bluuebunny/crossref_metadata_2025 huggingface dataset:
Primary Pulmonary Hypertension
Authors: WAGENVOORT C. A. , WAGENVOORT NOEKE
Published: June 2012

Morphologic and morphometric studies were carried out on pulmonary vessels in lung tissue from 156 patients, for whom a diagnosis of primary pulmonary hypertension had been made. This material was collected from 51 medical centers. Chronic pulmonary thromboembolism can be recognized by organizing thrombi, patchy intimal fibrosis, and intra-arterial septa. The media is only slightly thicker than normal; in 31 of the 156 cases the vascular lesions corresponded to this pattern. Other conditions such as chronic pulmonary venous hypertension, pulmonary veno-occlusive disease, sarcoidosis, chronic bronchitis, and pulmonary schistosomiasis could also be classified from the morphologic criteria. The largest group comprised 110 cases showing medial hypertrophy, laminar intimal fibrosis, and often fibrinoid necrosis, arteritis, and plexiform lesions. These alterations suggest that they were initiated by vasoconstriction. In children the sex ratio is equal; in adults there are almost four females to one male. In these patients with vasoconstrictive primary pulmonary hypertension, various stimuli are likely to bring about vasoconstriction in the presence of a pronounced pulmonary vascular hyperreactivity. A review of 602 cases from the literature is given.
Epinephrine Infusion in Man
Authors: SALZMAN STEPHEN H. , WOLFSON STEVEN , JACKSON BRUCE , SCHECHTER ELIOT
Published: June 2012

A standard test was designed for measurement of the effect of epinephrine infusion on systolic time intervals in 14 normal subjects as a dose-response phenomenon. In order that we might examine the sensitivity of the test, it was applied in nine patients with idiopathic hypertrophic subaortic stenosis.

Normal subjects had a characteristic response—a progressive shortening of the duration of electromechanical systole, left ventricular ejection time, and pre-ejection period. Their left ventricular ejection time, corrected for heart rate, did not change. Patients with idiopathic hypertrophic subaortic stenosis responded to epinephrine infusion with paradoxical lengthening of their left ventricular ejection time, corrected for heart rate. After beta blockade (with propranolol), reinfusion of epinephrine shortened the left ventricular ejection time, corrected for heart rate, to normal levels.
Adenyl Cyclase and Cyclic AMP
Authors: EPSTEIN STEPHEN E. , LEVEY GERALD S. , SKELTON C. LYNN
Published: June 2012

The actions of many hormones may be related to their capacity to increase adenyl cyclase activity in their target organs. The evidence indicating that catecholamines and glucagon augment myocardial contractility by enhancing the activity of myocardial adenyl cyclase is summarized. Furthermore, data are presented suggesting that the inotropic actions of epinephrine and glucagon ultimately may be due to an increase in sarcotubular calcium stores, an effect that appears to be related to activation of an adenyl cyclase pool localized in the sarcoplasmic reticulum. Other hormones that may alter contractility through actions on the adenyl cyclase-cyclic AMP system are thyroid hormone, histamine, prostaglandin, and acetylcholine. Chronic cardiac decompensation in both the experimental animal and in man diminishes the effectiveness of glucagon as an inotropic agent and interferes with the mechanisms by which glucagon acts to enhance the activity of myocardial adenyl cyclase, changes that may be causally interrelated. Although an understanding of the adenyl cyclase system would seem to be extremely important for an understanding of the basic mechanisms responsible for modulating the intensity of the contractile state of the heart, further investigations are necessary for complete validation of this hypothesis.
Exchangeable Sodium and Blood Volume in Normotensive and Hypertensive Humans on High and Low Sodium Intake
Authors: BROWN WALTER J. , BROWN FAITH K. , KRISHAN IQBAL
Published: June 2012

Eight normotensive and eight essential hypertensive humans were studied when on high and low sodium intake. Total 24-hr exchangeable body sodium, blood volume, serum sodium concentration, hematocrit, body weight, and mean arterial pressures, when the subjects were supine and upright, were measured. Plasma and nonplasma sodium fractions, nonplasma weight, and plasma, cell, and whole blood volumes, as referred to body weight and height, were calculated. Changes in these parameters with diet were also calculated. Specific differences between normotensives and hypertensives were found, in absolute values and with changes with diet. The hypertensives fell into two groups with regard to exchangeable sodium: in four the values varied with diet and in the other four, the values remained low regardless of diet. The "variable-sodium" patients had high upright arterial pressures when on high salt intake and normal upright pressures when on low salt intake. "Low-sodium" patients had high arterial pressures on both diets. Changes in upright pressures of hypertensives correlated significantly (r = 0.73) with changes in nonplasma exchangeable sodium.
Echocardiographic Recognition of Mitral-Semilunar Valve Discontinuity
Authors: CHESLER ELLIOT , JOFFE HYMIE S. , BECK WALTER , SCHRIRE VELVA
Published: June 2012

The angiographic recognition of mitral-semilunar valve discontinuity is a strong indication of origin of both great vessels from the right ventricle. This study shows that the same finding may be elicited by echocardiography, whether the great vessels are normally related or transposed. When mitral-semilunar valve continuity is present, the mitral valve echo at the onset of systole is continuous with and at the same depth as echoes from the posterior margin of the aorta (the great vessels being normally related) or from the pulmonary artery (the great vessels being transposed). In five cases where both great vessels originated from the right ventricle, echocardiography demonstrated mitral-semilunar valve discontinuity, with the posterior border of the adjacent great vessel lying anterior to the mitral valve echo. The degree of separation measured on the angiogram and by ultrasound was virtually identical. This atraumatic technique is a valuable adjunct to the evaluation of patients with complex congenital malformations, particularly when mitral-semilunar valve relationships are difficult to assess angiographically.
Radioisotopic Angiocardiography
Authors: KRISS JOSEPH P. , ENRIGHT LEE P. , HAYDEN WILLIAM G. , WEXLER LEWIS , SHUMWAY NORMAN E.
Published: June 2012

Radioisotopic angiocardiography has been performed in 120 patients after the intravenous injection of
99m
Tc pertechnetate. A scintillation camera and a variable time-lapse videoscintiscope were used. The results indicate that the method permits identification and physiologic assessment of a wide variety of congenital and acquired cardiovascular lesions, including septal defects, valvular stenosis and incompetence, aneurysm, tumor, venous obstruction, ventricular hypertrophy, and effusion. Emphasis particularly is given, therefore, to the wide scope of applicability of the procedure.

The diagnostic criteria employed for a representative group of these lesions are presented together with illustrative examples to demonstrate the type and quality of the information which may be obtained with the method. The procedure is rapid and safe and does not require hospitalization, heart catheterization, or special preparation of the patient, advantages which favor its use as a diagnostic screening test. In addition to its diagnostic uses, radioisotopic angiography may offer a useful and convenient method of assessing the effects of therapy or of following the course of disease.
Comparison of Human Ventricular Activation with a Canine Model in Chronic Myocardial Infarction
Authors: DANIEL THOMAS M. , BOINEAU JOHN P. , SABISTON DAVID C.
Published: June 2012

Ventricular activation was studied in 20 patients with ischemic heart disease at the time of surgery for myocardial revascularization. Because most of the activation studies in man were limited to recording of epicardial potentials, a canine model of chronic infarction was also studied. Pre- and postinfarction data were recorded in dogs and correlated with the anatomy of the lesions. Epicardial Q waves, when associated with delayed epicardial activation, were diagnostic of underlying infarctions in areas of the heart that did not normally exhibit Q waves. In areas normally containing Q waves, underlying infarction was associated with Q waves greater in duration than the normal range determined for those areas of the epicardium. The experimental model of chronic infarction showed epicardial delay to be due to slowed intramyocardial activation rather than to delay in Purkinje conduction. Correlations between electrical and anatomic data in two patients suggested that, within limits, the detailed relationships between infarction and activation established with the canine model could be applied to human infarction to understand the genesis of the epicardial potentials and the ECG. The technique was also felt to have a practical clinical application in selection of areas of myocardium for vascular implants or infarctectomy.
Quantitative Hemodynamic Effects of Heart Rate in Aortic Regurgitation
Authors: JUDGE TERRANCE P. , KENNEDY J. W. , BENNETT LOWELL J. , WILLS ROBERT E. , MURRAY JOHN A. , BLACKMON JOHN R.
Published: June 2012

The hemodynamic effect of varying heart rate was studied in eight patients with aortic regurgitation. At the subjects' resting sinus rhythm and at a higher heart rate induced with right atrial pacing, left ventricular and aortic pressures and Fick cardiac outputs (FCO) were measured, and left ventricular biplane angiocardiograms were performed. Left ventricular volumes and left ventricular minute flow (LVMF) were determined from the angiograms. Regurgitant flow was quantitated by subtracting the FCO from LVMF. Increased heart rate produced highly significant reductions in the left ventricular end-diastolic pressure (LVEDP), left ventricular end-diastolic volume, and stroke volume. End-diastolic circumferential stress (EDCS) and end-diastolic load (EDL) were abnormally high at resting sinus rhythm and were markedly decreased with increased heart rate. FCO increased, but no significant changes were observed in either the LVMF or the regurgitant flow per minute.

Bradycardia in aortic regurgitation may cause pulmonary congestion secondary to high LVEDP and may accelerate left ventricular dilatation secondary to markedly elevated EDCS and EDL. The possible benefits of preventing bradycardia in aortic regurgitation by chronic demand pacing is currently being tested.
Midsystolic Clicks in Arteriosclerotic Heart Disease
Authors: STEELMAN R. BARRETT , WHITE RICHARD S. , HILL JOHN C. , NAGLE JOHN P. , CHEITLIN MELVIN D.
Published: June 2012

Midsystolic clicks (MSC), or nonejection systolic clicks, were discovered in 15 patients with arteriosclerotic heart disease (ASHD). The diagnosis of ASHD was established by the presence of angina or the history of a documented myocardial infarction (MI) or both. The MSCs were recorded in 13 patients. A late systolic murmur was introduced by the MSC in four patients, and one patient had a soft holosystolic murmur. The mitral origin of the MSCs and murmurs was established by noting their change in timing and intensity following administration of vasoactive drugs. One patient underwent cardiac catheterization, and evidence of an old MI and papillary muscle dysfunction (PMD) was demonstrated. We think that the PMD that occurs secondary to ischemic fibrosis in ASHD permits slack chordae tendineae suddenly to become taut in midsystole and produce a snap. Although the mechanism for the production of chordal snaps has been previously postulated, ASHD has only recently been found responsible for producing these sounds. The diagnosis of ASHD should be considered in patients with MSCs, even though they frequently occur in its absence.
Auscultatory Recognition of Aneurysm of the Membranous Ventricular Septum Associated with Small Ventricular Septal Defect
Authors: PIERONI DANIEL R. , BELL BARBARA B. , KROVETZ L. JEROME , VARGHESE P. JACOB , ROWE RICHARD D.
Published: June 2012

The clinical diagnosis of aneurysmal formation of the membranous ventricular septum associated with a small ventricular defect has been made previously only by means of angiocardiography.

Active movement of the aneurysm during cineangiocardiography suggested the possibility of a corresponding auscultatory event. When careful auscultatory and phonocardiographic examinations were performed on 21 patients previously documented as having a small membranous ventricular defect with an associated aneurysm, a distinct early systolic sound was heard in 17 (81%). This sound was "clicky" in quality, confined to a narrow area along the lower left sternal edge, and best heard in expiration. It occurred during the upstroke of the carotid arterial tracing and followed the Q wave by 100 to 130 msec.

On the basis of experience with other patients the development of this early systolic sound in a patient with a small ventricular septal defect suggests the diagnosis of associated septal aneurysm, but such a sequence requires confirmation by serial angiocardiography. Aneurysmal formation may be a prelude to spontaneous closure of the septal defect in which case auscultation of an early systolic sound should not only prove to be a valuable diagnostic sign for the clinician but may also be of considerable prognostic significance for the patient.
Prevalence of Plasma Lipoprotein Abnormalities in a Free-Living Population of the Central Valley, California
Authors: WOOD PETER D. S. , STERN MICHAEL P. , SILVERS ABRAHAM , REAVEN GERALD M. , VON DER GROEBEN JOBST
Published: June 2012

In an epidemiologic study of 1,118 free-living volunteers, aged 25 to 79 (552 male, 566 female) drawn from eight counties of the Central Valley, California, the following determinations were included: a medical history, blood pressure, resting electrocardiogram, plasma total cholesterol and glycerides (following a light, fat-free breakfast), and (when lipids were considered to be elevated) plasma lipoproteins determined by electrophoresis. A subgroup of the entire study population (494 male, 503 female) free of overt diabetes and electrocardiographic abnormalities, and with diastolic blood pressure not above 100 mm Hg, that was considered to be clinically "normal," forms the basis of this report.

Significant sex differences for mean levels of total cholesterol were absent or of small magnitude at all age decades up to and including the seventh. In contrast, glyceride levels for men were significantly higher than for women aged 25-59, and differences were substantial. Beyond the seventh decade, females had higher mean levels of both plasma total cholesterol and glycerides.

The type IV lipoprotein pattern was the most common abnormality (8.6%) within the entire normal population and was 2.7 times as common in men (13%) as in women (4.8%). Type II pattern was less common overall (3.7%) and was more frequent in women than in men. Types III (0.2 to 0.4%) and V (0.2%) were both very uncommon, and type I was not encountered. Results were similar when the entire population (normal and abnormal) was considered.

These findings suggest that sex differences in plasma total-cholesterol level cannot account for the known male preponderance in coronary heart disease within the population studied. Prolonged elevation of plasma glycerides (usually expressed as the type IV pattern) in males during the years when atherogenesis is occurring might account for the sex difference.
Cardiovascular Effects of Weight Reduction
Authors: ALEXANDER JAMES K. , PETERSON KIRK L.
Published: June 2012

Weight reduction programs usually improve the exercise capacity of patients with chronic exogenous obesity. However, the reversibility of left ventricular hypertrophy and dysfunction associated with obesity is unknown. Accordingly, an analysis was made of hemodynamic data obtained by cardiac catheterization and standard chest roentgenograms in nine markedly obese patients before and after weight loss of 39 to 84 kg (24 to 55% of control weight) over periods of 4 to 34 months. In each case body oxygen uptake (360 to 297 ml/min), blood volume (7.8 to 6.1 liters), cardiac output (7.9 to 6.2 liters/min), and arteriovenous oxygen difference (4.6 to 4.0 vol. %) were significantly reduced after weight loss. Systemic arterial pressure declined (102 to 87 mm Hg) while systemic vascular resistance changed insignificantly (1,067 to 1,141 dynes-sec-cm
-5
). In seven subjects comparable chest roentgenograms before and after weight reduction revealed decrease in the cardiothoracic ratio, suggesting a reduction in left ventricular dimensions. These results have been interpreted as indicating that the circulatory effects of gross obesity are largely reversible with weight loss. Despite reductions in left ventricular stroke work, stroke volume, and cavity size at rest, the average left ventricular filling pressure rose with exercise to a comparable and abnormal level (20 mm Hg) both before and after weight loss. Thus, evidence of left ventricular dysfunction persisted, suggesting that myocardial hypertrophy and reduced ventricular compliance did not regress significantly with weight loss over periods as long as 3 years.
Further Observations on the Ventricular Echo Phenomenon Elicited in the Human Heart
Authors: SCHUILENBURG REINIER M. , DURRER DIRK
Published: June 2012

In order to answer the question whether the atrium is a link in the pathway of ventricular reciprocation or whether the A-V node itself is the reflection point of the echo, a special stimulation program was followed in six patients in whom ventricular echo beats with stable time relations could be elicited by regular pacing of the right ventricle or by the application of appropriately timed right ventricular premature beats during regular pacing of the right ventricle. In these experiments the atrial septum was stimulated earlier than the expected arrival at the atrium of the retrograde impulse in the course of the echo sequence. The influence of stepwise (steps of 5 msec) advancing of this atrial "preexcitation" on the timing of the ventricular echo beat was studied.

We found that the atrial septum could be preexcited without interfering with the ventricular echo beat time relations over a time interval less than 5 msec in one patient, less than 10 msec in one, less than 20 msec in two, and less than 30 msec in two cases. When the time interval needed for the stimulated atrial impulse to reach the atrionodal margin is taken into account, it seems likely that the atrium participated in the echo pathway in the four cases with minimal atrial preexcitation intervals of 20 msec or less, and that in the two cases with a minimal atrial preexcitation interval of 30 msec the echo reflection point was localized in the upper part of the A-V node.
Serum Cortisol, Plasma Free Fatty Acids, and Urinary Catecholamines as Indicators of Complications in Acute Myocardial Infarction
Authors: PRAKASH RAVI , PARMLEY WILLIAM W. , HORVAT MATIJA , SWAN H. J. C.
Published: June 2012

Levels of serum cortisol, plasma free fatty acids (FFA), and urinary catecholamines were collected in 31 patients with acute myocardial infarction on the day of admission to the coronary care unit (samples obtained from 15 patients with diseases other than myocardial infarction were considered as controls). These values were correlated with the presence or subsequent development of left ventricular failure, arrhythmias, shock, or death. Sixteen of 17 infarction patients without the above complications had cortisol levels less than 20 µg%; 10 of 12 patients with complications had higher cortisol levels. All of the infarction patients without complications had plasma FFA levels less than 1100 µEq/liter, while six of nine patients with complications had levels of 1100 µEq/liter or higher. Fourteen of 16 patients without complications had urinary catecholamines less than 12.5 µg%, while seven of 10 patients with complications had levels greater than this. Of interest were a few patients without complications on admission, but with elevated cortisol or FFA levels, who developed complications on the following day. The results of the present study suggest that the generalized metabolic stress of acute myocardial infarction results in elevations of cortisol, FFA, and catecholamines as measurable biochemical indicators and/or predictors of the severity of the infarction.
Coronary Hemodynamics and Myocardial Oxygen Metabolism during Oxygen Breathing in Patients with and without Coronary Artery Disease
Authors: GANZ WILLIAM , DONOSO ROBERTO , MARCUS HAROLD , SWAN H. J.C.
Published: June 2012

Oxygen in high concentration (arterial pO
2
over 400 mm Hg), administered for 7-10 minutes to six subjects with normal coronary arteries and nine subjects with coronary artery disease caused the following significant changes: The heart rate and cardiac index decreased in both groups. The mean arterial pressure increased in the coronary group. The coronary sinus blood flow fell from 158 ± 11 (mean ±
sem
) to 131 ± 13 in the noncoronary and from 151 ± 14 to 138 ± 14 ml/min in the coronary group, due to an increase in coronary resistance. The coronary sinus oxygen tension increased from 19 ± 1 to 22 ± 1 in the noncoronary and from 19 ± 1 to 24 ± 1 mm Hg in the coronary group. The coronary arteriovenous oxygen difference decreased from 13.2 ± 0.6 to 12.5 ± 0.6 ml/100 ml in the coronary group. Left ventricular oxygen consumption fell from 21.5 ± 2.1 to 18.2 ± 2.4 in the noncoronary and from 19.9 ± 2.0 to 16.7 ± 1.7 ml/min in the coronary group. Myocardial lactate extraction increased from 40 ± 9 to 60 ± 4 and from 4 ± 6 to 28 ± 3%, respectively. In four patients with severe coronary artery disease, oxygen breathing reverted myocardial lactate production to extraction. It would appear that oxygen breathing might be beneficial in myocardial ischemia by increasing coronary arterial oxygen tension and reducing myocardial oxygen consumption.
Probability of Middle-Aged Men Developing Coronary Heart Disease in Five Years
Authors: KEYS ANCEL , ARAVANIS CHRIST , BLACKBURN HENRY , VAN BUCHEM F. S. P. , BUZINA RATKO , DJORDJEVIC B. S. , FIDANZA FLAMINIO , KARVONEN MARTTI J. , MENOTTI ALESSANDRO , PUDDU VITTORIO , TAYLOR HENRY L.
Published: June 2012

Characteristics of 11,132 men aged 40-59 years and free from coronary heart disease (CHD) at entry were related to follow-up experience, using multivariate analysis. In 5 years among 2,404 U. S. railroad men and 8,728 European men there were 615 cases of CHD, 214 of whom died from CHD or suffered definite nonfatal infarction.

With five entry characteristics (age, systolic blood pressure, serum cholesterol, smoking habit, and body mass index), multiple logistic solutions for Europeans and Americans, separately, gave estimates of the individual probability of CHD. Classified by deciled scores for these probabilities, the expected and observed CHD cases were highly correlated (r = 0.930-0.981). Predictions based on European data applied to Americans, and vice versa, gave similar high correlations but American incidence was excessive compared with European experience.

Application of the analysis coefficients obtained from data in Europe and in the U. S. railroad to 6,221 other U. S. men 40-59 years of age, CHD-free at entry, gave good prediction of
relative
risk (r = 0.94) for observed versus predicted cases in deciles of risk score; however, the actual numbers of cases were underpredicted.

From single measurements of a few characteristics the multiple logistic solution usefully estimates the relative risk of CHD for individuals. Age, systolic pressure, and serum cholesterol are universally powerful predictors of risk. Variables not measured in this study or not yet identified contribute to the risk of CHD among American men.
Some Reflections on the Coronary Bypass Operation
Authors: GLENN WILLIAM W. L.
Published: June 2012

A promising new operation-coronary bypass-has been developed for the treatment of coronary heart disease. However, because of the nature of the underlying disease and the minute size of the vessels to be anastomosed, its long-range prospects are in doubt. At this point in time there is no evidence that the operation either prevents infarction or prolongs life, and great caution is urged in applying it, reserving it for those who have life-threatening coronary artery disease, are clearly recalcitrant to optimum medical management, and have apparently normal coronary vessels distal to the point of stenosis.

There is an urgent need for a better definition of the indications for operation in patients with coronary artery disease based on a study of the natural history of this coindition. Prophylactic operation for patients with a compromised coronary circulation with or without angina must await long-term results of therapeutic operation.
Effect of Glucose-Insulin-Potassium Infusion on Myocardial Infarction following Experimental Coronary Artery Occlusion
Authors: MAROKO P. R. , LIBBY P. , SOBEL B. E. , BLOOR C. M. , SYBERS H. D. , SHELL W. E. , COVELL J. W. , BRAUNWALD E.
Published: June 2012

The effects of glucose-insulin-potassium (GIK) infusion and glucose (G) infusion started 30 min after experimental coronary occlusion and the combination of GIK and propranolol (P) started 3 hours after coronary occlusion on the development of myocardial infarction were studied in 37 dogs. Fifteen minutes after the coronary occlusion, epicardial electrocardiograms were recorded at 10-15 sites; 24 hours later transmural specimens were obtained from the same sites for determination of myocardial creatine phosphokinase (CPK) activity and the evaluation of morphologic changes. In the control group (normal saline infusion) the relationship between S-T-segment elevation (mv) 15 min after occlusion and CPK activity (IU/mg of protein) 24 hours later was: log CPK = –0.064 S-T + 1.24; r = 0.81. In the GIK group, the infusion was begun 15 min following epicardial mapping, and sites with the same S-T-segment elevations showed less CPK depression than did the control group: log CPK = –0.022 S-T + 1.25. The G group also showed less CPK depletion than the control group but to a somewhat lesser extent than the GIK group (log CPK = –0.030 S-T + 1.20). The group receiving GIK and P 3 hours after occlusion also showed less CPK depression than did the control group (log CPK = –0.034 S-T + 1.26). Histologic analysis in 24-hour specimens showed that sites which exhibited S-T-segment elevation 15 min after occlusion showed normal histology in 3% of specimens obtained from control dogs, while the other 97% showed early signs of myocardial infarction. However, in the GIK group, 36% of the specimens with S-T-segment elevation prior to the infusion were histologically normal 24 hours later, while in the G group 30% were normal, and in the GIK and P group 17% were normal. Electron microscopy confirmed the morphologic changes observed by light microscopy. Thus, in the presence of experimental coronary occlusion, GIK exerts a protective effect against myocardial ischemia and reduces the extent of myocardial necrosis. G alone acts similarly but to a lesser degree, while a beneficial effect can also be demonstrated when GIK and P are started 3 hours after the onset of coronary occlusion.
Ischemic Heart Disease
Authors: GERTLER MENARD M. , LEETMA HILLAR E. , SALUSTE ERICH , ROSENBERGER JAMES L. , GUTHRIE ROBERT G.
Published: June 2012

This study evaluates interrelationships between carbohydrate and lipid metabolism during oral glucose tolerance tests (GTT) in 65 ischemic heart disease (IHD) males and 69 age-matched healthy controls (age range 45 to 69 years). The frequency of abnormal GTT, usually accompanied by type IV hyperlipoproteinemia, was significantly higher in IHD (37%) than in controls (19%). The mean immunoreactive insulin (IRI) response curve of IHD patients with abnormal GTT showed an elevated and delayed peak at 2 hours. The mean free fatty acid response curve of IHD patients had a significantly lower rebound at 3 hours. IHD patients and controls with abnormal GTT showed significantly higher and lagging lactate levels at 2 and 3 hours. Incidence of abnormal GTT was neither related to relative weight nor to elapsed time from onset of IHD to time of examination. Canonical correlations revealed that IRI is the common denominator in both carbohydrate and lipid abnormalities in IHD.
Echocardiographic Pattern of Right Ventricular Diastolic Volume Overload in Children
Authors: TAJIK ABDUL J. , GAU GERALD T. , RITTER DONALD G. , SCHATTENBERG THOMAS T.
Published: June 2012

Echocardiograms were performed on 20 children who were 1-14 years old. Ten children had secundum atrial septal defects (ASD 2°); four had partial and two had complete atrioventricular canal defects (AVC); and three had partial and one had total anomalous pulmonary venous connection (APVC). Twenty-eight normal children were also examined. Echocardiograms of nine patients with ASD 2° revealed increased right ventricular dimension index (RVDI) and abnormal (paradoxic) ventricular septal (VS) motion. The remaining patient with ASD 2°, who had a Qp/Qs of 1.2 (smallest in the series), had a normal echocardiogram. All four patients with APVC had increased RVDI, and three had abnormal VS motion. The patient with normal septal motion had associated mild aortic stenosis, but he too had a small left-to-right shunt (19%). The echocardiograms of two patients with partial AVC revealed features similar to ASD 2°, but in the third patient who had significant mitral regurgitation (MR) the VS motion was normal, indicating that the degree of associated MR influences the VS motion in this anomaly. The septal motion was normal in both patients with complete AVC. Three patients in the series had abnormal systolic anterior motion of mitral valve. Postoperative echocardiograms revealed persistence of increased RVDI and "paradoxic" VS motion.
Relationship of Pulmonary Artery to Left Ventricular Diastolic Pressures in Acute Myocardial Infarction
Authors: RAHIMTOOLA SHAHBUDIN H. , LOEB HENRY S. , EHSANI ALI , SINNO M. ZIAD , CHUQUIMIA RUBEN , LAL ROSHAN , ROSEN KENNETH M. , GUNNAR ROLF M.
Published: June 2012

We have measured pulmonary artery (PA) and left ventricular diastolic pressures (LVDP) in patients with acute myocardial infarction to establish the relationships of PA pressure to LVDP. Paired determinations for the various parameters showed (mean difference in mm Hg): left ventricular end-diastolic pressure (LVEDP)-LVDP pre-a + 7.9,
P
< 0.001; LVEDP-mean PA wedge + 6.0,
P
< 0.001; mean PA wedge-LVDP pre-a, + 0.8,
P
> 0.2; PA end-diastolic pressure (PAEDP)-mean PA wedge (in all patients) +3.3,
P
< 0.001; PAEDP-mean PA wedge (patients with pulmonary vascular resistance ≦2 units) +1.3,
P
< 0.1; LVEDP-PAEDP +4.7,
P
< 0.001; and LVEDP-mean PA –2.0,
P
< 0.02. The relationship of LVEDP to mean PA wedge was: LVEDP (y) = 1.12 mean PA wedge (x) +4.69; Sy.x = 3.42; r = 0.92.

After acute myocardial infarction, PA pressures did not accurately reflect LVEDP because atrial contraction made a large contribution to ventricular filling pressure. In addition, PAEDPs were not the same as mean PA wedge pressures because of some increase of pulmonary vascular resistance in many patients. Thus, PA pressures only provided reliable information about the level of pulmonary venous pressure. LVDP pre-a correlated well with mean PA wedge pressure, and therefore measurement of LVDP (pre-a and EDP) yielded information not only about pulmonary edema, but also about LV performance.
Reduction by Hyaluronidase of Myocardial Necrosis following Coronary Artery Occlusion
Authors: MAROKO PETER R. , LIBBY PETER , BLOOR COLIN M. , SOBEL BURTON E. , BRAUNWALD EUGENE
Published: June 2012

Electrocardiographic, enzymatic, and morphologic signs of myocardial ischemic injury following coronary occlusion have previously been shown to be ameliorated by reducing myocardial oxygen requirements, and/or by increasing the availability of oxygen as well as of substrates for anaerobic ATP production. Since hyaluronidase increases diffusion through the extracellular space and may facilitate delivery of substrates to ischemic cells, the influence of its administration on the size of experimentally produced infarcts was studied. In 14 control dogs epicardial electrocardiograms were taken in 10-15 sites on the anterior surface of the left ventricle before and after occlusion of the left anterior descending coronary artery. Twenty-four hours later, transmural specimens were obtained from the same sites from which electrocardiograms had been recorded, and were analyzed for creatine phophokinase (CPK) activity, for histologic changes, and glycogen content. In control dogs, sites exhibiting S-T-segment elevation 15 min after occlusion showed early structural signs of necrosis and glycogen depletion in 97% of specimens taken after 24 hours. The relationship between S-T-segment elevation at 15 min (mv) and CPK activity 24 hours later (IU/mg protein) was log CPK = –0.061 S-T + 1.26. Hyaluronidase (225 u/kg) was given to 15 dogs; no hemodynamic changes occurred but the depression of CPK activity was reduced following occlusion; log CPK = –0.024 S-T + 1.28. Similarly, only 55% of sites that showed S-T-segment elevation prior to hyaluronidase administration exhibited histologic signs of early infarcts and glycogen depletion 24 hours later. It is concluded that hyaluronidase diminished myocardial necrosis following acute coronary occlusion.
Effects of Coronary Arteriography on Myocardial Blood Flow
Authors: KLOSTER FRANK E. , FRIESEN W. GLENN , GREEN GERALD S. , JUDKINS MELVIN P.
Published: June 2012

Myocardial blood flow responses to selective coronary arteriography were studied in 22 patients. Left coronary flow was estimated by the radioactive inert-gas (
133
xenon) washout technic using precordial detection. Duplicate control studies were obtained before radiocontrast injection and test studies were performed at 1 min and 3, 5, or 7 min after angiography. Eleven patients received a single 7-ml injection of methylglucamine diatrizoate and 11 were given a series of injections (average total 40 ml), with the test blood flow studies after the final injection.

Myocardial flow increased in every patient 1 min after contrast injection (average control flow 66.3 ml/min/100 g; test flow 78.8, +18.9%,
P
< 0.001). Blood flow increased further in seven of 10 studied at 3 min (average 95.7 ml/min/100 g, +35.7%,
P
< 0.001) and remained elevated at 5 and 7 min. Systemic pressure was unchanged from the control level, so coronary vascular resistance decreased in proportion to the increase in flow. Blood flow responses in patients with coronary artery disease were no different from normal subjects. Sham injections of normal saline produced no increase in coronary flow.

Selective coronary arteriography results in a prompt increase in myocardial blood flow which persists for several minutes. The probable mechanism is coronary vasodilatation produced by the markedly hypertonic contrast material, an effect demonstrated previously in other vascular beds.
Systolic Time Intervals as Measures of the Contractile State of the Left Ventricular Myocardium in Man
Authors: AHMED S. SULTAN , LEVINSON GILBERT E. , SCHWARTZ CARL J. , ETTINGER PHILIP O.
Published: June 2012

Previous studies relating systolic time intervals and measures of cardiac performance have suggested that the time intervals may be useful indices of myocardial contractility. To explore this possibility, systolic times and left ventricular (LV) performance and contractility were measured nearly simultaneously in 14 normal subjects and 56 patients with cardiac disease. Preejection period (PEP) and the ratio of PEP to LV ejection time (LVET) changed significantly with acute inotropic influences (exercise and isoproterenol), were normal in patients with right or left ventricular overloads in whom cardiac index and ejection fraction were depressed but contractile element velocity at peak dP/dt and the Frank-Levinson contractility index were normal, and were significantly abnormal in patients with either clinically evident or occult LV decompensation in whom the measures of contractility were reduced. Correlations of PEP and PEP/LVET with measures of both performance and contractility were insignificant for patients with valvular disease, shunts, or cor pulmonale and significant but weak for the entire series. However, in subjects with either normal left ventricles or cardiac disease confined to the left ventricle, PEP and PEP/LVET exhibited good correlations with measures of pump function and excellent correlations with measures of contractility. These results indicate that the systolic times are a valid measure of contractility which should prove useful in comparing patients with cardiac pathology confined to the LV myocardium and in following patients with extramyocardial hemodynamic lesions of constant severity.
Surgically Induced Right Bundle-Branch Block with Left Anterior Hemiblock
Authors: WOLFF GRACE S. , ROWLAND THOMAS W. , ELLISON R. CURTIS
Published: June 2012

A review of the electrocardiograms of 291 patients who survived more than 1 month after complete repair of tetralogy of Fallot disclosed that 24 (8.2%) developed a pattern of right bundle-branch block and left anterior hemiblock (RBBB-LAH) following surgery. When the course of these 24 patients was compared with a control group of 100 additional patients who did not develop this pattern following surgery, a significant increase in morbidity and mortality was noted.

Complete heart block developed at some time in the follow-up period in 41.7% of the RBBB-LAH group and in 4% of the control group. The incidence of serious ventricular arrhythmias was 16.7% for the RBBB-LAH group and 1% for the control group. Sudden death occurred in 12.5% of the patients with RBBB-LAH and in 2% of the controls. At the time of this review (1-12 years following surgery) overall late mortality was 25% for the RBBB-LAH group and 2% for the control group.

The study indicates that serious complications are much more frequent in tetralogy of Fallot patients who acquire the RBBB-LAH pattern during surgical repair. Prophylactic or therapeutic pacing may be indicated in many of these patients.
Echocardiographic Diagnosis of Idiopathic Hypertrophic Cardiomyopathy without Outflow Obstruction
Authors: ABBASI A S. , MACALPIN R. N. , EBER L. M. , PEARCE M. L.
Published: June 2012

The echocardiographic findings of eight patients with hypertrophic cardiomyopathy without outflow obstruction (HMC) and of 15 normal (Norm) individuals are presented.

The characteristic features in HMC were: (1) interventricular septal width much greater than normal (HMC = 2.5 ± 0.3 cm, Norm = 1.0 ± 0.2 cm,
P
< 0.005); (2) normal or only slightly increased posterior left ventricular wall thickness; (3) the ratio of interventricular septal to posterior wall thickness ≧2.0; (4) ejection fraction greater than normal (HMC = 0.76 ± 0.08, Norm = 0.68 ± 0.06,
P
< 0.025); (5) reduced velocity of the early diastolic closing motion of the anterior mitral leaflet (HMC = 60 ± 23 mm/sec, Norm = 124 ± 29 mm/sec,
P
< 0.005); (6) absence of abnormal systolic movement of the anterior mitral valve, as seen in hypertrophic obstructive cardiomyopathy. The diagnosis of hypertrophic cardiomyopathy can be made with echocardiography, even when outflow tract obstruction of the left ventricle is absent.
Coronary Artery Occlusion in the Conscious Dog
Authors: SMITH ELDON R. , REDWOOD DAVID R. , MCCARRON WILLIAM E. , EPSTEIN STEPHEN E.
Published: June 2012

Nitroglycerin is generally believed to be contraindicated during acute myocardial infarction because the resultant decrease in coronary perfusion pressure and reflex tachycardia might extend the area of ischemia. To determine the effects of nitroglycerin and alterations in arterial pressure on the degree of myocardial ischemia, the left anterior descending coronary artery was occluded for repeated 15-min periods in closed-chest conscious dogs. The degree of myocardial ischemia was estimated by summating the S-T segment elevation (∑ST) recorded from 12 myocardial electrodes. Although heart rate increased and arterial pressure decreased, ∑ST after 15 min of coronary occlusion was 14 ± 3 mv (
P
< 0.02) less during nitroglycerin therapy than during control occlusions. When the same alteration in arterial pressure was produced by venous hemorrhage, ∑ST tended to be greater than during control occlusions (+14 ± 7 mv,
ns
); the difference between the nitroglycerin and hemorrhage interventions was highly significant (28 ± 9 mv,
P
< 0.02). ∑ST was also less than control when phenylephrine was administered in doses sufficient to increase arterial pressure 25 mm Hg (–16 ± 3 mv,
P
< 0.005) and 50 mm Hg (–15 ± 2 mv,
P
< 0.001). When the decrease in arterial pressure and reflex tachycardia induced by nitroglycerin were reversed by simultaneous infusion of methoxamine, ∑ST was greatly reduced from control (–50 ± 16 mv,
P
< 0.02) and was significantly less than that occurring during nitroglycerin alone (–25 ± 5 mv,
P
< 0.001). We conclude that nitroglycerin may be a useful agent during acute myocardial infarction, particularly when the fall in coronary perfusion pressure and increase in heart rate are prevented by the simultaneous administration of an alpha-adrenergic agonist.
Inability of the Submaximal Treadmill Stress Test to Predict the Location of Coronary Disease
Authors: KAPLAN MARVIN A. , HARRIS CLIFFORD N. , ARONOW WILBERT S. , PARKER DAVID P. , ELLESTAD MYRVIN H.
Published: June 2012

Two hundred patients had submaximal treadmill stress tests (STSTs) and selective coronary arteriography performed within 2 months of each other. An attempt was made to assess the predictability of disease isolated to any given coronary vessel by performance on the treadmill. This was not possible for disease isolated to the right coronary, the left anterior descending, the circumflex branch of the left coronary, or a combination of right coronary and circumflex arteries. Eleven patients had disease in the left main coronary artery; all had associated disease of some other branch as well. One of these patients had a negative submaximal treadmill stress test but was unable to reach 90% of his maximum predicted heart rate. The remaining 10 patients had positive STSTs. Patients with 26-50% narrowing of any branch had treadmill results similar to those with 51-75% narrowing. There was a large number of patients with single-vessel disease in the study and most of the negative STSTs occurred in this group. Nevertheless, within this group no one vessel gave a higher incidence of positive STSTs than any other. It is concluded that (1) a positive STST is more likely to be associated with increased severity and extent of coronary artery disease; (2) a negative STST is more likely to be found in disease limited to a single vessel; and (3) within the latter group, the STST is of no value in predicting the specific coronary artery involved.
Progression of Coronary Artery Disease
Authors: BEMIS CHARLES E. , GORLIN RICHARD , KEMP HARVEY G. , HERMAN MICHAEL V.
Published: June 2012

Significant progression of coronary artery disease was seen in 52% of subjects studied by selective cinearteriography at intervals between 2 and 75 months (average 23.8). Subsequent progression, although confined to proximal areas, was independent of overall severity of initial disease or previous disease at the site of progression and occurred frequently in previously normal vessels. Plasma lipid abnormalities and myocardial lactate production at the time of the initial study were significantly associated with subsequent arteriographic progression. Similarly abnormal glucose tolerance was seen more frequently in patients exhibiting progression than in those who did not. The progression occurring in patients with lipid abnormalities was more severe and more widespread than in other patients, and apparent interval reduction in lipid values did not influence the ultimate course of the atheromatous process. Myocardial infarction was almost invariably associated with progression. Collateral coronary circulation never increased or appeared unless accompanied by an increase in the extent of local coronary artery disease. The absence of progression was associated with a favorable prognosis. All other clinical, laboratory, and arteriographic parameters analyzed were not predictive of subsequent progression of the coronary obstructive lesion.
Paradoxic Phenomenon of Premature Beats with Narrow QRS in the Presence of Bundle-Branch Block
Authors: MASSUMI RASHID A. , HILLIARD GENERAL , DEMARIA ANTHONY , FABREGAS RAMON , LINDSAY ALAN E. , AMSTERDAM EZRA , MASON DEAN T.
Published: June 2012

In contrast to the functional bundle-branch block (BBB) which is frequently rate-related and disappears when heart rate slows, we have encountered seven cases of a paradoxic disappearance of an existing, ischemia-induced BBB in premature beats. Supernormal conduction within the blocked bundle branch was not present in any of the cases. His bundle electrography in three of the cases demonstrated His spikes before each of the narrow-QRS premature beats. The His-Q intervals of the premature beats were considerably shorter than those of the control sinus beats. This finding clearly indicated an ectopic origin midway between the ventricular myocardium and the His bundle, i.e., within the ischemic fascicles of the left bundle, or the ischemic right bundle. From their points of origin such fascicular impulses propagate antegradely toward the respective area of the ventricular myocardium, and retrogradely toward the main His bundle, and at the same time down the remaining two fascicles. The antegrade conduction time in the short pathway down the ischemic fascicle is equaled by the faster conduction through the longer pathways of the remaining, uninjured fascicles, thereby accounting for the almost simultaneous activation of the myocardium of the two ventricles and the resultant narrow-QRS complexes.
Quantitative Assessment of Left Ventricular Diastolic Stiffness in Man
Authors: GROSSMAN WILLIAM , STEFADOUROS MILTIADIS A. , MCLAURIN LAMBERT P. , ROLETT ELLIS L. , YOUNG DANIEL T.
Published: June 2012

An approach to the quantitative assessment of left ventricular (LV) diastolic stiffness in man has been developed utilizing strip-chart recordings of simultaneous ultrasonic LV dimensions, LV pressure, and electrocardiogram (ECG). In 23 patients without regional abnormalities of contraction, LV pressure, and LV internal diameter (D = distance between endocardial surfaces of LV posterior wall and septum at the plane of the mitral valve) were determined at the onset (P
1
, D
1
) and peak (P
2
, D
2
) of left atrial mechanical systole. In addition, left ventricular volumes, V
1
and V
2
, were calculated from D
1
and D
2
using a regression formula for end-diastolic volume previously determined from biplane angiographic studies. This allowed calculation of ΔP/ΔD and ΔP/ΔV associated with the "a" wave of the LV pressure trace, and these ratios were utilized as measures of LV stiffness late in diastole.

Patients with LV hypertrophy by standard ECG criteria had much greater late diastolic stiffness (11 patients, ΔP/ΔD = 6.1 ± 1.1 mm Hg/mm, ΔP/ΔV = 1.0 ± 0.2 mm Hg/cc) than those without LV hypertrophy (12 patients, ΔP/ΔD = 1.8 ± 0.2 mm Hg/mm, ΔP/ΔV = 0.29 ± 0.04 mm Hg/cc,
P
< 0.001 for each ratio).

Comparison of the stiffness ratios showed significant variation among patients with different disease states. Thus, late diastolic stiffness was highest in patients with aortic stenosis (three patients, ΔP/ΔD = 8.9 ± 2.9 mm Hg/mm, ΔP/ΔV = 1.5 ± 0.5 mm Hg/cc), lowest in mitral stenosis (four patients, ΔP/ΔD = 1.5 ± 0.5 mm Hg/mm, ΔP/ΔV = 0.23 ± 0.06 mm Hg/cc), and intermediate in patients with aortic regurgitation (three patients, ΔP/ΔD = 4.8 ± 0.7 mm Hg/mm, ΔP/ΔV = 0.83 ± 0.12 mm Hg/cc) and mitral regurgitation (three patients, ΔP/ΔD = 3.2 ± 0.7 mm Hg/mm, ΔP/ΔV = 0.5 ± 0.1 mm Hg/cc).

It is concluded that the quantitative evaluation of LV diastolic stiffness obtained by this approach correlates well with the presence or absence of LV hypertrophy and with the underlying pathophysiology.