patient serum samples obtained every 2 hours. Infarct size was estimated by mathematical analysis of serial CPK changes utilizing the method previously developed in the conscious dog model. CPK isoenzyme profiles demonstrated prominent anodal bands, absent from normal serum, indicating that enzyme elevations reflected CPK released from heart rather than skeletal muscle. In 19 class I-II survivors (New York Heart Association) estimated infarct size was 31 ± 4 CPK-gram-equivalents (CPK-g-Eq). It was significantly larger (
P
< 0.01), 103 ± 14, in nine patients who died and in four class III or IV survivors (91 ± 8). Estimation of cumulative infarct size differentiated patients with electrocardiographic changes and clinical sequelae from complications such as pericarditis from those patients with extension of infarction. Thus, infarct size can be assessed quantitatively in patients with acute myocardial infarction and provide a useful diagnostic and prognostic index based on the extent of myocardial damage.
Regional Left Ventricular Performance in the Year following Myocardial Infarction
Authors: FEILD BOLLING J. , RUSSELL RICHARD O. , DOWLING JOHN T. , RACKLEY CHARLES E.
Published: June 2012

The relationship of abnormal regional myocardial performance to left ventricular (LV) function 2-12 months following transmural myocardial infarction was investigated in 25 patients by quantitative biplane angiocardiography. Abnormally contracting segments (ACS) (akinetic or dyskinetic) of the LV were identified in 24 patients. Their sites correlated with the electrocardiographic locations of infarction. ACS were expressed as a percentage (ACS%) of the end-diastolic ventricular circumference, and the percentages obtained correlated with ejection fraction (EF) (r = —0.838, P = 0.0001) using a quadratic regression equation. The group of patients (N = 8) with heart failure (paroxysmal nocturnal dyspnea and/or ventricular gallop sound) demonstrated a significantly lower mean value for EF (
P
= 0.0003) and a significantly larger mean value for ACS% (
P
= 0.0041) than the group of patients (N = 16) without heart failure. EF sharply separated the two groups. ACS% was a poor separator because in the majority of patients in both groups it was between 14 and 38%. Since EF sharply separated the heart failure and non-heart failure groups but ACS% did not, a theoretic model was developed to assess the contribution of the remaining myocardium to LV function. The curve described by the model did not differ significantly from the curve derived from the quadratic regression equation. Data from heart failure and non-heart failure patients were generally separated by a point (EF = 0.30, ACS = 23%) on the theoretic curve. Abnormal function of the nonakinetic myocardium was considered to be present when observed EF was lower than predicted EF for the observed ACS%.

Thus, within the year following transmural myocardial infarction, the relative size of an abnormally contracting region of the ventricle was quantitatively related to impairment of LV function. The spherical model not only provided a framework for relating the clinical status of a patient to both ventricular function and size of the ACS, but also offered a means of estimating the function of the myocardium that appeared angiographically to be nonakinetic.
Intravascular Platelet Aggregation in the Heart Induced by Norepinephrine
Authors: HAFT JACOB I. , KRANZ PAUL D. , ALBERT FRANK J. , FANI KAZEM
Published: June 2012

Aggregated platelets and occlusive platelet thrombi were found in small myocardial vessels of dogs on electron-microscope examination after prolonged infusion of norepinephrine. The etiology of the myocardial necrosis and fibrosis induced by catecholamines in experimental animals and seen in patients with pheochromocytoma and patients after norepinephrine treatment for shock may be related to this intravascular platelet-aggregating effect of catecholamines. The link between stress and acute myocardial infarction may be via catecholamine-induced intravascular platelet thrombosis. If the thrombogenic theory of atherosclerosis is valid, platelet aggregation induced by catecholamines may be the mechanism whereby arteriosclerotic heart disease is related to stress.
Serum Lipids and Lipoproteins in Men after Myocardial Infarction compared with Representative Population Sample
Authors: GUSTAFSON ANDERS , ELMFELDT DAG , WILHELMSEN LARS , TIBBLIN GÖSTA
Published: June 2012

A nonselected series of 229 postmyocardial infarction (MI) patients was studied for up to 2 years following hospitalization. Their lipoprotein patterns, serum cholesterol, and triglyceride values were compared to those of a random population sample of men at comparable ages.

Hyperlipoproteinemia, cholesterol, and triglyceride elevations were more common in MI patients than in men in the random sample, occurring with greatest frequency in the younger patients. There was a trend toward higher mortality among patients with hyperlipoproteinemia. Types II A and B were very common in young patients.

Serum cholesterol values were significantly higher in the youngest patients and serum triglycerides higher than in the controls in age groups ≦ 40, 46-50, and 51-55 years.
H-V Intervals in Left Bundle-Branch Block
Authors: ROSEN KENNETH M. , EHSANI ALI , RAHIMTOOLA SHAHBUDIN H.
Published: June 2012

H-V interval in left bundle-branch block (LBBB) reflects conduction time in the His bundle and right bundle branch. H-V intervals were measured in 57 patients with LBBB, allowing definition of three groups of patients. Group A consisted of 14 patients with normal H-V (less than 50 msec), group B consisted of 21 patients with intermediate H-V (50-60 msec), and group C consisted of 22 patients with prolonged H-V (greater than 60 msec).

Arteriosclerotic heart disease (ASHD) was most frequent in group A (
P
< 0.02), while hypertension was most frequent in group C (
P
< 0.15). Mean P-R interval ±
sem
was 0.172 ± 0.013 sec in group A, 0.185 ± 0.007 sec in group B, and 0.225 ± 0.014 sec in group C (
P
< 0.05). Mean QRS duration was 0.138 ± 0.004 sec in group A, 0.144 ± 0.004 sec in group B, and 0.157 ± 0.003 sec in group C (
P
< 0.01). Mean frontal axis was –8° ± 12° in group A, –16° ± 12° in group B, and –28° ± 8° in group C (
ns
).

The frequent association of LBBB, normal H-V, and ASHD suggested the presence of isolated ischemic disease of the left bundle branch. In contrast, the frequent association of LBBB, prolonged H-V, and absence of ASHD was suggestive of sclerodegenerative bilateral bundle-branch disease. In a patient with LBBB, the occurrence of both first-degree A-V block and a QRS duration of 0.16 sec or greater strongly suggested the likelihood of H-V prolongation.
Evolution of Abnormalities in Left Ventricular Function after Acute Myocardial Infarction
Authors: BRODER MARTIN I. , COHN JAY N.
Published: June 2012

Twelve patients with acute myocardial infarction (AMI) were studied by left ventricular (LV) catheterization, echocardiography, and volume manipulation (tourniquets, phlebotomy, and dextran infusion) within 24 hours of infarction (study 1) and 3 weeks later (study 2). Three patients also were studied 6-10 months later (study 3). Cardiac index rose (from 2.50 to 3.15 liters/min/m
2
) and right atrial pressure fell (from 9.4 to 5.3 mm Hg) from study 1 to study 2. LV end-diastolic pressure (LVEDP) remained elevated (21.8 mm Hg at study 1 and 20.9 mm Hg at study 2) and was actually higher at study 2 in six patients who were otherwise improved. At study 1, end-diastolic ventricular diameter was within normal limits in five patients with clinical LV failure, four of whom had grossly elevated LVEDP. At study 2, ventricular diameter remained normal in three patients with elevated LVEDP but no LV failure. At study 3, LVEDP was still elevated in two patients and chamber diameter normal in two and slightly increased in one. Ventricular function curves (LVEDP vs stroke index) constructed from results during volume manipulation showed no consistent improvement during convalescence.

These data indicate that clinical improvement after AMI is not usually associated with a fall in LVEDP or a normalization of the impaired LV function curve. Normal ventricular diameter indicates normal ventricular volume which, in the presence of an elevated LVEDP, suggests a persistent decrease in LV compliance.
Changes in Left Ventricular Performance from Early after Acute Myocardial Infarction to the Convalescent Phase
Authors: RAHIMTOOLA SHAHBUDIN H. , DIGILIO MICHAEL M. , EHSANI ALI , LOEB HENRY S. , ROSEN KENNETH M. , GUNNAR ROLF M.
Published: June 2012

Left ventricular performance was assessed in 22 patients early (within the first 2 days) after acute myocardial infarction (AMI) and again during the convalescent phase (3-5 weeks later). Left ventricular end-diastolic pressure (LVEDP) fell from the early to the late study by an average of 10.7 mm Hg in the 12 (55%) group A patients. In these patients, cardiac index (CI) and left ventricular stroke work (LVSW) increased by an average of 0.65 liters/min/m
2
and 63.8 g-m, respectively, and the mean right atrial pressure fell by 2.4 mm Hg. These changes were statistically significant (
P
< 0.05). Left ventricular (LV) function was improved in this group of patients.

LVEDP increased in the other 10 patients and they were subdivided into groups B and C depending on whether CI increased or decreased. In six patients (27%), LVEDP increased by 5 mm Hg and CI increased by 0.4 liters/min/m
2
(group B); the
P
value for these changes was < 0.05. Group B patients also had an increase of mean arterial pressure and left ventricular ejection time, and thus the alterations in LVEDP and CI could have resulted from an increase of arterial pressure. In four patients (18%), LVEDP increased by 11.5 mm Hg, CI decreased by 0.9 liter/min/m
2
, and LVSW was reduced by 34.5 g-m (group C). Although the decreases of CI and LVSW were not statistically significant in group C patients, LV function had deteriorated. In the follow-up period, three of the four patients in group C died and the fourth patient is in functional class IV.

Therefore, in the convalescent period ventricular function had improved in 55%, and had deteriorated in 18% of cases. The changes in LV function could not have been predicted on the basis of the clinical features, systolic time intervals, or the initial hemodynamic findings. Patients whose ventricular function deteriorated during convalescence had a very poor prognosis.
Transposition of the Great Arteries
Authors: TYNAN MICHAEL
Published: June 2012

Sequential cardiac catheterizations were performed on 19 infants with complete transposition of the great arteries (TGA). None had any additional cardiac abnormalities other than an atrial septal defect. All were under 3 months of age at the time of the initial study. The pulmonary artery pressures and pulmonary-to-systemic vascular resistance ratios were significantly higher under the age of 9 weeks than over this age. The major fall in pulmonary vascular resistance appeared to occur in the first 4 weeks of life. A systolic pressure gradient from the left ventricle to the pulmonary artery of more than 5 mm Hg (median 13) was found at all the investigations performed in patients over the age of 2 weeks. This suggests that such a pressure gradient is usual in TGA, and not a sign of pulmonary stenosis. No systematic distribution of pulmonary-to-systemic flow ratios or age-related changes in these ratios was demonstrated, but pulmonary flow was rarely the same as systemic flow. In TGA the pulmonary vasculature undergoes a maturation process with the transition from intra- to extrauterine life. This process is similar in magnitude and time scale to that seen in the normal human infant.
Exercise Hemodynamics of Pulmonary Valvular Stenosis
Authors: MOLLER JAMES H. , RAO SATYANARAYANA , LUCAS RUSSELL V.
Published: June 2012

Sixty-four children with pulmonary stenosis were studied by cardiac catheterization both at rest and on exercise. Whereas milder degrees of stenosis were associated with normal right ventricular function, more severe stenosis was associated with fixed stroke index and elevated RVEDP, and suboptimal response of cardiac index. These changes result from altered right ventricular compliance. In several the compliance abnormality was related to myocardial hypertrophy, whereas in four patients it was most likely caused by myocardial fibrosis.
Shortening of Electromechanical Systole as a Manifestation of Excessive Adrenergic Stimulation in Acute Myocardial Infarction
Authors: LEWIS RICHARD P. , BOUDOULAS HARISIOS , FORESTER WILBUR F. , WEISSLER ARNOLD M.
Published: June 2012

The relationship between shortened electromechanical systole (QS
2
I) and 24-hour urinary catecholamine excretion (E+NE) was studied in 51 patients admitted to the coronary care unit with suspected acute myocardial infarction. Among these patients, 24 had a documented acute myocardial infarction while 27 had chest pain without evidence of recent myocardial infarction. Patients receiving cardioactive drugs or with impaired renal function were excluded. Initial elevation of catecholamine excretion was found in 22 of 24 subjects with myocardial infarction and 14 patients without documented myocardial infarction. A close linear correlation (r = -0.82,
P
< 0.001) was noted between shortening of the QS
2
I and catecholamine excretion among all patients irrespective of the presence of documented infarction. Patients with serious arrhythmias had significantly higher levels of catecholamine excretion. In 13 patients with a short QS
2
I, 2.5 mg of propranolol given intravenously produced a significant lengthening of the QS
2
I while no change in the QS
2
I occurred in normal controls. This test provided useful corroborative evidence that the short QS
2
I was related to excessive adrenergic stimulation. In view of the current availability of effective beta-adrenergic blocking agents, these results may improve the selection of patients for antiarrhythmic therapy with these drugs.
Failure of Intracoronary Nitroglycerin to Alleviate Pacing-Induced Angina
Authors: GANZ WILLIAM , MARCUS HAROLD S.
Published: June 2012

Relief of angina by nitroglycerine has been attributed to two possible mechanisms: (1) Increase in myocardial blood supply by direct action of the drug on the coronary arteries. (2) Reduction in myocardial oxygen demand by action of the drug on the systemic circulation. Sublingual application of nitroglycerin in previous studies did not allow the ruling out of the operation of either or both mechanisms. This study was, therefore, designed in such a way that the effect of the direct action of nitroglycerin on the coronary bed on angina could be studied in the absence of changes in the systemic circulation. In 25 patients undergoing cardiac catheterization and coronary arteriography as possible candidates for revascularization surgery, nitroglycerin, 0.075 mg in 1 ml of 5% dextrose, was injected into the left coronary artery through the angiographic catheter during angina pectoris induced by pacing. Coronary sinus blood flow by the continuous thermodilution method, femoral artery blood pressure, and lead V
5
were recorded continuously. In 20 patients the procedure was repeated with injection into the right coronary artery. In none of the 25 patients did the intracoronary injection of nitroglycerin alleviate the angina during the 1-min observation period, whether injected into the obstructed artery or into the artery supplying collaterals to the obstructed artery. The intracoronary injection was ineffective despite a significant increase in coronary sinus blood flow in 14, lasting 26 sec on the average. This suggests that the increase in blood flow did not occur in the ischemic areas where it was needed, but in other areas where the arterioles were not maximally dilated by ischemia. This explanation is further supported by the fact that in five patients with very severe restriction of the left coronary artery system the coronary sinus blood flow failed to increase in response to intracoronary nitroglycerin during angina, but increased significantly in response to nitroglycerin after discontinuation of pacing and disappearance of angina. In six patients, 0.2 mg nitroglycerin injected intravenously 1 min following the intracoronary injection relieved the angina unaffected by the preceding intracoronary injection. The relief was associated with a fall in arterial blood pressure and coronary sinus blood flow. The study indicates that the direct action of nitroglycerin on the coronary bed plays little, if any, role in the antianginal effect of the drug, which appears to be due entirely to the action of the drug on the systemic circulation.
Coexistent Idiopathic Hypertrophic Subaortic Stenosis and Coronary Arterial Disease
Authors: GULOTTA STEPHEN J. , HAMBY ROBERT I. , ARONSON ALFRED L. , EWING KENNETH
Published: June 2012

Coexistent idiopathic hypertrophic subaortic stenosis (IHSS) and coronary arterial disease (CAD) was found in 10 patients studied because of disabling angina. Only one had experienced consistent relief of angina with nitroglycerin. All had systolic murmurs which had been ascribed to valvular stenosis or papillary muscle dysfunction. Mean patient age was 57 years. Nine were males. All patients were shown to have the characteristic hemodynamic and angiographic findings of classical IHSS. Coronary cineangiography revealed severe CAD in each patient. Precatheterization diagnosis of combined IHSS and CAD was difficult to make unless a very well-documented history of prior myocardial infarction was available, and clinical evaluation revealed the typical auscultatory and pulse contour changes of IHSS. In six of the patients clinical evidence alone was not sufficient to diagnose combined disease with any certainty. There is a significant incidence of IHSS in the coronary disease-prone age group. The possible coexistence of the two diseases has not been appreciated previously. Patients with IHSS and angina should be evaluated for CAD as they may benefit if therapy is directed at both disorders. Patients with CAD, angina, and systolic murmurs should be evaluated for possible IHSS, especially if coronary artery surgery is contemplated, since such therapy may be inappropriate or incomplete.
Echocardiographic Study of the Abnormal Motion of the Posterior Left Ventricular Wall during Angina Pectoris
Authors: FOGELMAN ALAN M. , ABBASI ABDUL S. , PEARCE MORTON L. , KATTUS ALBERT A.
Published: June 2012

Echocardiographic waves from the posterior left ventricular endocardium were recorded in 30 normal subjects and in nine patients during 13 anginal episodes. At rest the normal maximal systolic endocardial velocity (SEVM) was 6.2 ± 1.4 cm/sec, the mean systolic endocardial velocity (SEV) was 4.1 ± 0.7 cm/sec, and the systolic endocardial excursion (SEE) was 1.4 ± 0.3 cm. The maximal diastolic endocardial velocity (DEVM) was 18 ± 3 cm/sec, and the mean early diastolic endocardial velocity (DEV) was 9.4 ± 1.7 cm/sec. Exercise in 20 normals caused a significant increase in SEVM, SEV, DEVM, and DEV, but not SEE. In no instance did any of these values fall below the resting levels. The angina patients differed significantly from the normals having at rest a slower DEVM (15 ± 4 cm/sec) (
P
< 0.025) and DEV (8.4 ± 0.8 cm/sec) (
P
< 0.025). During exercise, but before angina, there was a significant increase in SEVM and SEV but not SEE, DEVM, or DEV. In no instance did any of these values fall below the resting levels. During angina SEVM and SEV reacted variably and together with SEE were not significantly different from the resting values. In contrast, there was a remarkable slowing of DEVM (8.2 ± 3.2 cm/sec) (
P
< 0.001) and DEV (5.7 ± 2.2 cm/sec) (
P
< 0.001). Five minutes after the pain and S-T-segment depression disappeared, the endocardium moved as it did before exercise.
Transient Left Posterior Hemiblock
Authors: BOBBA PIERO , SALERNO JORGE A. , CASARI ANGELO
Published: June 2012

Four cases with transient electrocardiographic features which have been attributed to left posterior hemiblock (LPH) are reported. These features were induced by the exercise test in patients with severe coronary artery disease. In all of them the following exercise-induced changes were noted: (1) A shift of the main QRS forces inferiorly and to the right (between +90° and +120°). (2) A definite shift of the initial 0.02 QRS vectors superiorly and to the left, causing a small Q wave to appear in leads II, III, and aV
F
and/or to disappear from leads I and aV
L
. (3) A S
I
Q
III
pattern. (4) A leftward displacement of the precordial transition zone. (5) An increase of QRS duration in about 0.02 sec. Gradual disappearance of the exercise-induced axis shift was observed in all four cases and these findings were compatible with multiple degrees of "incomplete" LPH. The occurrence of transient LPH patterns was related to the development of acute, transient injury in the posteroinferior wall of the left ventricle in the presence of segmental or widespread coronary artery disease and chronic posteroinferior damage. Before the exercise test, two patients had electrocardiographic patterns suggesting old myocardial infarction and the other two had repolarization changes related to inferior myocardial ischemia according to the angiographic findings.
Transcutaneous Measurement of the Elastic Properties of the Human Femoral Artery
Authors: MOZERSKY DAVID J. , SUMNFR DAVID S. , HOKANSON D. EUGENE , STRANDNESS D. EUGENE
Published: June 2012

Measurements of human femoral arterial wall properties have been obtained transcutaneously in a group of males who were clinically free of arteriosclerosis obliterans. The patients were divided into three groups according to age: under 35, 35-60, and over 60 years. Diameter and changes in diameter were measured using an ultrasonic echo-tracking system. Arterial pulse pressure was determined by the auscultatory method. The results suggest that arteries become stiffer with age. The pressure-strain elastic modulus (Ep) varied from 2.6 ± 0.3
sem
x 10
6
dynes/cm
2
in the young group to 6.3 ± 1.0
sem
x 10
6
dynes/cm
2
in the old group. These values are similar to those reported by other investigators using invasive and in vitro technics. Although statistical comparisons indicate a significant difference between groups, there was considerable variation within the groups. Not infrequently, values for Ep obtained from individuals in the oldest group fell well within the range of the values obtained in the young group.
Maximal Treadmill Exercise Electrocardiography
Authors: MARTIN CARROLL M. , MCCONAHAY DAVID R.
Published: June 2012

Electrocardiograms were recorded during and at 2-min intervals following maximal treadmill exercise in 100 patients and were correlated with coronary arteriograms, left ventricular cineangiograms, and resting and exercise cardiac hemodynamics. The incidence and extent of exercise-induced "ischemic" S-T segment depression increased significantly (
P
< 0.01) with increasing extent of coronary artery disease (CAD). A criterion of abnormality of 1.0 mm or greater S-T depression most accurately predicted the presence of CAD with a specificity (true negative) of 89% and a sensitivity (true positive) of 62%. Criteria of ≧0.75 and ≧0.5 mm S-T depression offered improved sensitivities (68 and 84%, respectively) but markedly reduced specificities (78 and 57%, respectively).

A significant correlation (
P
< 0.005) was found between increasing extent of exercise-induced S-T segment depression and the pulmonary artery wedge pressure during exercise. There were no correlations between the presence or extent of exercise-induced S-T depression and the resting or exercise pulmonary artery pressure, cardiac index, stroke-volume index, or exercise factor, or the resting left ventricular dp/dt, left ventricular end-diastolic pressure, left ventricular ejection fraction, or presence of asynergy on the left ventricular cineangiogram.

The maximal treadmill exercise test provided a noninvasive method for predicting the presence and extent of significant CAD in the individual patient with chest pain. Although a normal treadmill exercise test provided little insight into the underlying resting and exercise hemodynamics, an abnormal treadmill test (≧1.0 mm S-T depression) was associated with an abnormal increase in left ventricular filling pressure with exercise in 90% of the patients.