bluuebunny/crossref_metadata_2025 huggingface dataset:
Sound-Pressure Correlates of the Aortic Ejection Sound
Authors: WHITTAKER ARTHUR V. , SHAVER JAMES A. , GRAY SAMUEL , LEONARD JAMES J.
Published: June 2012

The sound-pressure correlates of the aortic ejection sound (AES) were studied in six patients without aortic valve disease (group 1) and in nine patients with valvular aortic stenosis (group 2) during diagnostic left heart catheterization. Aortic root sound and pressure events were recorded by a catheter-tip micromanometer simultaneously with the external phonocardiogram, indirect carotid pulse, and electrocardiogram. The AES in group 1 patients was coincident with the onset of pressure rise in the aortic root. This relationship was not altered by drug administration, although variations in the amplitude of the AES occurred. It was concluded that the AES in patients without aortic valvular disease is an exaggerated ejection component of the normal first heart sound, and that it is a root phenomenon related to the forceful ejection of blood into the aorta. The AES in group 2 patients was delayed 24 to 40 msec after the onset of pressure rise in the aortic root, was coincident with the anacrotic notch, and introduced the aortic ejection murmur. Aortic root sound and pressure were recorded simultaneously with aortic valve motion during angiography in two patients utilizing a cine trace system. The AES occurred when the domed valve reached its maximal excursion, and the interval between the onset of aortic pressure rise and the AES was equal to the total time required for the piston-like ascent of the dome. It was concluded that the AES in valvular aortic stenosis is valvular in origin. The amplitude of the valvular AES correlated best with valve mobility on the angiogram, and no correlation existed between its presence and the severity of the valvular stenosis.
Abnormal Hemodynamic Function After Disc Mitral Valve Replacement
Authors: VOGEL JOHN H. K. , PATON BRUCE C. , OVERY HUGH R. , BLOUNT S. GILBERT
Published: June 2012

Although disc valves have been used extensively for mitral valve replacement, few long-term hemodynamic studies are available. Twenty-five patients received a Kay-Shiley valve, and hemodynamic studies were obtained in 17 patients at an average interval of 15 months after operation. Left ventricular cineangiograms revealed mitral insufficiency in 8 of 15 patients. In three patients a poorly contracting myocardium was associated with elevated left ventricular end-diastolic pressures, suggesting the possibility of acquired endocardial fibroelastosis. The embolic rate was 38%. Two valves became severely stenosed, and two had severe paravalvular leaks which required replacement. Although most patients were improved symptomatically and hemodynamic studies revealed improvement, all had abnormal valve function, particularly during exercise.
Hemolytic Anemia Following Prosthetic Valve Replacement
Authors: RODGERS BRADLEY M. , SABISTON DAVID C.
Published: June 2012

Ten patients with marked hemolytic anemia secondary to prosthetic cardiac valve replacement are presented. Although the etiology of this disorder is not understood, available evidence supports the concept of blood destruction secondary to turbulence around valves as the primary factor. These studies illustrate the technical difficulties associated with reoperation and the disappointing results which often follow. Emphasis is placed on the role of iron replacement and folic acid therapy in association with moderate reduction in exercise. This regimen has produced gratifying results in the management of these patients.
Factors in the Mortality and Morbidity Associated with Surgical Treatment of Cerebrovascular Insufficiency
Authors: RANSON J. H. C. , IMPARATO A. M. , CLAUSS R. H. , REED G. E. , HASS W. K.
Published: June 2012

The mortality and morbidity associated with 267 surgical procedures for cerebrovascular insufficiency carried out over a 5-year period are reviewed. Patients with marked intracranial arterial disease on angiogram, with completed strokes, over 70 years old or who required continuous nursing care are identified as the highest surgical risks.

The introduction of monitoring of the oxygen saturation of lateral sinus venous blood has reduced the incidence of intra-operative new neurological deficit during general anesthesia from 9.1 to 4.4%.

Episodes of hypotension occurred in 27% of patients but were associated with 48% of grave complications. The occurrence of hypotension is related to diabetes, preoperative hypertension, and to the extent of the operative procedure.

Evidence is presented that hypotension is due to abnormal circulatory reflexes and may best be prevented by careful maintenance of intravascular volume.
Further Evaluation of Aortic Valve Homografts Sterilized by Electron-Beam Energy
Authors: BOWMAN FREDERICK O. , MALM JAMES R. , HARRIS PAUL D. , KAISER GERARD A. , KOVALIK ANTHONY T.
Published: June 2012

Clinical results with the use of irradiated aortic valve homografts in 45 patients are reported. These valves have functioned satisfactorily up to 2 years.

Forty-four per cent of the surviving patients developed a murmur suggestive of a degree of aortic valvular insufficiency. One required re-operation, and all others remain in excellent compensation.

Emphasis is placed on the precise surgical technique of implantation and the proper selection of graft size, as well as the technique of preservation of the graft in obtaining a satisfactory hemodynamic result.
Surgical Intervention in Chronic Postinfarction Cardiac Failure
Authors: HARMAN MAUREEN A. , BAXLEY WILLIAM A. , JONES WILLIAM B. , DODGE HAROLD T. , EDWARDS STERLING
Published: June 2012

Seven patients with severe, chronic postmyocardial infarction cardiac failure underwent open intracardiac operation following catheterization and quantitative biplane angiocardiographic studies. Four patients with mitral incompetence had valve replacements; three had dilated mitral rings and did not survive the immediate postoperative period. In contrast, the single surviving patient had papillary muscle dysfunction evident at surgery and had less severe myocardial impairment as indicated preoperatively by a lower end-diastole volume and higher ejection fraction. Three patients demonstrated significant clinical and hemodynamic improvement after resection of a sccared akinetic area of left ventricular myocardium. Although two of the three patients died within the first year of operation, neither died in congestive failure. The results of this study indicate that certain patients with chronic postinfarction heart failure may benefit from surgery.
Alternate Patterns of Premature Ventricular Excitation During Induced Atrial Bigeminy
Authors: COHEN STAFFORD I. , LAU SUN H. , SCHERLAG BENJAMIN J. , DAMATO ANTHONY N.
Published: June 2012

Alternate patterns of premature ventricular excitation have been observed during induced atrial bigeminy in 18 subjects, including five normal volunteers. Each study was performed in the cardiac catheterization suite where a transvenous catheter electrode was positioned in the right atrium. Coupled or paired stimuli were delivered to the atrium by an isolated battery-powered source at an adjusted interval which resulted in alternate patterns of ventricular excitation from alternate premature beats ("alternating premature ventricular excitation").

In most instances "alternating premature ventricular excitation" occurred when parameters of preceding cycle length, premature coupling interval, and atrioventricular conduction time were constant.

In man also some observations were made of His bundle excitation during premature atrial stimulation, and in the intact dog heart some observations were made of alternating premature ventricular excitation during His bundle stimulation.

A tenable explanation for alternating premature ventricular excitation is advanced which rests on three postulates: (1) A long cycle length is followed by a long refractory period. (2) The refractory period of each branch of the specialized conduction system is dependent on its preceding cycle length or recovery period; and (3) the diastolic recovery period of a blocked segment of the specialized conduction system is shorter than the recovery period when blockade does not occur.
Sound Spectrographic Diagnosis of Aortic Ball Variance
Authors: HYLEN JOHN C. , KLOSTER FRANK E. , HERR RODNEY H. , STARR ALBERT , GRISWOLD HERBERT E.
Published: June 2012

Abnormalities in the silastic poppets of cardiac valve prostheses have been detected with increasing frequency. Ball variance can cause serious mechanical dysfunction of the prosthesis and can result in sudden death. Contour sound spectrograms were recorded on 12 patients with ball variance confirmed by operation and 25 controls. In ball variance the frequency of the aortic opening sound at the second right intercostal space was decreased, with the peak frequency recorded being below 1,300 cycles/sec in 11 of the 12 patients. The peak frequency was greater than 1,300 cycles/sec in 24 of the 25 control patients. The remaining patient had peak frequencies in both the normal and abnormal range. The diagnosis of aortic ball variance in patients with triple valve replacement remains difficult because of the nearly synchronous tricuspid closing and aortic opening sounds. The sound spectrographic findings have been the most reliable objective evidence of ball variance in patients with Starr-Edwards aortic prostheses of the Model 1000 series.
Scalar Amplitude Measurements of Data Recorded with Cube and Frank Leads from Normal Children
Authors: BORUN E. RAYMOND , SAPIN SAMUEL O. , GOLDBERG STANLEY J.
Published: June 2012

Amplitudes of scalar deflections were measured in records obtained with cube and Frank lead systems from 542 healthy children. Significant correlations were observed between corresponding deflections recorded with the two lead systems. There were significant correlations between amplitudes of some scalar deflections and age, chest diameter, height, and weight, but the scatter of individual values was too large to allow accurate prediction of measurements from regression equations. Means for scalar amplitude measurements showed several patterns of change from infancy through adult years. Normal limits for these measurements should, therefore, be stratified by age in children as well as in adults. Normal limits for scalar amplitudes and ratios between amplitude measurements were presented for four age groups of children. Correlation between age and body measurements was so high in these children that further stratification of normal limits on the basis of body measurements is not likely to provide additional useful information. There were differences in scalar measurements between males and females 10 to 16 years of age, but these were small.
Deviations of the RS-T Segment in Acute Subendocardial Injuries
Authors: PRUITT RAYMOND D , BURCHELL HOWARD B. , ESSEX HIRAM E.
Published: June 2012

On isolated perfused canine hearts, studies were made of the electrocardiographic changes which attend injury to the endocardium of the free wall of the left ventricle and of changes which develop following extension of the injury onto the left ventricular aspect of the septal endocardium. In an epicardial lead, the depression of RS-T segment produced by a subendocardial injury of the free wall of the left ventricle disappeared almost completely when that same type of injury was extended onto the septum.
Great Toe Calorimetry in Peripheral Vascular Diseases
Authors: MENDLOWITZ MILTON , ABEL HAROLD A.
Published: June 2012

Blood flow was measured in the great toe calorimetrically in various peripheral vascular diseases, after release of sympathetic nerve tone by indirect heating supplemented by tetraethylammonium chloride. There was a striking decrease in blood flow in thromboangiitis obliterans.
The Pattern of Vascular Reactivity in Experimental Hypertension of Varied Origin
Authors: PAGE IRVINE H. , MCCUBBIN JAMES
Published: June 2012

The response of the arterial pressure to a variety of drugs acting on different parts of the vascular tree has been employed to determine the contrasting mechanisms of chronic hypertension experimentally produced in dogs. The results suggest that the pattern of response depends on the state of the extrinsic regulatory mechanisms of the blood vessels rather than on intrinsic change in vascular musculature. Contrasting with chronic renal hypertension, greatly increased vasomotor function causes increased peripheral resistance in chronic neurogenic hypertension. The hypertension seems to us to be due more to this increase in resistance than to increased cardiac output. The pattern of vascular responsiveness in acute hypertension is different from the chronic and emphasizes the importance of distinguishing between the two phases of hypertension.
Acute Rejection Following Cardiac Transplantation
Authors: SCHROEDER JOHN S. , POPP RICHARD L. , STINSON EDWARD B. , DONG EUGENE , SHUMWAY NORMAN E. , HARRISON DONALD C.
Published: June 2012

Nine patients have undergone cardiac transplantation at Stanford University Hospital. Three of these showed no clinical evidence of rejection and had essentially normal physical and phonocardiographic findings. There were eight distinct early rejection episodes in the other six patients. Early rejection was accompanied by decreasing QRS voltage, an early diastolic gallop, and frequently a rightward shift of the mean electrical axis of the heart. If not treated, this progressed to severe heart failure with a right ventricular heave, biventricular gallop, marked elevation of venous pressure with rapid
y
descent and severe dyspnea without orthopnea. Ultrasound measurements show increasing posterior wall thickness and overall heart diameter during the rejection episode. With aggressive therapy, all of these signs usually resolve rapidly, suggesting that dysfunction of the rejecting heart is secondary to the interstitial edema, vascular engorgement, and cellular infiltration, causing restriction of diastolic filling. These cardiovascular signs appear to aid detection of early cardiac rejection and allow treatment at an earlier stage of the rejection process.
Tricuspid Atresia with Increased Pulmonary Blood Flow
Authors: MARCANO BERTRAND A. , RIEMENSCHNEIDER THOMAS A. , RUTTENBERG HERBERT D. , GOLDBERG STANLEY J. , GYEPES MICHAEL
Published: June 2012

The pathologic and clinical findings in 13 cases of tricuspid atresia and increased pulmonary blood flow encountered in UCLA Medical Center were reviewed. In seven, the great vessels were normally related (group I), and in six, the great vessels were transposed (group II). In all group II cases, aortic arch anomalies were encountered, a finding not duly emphasized in previous reports. Comparison of the two groups revealed significant clinical and laboratory differences. Group II patients typically presented with severe congestive heart failure and expired within the first 2 months of life. Group I patients usually presented with mild congestive heart failure which responded to therapy. Five of the latter demonstrated progressive change from increased to decreased pulmonary blood flow during their clinical course and eventually required palliative shunt procedures, four prior to the age of 2 years and one at 5 years of age.

While the electrocardiogram demonstrated right atrial enlargement and left ventricular hypertrophy in both groups, the mean frontal plane axis was between –15° and –100° in group I and –75° and +75° in group II. QRS vector loops tended to be superiorly oriented in group I and inferiorly oriented in group II.

Because the natural history and prognosis in these two groups differ significantly, diagnostic efforts should include determination of the relationship of the great vessels. When transposition of the great vessels is demonstrated, aortography should be performed because of the high incidence of aortic arch anomalies.
Hemodynamic Responses to Oxygen Breathing in Children with Severe Anemia
Authors: CROPP GERD J. A.
Published: June 2012

Hemodynamic responses to 100% oxygen inhalation were examined in seven anemic children (hemoglobin 1.9 to 3.8 g/100 ml blood; hematocrit 9 to 14%). During air breathing mean values for cardiac index were 7.71 L/min/m
2
, for heart rate 129/min, for stroke index 61.7 ml/m
2
, and for systemic vascular resistance 11.5 R.U. Oxygen administration significantly decreased mean values of cardiac index to 6.61 L/min/m
2
, of heart rate to 119/min and of stroke index to 56.6 ml/m
2
, and increased mean systemic vascular resistance to 14.2 R.U. Oxygen breathing raised systemic oxygen content 23% and oxygen transport 5%, despite decreases in cardiac ouput. Since oxygen breathing did not change the hematocrit (and thus viscosity), the increase in vascular resistance indicates active vasoconstriction. It is postulated that in anemia tissue hypoxia causes vasodilation of systemic resistance vessels. When anemia is not severe, baroreceptor reflexes prevent significant reductions in blood pressure and systemic vascular resistance by compensatory, neurogenic vasoconstriction. When anemia becomes severe and vasodilation extreme, blood pressure is maintained by an increase in cardiac output. Cardiac output is elevated by decreased vagal inhibition and increased myocardial contractility, which cause tachycardia and increased stroke volumes respectively.
Studies in Human Atrial Flutter with the Use of Proximity Electrodes
Authors: KISHON YEHEZKIEL , SMITH RALPH E.
Published: June 2012

Ten patients with the electrocardiographic diagnosis of atrial flutter were investigated by exploration with electrodes within the esophagus and the right atrium. The records obtained were studied in regard to the timing of the intrinsic deflection and the contour of the atrial waves, as recorded at various sites.

In four patients, atrial activation progressed in sequence cephalad in the left atrial wall and caudad in the right atrium. This process continued through two thirds of the total atrial cycle, favoring "circus movement" as the underlying mechanism. In six other patients, activation was believed to originate low in the left atrium, with simultaneous spread of excitation of both atrial walls in a general cephalad direction and terminating within the first half (usually the first third) of the atrial cycle. This pattern is compatible with, but not conclusive of, an ectopic focal mechanism. Serial records in one patient are presented in which transformation of one type into a second type of atrial flutter is suggested. It is likely that at least two mechanisms are present in human atrial flutter.
Left Posterior Fascicular Block in Canine and Primate Hearts
Authors: WATT THOMAS B. , PRUITT RAYMOND D.
Published: June 2012

To determine the electrocardiographic consequences of experimentally produced left posterior fascicular block, electrocardiograms of three baboons and three dogs were recorded from extremity and chest leads, from an esophageal lead, and from atraumatic exploring epicardial leads both before and after left posterior fascicular block and again after right bundle-branch block. The following electrocardiographic changes were noted: In direct epicardial leads from sites overlying zones of delayed myocardial excitation (1) increased ratio of R to S; (2) later intrinsic deflection time; and (3) appearance or augmentation of the Q wave. These altered potentials also appeared as rotations of the mean spatial QRS electrical axis. The QRS duration increased slightly. The addition of RBBB produced a further delay in deflection time in epicardial leads from the RV and a further increase in QRS interval. The epicardial envelopment by the excitation process is portrayed in diagrams. These observations emphasize the need for caution in the diagnosis of left posterior fascicular block alone or in combination with RBBB.
Effects of Drugs and of Counterpulsation on Myocardial Oxygen Consumption
Authors: BRAUNWALD EUGENE , COVELL JAMES W. , MAROKO PETER R. , ROSS JOHN
Published: June 2012

A series of investigations on the determinants of myocardial oxygen consumption were reviewed and their relevance to the survival and function of ischemic tissue in the presence of coronary occlusion pointed out. Tension development, contractile state of the myocardium, and heart rate are the most important factors influencing cardiac oxygen consumption, and drugs commonly used in the treatment of patients with acute myocardial infarction appear to influence oxygen consumption by acting upon these three determinants. Thus, digitalis glycosides and sympathomimetic agents tend to increase myocardial oxygen requirements, since they improve the heart's inotropic state. However, this influence may be offset in the enlarged heart in which end-diastolic volume and tension are reduced. Agents which depress the heart exert the opposite effect. Electrocardiographic changes reflecting myocardial ischemia are intensified when isoproterenol is administered following coronary ligation.

Synchronized arterial counterpulsation reduces myocardial tension development and therefore oxygen consumption. An augmentation of myocardial oxygen needs in the presence of coronary occlusion may be expected to increase the size of the necrotic zone and to impair the function of the ischemic zone, while a reduction of oxygen consumption may be expected to exert the opposite effect.
Therapy of Angina Pectoris with Propranolol and Long-Acting Nitrates
Authors: GOLDBARG ALBERTO N. , MORAN JOHN F. , BUTTERFIELD THOMAS K. , NEMICKAS RIMGAUDAS , BERMUDEZ GUSTAVO A.
Published: June 2012

A double-blind study of the effects of isosorbide dinitrate, 10 mg given orally four times a day, propranolol, 40 mg four times a day, and the combination of these two drugs was performed on 21 patients with angina pectoris. Each patient received placebo, isosorbide, propranolol, and the combination of the two drugs for 1 month each in a random sequence over 4 months. The number of anginal pains and nitroglycerin tablets used were recorded, and a multistage treadmill ECG exercise test was performed after each treatment period.

Frequency of anginal pains was reduced significantly with propranolol (7.0±2.5 pains/week) and the combination of propranolol and isosorbide dinitrate (9.9±2.9) as compared with placebo (21.0±6.4). Similarly, the number of nitroglycerin tablets was reduced with propranolol-containing regimens. Isosorbide was not significantly better than the placebo. Symptomatic improvement with propranolol could be related to a reduction in heart rate, and the product of heart rate and systolic blood pressure during exercise (
P
<0.001). The capacity of these patients to perform a multistage exercise test, however, was not improved significantly, and the ischemic ST-segment changes were not altered by the treatments. Thus, propranolol appeared to be effective on the symptoms of angina pectoris, but it did not significantly improve exercise performance, and it did not prevent the ischemic patterns in the exercise ECG in this group of patients. Isosorbide dinitrate, alone or in combination with propranolol, was ineffective in this study.
Cerebral Symptoms in Pulmonary Arteriovenous Fistula
Authors: SISEL RONALD J. , PARKER BRENT M. , BAHL OM P.
Published: June 2012

Two cases of pulmonary arteriovenous fistulas with hemiparesis and other neurologic findings, possibly from paradoxical embolization, are described. Many theories have been put forward to explain the pathophysiology of the frequently present neurologic manifestations. We regard paradoxical embolization through the fistula as the most important factor in the pathogenesis of the neurologic deficit.

Due to the potential hazard of paradoxical cerebral embolization and possible subsequent brain abscess formation, surgical resection of all pulmonary arteriovenous fistulas wherever feasible is recommended.
Predisposing Factors in Sudden Cardiac Death in Tecumseh, Michigan
Authors: CHIANG BENJAMIN N. , PERLMAN LAWRENCE V. , FULTON MARY , OSTRANDER LEON D. , EPSTEIN FREDERICK H.
Published: June 2012

In an epidemiologic study of the total population of Tecumseh, Michigan, 98 deaths from coronary heart disease were observed between 1959 and 1965. Forty-five of the fatalities occurred within 1 hour of the onset of symptoms and were classified as sudden. The proportion of sudden deaths among men was nearly twice that among women, and the incidence increased progressively with age in both sexes.

Hypertensive heart disease, coronary heart disease, or diabetes mellitus had been detected on prior examination in 62% of those who died suddenly. Physiologic abnormalities associated with a high risk of coronary heart disease were also found more frequently than in the total Tecumseh population.

All but seven of the persons who died suddenly had abnormalities including arrhythmias and conduction defects which were detected in the standard 12-lead electrocardiogram.

Although sudden deaths often seem to occur without warning, the victims are predisposed by conditions which are detectable long before the catastrophic event. The identification of conditions which are precursors of sudden death from coronary heart disease permits a rational consideration of possible preventive measures.
Comparison of Oxygen Saturation of Blood in Azygos Vein and Superior Vena Cava
Authors: JAIN KEWAL K. , WAGNER HENRY R. , LAMBERT EDWARD C.
Published: June 2012

Blood samples from the superior vena cava (SVC) are usually considered an acceptable representation of mixed systemic venous return in identifying and quantifying left-to-right atrial shunts. However, if during sampling from the SVC unrecognized entrance of the catheter into the azygos vein takes place, diagnostic errors may result. Blood samples from the azygos vein were collected from 60 children with congenital heart disease and the oxygen saturations ranged from 20% to 92%. These saturations were compared to those of samples taken from the superior vena cava above the entrance of the azygos vein. No substantial difference (saturation within ±4%) was found in 24 patients, while 28 patients had a significantly higher saturation in the azygos vein (from +5% to +21%) and eight patients had a lower saturation (from –5% to –16%). A significant left-to-right shunt may be overlooked or erroneously thought to be present when sampling of blood takes place unknowingly from the azygos vein. Examples are presented.

Approaching from the groin it was possible to catheterize the azygos vein in two thirds of the cases when a deliberate attempt was made to do so.
Clinical Application of Serum Digitoxin Levels
Authors: BENTLEY J. D. , BURNETT G. H. , CONKLIN R. L. , WASSERBURGER R. H.
Published: June 2012

A simple, rapid, and reliable determination of plasma digitoxin levels is now available for clinical use. It can be determined in any clinical laboratory capable of determining a serum phosphorus if ATPase enzyme is available. Maintenance plasma levels range between 10 and 40 mµg/ml with a mean value of 25 mµg/ml. There is overlapping of maintenance and toxic serum levels in the higher ranges. Values over 45 mµg/ml warrant careful evaluation for digitalis intoxication.

Maintenance plasma levels can be achieved with or without the usual digitalizing dosage if time is not a factor. The daily regression rate is variable in cases of digitalis intoxication following drug withdrawal.

ECG changes (the degree of ST-segment depression, PR-interval prolongation, and multifocal premature contractions) were not good criteria for digitalis intoxication, although PR intervals above 0.24 sec consistently correlated with high plasma digitoxin levels. Variable second and third degree A-V block associated with mental confusion was a frequent presenting feature of digitalis toxicity.
Myocardial Force-Velocity Relationships in Clinical Heart Disease
Authors: HUGENHOLTZ PAUL G. , ELLISON R. CURTIS , URSCHEL CHARLES W. , MIRSKY ISRAEL , SONNENBLICK EDMUND H.
Published: June 2012

Myocardial force-velocity relationships were studied in 33 children and young people with varying heart lesions. From analysis of left ventricular pressures and consideration of left ventricular geometry, measured from biplane angiocardiograms, maximal contractile element velocity (V
max
) was determined by extrapolation of a stress-velocity plot to zero stress. The value of V
max
in each patient was compared with the assessment of cardiac function by usual hemodynamic criteria (left ventricular end-diastolic pressure [LVEDP], volume [LVEDV], and ejection fraction [EF]).

In general, patients with normal LVEDP, LVEDV, and EF had values for V
max
above 3 circumferences/sec. Patients with elevated LVEDP or LVEDV or with EF below 0.5 had lower values for V
max
. Three patients whose usual catheterization data suggested normal ventricular function were found to have low V
max
. In all three, other evidence for myocardial abnormality was found. Several patients with excessive afterloads had impaired function by conventional criteria, yet had normal V
max
.

Evaluation of myocardial mechanics in man with measurement of V
max
appears to aid significantly in evaluating patients with heart disease by giving an index to the state of the myocardium not available from routine catheterization data.
Systolic Hypertension in the Elderly
Authors: COLANDREA MICHAEL A. , FRIEDMAN GARY D. , NICHAMAN MILTON Z. , LYND CELIA N.
Published: June 2012

Isolated systolic hypertension (systolic blood pressure of 160 mm Hg or greater, diastolic blood pressure less than 90) was investigated in the Leisure World population at Seal Beach, California. The prevalence of this condition was 13.9% if the blood pressure at the initial examination was used but dropped to 2.7% if the subsequent two determinations of blood pressure were also reviewed.

Seventy-two of the subjects with persistent systolic hypertension were compared with 72 matched normotensive control subjects. Cardiovascular morbidity and mortality were generally more frequent among subjects with systolic hypertension. That this association is causal has yet to be proven.

In this elderly population isolated systolic hypertension was a labile, relatively infrequent condition associated with an increased risk of developing cardiovascular complications.
Function of Potential Bypass Tracts for Atrioventricular Conduction
Authors: SANO TOYOMI , SUZUKI FUMIO , TSUCHIHASHI HIROMICHI
Published: June 2012

Function of potential bypass tracts for the atrioventricular conduction was examined in isolated rabbit hearts using microelectrodes, a suction electrode, and bipolar electrocardiographic leads. After the normal A-V conduction was blocked by acetylcholine, conduction to the ventricle occurred with a much shorter A-V conduction time and without significant QRS change, when a point at the root of the inferior vena cava was stimulated. By analyzing the site of delay, this route was presumed to go from the right atrium to the lower portion of the His bundle bypassing the A-V node. When a point inferior to this point was stimulated, marked shortening of conduction time and marked QRS change occurred. This second tract seemed to exist between the right atrium and ventricle bypassing the specialized system. The third tract was found when an anterior point on the right atrium was stimulated. The conduction was markedly prolonged without changing the QRS. This route seemed to enter some point of the A-V node, inducing a detour within the node.
Malfunction of the Mitral Valve Prosthesis (Cutter-Smeloff)
Authors: LEE SIMON J. K. , ZARAGOZA A. J. , CALLAGHAN J. C. , COUVES C. M. , STERNS L. P.
Published: June 2012

Three cases of intermittent obstruction of the mitral prosthesis (Cutter-Smeloff) due to ball variance have been reported. The typical findings were marked variation in the arterial pulse and the intensity of the mitral closing sound and intermittent absence of the opening click. The phonocardiography revealed varying intervals from aortic closing sound to the opening click (A
2
- OC interval). Hemodynamic studies revealed fluctuating aortic and pulmonary artery wedge pressures in spite of normal sinus rhythm, due to impaction of the ball into the prosthetic ring, opening only with severe elevation of the left atrial pressure. At operation, the balls showed yellowish discoloration, but no disruption of sutures nor thrombosis of the prosthesis was found. The incidence of this phenomenon was 9% with the Cutter-Smeloff mitral prosthesis, but no such case was seen among patients with the Starr-Edwards mitral prosthesis.
Cardiac Transplantation in Man
Authors: BIEBER CHARLES P. , STINSON EDWARD B. , SHUMWAY NORMAN E. , PAYNE ROSE , KOSEK JON
Published: June 2012

To date, 12 of 18 patients receiving cardiac allografts at the Stanford Medical Center have died. Five of these died with some degree of graft failure resulting from rejection injury. The remaining seven demonstrated some morphologic evidence of rejection, but death was due to other causes including pulmonary hypertension in two, hemorrhage and sepsis in one, infection in two, cerebral embolism in one, and hepatic failure in one. Acute rejection injury was defined in 10 allografts, accelerated acute rejection in one, and chronic rejection in nine.

The clinical signs of allograft rejection and their morphologic correlates were essentially as predicted from the study of orthotopic canine cardiac allografts. The clinical features and most of the anatomic lesions of acute rejection were usually reversible by current methods of immunosuppressive therapy. Chronic rejection, manifested primarily by obliterative intimal proliferation in coronary arteries, was present in most allografts obtained from patients surviving at least 1 month. Its severity was apparently not related to the quality of the host-donor leukocyte antigen match, and it was not routinely detectable clinically. This intimal thickening may limit long survival of patients undergoing cardiac transplantation.
The Varying Clinical Spectrum of the Systolic Click-Late Systolic Murmur Syndrome
Authors: FONTANA MARY E. , PENCE HOBERT L. , LEIGHTON RICHARD F. , WOOLEY CHARLES F.
Published: June 2012

Striking auscultatory variations with changes in posture were observed in 30 individuals with either mid-late systolic clicks, late systolic murmurs, or both, particularly in the upright position. Twenty-seven patients had late systolic murmurs; in nine, however, the murmur was not heard until assumption of the sitting position. Mid-late systolic clicks were heard in 20 patients while supine and in three only on sitting. Click movement (usually toward the first sound) was common during sitting or standing. Late systolic murmurs became holosystolic in 25 patients. In 20, the murmur did not become holosystolic until standing. Systolic whoops, not heard in the supine position, developed on assumption of the sitting position (three patients) or standing (three patients). With prompt squatting, the auscultatory findings reverted to those heard in the supine position in eight of nine patients. All observations were confirmed with phonocardiograms. Structural alterations in the mitral valve complex resulting in systolic prolapse of leaflets into the left atrium occur in these patients. Posture related changes in mitral valve function most likely explain the auscultatory phenomena.
Intravenous Caval Interruption for Pulmonary Embolism in Cardiac Disease
Authors: MOBIN-UDDIN KAZI , BOLOOKI HOOSHANG , JUDE JAMES R.
Published: June 2012

Surgical ligation or plication of the inferior vena cava in acutely ill patients with significant cardiopulmonary disease carries a high mortality. Intravenous interruption of the inferior vena cava by an intracaval umbrella-like device placed under local anesthesia has been performed in 15 patients with significant cardiac disease: 12 with chronic congestive heart failure and 3 with intractable heart failure and shock. There was one early death from heart failure and shock three days after caval interruption and three late deaths from congestive heart failure and one from ruptured sigmoid diverticulitis. The remaining ten patients are alive and well 2 months to 11½ months after caval interruption. There has been no further recurrence of pulmonary embolism.
Eradication of Rheumatic Fever
Authors: MARKOWITZ MILTON
Published: June 2012

Rheumatic heart disease is considered one of the few forms of chronic heart disease which can be effectively prevented today. Yet the incidence of rheumatic fever is still appreciable and the complacency of many physicians and public health officials in regard to the rheumatic fever problem is unwarranted. It is timely, therefore, to reexamine the question of whether this disease can indeed be eradicated by presently available methods.

One of the major factors limiting the prevention of initial attacks with antibiotics is that about two thirds of the patients who develop rheumaic fever do so following either asymptomatic or mild streptococcal infections. Furthermore, the low socioeconomic group, in whom the risk of rheumatic fever is the greatest, is the least likely to receive adequate care even for overt respiratory infections. Although the number of recurrent attacks has been reduced, approximately 10% of rheumatic patients still develop recurrences either because they are not on prophylaxis at all or they take their medication irregularly.

It is clear, therefore, that the availability of effective preventive agents is not synonymous with effective prevention. While the conditions which account for this fact can be modified so that the incidence of rheumatic fever can be reduced, the disease will not be eradicated until a more biologic means to prevent streptococcal infections becomes available.
Wenckebach and Mobitz Type II A-V Block Due to Block Within the His Bundle and Bundle Branches
Authors: NARULA ONKAR S. , SAMET PHILIP
Published: June 2012

Fourteen patients with conduction defects were analyzed by using bundle of His (BH) recordings. The BH electrograms were validated by BH and right atrial pacing (AP). In 12 patients with Mobitz type II A-V block, failure in impulse transmission for the dropped beats was localized distal to the recording site of the BH. Three of these 12 patients showed normal QRS complexes. In two of these three, the QRS complexes remained unchanged during intermittent periods of complete heart block (CHB), and thus represent His bundle rhythm with subsidiary pacemaker arising above the bifurcation of the BH. The A-H time in this group of 12 patients ranged from 60 to 160 msec and the H-V time ranged from 40 to 90 msec. At any atrial rate (NSR or AP) conduction time through the A-V node (A-H), and His-Purkinje system (H-V) remained constant. With increasing atrial (A) rates during AP, the number of impulses blocked distal to the BH increased. At high AP rates Wenckebach phenomenon between A and BH occurred concomitantly with block distal to the BH.

Of the two additional patients studied, the one with Wenckebach type 2° A-V block during NSR and a narrow QRS complex had the delay localized between two recorded and validated BH potentials ("split" BH). The other patient, with 1:1 A-V conduction during NSR and left bundle-branch block, developed Wenckebach cycles during AP at 110 beats/min. The progressive delay in the P-R interval was localized in the His-Purkinje system (HPS) probably in the right bundle.

Our data support the clinical observations that Mobitz II A-V blocks are associated with bilateral bundle-branch block as well as with BH lesions. The ECG is of limited value in the localization of the delays occurring at two sites simultaneously: namely, in the A-V node and the HPS. Furthermore, demonstration of the Wenckebach cycles within the HPS (BH or either bundle branch), which cannot be determined from the surface ECG, has important clinical implications.
The Left Ventricular Ejection Time in Elderly Subjects
Authors: WILLEMS JOS L. , ROELANDT JOS , DE GEEST HILAIRE , KESTELOOT HUGO , JOOSSENS JOZEF V.
Published: June 2012

The left ventricular ejection time (LVET) was studied by means of the carotid artery tracing in 512 elderly subjects (205 male and 307 female) who were between 60 and 90 years old (mean age, 70.5 years). A highly significant correlation was found between heart rate (HR) and LVET. The data on these aged subjects were compared and analyzed with the results previously reported concerning young and middle-aged adults. A small but significant increase of LVET with aging, independent of changes in HR and blood pressure, could be demonstrated by multiple regression analysis. A statistically significant difference existed between the sexes. The influence on LVET of parameters other than HR was small.
Evaluation of Nitroglycerin in Angina in Patients on Isosorbide Dinitrate
Authors: ARONOW WILBERT S. , CHESLUK HERMAN M.
Published: June 2012

Seventeen male patients with angina pectoris due to coronary artery disease who had not received long-acting nitrites for at least 1 mo prior to this study were evaluated in a double-blind crossover study to investigate whether the presence of isosorbide dinitrate interfered with the effective response of exercise-induced angina to nitroglycerin administered sublingually. There was no significant difference in the duration of angina following nitroglycerin whether the patients were on no medication, sublingual placebo or sublingual isosorbide dinitrate. There was no significant difference in the blood pressure, heart rate, product of systolic blood pressure and heart rate, or electrocardiographic response after the complete relief of angina following sublingual nitroglycerin whether the patients were on no medication, sublingual placebo, or sublingual isosorbide dinitrate. These results indicate that long-acting nitrites do not cause any clinical impairment of the effective response of angina pectoris to sublingually administered nitroglycerin.
Isometric Contraction Period of the Left Ventricle in Acute Myocardial Infarction
Authors: INOUE KIYOSHI , YOUNG GEORGE M. , GRIERSON ARCHIBALD L. , SMULYAN HAROLD , EICH ROBERT H.
Published: June 2012

The usefulness of nontraumatic methods for measuring the left ventricular isometric contraction period (ICP) in myocardial infarction (MI) has been evaluated. The ICP was measured in 13 normal men and 38 patients admitted to a coronary care unit with chest pain, including 18 with acute MI, 12 with old MI, and nine with chest pain of miscellaneous origin; one of these nine was also included in the group with acute myocardial infarction. ICP was determined by three different methods: (1) time between the onset of systolic wave (A) of apexcardiogram (ACG) and the beginning of upstroke (C) of carotid pulse tracing (CPT); (2) time between A and ejection crest (E) of the ACG; and (3) time between the initial low frequency, low amplitude vibration of the first heart sound, and the C of CPT. Statistically significant differences of ICP between the normal group and the three groups of patients were demonstrated only by method 1. Likewise, acute coronary ligation in seven dogs produced characteristic changes in ICP by method 1, which were associated with a reduction in the left ventricular (LV) stroke volume, LV dp/dt, and the aortic flow velocity. The ICP obtained by method 1 appears to be of value in the bedside evaluation of acute myocardial infarction.
The Structure of the Aortic Valve in Clinically Isolated Aortic Stenosis
Authors: ROBERTS WILLIAM C.
Published: June 2012

The structure of the aortic valve at autopsy is described in 162 patients over 15 years of age with clinically isolated, severe valvular aortic stenosis with or without aortic regurgitation. The valves were congenitally unicuspid, unicommissural in 17 patients, congenitally bicuspid in 67, tricuspid in 71, and in seven the structure was uncertain. Thus, in at least 84 (52%) of the patients the valve was congenitally malformed at birth. It is proposed that minor aortic valvular cuspal inequality, also present from birth, may be an underlying malformation in some of the patients with tricuspid stenotic aortic valves. Degeneration or wear-and-tear from aging almost certainly explains aortic stenosis in most of the elderly patients. Although no patient had clinical evidence of mitral valvular dysfunction, the mitral leaflets were diffusely thickened by fibrous tissue in 26 of the 162 patients. Rheumatic disease is believed to be the cause of the valve involvement in 22 of them (the other four had congenitally bicuspid aortic valves). Rheumatic disease did not appear to be the cause of the aortic stenosis in the other 136 patients with anatomically normal mitral valves.
Comparative Quantitative Analysis of the Electrocardiogram and the Vectorcardiogram
Authors: MCCONAHAY DAVID R. , MCCALLISTER BEN D. , HALLERMANN FRANZ J. , SMITH RALPH E.
Published: June 2012

Simultaneously recorded standard electrocardiograms (ECG) and Frank vectorcardiograms (VCG) were correlated with the coronary arteriograms and the left ventriculograms of 210 patients. Quantitative criteria were applied to ECG measurements made by manual technics and to VCG measurements obtained by computer technics.

As the extent of significant arteriographic disease increased, the frequency of ECG and VCG evidence of "definite" myocardial infarction (MI) increased. The VCG was diagnostic of MI in a greater number of patients than the ECG (50 versus 39,
P
< 0.01) and excelled in the detection of multiple areas of infarction in a greater number of patients (13 versus six,
P
< 0.05). This increased sensitivity was gained in anterior, inferior, and true posterior infarcts. Excluding patients with myocardiopathy, all MIs diagnosed from the VCG and all but one from the ECG were associated with significant arteriographic disease in the distribution of the predicted nutrient artery.

Quantitative VCG analysis appears superior to the usual ECG analysis in the accurate detection of MI. When MI is diagnosed by either technic, significant associated coronary artery disease can be anticipated in a predictable anatomic distribution.
Intravascular and Extravascular Hemolysis Accompanying Extracorporeal Circulation
Authors: WALLACE HERBERT W. , BLAKEMORE WILLIAM S.
Published: June 2012

Eleven patients undergoing open heart surgery were studied by means of a technic previously developed by us to quantitate intravascular and extravascular hemolysis. Endogenous production of carbon monoxide, which correlates quantitatively with red blood cell and hemoglobin catabolism, was measured preoperatively, 5 hr postoperatively, and 24 hr postoperatively. Rates of plasma hemoglobin catabolism and intravascular hemolysis were calculated from serial plasma hemoglobin determinations. Extravascular hemolysis results from catabolism of erythrocytes damaged during perfusion and subsequently sequestered in the reticuloendothelial system. Intravascular hemolysis occurred only during perfusion and averaged 252.22 ±
se
49.64 µmoles heme. Extravascular hemolysis measured for the first 5 hr after perfusion averaged 462.48 ±
se
68.70 µmoles heme, or 64% of the total calculated red blood cell destruction. In all but one of the eight patients studied 24 hr after perfusion, heme catabolism remained elevated (mean, 46.76 ±
se
13.05 µmoles heme/hr compared to a normal value of ≦22 µmoles heme/hr), indicating that extravascular hemolysis was still occurring. This extravascular destruction probably resulted from alterations in the cell membrane induced during the pumping procedure.