bluuebunny/crossref_metadata_2025 huggingface dataset:
The Rate of Change of Left Ventricular Volume in Man
Authors: HAMMERMEISTER K. E. , WARBASSE J. R.
Published: June 2012

Because there is little quantitative information about the hemodynamics of left ventricular diastolic events in man, single-plane cineangiographic left ventricular volume curves were quantitatively analyzed at 16.6 msec intervals to evaluate the rate and amount of left ventricular filling during the early passive stage of filling and during the time of atrial contraction. The peak rate of passive diastolic filling of the left ventricle (D dV/dt), the peak rate of filling during atrial contraction (dV/dt c 'a'), and the increment in diastolic left ventricular volume due to atrial contraction (ΔV c 'a') were analyzed for a group of 110 adult patients with a variety of cardiac lesions. Normal D dV/dt, 503 ± 171 cc/sec, was significantly depressed in patients with mitral stenosis (393 ± 109 cc/sec) and coronary artery disease (394 ± 150 cc/sec). When corrected for end-diastolic volume (EDV), the resultant D dV/dt/EDV was significantly depressed in all disease states studied. D dV/dt corrected similarly for total left ventricular stroke volume (SV) was depressed from normal in patients with coronary disease, mitral stenosis, and valvular regurgitation. These data indicate that patients with coronary disease and chronic valvular disease have an abnormality in early diastolic filling of the left ventricle and that this may have a more profound effect on ventricular performance than changes in late diastolic compliance. D dV/dt has a high correlation with peak systolic ejection rate (
r
= 0.71), SV (
r
= 0.82), and EDV (
r
= 0.51).

The normal ΔV c 'a' represents 21% of the stroke volume (16% of the stroke volume if corrected for passive filling during this time period). Patients with coronary artery disease, valvular regurgitation, and aortic stenosis have an increased ΔV c'a'. Atrial contraction results in a second peak in mitral valve flow in late diastole (dV/dt c 'a'). In normal patients dV/dt c 'a' is 38% of D dV/dt, but in disease states this ratio is substantially increased. In the diseased heart atrial contraction makes a greater contribution to cardiac output than in the normal heart.
Atrial Septal Defect in Infancy
Authors: TANDON RAJENDRA , EDWARDS JESSE E.
Published: June 2012

The atrial septum was evaluated in necropsy specimens from subjects who died under the age of one year. Observations indicated that when an atrial septal defect (ASD) was present, there was commonly an associated condition. In the vast majority, the ASD was at the fossa ovalis and took the form of valvular incompetent foramen ovale. The findings strongly support the concept that an ASD at the fossa ovalis found in symptomatic infants is acquired secondary to the effects of an underlying anomaly. Overloading of the left or right atrium appears to be the mechanism resulting in the formation of an acquired ASD.

In infants with various anomalies that cause overloading of the left atrium, such as left-to-right shunts from ventricular septal defect and left-sided inflow obstruction, the incidence of a defect at the fossa ovalis was 18% and 29%, respectively.

A similar type of ASD was found in 31% of the cases with right-sided inflow or outflow obstruction.
An Electrophysiologic Approach to the Surgical Treatment of the Wolff-Parkinson-White Syndrome
Authors: SVENSON ROBERT H. , GALLAGHER JOHN J. , SEALY WILL C. , WALLACE ANDREW G.
Published: June 2012

The usefulness and limitations of electrode catheter and epicardial mapping techniques in the evaluation of the Wolff-Parkinson-White syndrome are described. In one case epicardial surface mapping was unsuccessful in localizing the accessory connection. However, a septal location was suggested by catheter recording techniques and confirmed by the point at which the surgical incision interrupted the accessory connection. In the second case catheter techniques could not confirm the role of the accessory connection in a re-entrant rhythm. Epicardial mapping of the atrium during PAT confirmed a return route to the atrium over the accessory connection, opposite the point of ventricular pre-excitation during sinus rhythm. In both cases, following surgery, epicardial maps, 12-lead ECGs and catheter recording techniques revealed no evidence of residual pre-excitation.
Echocardiographic Recognition of the Congenital Bicuspid Aortic Valve
Authors: NANDA NAVIN C. , GRAMIAK RAYMOND , MANNING JAMES , MAHONEY EARLE B. , LIPCHIK ELLIOT O. , DEWEESE JAMES A.
Published: June 2012

Twenty-one patients (age four to 25 years) with bicuspid aortic valves proved by surgery and angiography (12) or angiography alone (9) were studied by echocardiography. Seventeen patients had aortic valve disease (11 stenosis, 6 incompetence) and four had coarctation of the aorta with normally functioning aortic valves. A comparison group of 16 patients (9 with aortic valve disease and 7 without aortic valve disease) who had proven tricuspid aortic valves was also studied. Echocardiograms in tricuspid aortic valve patients showed the closed position of the cusps near the middle of the aortic lumen. In contrast marked eccentricity of the aortic valve cusp echoes in diastole could be demonstrated in all with bicuspid aortic valves. The Eccentricity Index (½ aortic lumen diameter/minimum distance of the diastolic cusp echo from the nearest aortic margin) was low (range 1.0-1.25) with tricuspid aortic valves and high (range 1.5-5.6) with bicuspid aortic valves (
P
< 0.001). This index was not significantly affected following successful valvotomy. Bicuspid aortic valve cusps showed normal systolic motion pattern resulting in marked asymmetry of leaflet images. About half of patients with bicuspid aortic valves also showed multilayered echoes in diastole in the absence of fluoroscopic evidence of valvular calcification. Echocardiography appears to be specific in the recognition of the bicuspid aortic valve.
Echocardiographic Manifestations of Left Bundle Branch Block
Authors: DILLON JAMES C. , CHANG SONIA , FEIGENBAUM HARVEY
Published: June 2012

Seventeen patients with left bundle branch block were studied using standard echocardiographic techniques employing a strip chart recorder. All 17 patients were found to have specific echocardiographic findings of abnormal septal motion uniquely different from previously described forms found in volume overload states of the right ventricle as well as coronary artery disease. The specific echocardiographic abnormality demonstrated in left bundle branch block is a very dynamic posterior motion of the interventricular septum occurring within 0.04 seconds of the onset of the QRS and preceding the anterior motion of the posterior left ventricular wall during ventricular ejection. This type of septal motion is not seen in the other forms of abnormal septal motion and appears to be specific for left bundle branch block.
The Electrophysiologic Effects of Lidocaine in Patients with Intraventricular Conduction Defects
Authors: KUNKEL F. , ROWLAND M. , SCHEINMAN M. M.
Published: June 2012

A 6 mg/kg lidocaine infusion was administered (over 22 min) to 10 patients with the electrocardiographic findings of bundle branch block. His bundle electrograms, heart rate, blood pressure, and plasma lidocaine levels were obtained before, every 5 min during, and for 20 min after the infusion was terminated. Control atrioventricular nodal conduction time (AH) was prolonged in two patients (130-175 msec) and infranodal conduction time was abnormally prolonged in four (60-100 msec). Therapeutic lidocaine levels were achieved in all patients and peak levels ranged from 3.3-11.0 µg/ml. No significant changes in mean heart rate, blood pressure, AH, His-Purkinje conduction time, or QRS duration were noted between control values and during or after the lidocaine infusion. Toxic central nervous system side effects including somnolence, dysarthria, and euphoria were noted in five subjects. Therapeutic levels of lidocaine were effective in the eradication of premature ventricular beats and safe in the sense that no higher degrees of atrioventricular or intraventricular conduction block were found; however, mild symptoms of central nervous system toxicity were commonly observed.
Beneficial Effects of Vagal Stimulation and Bradycardia During Experimental Acute Myocardial Ischemia
Authors: MYERS RICHARD W. , PEARLMAN ALAN S. , HYMAN RICHARD M. , GOLDSTEIN RICHARD A. , KENT KENNETH M. , GOLDSTEIN ROBERT E. , EPSTEIN STEPHEN E.
Published: June 2012

It is commonly believed that vagally-mediated bradycardia predisposes to ventricular fibrillation (VF) during acute myocardial ischemia. Recent experimental studies, however, have shown that bradycardia and vagal stimulation independently raise the threshold for electrically induced VF in the ischemic canine heart. To determine the influence of vagal stimulation on the spontaneous development of VF occurring during acute myocardial ischemia, open-chest dogs with acute coronary occlusion were observed with and without electrical vagal stimulation. When heart rate was allowed to fall, mean time to VF was 14.7 ± 2.1 min (
se
) in the control dogs (heart rate about 180/min), 23.4 ± 1.9 (
P
< 0.01) in the dogs with low intensity vagal stimulation (heart rate about 100/min), and 28.6 ± 0.9 (
P
< 0.001) in dogs with high intensity vagal stimulation (heart rate about 60/min). Only 10% of the control animals survived after 30 min of occlusion compared with 40% (NS) of the dogs with low intensity vagal stimulation and 71% (
P
< 0.05) of the dogs with high intensity vagal stimulation. Thus, vagal stimulation and bradycardia were associated with a postponement or prevention of VF. In a second series of animals with heart rate maintained constant by right ventricular pacing, vagal stimulation continued to exert a protective effect against the development of VF. Time to VF was increased from 11.0 ± 2.0 min in control animals to 22.6 ± 2.5 in dogs with vagal stimulation (
P
< 0.005), and percent survival was enhanced (12% in control animals versus 57% in the vagally stimulated group,
P
< 0.02). Similar results were observed in a third series of dogs in which electrical stimulation was applied to the peripheral ends of the cut cervical vagi. We conclude that vagal stimulation, with or without accompanying bradycardia, reduces the incidence of spontaneous VF in experimental coronary occlusion. Thus, enhanced vagal tone might act to reduce, rather than increase, the risk of arrhythmic death occurring during acute myocardial ischemia in man.
Comparison of the Hemodynamic Effects of Exercise and Isoproterenol Infusion in Patients with Pulmonary Valvar Stenosis
Authors: NEAL WILLIAM A. , LUCAS RUSSELL V. , RAO SATYANARAYANA , MOLLER JAMES H.
Published: June 2012

In children with congenital cardiac anomalies, isoproterenol has been used to simulate exercise. To determine if these states are comparable, 28 children with pulmonary valvar stenosis were studied by cardiac catheterization at rest, during supine submaximal exercise, and during isoproterenol infusion. Similar heart rates were obtained during exercise (142/min) and isoproterenol infusion (139/min). Cardiac index, right ventricular systolic pressure and oxygen consumption were measured during each physiologic state. The change in pulmonary valve area from rest was calculated. At similar heart rates, cardiac index was significantly greater with exercise than with isoproterenol and right ventricular systolic pressure was similar in the two states. Thus, the calculated pulmonary valve area was significantly smaller with the pharmacologically induced stress. The study indicates that several of the hemodynamic effects of isoproterenol are not comparable to those produced by exercise in patients with pulmonary valvar stenosis.
Ascending Aorta to Right Pulmonary Artery Anastomosis
Authors: REITMAN MILTON J. , GALIOTO FRANK M. , EL-SAID GALAL M. , COOLEY DENTON A. , HALLMAN GRADY L. , MCNAMARA DAN G.
Published: June 2012

An intrapericardial ascending aorta-to-right pulmonary artery anastomosis was performed in 123 patients with cyanotic congenital heart disease associated with pulmonary stenosis or atresia during the eight year period from 1964 through 1971. While there were 20 early postoperative deaths (16%), 90% (93 patients) of the 103 survivors were symptomatically improved.

In the postoperative evaluation, 74 patients (72% of the survivors) returned for follow-up examination, which included cardiac catheterization in 57. The anastomosis was nonfunctioning in ten (13.5%) of these 74 patients and in an additional 13 (17.5%) patients, clinically silent right pulmonary artery stenosis was demonstrated angiographically at the anastomosis site. Clinical improvement had been maintained in the 64 patients with an open anastomosis (audible continuous murmur or angiographically demonstrated patency) including the 13 patients with acquired pulmonary stenosis at the operative site. Persistent right pulmonary artery stenosis was demonstrated in nine of the 14 patients who had cardiac catheterization after intracardiac repair of the congenital heart defect and closure of the anastomosis, but this was insignificant in four of these nine.

The ascending aorta-to-right pulmonary artery anastomosis provides symptomatic improvement for most patients with cyanotic congenital heart disease associated with pulmonary stenosis but may produce right pulmonary artery obstruction requiring attention at the time of total intracardiac repair.
Severe Congenital Tricuspid Incompetence in the Neonate
Authors: BARR PETER A. , CELERMAJER JOHN M. , BOWDLER J. DENBY , CARTMILL TIMOTHY B.
Published: June 2012

Five neonates with congenital tricuspid incompetence due to severe tethering of the tricuspid valve to the right ventricle by abnormal chordal and papillary muscle attachments are described. The abnormality was called tricuspid valvular dysplasia (TVD) if the basal insertion of the valve was normal and the Ebstein malformation if it was displaced into the sinus portion of the ventricle.

In the two infants with isolated TVD and severe tricuspid regurgitation the functional obstruction to right ventricular outflow (ORVO) produced by the high perinatal pulmonary vascular resistance (PVR) made the exclusion of pulmonary atresia difficult, despite selective right ventricular angiocardiography.

In three infants the tricuspid valvular abnormality was associated with organic ORVO; pulmonary atresia in two and critical pulmonary valve stenosis in one. In the two infants with pulmonary atresia and intact ventricular septum (IVS) the severe tricuspid incompetence produced a clinical, radiological and hemodynamic profile which was clearly different from that usually seen in infants with pulmonary atresia and IVS and a normal right ventricular cavity (type 2 of Greenwold).
The Adequacy of Subendocardial Oxygen Delivery
Authors: BRAZIER JOHN , COOPER NORMAN , BUCKBERG GERALD
Published: June 2012

The interactions of determinants of subendocardial oxygen delivery (flow and oxygen content) and oxygen demand were studied. In open chest dogs, oxygen requirements were increased with aortic stenosis and oxygen delivery reduced with normovolemic anemia. We estimated potential subendocardial flow from a Diastolic Pressure Time Index (DPTI) and oxygen demands from the Tension Time Index (TTI), and detected ischemia with endocardial (Endo) and epicardial (Epi) electrocardiograms (ECG). Subendocardial oxygen delivery per unit of TTI was significantly lowered and Endo ECGs showed ischemia (ST elevation) when Endo/Epi flow ratios (microsphere method) fell below 1.0 (
P
< 0.001). Ischemia occurred without anemia (Hgb > 10 g %) in severe aortic stenosis; with mild anemia (Hgb 5-10 g %) and mild aortic stenosis; and with severe anemia (Hgb < 5 g %) without aortic stenosis. Ischemic Endo ECGs occurred with mild supravalvar aortic stenosis and mild anemia despite a 63% (92 to 150 cc/100g/min) average increase in subendocardial flow while Epi ECGs remained normal. Altered flow distributions and abnormal ECGs were always predictable from the ratio: DPTI x O
2
content (Supply)/TTI (Demand). These determinants of Supply and Demand are readily obtained from measurements of hemoglobin, saturation, and blood pressure.
Evaluation of Subendocardial Ischemia in Valvar Aortic Stenosis in Children
Authors: LEWIS ALAN B. , HEYMANN MICHAEL A. , STANGER PAUL , HOFFMAN JULIEN I. E. , RUDOLPH ABRAHAM M.
Published: June 2012

An index of myocardial oxygen supply/demand was calculated from the left ventricular and aortic pressure tracings in 80 infants and children with isolated valvar aortic stenosis. Supply was estimated by multiplying the area between aortic and left ventricular pressures during diastole (DPTI) by arterial oxygen content (C). Demand was estimated from the area under the left ventricular tracing during systole (SPTI). The oxygen supply/demand ratio was expressed as: DPTI X C/SPTI. A ratio <10 has been shown experimentally in animals to be associated with reduced subendocardial flow. With severe stenosis, i.e., aortic valve area (AVA) <.7 cm
2
/m
2
, an increasing number of patients develop ratios <10. Patients with AVA <.7 cm
2
/m
2
but heart rates <100/minute maintain adequate ratios whereas patients with heart rates >100/minute and severe stenosis all have ratios consistent with subendocardial ischemia. Supply/demand ratios <10 are usually associated with significant T wave abnormalities on the ECG while patients with normal T waves generally have ratios >10. It is concluded that in severe valvar aortic stenosis heart rate is a critical factor in the development of a reduction in the oxygen supply/demand ratio consistent with subendocardial ischemia. Exercise induced tachycardia may be useful in identifying patients with severe valvar aortic stenosis and borderline ischemia who have normal T waves at rest.
I. Apologia
Authors: BUCHWALD HENRY , MOORE RICHARD B. , VARCO RICHARD L.
Published: June 2012

The authors have now had ten years of clinical experience with the partial ileal bypass operation for management of the hyperlipidemias. The human trial was preceded by and has been continuously complemented by research in the animal laboratory in an effort to provide a metabolic data base which will facilitate understanding of the rationale and effects of this means of lipid lowering therapy. In addition, the determination of cholesterol dynamics as influenced by partial ileal bypass has been studied in the clinical setting. Other independent investigators have published in this field confirming and extending our findings and, at times, differing in their results and conclusions. We have attempted both to review the extensive past literature in this area and to add previously unpublished original material in a three-part presentation: Part I, Apologia; Part II, Laboratory Experience; and Part III, The Clinical Status of the Partial Ileal Bypass Operation. At a time when the medical community must come to grips with the question of whether lipid lowering will influence the atherosclerotic risk rate, this task was undertaken in order to offer a comprehensive overview of what are the effective and safe means available to achieve lipid reduction.
Effect of Inotropic Agents on the Localized Dyskinesis of Acutely Ischemic Myocardium
Authors: KERBER RICHARD E. , ABBOUD FRANCOIS M. , MARCUS MELVIN L. , ECKBERG DWAIN L.
Published: June 2012

The response of the segmental dyskinesis of acutely ischemic myocardium to inotropic agents has not been well characterized. We studied this in detail in open-chest anesthetized dogs. Acute myocardial ischemia was produced by coronary ligation and confirmed by histologic studies. Ultrasound recordings obtained by direct reflection off the ischemic posterior wall revealed characteristic dyskinesis: aneurysmal bulging during isometric contraction and markedly reduced mean posterior wall velocity (PWVm), and excursion during ventricular ejection. Isoproterenol (I), norepinephrine (N), ouabain (O), glucagon (G), and propranolol (P) were then administered intravenously in graded doses. The response to these agents consisted of two discordant elements. There was a significant (
P
< 0.01) increase in aneurysmal bulging during isometric contraction with isoproterenol (5 ± 0 to 6 ± 0 mm) and ouabain (4 ± 0 to 5 ± 0 mm). However, during the ventricular ejection phase PWVm increased with isoproterenol (12 ± 1 to 26 ± 2 mm/sec), glucagon (12 ± 2 to 22 ± 2 mm/sec), norepinephrine (12 ± 1 to 17 ± 1 mm/sec), and ouabain (8 ± 1 to 12 ± 2 mm/sec). Simultaneous hemodynamic measurements showed the drugs elevated cardiac output (G > I > 0) and left ventricular dp/dt ( I > G > N).

Inotropic agents thus have two opposing effects on the dyskinesis of acutely ischemic myocardium: increased aneurysmal bulging during isometric contraction, but improved wall velocity during ventricular ejection. The latter contributes to the drug-induced improvement in over-all ventricular performance and also indicates that acutely ischemic myocardium retains the capacity to respond to pharmacologic stimuli.
The Inotropic Effects of the Calcium Ionophore X-537A in the Anesthetized Dog
Authors: DE GUZMAN NORBERTO T. , PRESSMAN BERTON C.
Published: June 2012

The ability of ion permeability-inducing agents (ionophores) to complex and transport cations and amines across membranes has provided a novel approach for the pharmacological modification of biological systems. Of particular interest is X-537A, since it not only transports alkali ions but compared to most of the known ionophores it is unusually efficient in transporting calcium as well as catecholamines. The cardiovascular effects of this agent were studied in normal anesthetized dogs. X-537A produced a dramatic augmentation of myocardial contractility with up to 210% increases in max dP/dt after intravenous doses of 1.0-1.5 mg/kg. The moderate dose of 0.5-0.75 mg/kg X-537A induced significant increases in max dP/dt (68%,
P
< .001), isometric ventricular segmental tension (IVST) (79%,
P
< .01), peak dT/dt (65%,
P
< .05), cardiac output (44%,
P
< .001), aortic systolic (18%,
P
< .001) and diastolic (15%,
P
< .001) pressures, pulse pressure (28%,
P
< .001), left ventricular systolic pressure (18%,
P
< .001), and decrease in total peripheral resistance (23%,
P
< .05) without significant changes in heart rate and atrioventricular conduction. Beta-blockade with large doses of propranolol showed 20% suppression of the cardiac inotropism of X-537A. The action of X-537A is typically rapid with a smooth continuous progression until maximal response is attained in 10-15 minutes, sustained for about one hour, then gradually subsides during the third hour. Such ideal cardiovascular effects of X-537A portend a profound therapeutic potential in cases of cardiac decompensation and circulatory compromise. X-537A may also prove to be a valuable tool for probing the complex factors influencing myocardial contractility.
Biventricular Cineangiography in the Evaluation of Patients with Asymmetric Septal Hypertrophy
Authors: REDWOOD DAVID R. , SCHERER JAMES L. , EPSTEIN STEPHEN E.
Published: June 2012

Echocardiographic studies have demonstrated that the characteristic anatomic defect in idiopathic hypertrophic subaortic stenosis (IHSS) is asymmetric septal hypertrophy (ASH). Although echocardiographic diagnosis of ASH is extremely sensitive, occasionally adequate echocardiograms cannot be obtained. Moreover, echocardiographic assessment of the extent of the underlying cardiomyopathic process, known to be distributed nonuniformly, is limited to evaluation of the upper part of the ventricular septum and the posterobasal left ventricular (LV) free wall. To determine if a specific angiographic marker of ASH can be identified even in the absence of LV outflow obstruction, and to delineate the extent and degree of cardiomyopathic involvement of the ventricular septum and LV free wall in patients with ASH, septal and LV wall configuration and thickness were measured using simultaneous biventricular cineangiography. The ventricular septum was thicker in 16 patients with ASH (avg. 15.2 ± 1.5 mm) and in six patients with concentric left ventricular hypertrophy (LVH) due to aortic valve disease (avg. 12.8 ± 1.1 mm) than in seven normal subjects (avg. 6.7 ± 0.4 mm,
P
< 0.001). In normal subjects and in patients with concentric LV hypertrophy, the walls of the ventricular septum were parallel. In contrast, the walls diverged in ASH so that septal width increased significantly inferiorly. Thus, the ratio of upper to lower septal width was greater than 0.8 (avg. 1.04 ± 0.06 mm) in normals and LVH patients but less than 0.77 (avg. 0.70 ± 0.01 mm,
P
< 0.001) in ASH patients. Furthermore, upper septal width and the ratio of upper to lower septal width in ASH were significantly greater in seven patients with LV outflow obstruction than in six patients without obstruction, suggesting that the upper septum bulges into the LV outflow tract to a greater extent in obstructive ASH. In addition, the LV free wall in ASH was nonuniformly thickened, whereas in LVH the hypertrophy was uniform. We conclude that angiographic delineation of the septum and LV free wall 1) demonstrates abnormalities that distinguish ASH from normal and concentrically hypertrophied hearts, 2) demonstrates abnormalities that distinguish obstructive from nonobstructive ASH, and 3) aids in characterizing the distribution of myopathic involvement in patients with ASH.
Selective Coronary Arteriography in Young Men A Follow-Up of 449 Patients
Authors: LIM JUAN S. , PROUDFIT WILLIAM L. , SONES F. MASON
Published: June 2012

The prognosis for 449 young men with normal, mildly abnormal, and obstructive arteriograms with and without internal mammary artery implants was studied. Prognosis for patients with normal arteriograms was good in regard to incidence of infarction and mortality. In 30 patients with mildly abnormal arteriograms there appeared to be a relatively higher incidence of myocardial infarction, although the total number of patients in this category was small. In 116 young men with obstructive coronary disease the 5-year survival rate was 66.8%. The 5-year mortality in patients with single vessel involvement was 8.8% and in those with multiple vessel disease mortality was 37%. The mortality was 6.8% each year among survivors in this group of patients with both single and multiple vessel disease. The prognosis was worse when there was multiple vessel involvement, when there was generalized decrease in contractility shown by the left ventriculogram, or when the electrocardiogram showed evidence of myocardial infarction. The influence of internal mammary artery implantation could not be accurately assessed because of the small number of cases and the substantial number of patients who did not have postoperative internal mammary arteriography.
A Sector Scanner for Real Time Two-Dimensional Echocardiography
Authors: GRIFFITH JAMES M. , HENRY WALTER L.
Published: June 2012

During the past several years one-dimensional pulse-echo ultrasound techniques have proven extremely useful in cardiac diagnosis. A one-dimensional system, however, only visualizes structures lying along a single straight line. The spatial relationships of the various cardiac structures are therefore not so easily defined as with two-dimensional systems which display the heart by constructing a plane image composed of many straight lines. We have developed a sector scanning system for obtaining two-dimensional echocardiograms in real time using ultrasonic pulse-echo techniques. Images are produced by angling rapidly a single transducer through a 30-degree sector from a fixed spot (between ribs) on the patient's chest. Thirty complete sectors (or frames) are produced per second. The use of a large diameter transducer ensures that signal strength is good and cardiac structures, including endocardium, can be visualized. Other advantages include high transducer sensitivity, real time imaging and easy visualization of various regions of the heart. Experience with more than 100 patients indicates that diagnostic quality two-dimensional echocardiograms can be readily obtained in essentially the same patients from whom one-dimensional echocardiograms are recorded and can usually be performed in less time.
Thrombotic Calcific Mitral Stenosis
Authors: WOOLEY CHARLES F. , BABA NOBUHISA , KILMAN JAMES W. , RYAN JOSEPH M.
Published: June 2012

We compared the morphology of the calcific stenotic mitral valve (CSMV) with noncalcific stenotic mitral valves (NCSMV) removed at surgery; control valves were obtained at autopsy. X-rays of the excised valves permitted localization and quantitation of calcification. A classification of CSMV applicable to noninvasive techniques based on this methodology is presented. Moderate to heavily CSMV had greater weight, volume, specific gravity, weight per area, with smaller orifice size when compared with NCSMV and controls. Leaflet mobility was obliterated in moderate to heavily CSMV, while most NCSMV had some degree of leaflet mobility.

Surface morphology was strikingly different in CSMV with 1)
surface ulceration
, due to eruption of the underlying calcific focus through valvular endothelium, 2)
thrombosis
in the areas of ulceration ( associated with symptomatic arterial embolization in four patients), 3)
whisker formation
, filamentous stalks along the line of valve closure.

Calcification in the CSMV is viewed as an active, progressive process resulting in altered physical characteristics of the valve, progressive leaflet immobility and orifice narrowing, and eruptive surface changes with thrombus formation and arterial embolization arising from the CSMV itself. Clinical implications and a rationale for more precise classification of mitral stenosis on the basis of valvular calcification are presented.
Coarctation of the Aorta with Congenital Mitral Regurgitation
Authors: FREED MICHAEL D. , KEANE JOHN F. , VAN PRAAGH RICHARD , CASTAÑEDA ALDO R. , BERNHARD WILLIAM F. , NADAS ALEXANDER S.
Published: June 2012

Among 861 infants and children with coarctation of the aorta examined between 1950 and 1973, inclusive, 18 (2.1%) also had congenital mitral regurgitation (MR).

Resection of the coarctation of the aorta was performed in 16 of these 18 patients (89%). There were three operative deaths early in the series, giving a total mortality rate of 18% since 1950. Over the past decade, mortality in this group has been reduced to zero. Mitral valve replacement was performed following resection of the coarctation in 2/13 patients (13%), both successfully. The follow-up of the 13 postoperative patients and the two who have not undergone surgery has ranged from 5 to 18 years, with a median of nine years. At the last examination, an appreciable pressure gradient persisted between the right arm and the legs in 4/15 patients (27%). Weight remained below the third percentile in none. The clinical picture of congestive heart failure was present in none, but significant cardiomegaly was found radiologically in 11/15 (73%) and the electrocardiogram remained abnormal in 8/15 (53%). Over the period of follow-up, the MR became clinically worse in 4/15 patients (27%), remained unchanged in 7/15 (47%), and improved following resection of the coarctation in 4/15 patients (27%).

The pathologic anatomy of congenital MR associated with coarctation of the aorta was reviewed and classified. Two unique cases were presented — rupture of chordae tendineae and perforation of the posterior leaflet, both apparently congenital. When mitral surgery becomes necessary, an understanding of the pathologic anatomy of congenital MR may well make it possible to avoid mitral valve replacement in selected cases.
The Missing Waveform Information in the Orthogonal Electrocardiogram (Frank Leads)
Authors: KORNREICH F. , BLOCK P. , BRISMEE D.
Published: June 2012

Nine surface electrocardiograms recorded on the thoracic surface at fixed and identical locations in 412 individuals were found to account for the maximal useful waveform information available in each individual. In other words, nine waveforms were capable of resynthesizing any waveform recorded on their thoracic surface. These nine waveforms were then submitted to multivariate statistical procedures and their diagnostic performance compared to the Frank leads on which the same procedures were applied. Before the data were fed into the computer, all waveforms were time-normalized and divided into eight equal parts, yielding 72 variables and 24 variables for the nine lead system and the Frank leads, respectively, for each individual.

In this paper we attempted to discriminate between normal subjects and patients with documented angina pectoris (typical history and positive coronary angiography); myocardial infarction was excluded in these patients. Only the resting QRS complex was considered. With the 9-lead system, keeping the specificity (true negatives) at 90%, the sensitivity (true positives) is 76%; with the Frank leads, the same specificity yielded a sensitivity of 49%. The repeatability of the results on new independent controls was also found very satisfactory.

The discrimination between patients with angina pectoris on one hand and left ventricular hypertrophy and myocardial infarction on the other hand resulted in a performance level of 89% and 87%, respectively, for the 9-lead system. A good correlation was also found between the extent of the coronary lesions (number of coronary vessels involved) and the fraction of correctly diagnosed patients.

The present study concluded that the retrieval of more complete surface information results in an evident improvement of the diagnostic performance of electrocardiography.
De Subitaneis Mortibus
Authors: JAMES THOMAS N. , ARMSTRONG RICHARD S. , SILVERMAN JAY , MARSHALL THOMAS K.
Published: June 2012

Special studies of the heart were conducted at necropsy of two young soldiers who had died suddenly and unexpectedly. In the first case there was extensive myocarditis, an atretic main left coronary artery, special large interarterial anastomoses including the sinus node artery, old fibrosis in the His bundle and recent hemorrhages in the internodal pathways. In the second case there was a markedly narrowed atrioventricular (A-V) node artery with disruptive fibrosis of the left and right bundle branches, and lacunar faults in the central fibrous body near the A-V node. These dissimilar findings are discussed relative to the pathophysiological basis of sudden death.
Echocardiographic Detection of Supravalvular Aortic Stenosis
Authors: USHER BRUCE W. , GOULDEN DUDLEY , MURGO JOSEPH P.
Published: June 2012

The echocardiographic features of supravalvular aortic stenosis of the segmental or hourglass variety is described for the first time. Utilizing a strip recorder and an M mode or sector scan the diameter of the aortic lumen is demonstrated to narrow at the stenotic area just distal to the aortic valve. As the transducer sweeps further cephalad the aortic root lumen widens to a normal diameter.
The Therapeutic Range of Gitalin (Amorphous) Compared with Other Digitalis Preparations
Authors: BATTERMAN ROBERT C. , DEGRAFF ARTHUR C. , ROSE O. ALAN
Published: June 2012

The therapeutic ranges of amorphous gitalin, digitalis leaf, digitoxin and Digoxin were compared in terms of rapid and slow methods for initial digitalization and maintenance of the digitalized patient. Gitalin (amorphous) possesses a therapeutic range greater than any available digitalis preparation or glycoside. In a group of 18 ambulatory patients, gitalin (amorphous) was found to possess an average of 41 per cent increase in therapeutic range when compared with digitalis leaf. Advantages of the use of gitalin (amorphous) as compared with other digitalis preparations are discussed.
The Spatial Vectorcardiogram Obtained by Use of a Trihedron and Its Scalar Comparisons
Authors: DUCHOSAL PIERRE W. , GROSGURIN JEAN R.
Published: June 2012

The spatial vectorcardiogram is supposed to represent the path of the cardiac vector viewed from a rather large distance. With this in mind, the authors propose a vectorcardiographic method based on a trirectangular trihedron. Comparisons are made between calculated scalar leads derived from the spatial vectorcardiogram, and real scalar leads recorded from the subject. In case of concordance the hypothesis of a single instantaneous cardiac vector within an homogeneous conducting medium is verified. This was found to hold for most circumstances. However, for those instances in which discrepancies arose another hypothesis is advanced.
The Value of High Fidelity Electrocardiography Using the Cathode Ray Oscillograph and an Expanded Time Scale
Authors: LANGNER PAUL H.
Published: June 2012

The cathode ray is practically free from inertia and therefore an ideal instrumentality for studying variations in electrical potential. A cathode ray oscilloscope with an amplifier system of high frequency response and an expanded time scale, 330 mm. per second, were employed to record electrocardiograms. Such tracings revealed considerable notching, slurring, and other peculiarities not seen in the conventional electrocardiographic records on the same individuals. An instrument should have a frequency response curve flat to well over 330 cycles per second to record faithfully the human electrocardiogram. This is much higher than the frequency response of instruments usually used for electrocardiography.
The Tricardiograph: A Rapid Screening Method for Cardiac Disease
Authors: BRANDT J. LEONARD , DOCK WILLIAM , LANDSMAN ROBERT , PASSANNANTE CHARLES
Published: June 2012

To take slit kymograms of the left hemithorax on 6½ by 8½ inch film, a carrier was designed which can be fitted to the arms of a fluoroscope, replacing the screen. On the lateral and cephalad corner, six seconds of galvanometer trace are recorded, the slit kymograph being exposed during the interval from 3.0 to 4.5 seconds. With two galvanometers, the electrocardiogram and ballistocardiogram can be inscribed, thus timing the motions of the heart border, and permitting correlation of ballistic phenomena with ventricular ejection. This device also has promise as a screening method for detecting cardiac disease.
The Effect of Aging and of the Development of Disease on the Ballistocardiogram
Authors: STARR ISAAC , HILDRETH E. A.
Published: June 2012

Second ballistocardiograms were taken on 80 subjects who were part of the series from which the original normal standards were secured in 1937, 1938 and 1939. Sixty-five of these subjects had retained good health during the long interval; by a comparison between their old and new records, the effect of "normal" aging on the ballistocardiogram has been determined. Fifteen subjects lost their health during the interval and two of them have died since the second test. The evolution of their ballistocardiograms has been compared with the development of their disabilities.
The Tissue Distribution and Excretion of Radioactive Digitoxin
Authors: FISCHER C. S. , SJOERDSMA A. , JOHNSON R.
Published: June 2012

The tissue distribution and excretion of radioactive digitoxin and its metabolites were studied in normal rats and cats and in rats with dietary induced myocardial lesions. The prolonged cardiac and renal retention of digitoxin and its derivatives, associated with the persistence of these substancces in the excreta of sensitive animals, supports the concept of storage as an explanation for the cumulative action of certain of the cardiac glycosides. There is a suggestive increase in digitoxin metabolism in heart failure.
Obesity, Fat Metabolism and Cardiovascular Disease
Authors: GOFMAN JOHN W. , JONES HARDIN B.
Published: June 2012

Lipoproteins of the S
f
12-100 class, representing only about 10 to 15 per cent of the serum cholesterol, are strongly associated with atherosclerosis. The major independent contributions to this association are from the S
f
12-20 lipoproteins and the S
f
35-100 lipoproteins. The S
f
20-35 lipoproteins are primarily associated by virtue of their intercorrelation with the other classes. Obesity is moderately associated with the S
f
35-100 and definitely, but to a lesser degree, with the S
f
12-20. The association of obesity with total serum cholesterol is so low as to obscure the stronger association with the S
f
35-100 lipoproteins. The relationship of the S
f
12-100 lipoproteins with obesity may be adequate to explain the major share, if not all, of the association of obesity with atherosclerosis. The control of obesity should therefore be a prime consideration in the management of atherosclerosis and its complications.
Use of a Combination of Anion and Cation Exchange Resins in the Treatment of Edema and Ascites
Authors: MARTZ B. L. , KOHLSTAEDT K. G. , HELMER O. M.
Published: June 2012

A mixture of a carboxylic acid type of cation exchange resin and a weakly basic anion exchange resin has been used successfully to control the edema of 42 patients with congestive heart failure and the ascites of 14 patients with cirrhosis of the liver. Approximately one-third of the cation exchanger was supplied in the potassium cycle.

Inclusion of the anion exchange resin resulted in a greater sodium uptake per gram of resin and apparently decreased the incidence of disturbances in acid-base balance in patients with impaired renal function who were treated with resins.
Studies of Plasma Quinidine Content
Authors: SAMPSON JOHN J. , FOREMAN HARRY , SOLOMON BERTRAM C.
Published: June 2012

Quinidine sulfate, orally administered in tablets coated with a material delaying their absorption, produces concentration curves in the blood serum similar to those of uncoated tablets. However, there is a delay in the appearance and the attaining of maximum concentrations with the coated tablets, although higher levels may persist for 12 hours. Defects in coating may cause faulty failure of absorption. The advantages of using such a preparation of quinidine are: (1) avoidance of nausea in susceptible persons, (2) providing effective concentrations of the drug during the night and thereby preventing nocturnal attacks of arrhythmias, and (3) providing greater concentrations of the drug in the morning, when attempts at conversions of arrhythmias may require therapy over several days or more.
The Effect of Sympathectomy for Essential Hypertension on the Hallucal Circulation
Authors: MENDLOWITZ MILTON , TOUROFF ARTHUR S. W.
Published: June 2012

The effects of sympathectomy on the hallucal circulation were studied in patients with essential hypertension. Return of sympathetic nerve function of variable degree could be demonstrated in every patient. An increase in non-neurogenic or intrinsic resistance was also found to be attributable to the sympathectomy. This could not be reversed by benzodioxane and was therefore probably not produced by circulating epinephrine. The possible mechanisms of this phenomenon are discussed.
Observations Concerning the Metabolism of Cholesterol in the Hypo- and Hyperthyroid Rat
Authors: ROSENMAN RAY H. , FRIEDMAN MEYER , BYERS SANFORD O. , Shibata Eichi
Published: June 2012

The administration of thiouracil induced a rise and administration of thyroid substance a decrease of the plasma cholesterol concentration in rats. The concentration and daily output of bile cholesterol was markedly reduced in hypothyroid rats and markedly increased in hyperthyroid rats. Evidence is presented which suggests that the rate of synthesis of cholesterol is significantly increased in the hyperthyroid rat and decreased in the hypothyroid rat.
The Abnormal Serum Lipid Pattern in Patients with Coronary Arteriosclerosis
Authors: STEINER ALFRED , KENDALL FORREST E. , MATHERS JAMES A. L.
Published: June 2012

Studies in experimental arteriosclerosis have indicated that the relative level of serum lipid phosphorus may be as significant a factor as the absolute level of serum cholesterol in the production of arterial lesions. For this reason, the serum lipid pattern of 82 patients with coronary arteriosclerosis has been compared with that of 112 healthy adults. An elevation of the serum cholesterol, serum lipid phosphorus and the serum cholesterol-lipid phosphorus molar ratio has been found in most of the patients with coronary arteriosclerosis.
Mechanism of Iodide Action on Cholesterol Metabolism
Authors: BROWN HELEN B. , PAGE IRVINE H.
Published: June 2012

Iodide retards or prevents hypercholesterolemia and the development of experimental atherosclerosis in rabbits. "Protection" is estimated from reduction of plasma and/or hepatic cholesterol. Small doses of iodide do not "protect." Iodide in large doses prevents the hypercholesterolemia resulting from exogenous cholesterol and reduces hepatic cholesterol. This effect is independent of the thyroid gland and is not related to "thyroxin-like" plasma iodine. The influence of iodide on cholesterol metabolism seems to be related to the presence of a butanol-insoluble protein-bound iodine compound in the plasma.
The Syndrome of Short P-R Interval Normal QRS Complex and Paroxysmal Rapid Heart Action
Authors: LOWN BERNARD , GANONG WILLIAM F. , LEVINE SAMUEL A.
Published: June 2012

A short A-V conduction time, whether present with normal or with abnormal QRS complex, is associated with an increased incidence of paroxysmal rapid heart action. There are a considerable number of patients who have a short P-R interval, normal QRS complex and bouts of tachycardia. They are usually females, in middle life, devoid of organic heart disease and exhibit a snapping apical first heart sound. They do not demonstrate any of the features of anomalous A-V conduction. Evidence is presented suggesting the operation of endocrine and autonomic nervous system factors in the genesis both of the short P-R interval and the tachycardia.
Frontal and Sagittal Electrocardiograms of Normal and Hypertensive Subjects during an Experimentally Produced Phase of Lowered Blood Pressure
Authors: BRUMLÍK JOSEPH , KOSSMANN CHARLES E.
Published: June 2012

Reduction of the blood pressure in normal and hypertensive subjects by intravenous pyrogen caused the electrocardiograms to assume a more abnormal configuration as judged by present criteria of electrocardiographic normality. A temporary reduction of the blood pressure by the intravenous administration of tetraethylammonium chloride caused only minor and variable modifications of the electrocardiogram. The results of the experiments as done do not support the concept of strain as applied to certain electrocardiographic abnormalities which occur in the course of hypertension.
Arterial Hypertension in Dogs
Authors: SCHROEDER HENRY A. , GOLDMAN MELVIN L.
Published: June 2012

Various methods were devised in attempts to produce chronic hypertension in dogs. The induction of anxiety was unsuccessful. Bilateral renal denervation combined with injections of epinephrine appeared to produce temporary hypertension. Permanent hypertension was induced by unilateral renal ischemia with the other kidney left intact only in dogs of nervous temperament. Certain dogs were extremely resistant to the development of hypertension even when several methods were combined. Neurogenic hypertension induced by section of the moderator nerves is probably a true hypertension. It is obvious that the host factor may be as important as the method employed.
The Effect on Blood Pressure in the Right Heart, Pulmonary Artery and Systemic Artery of Cardiac Standstill Produced by Carotid Sinus Stimulation
Authors: DOWLING CHARLES V. , SMITH WARREN W. , BERGER ADOLPH R. , ALBERT ROY E.
Published: June 2012

In two patients with hypersensitive carotid sinus syndrome, cardiac standstill was induced while pressures were recorded in the pulmonary and femoral arteries and right heart. With onset of ventricular standstill, pressures in the right atrium and right ventricle equalized and gradually increased, that in the femoral artery decreased, and that in the pulmonary artery-fell until it became equal to right ventricular pressure, and then increased commensurately with it. All pressures then approached a uniform magnitude asymptotically: this uniform pressure is believed to correspond to the "static pressure." The manner in which the respective pressures returned to normal with resumption of normal cardiac rhythm is described, and certain unexpected findings are discussed.