bluuebunny/crossref_metadata_2025 huggingface dataset:
Cord-like aortic valve vegetation in bacterial endocarditis. Demonstration by cardiac ultrasonography. Report of a case.
Authors: Yoshikawa J , Tanaka K , Owaki T , Kato H
Published: June 2012

The ultrasonic features in a case of bacterial endocarditis in which a highly mobile, cord-like vegetation, attached to the noncoronary cusp of the aortic valve, are reported. The echocardiogram demonstrated abnormal echo patterns in the left ventricular outflow tract in diastrole which were continuous with similar echoes in the aortic root. While these findings did not differ from the previously reported manifestations in cases of flailing aortic valve leaflets, the cardiac ultrasonogram distinguished this vegetative growth. Cardiac ultrasonography revealed a cord-like characteristic, showed the movement of the entire growth into the left ventricular outflow tract in diastole and into the aorta in systole, and allowed estimation of the size of the vegetation. We conclude that cardiac ultrasonography can help in differentiating aortic valve leaflet flail and vegetations in endocarditis.
The conducting tissues in primitive ventricular hearts without an outlet chamber.
Authors: Wilkinson J L , Anderson R H , Arnold R , Hamilton D I , Smith A
Published: June 2012

We have studied the disposition of the cardiac conducting tissues in four hearts from situs solitus individuals possessing primitive ventricles without outlet chambers. These hearts correspond to the type of univentricular heart defined as common ventricle by Lev. All the hearts studied possessed normally positioned great arteries. Two groups, each consisting of two hearts, could be distinguished. The first type possessed a small posterior ridge which divided the posterior portion of the primitive ventricle into right and left ventricular sinuses. The papillary muscles to the atrioventricular valves were separate structures and arose on each side of this posterior ridge. The conducting tissues in these hearts arose from an atrioventricular node situated in the atrial septum but deviated posteriorly. The atrioventricular bundle pierced the fibrous annulus posteriorly and descended on the posterior ridge, lying to its left side. A bifurcation was not identified, and bundle branches were not present. The other two hearts had no posterior ridge. A common posterior papillary muscle supported both atrioventricular valves, and in one a marked anterior muscle bar produced obstruction of the pulmonary outflow tract. The connecting atrioventricular node was situated laterally in the right atrioventricular valve orifice, and the atrioventricular bundle descended into the right parietal wall of the primitive ventricle. A bifurcation and bundle branches were not observed. The disposition of conducting tissue in these hearts differs from that found in "primitive ventricle with outlet chamber" in that the connecting atrioventricular node and bundle are situated anteriorly and are intimately related to the transposed pulmonary artery outflow tract in the latter anomaly. The surgical significance of these findings is emphasized.
Cellular protection during myocardial ischemia: the development and characterization of a procedure for the induction of reversible ischemic arrest.
Authors: Hearse D J , Stewart D A , Braimbridge M V
Published: June 2012

An isolated perfused working rat heart model was used to investigate the extent to which various protective agents, used either singly or in combination, were able to increase the resistance of the heart to periods of transient ischemia. The aim of the studies was to develop a solution which, if infused into the coronary vessels just prior to the onset of ischemia, would rapidly induce arrest and would also counteract several of the deleterious cellular changes known to occur during myocardial ischemia. Agents with induce cardiac arrest, modify cellular ion loss, affect substrate utilization, energy production and energy stores, affect coronary vessel diameter and cell swelling, prevent dysrhythmias, and affect metabolic rate were investigated. The additive effects of these agents were evaluated. An aqueous solution was formulated which contained high concentrations of potassium and magnesium, in combination with adenosine triphosphate, creatine phosphate and procaine. This solution increased the recovery of the ischemic (37 degrees C for 30 min) rat heart from 0% to 93%. The safe period of ischemia could be further increased by the use of hypothermia.
Abolition of ischemic response to atrial pacing following aortocoronary bypass surgery.
Authors: Jugdutt B I , Lee S J , Taylor R F
Published: June 2012

To determine the effect of successful aortocoronary bypass surgery (ACBS) on left ventricular (LV) function, the ischemic response to right atrial pacing (RAP) was studied in 22 angina patients before and 3.8 +/- 1.1 months after surgery. All patients were free of angina after ACBS and had at least one patent graft. Before ACBS, RAP induced angina in 15 patients (Group 1) but not in 7 patients (Group 2). After ACBS, no patient had angina with RAP despite the increased maximum rate of pacing. Post-pacing LV end-diastolic pressure (LVEDP) after ACBS decreased in Group 1 from 25 +/- 6 to 15 +/- 6 mm Hg (P less than 0.01), but not in Group 2. Changes in ejection fraction, cardiac output, resting LVEDP, or LVEDP after LV angiography were not significant in either group and were therefore not useful in evaluating the result of ACBS. However the ischemic response to right atrial pacing was abolished by successful aortocoronary bypass surgery, suggesting improved myocardial perfusion during stress.
Studies of blood pressures in children, ages 5-14 years, in a total biracial community: the Bogalusa Heart Study.
Authors: Voors A W , Foster T A , Frerichs R R , Webber L S , Berenson G S
Published: June 2012

Blood pressure, height, weight, maturation, triceps skinfold thickness, serum lipids, and hemoglobin were measured as risk factors for coronary artery disease in 3,524 children (93% of the eligible population) in Bogalusa, Louisiana. Nine blood pressures were taken on each child by trained observers with mercury sphygmomanometers (Baumanometer) and Physiometrics automatic recorders in a rigid randomized design in a relaxed atmosphere with other children present. The pressures observed were low compared to reported data. Black children had significantly higher blood pressures than white children. This difference, starting before age 10, was largest in the children in the upper five percent of the pressure ranks. Stepwise multiple regression analysis revealed that this racial differnce was significant when measured by an automatic recorder. Body size, expressed by height and by weight/height3 index, was a strong determinant of blood pressure level. Other positive determinants were blood hemoglobin and external maturation.
Single film retrograde umbilical aortography in the diagnosis of hypoplastic left heart syndrome with aortic atresia.
Authors: Rosengart R , Jarmakani J M , Emmanouilides G C
Published: June 2012

Single film retrograde umbilical aortography was used successfully in confirming the diagnosis of hypoplastic left heart in three neonates. The method involves injecting Renografin 75% (1.25 cc/kg body weight) into the umbilical artery catheter according to the following sequence. First, the tip of the catheter is positioned at the level of the ductus arteriosus. The infant heart beats are then counted from one to three. The contrast media injection is begun manually on the count of one and an anterior-posterior chest film is taken on the count of three. Thus the film is taken one diastolic period after completion of the injection. The proper timing of the contrast media injection and filming is essential for obtaining a diagnostic film. This procedure was diagnostic in the three infants studied and eliminated the need of transferring two sick infants from affiliated hospitals.
Multiple accessory pathways in patients with the pre-excitation syndrome.
Authors: Gallagher J J , Sealy W C , Kasell J , Wallace A G
Published: June 2012

We have studied 135 patients with the pre-excitation syndrome and have demonstrated evidence of multiple accessory pathways in 20 patients. Five patients had two distinct accessory atrioventricular (A-V) connections, associated with enhanced A-V node conduction in one patient. Twelve patients had a single accessory A-V connection associated with enhanced A-V conduction. In one of these there was an additional fasciculo-ventricular connection. One patient had an accessory A-V connection associated with a nodoventricular bundle. Two patients had fasciculo-ventricular connections combined with enhanced A-V conduction. The latter two patients had electrocardiograms suggestive of a complete accessory A-V connection. Patients with enhanced A-V conduction had shorter cycle lengths during reciprocating tachycardia, primarily because of a short A-H during the dysrhythmia, than those without such conduction. In addition, patients with enhanced A-V conduction demonstrated more rapid conduction from atrium to His bundle during induced atrial fibrillation and two developed life-threatening ventricular responses during atrial fibrillation. A nodo-ventricular pathway was documented to participate in reciprocating tachycardia in one patient. Surgery was undertaken in 13 patients. In 11, the intraoperative mapping studies confirmed the preoperative predictions. In two patients, the presence of a second accessory A-V connection was documented after ablation of one.
Use of changes in the epicardial QRS complex to assess interventions which modify the extent of myocardial necrosis following coronary artery occlusion.
Authors: Hillis L D , Askenazi J , Braunwald E , Radvany P , Muller J E , Fishbein M C , Maroko P R
Published: June 2012

The goal of this study was to determine if changes in the epicardial QRS complex after coronary artery occlusion (CAO) can be used to evaluate the efficacy of interventions designed to limit infarct size. Forty-one open-chest dogs with CAO were studied: 15 were controls, 18 received hyaluronidase and eight received propranolol starting 20 minutes after CAO. Epicardial ECGs were recorded at specific time intervals to analyze ST-segment elevation and changes in Q and R waves. Transmural specimens were obtained 24 hours after CAO from the same sites at which ECGs were recorded. Q wave development (deltaQ), R wave fall (deltaR), and their combination (deltaR + deltaQ) at 24 hours correlated with the extent of necrosis, as determined by myocardial creatine phosphokinase activity depression and histologic appearance. In the control group ST-segment elevation 15 minutes after CAO (ST15M) predicted changes in Q and R waves 24 hours later; in the treated groups, the same ST15M prior to drug administration resulted in significantly less QRS changes. Thus, 1) Q wave development and R wave fall 24 hours after CAO accurately reflect myocardial necrosis. 2) ST15M predicts subsequent changes in Q and R waves. 3) The efficacy of hyaluronidase and propranolol, agents previously shown to reduce myocardial necrosis, can be detected by less Q wave development and a smaller fall in R wave voltage.
De subitaneis mortibus. XX. Cardiac electrical instability in the presence of a left superior vena cava.
Authors: James T N , Marshall T K , Edwards J E
Published: June 2012

Abnormalities of cardiac rhythm have been reported by others in patients with a persistent left superior vena cava. We present the histological findings from postmortem examination of the cardiac conduction system of two such patients. The first patient was a schoolboy who died suddenly and unexpectedly. His sinus node was abnormally small, his A-V node contained numerous venous lacunae and was stretched out beneath the enlarged coronary sinus, both A-V node and His bundle were dispersed in the central fibrous body in a fetal pattern, and isolated fragments of A-V nodal tissue were connected to the myocardium at the crest of the interventricular septum. The second patient complained of palpitations many months prior to surgical correction of an interventricular septal defect; his postoperative course included multiple arrhythmias and he died suddenly on the 16th postoperative day. Although his sinus node was histologically normal, the nutrient artery contained a polypoid fibromuscular mass virtually occluding its lumen; his A-V node and His bundle were also dispersed in the central fibrous body in the fetal pattern, and the A-V node contained numerous venous lacunae as well as being histologically disorganized in its cytological pattern. These anatomical findings may indicate a basis for various forms of cardiac electrical instability, and deserve consideration in the future evaluation of any patient found to have a persistent left superior vene cava, but particularly if there is clinical evidence suggesting an arrhythmia or conduction disturbance.
The hemodynamic effects of induced supraventricular tachycardia in man.
Authors: Goldreyer B N , Kastor J A , Kershbaum K L
Published: June 2012

The circulatory effects of supraventricular tachycardia (SVT) were studied in eight patients who reported disabling symptoms during paroxysms of the arrhythmia. Supraventricular tachycardia was induced in each patient by rapid atrial pacing or with atrial premature stimuli. Hemodynamic parameters in sinus rhythm and following the initiation of SVT were recorded and compared. The following mean values were observed in sinus rhythm (SR) and SVT. Heart rate (beats/min): SR 79, SVT 183; P-R interval (msec): during SR, 154; during SVT, 256; ratio of mean P-R intervals to mean R-R cycl lengths: SR 20%, SVT 76%; brachial artery pressures (mmHg): SR 141, SVT 99; cardiac index (L/min/m2): SR 3.6, SVT 2.2; pulmonary artery pressures (mmHg): SR 18/7, SVT 26/15; peak right atrial pressures (mm Hg): SR 4, SVT 17. Large waves appeared in the right atrium during SVT due to atrial contraction against closed tricuspid valves. Pulsus alternans were observed in each case during SVT. Despite the presence of chest pain during SVT, the coronary arteries were normally patent in four patients who underwent coronary arteriography.
Two-dimensional echocardiographic assessment of mitral stenosis.
Authors: Nichol P M , Gilbert B W , Kisslo J A
Published: June 2012

A real-time, phased-array, two-dimensional echocardiography system was used to assess mitral valve motion in 30 catheterized patients with pure mitral stenosis. Suitable images for analysis of mitral valve motion were obtained in 25 patients. The valve leaflets were most thickened and immobile at the leaflet tips while maximum mobility was at the leaflet body. Diastolic movement of anterior mitral leaflet toward the septum pulled the posterior mitral leaflet mid-portion inferiorly. Systolic bulging of the mid-portion of the anterior mitral leaflet into the left atrium was seen in 40% (10 of 25). Movement of the anterior mitral leaflet in diastole is primarily due to movement of the whole mitral apparatus in patients with mitral stenosis. The anterior mitral leaflet E to F slopes did not correlate (r=0.38) with the mitral valve area determined at catheterization. Planimetry of the mitral valve area directly from the videotape images compared favorably to the valve area determined at catheterization (r=0.95). Thus, mitral valve area determined by this technique is an accurate noninvasive method for assessing the severity of mitral stenosis.¿
Palliation of cyanotic congenital heart disease in infancy with E-type prostaglandins.
Authors: Neutze J M , Starling M B , Elliott R B , Barratt-Boyes B G
Published: June 2012

Prostaglandin-E (PGE) infusions have been used in an attempt to increase ductal patency in 11 infants aged one to 99 days with cyanotic heart disease. PGE1 was used in nine infants and PGE2 in two. Five patients had pulmonary atresia, four extreme pulmonary stenosis, one Ebstein's anomaly and one simple transposition of the great arteries. All but the oldest infant showed a satisfactory increase in oxygen saturation (average 36%) attributed to dilatation of the ductus. The failure in one infant may have been due largely to hypoplasia of the left pulmonary artery. The only important side effect was apnea in one infant receiving PGE2. The efficacy of this form of treatment is confirmed in infants dependent on ductal patency for survival. PGE is an important asset in saving the lives of neonates requiring an aorticopulmonary shunt operation. The recommended starting dose is 0.1 mug/kg/min of PGE1 given by constant infusion.
Comparison of echocardiographic and necropsy measurements of ventricular wall thicknesses in patients with and without disproportionate septal thickening.
Authors: Maron B J , Henry W L , Roberts W C , Epstein S E
Published: June 2012

In several patients with asymmetric septal hypertrophy (ASH) diagnosed by echocardiography (septal-free wall thickness ratios greater than or equal to 1.3), we have discovered marked discrepancies between the echocardiographic and necropsy measurements of wall thicknesses that led to uncertainty regarding the actual cardiac diagnosis. To resolve these apparent incongruities, the echocardiograms and hearts of 17 patients with cardiac disease were studied. Six of nine patients with abnormal septal-free wall ratios greater than or equal to 1.3 during life had septal-free wall ratios that were not diagnostic of disproportionate septal thickening at necropsy. Such discrepancies may be explained as follows: 1) echocardiographic measurements during life were made in diastole (as per convention), but measurements at necropsy were made in hearts that appeared to have been in the systolic phase of the cardiac cycle; 2) the left ventricular free wall thickens considerably more than the ventricular septum in systole, as determined by echocardiography. This latter phenomenon resulted in septal-free wall ratios in systole that were consistently smaller than those in diastole. Furthermore, septal-free wall ratios obtained at necropsy corresponded most closely to those obtained by echocardiography in systole.
Cardiac function in total anomalous pulmonary venous return before and after surgery.
Authors: Mathew R , Thilenius O G , Replogle R L , Arcilla R A
Published: June 2012

Cardiac performance was evaluated in 12 infants with isolated total anomalous pulmonary venous return. Four had significant pulmonary venous obstruction and severe pulmonary hypertension (group A). Eight had no obvious venous obstruction, and the pulmonary pressures were lower (group B). In all subjects, right ventricular end-diastolic volume was increased (197% of predicted normal) and its ejection fraction was normal. Left ventricular volume was, generally speaking, still in the normal range (87% of predicted normal); however, its ejection fraction was reduced (0.57 vs normal of 0.73) and left ventricular output was low (3.08 L/min/m2 vs normal of 3.98). Left atrial volume was consistently small (53% of predicted normal) with an appendage of normal size. The infants in group A had smaller chamber volumes/m2 BSA than those in group B. Left atrial function was abnormal, characterized by reduced reservoir function and a greater role as "conduit" from right atrium to left ventricle. Left atrial size was not found to be critical in the surgical repair of TAPVR. Cardiac function is restored to normal following surgery.
Coronary arterial origin in persistent truncus arteriosus.
Authors: Shrivastava S , Edwards J E
Published: June 2012

Specimens of heart from 30 subjects with persistent truncus arteriosus were studied for the nature and sites of coronary arterial origin. These factors were related to the sinuses of the truncus valve. Bicuspid truncal valve was observed in six cases (20%) and tricuspid in 21 cases (70%). Single coronary artery was observed in four cases (three with tricuspid and one with quadricuspid truncal valves). In three other cases the coronary arteries arose separately but near one another. There was a strong tendency for the left coronary artery to arise from a more posterior level than it does normally from the aorta. It was common for the posterior descending artery to arise from the left circumflex artery. This arrangement was noted in eight of 25 cases (32%) with single posterior descending coronary artery. In five other cases, two posterior descending arteries were present, one arising from the left circumflex and the other from the right coronary artery.
The effect of the Valsalva maneuver on echocardiographic dimensions in man.
Authors: Robertson D , Stevens R M , Friesinger G C , Oates J A
Published: June 2012

Physiologic changes in the circulatory system caused by performing the Valsalva maneuver are blunted or absent in patients with congestive heart failure. Previously there has been no noninvasive method for examining cardiac chamber size during this maneuver. M-mode echocardiography was used to evaluate possible changes in cardiac chamber dimensions in 12 normal subjects (group I) and 15 patients with cardiovascular disease (group II). In group I, the left ventricular end-diastolic dimension decreased 11.2% (+/- 1.5%) and the end-systolic dimension 9.5% (+/- 1.32%), with a fall in stroke volume of 29%. The left atrial (LA) dimension decreased 30%. In group II, only the response of the LA dimension is reported. There was a diminished response to Valsalva related to the severity of congestive heart failure. Patients in NYHA classes III and IV decreased LA dimension by only 3.8%, significantly less (P less than 0.001) than those in classes I and II who had essentially normal responses. Echocardiographically-determined changes in left atrial size in response to the Valsalva maneuver may provide an objective, noninvasive means of evaluating and following patients with suspected or proven congestive heart failure. Possible mechanisms for the changes observed are discussed.
Platelet survival time in patients with hypoxemia and pulmonary hypertension.
Authors: Steele P , Ellis J H , Weily H S , Genton E
Published: June 2012

Platelet survival time (autologous labeling with 51chromium) was measured in 63 patients in order to evaluate the role of platelets in the thromboembolic complications of patients with hypoxemia and pulmonary hypertension. Thirty-eight of these patients had chronic obstructive airways disease; 13, primary pulmonary hypertension; seven, recurrent pulmonary embolism; four, the Eisenmenger syndrome; and one, multiple pulmonary arteriovenous fistula. Forty-three patients were hypeakly associated with arterial oxygen tension ( r = 0.50), but not with the arterial carbon dioxide tension or the level of pulmonary artery pressure. Sulfinpyrazone lengthened platelet survival in 12 of 24 (50%) treated patients but this drug did not alter either arterial oxygen tension arterial carbon dioxide tension, or pulmonary artery pressure. Our results suggest that hypoxemia is associated with shortened platelet survival time and that platelets may, therefore, be involved in the thromboembolic complications that develop in patients with hypoxemia.
Correlation of mean pulmonary artery wedge pressure, left atrial dimention, and PTF-V1 in patients with acute myocardial infarction.
Authors: Orlando J , Del Vicario M , Aronow W S , Cassidy J
Published: June 2012

The mean pulmonary artery wedge pressure (PAWP), left atrial dimension (LAD) by echocardiography, and PTF-V1 in the electrocardiogram were correlated with each other in 16 patients with acute myocardial infarction in the control period and after therapeutic intervention with either Dextran or furosemide and/or nitroprusside. No significant correlation was found between a normal control PAWP and the LAD. An increased control PAWP correlated well with an increased LAD (r = 0.98). No significant correlation was found between the LAD and the PAWP whether normal or elevated after therapeutic intervention. No significant correlation was found between the PAWP whether normal or elevated and the PTF-V1. No significant correlation was found between the LAD and the PTF-V1. We conclude in acute myocardial infarction 1) the PTF-V1 is not useful in assessing PAWP before or after therapeutic intervention, 2) the LAD correlates poorly with a normal control PAWP but correlates well with an elevated control PAWP, and 3) the LAD cannot be used to assess PAWP after therapeutic intervention.
Baroreflex sensitivity in patients with Takayasu's aortitis.
Authors: Takeshita A , Tanaka S , Orita Y , Kanaide H , Nakamura M
Published: June 2012

Takayasu's aortitis is an arterial inflammatory disease of arteries of unknown etiology. Fainting is a common symptom and has been attributed to ypersensitivity of the baroreflex. We studied baroreflex sensitivity in 11 patients with Takayasu's aortitis and compared it with that of eight control subjects of comparable age. Baroreflex sensitivity was assessed by determining the slope of a regression line relating the rise of systolic arterial pressure to the prolongation of the R-R interval of the electrocardiogram during a transient rise of arterial pressure induced by an intravenous injection of phenylephrine. The average baroreflex slope of patients with Takayasu's arteritis (4.0 +/- 0.8 msec/mm Hg) was significantly less than that of control subjects (10.7 +/- 0.8 msec/mm Hg, P less than 0.001). Reduced baroreflex sensitivity in patients with Takayasu's aortitis may be due to the hardening of the arteries where baroreceptors lie, or to hypertension and/or cardiac disease which was present in most of the patients included in this study. Patients with Takayasu's aortitis who complained of fainting also showed the reduced baroreflex sensitivity. This indicates that fainting in this disease is not likely to be caused by the hyperreactivity of the baroreceptors as is commonly postulated.
Detection of remote myocardial infarction in patients with positron emission transaxial tomography and intravenous 11C-palmitate.
Authors: Sobel B E , Weiss E S , Welch M J , Siegel B A , Ter-Pogossian M M
Published: June 2012

Ischemic myocardial injury has been detected recently in isolated perfused hearts and intact experimental animals with positron-emitting 11C-palmitate and reconstructive tomography providing cross-sectional images of the heart free from superimposed activity in overlying structures. To evaluate the applicability of positron emission transaxial tomography in detecting infarction in man, 10 normal human subjects and 12 patients who sustained documented acute myocardial infarction three to 12 months previously were studied. Tomograms were obtained after intravenous injection of 5 to 10 mCi of 11C-labeled palmitate, a physiological substrate of myocardium. Tomograms from all normal subjects exhibited homogeneous distribution of 11C-palmitate throughout each 1.5 cm thick cross section of the ventricle. Tomograms from all patients with remote anterior or inferior and posterior myocardial infarction exhibited diminished accumulation of 11C-palmitate delineating regions corresponding to the electrocardiographic locus of infarction. The distribution of 11C-palmitate detectable by positron emission transaxial tomography in a series of cross sections from apex to base in the same normal subject or patient with remote myocardial infarction was analogous to that observed in normal dogs and animals with experimentally induced myocardial infarction.
Combined dopamine and nitroprusside therapy in congestive heart failure. Greater augmentation of cardiac performance by addition of inotropic stimulation to afterload reduction.
Authors: Miller R R , Awan N A , Joye J A , Maxwell K S , DeMaria A N , Amsterdam E A , Mason D T
Published: June 2012

The hemodynamic benefits of combining administration of dopamine with nitroprusside (NP) were evaluated in nine patients with chronic congestive heart failure due to ischemic, idiopathic myocardial or valvular cardiac disease. NP alone (68 microng/min) produced decline in left ventricular end-diastolic pressure (LVEDP) from 25.4 to 14.1 mm Hg (p less than 0.01) but modest increase in cardiac index (CI) from 2.41 to 3.02 L/min/m2 (P less than 0.05). Dopamine alone (6 microng/kg/min) caused an elevation of CI to 3.36 (P less than 0.01) but without decrease of LVEDP. Simultaneous infusion of the two agents resulted in favorable alterations in both hemodynamic variables: LVEDP decreased to 15.7 (P less than 0.01) and CI increased to 3.52 (P less than 0.01). It is concluded that dopamine substantially enhances the effectiveness of nitroprusside therapy in congestive heart failure by providing concomitantly the principal beneficial actions of the vasodilator and dopamine used separately. Thus combined dopamine with NP treatment considerably raises low CI while markedly reducing elevated LVEDP and provides a potentially efficacious pharmacologic modality for the treatment of severe congestive heart failure due to left ventricular dysfunction.
Pulmonary vascular disease complicating the Blalock-Taussig anastomosis.
Authors: Hofschire P J , Rosenquist G C , Ruckerman R N , Moller J H , Edwards J E
Published: June 2012

The pulmonary vascular bed was evaluated following a Blalock-Taussig shunt performed in 36 patients for decreased pulmonary blood flow. The time of follow-up ranged from one to 21 years after operation. No patients developed severe pulmonary changes in less than eight years after institution of the shunt. Ten of 20 patients having a shunt eight years or longer developed some degree of pulmonary vascular disease, mainly in the form of intimal fibrosis. This was severe in six of the 20 patients. As the duration of the shunt increased, so did the incidence of pulmonary vascular disease.
Myocardial imaging with thallium-201 at rest and during exercise. Comparison with coronary arteriography and resting and stress electrocardiography.
Authors: Ritchie J L , Trobaugh G B , Hamilton G W , Gould K L , Narahara K A , Murray J A , Williams D L
Published: June 2012

Myocardial imaging with intravenous thallium-201 (201Tl) was performed at rest and following maximal treadmill exercise in 101 patients with suspected coronary artery disease. Results were interpreted from Polaroid scintiphotos by three independent observers with complete interobserver agreement in 79%. Of 25 patients with no or insignificant coronary artery disease (less than 50% diameter stenosis), one (4%) had a resting 201Tl image defect, one (4%) had an exercise 201Tl defect, none had an ECG Q wave, and four (16%) had exercise ST-segment depression. Among 76 patients with coronary artery disease (greater than or equal to 50% diameter stenosis), 58 (76%) had a defect on either the rest or exercise 201Tl image. The proportion of patients with an exercise image defect (50/76, 66%) was greater than the proportion with exercise ST depression alone (34/76, 45%; P less than 0.02). Overall, 69 of the 76 (91%) patients with coronary artery disease had either a positive rest or exercise myocardial image and/or a positive rest (ECG Q waves) or exercise (ST depression) electrocardiogram. This exceeded the proportion with only rest or exercise electrocardiographic abnormalities (50/76, 65%; P less than 0.001). We conclude that rest and exercise myocardial imaging with 201Tl is easily accomplished with readily available imaging equipment. The image data enhanced the diagnostic sensitivity of stress electrocardiography, and provided spatial identification of the abnormal segment(s) of myocardium.
Echocardiographic assessment of a normal adult aging population.
Authors: Gerstenblith G , Frederiksen J , Yin F C , Fortuin N J , Lakatta E G , Weisfeldt M L
Published: June 2012

Echocardiograms were performed on 105 male participants in the National Institutes on Aging's volunteer Longitudinal Study Program. All subjects (25--84 years of age) were physically active and had no evidence of hypertension or cardiovascular disease. Measurements were made of the initial diastolic (E-F) slope of the anterior mitral valve leaflet, the aortic and left ventricular cavity dimensions, and the thickness of the posterior left ventricular wall. Fractional shortening of the minor semi-axis of the left ventricle and the velocity of circumferential fiber shortening were also determined. It was found that increasing age correlated with a decrease mitral valve E-F slope and increased aortic root diameter and left ventricular wall thickness. Aging did not affect left ventricular cavity dimension, fractional shortening of the minor semi-axis, and velocity of circumferential fiber shortening. These findings suggest that aging in the normal male is associated with altered left ventricular diastolic filling, increased aortic root diameter and left ventricle hypertrophy but little change in contractile ability in the resting state.
Serum glycoproteins in coronary artery disease.
Authors: Snyder S , Coodley E L , Durham B C , Pennock R S
Published: June 2012

Serum glycoprotein levels were compared in two groups of age- and sex-matched patients, 15 with coronary artery disease and 14 normal controls. While total glycoprotein levels were increased in the coronary group, significantly higher levels were found in only five of 16 glycoproteins--C3c haptoglobin, GC-globulin, alpha1-acid glycoprotein, and C3 activator--with no change in 10 other glycoproteins and significant decrease in transferrin. This study demonstrates what appears to be a glycoprotein profile in coronary artery disease and reviews possible interactions of glycoproteins with known risk factors in atherogenesis.
Arteriographic evidence of coronary arterial spasm in acute myocardial infarction.
Authors: Oliva P B , Breckinridge J C
Published: June 2012

Coronary arteriography was performed before and after the intracoronary injection of nitroglycerin to determine the presence or absence of spasm in patients within the first 12 hours of acute myocardial infarction. Coronary arterial spasm was demonstrated in six of fifteen (40%) acute myocardial infarctions associated with coronary artery disease. In five of the six instances the interval from the onset of symptoms to arteriography was less than 6 hours. Spasm was superimposed on a high-grade atherosclerotic obstruction and was separated from the catheter tip by a segment of normal vessel in each instance. The coronary artery remained patent (following the initial relief of spasm) in two patients maintained on sublingual nitrates and heparin. Spasm, superimposed on an atherosclerotic obstruction, may be the primary event or a secondary occurrence in the pathophysiology of acute myocardial infarction. Catecholamines could play an important role in the early pathophysiology of acute myocardial infarction by producing spasm and/or platelet aggregation at the site of an atherosclerotic obstruction. A dynamic interaction between spasm, platelet aggregates and the atherosclerotic plaque may precede coronary thrombosis.
Comparative hemodynamic effects of inotropic and vasodilator drugs in severe heart failure.
Authors: Mikulic E , Cohn J N , Franciosa J A
Published: June 2012

In 12 patients with severe congestive heart failure (CHF) due to ischemic heart disease or nonischemic cardiomyopathy the hemodynamic response to intravenous infusion of sodium nitroprusside (N) was compared to that of dobutamine (D) 10 microgram/kg/min. D and N produced comparable increases in cardiac output (CO) (2.8 to 5.8 L/min and 2.9 to 5.0 L/min, respectively), but, compared to N, D caused a higher arterial pressure (99.3 vs 86.2 mm Hg, P less than 0.01) and heart rate (102.5 vs 95.3, P less than 0.05) and less reduction in pulmonary wedge pressure (PWP) (28.9 to 20.2 mm Hg vs 29.1 to 16.6 mm Hg, P less than 0.05). In five additional patients N and D were studied separately and then were infused together. The combination resulted in a higher CO, lower PWP and greater reduction in systemic and pulmonary vascular resistances than either drug alone. Brachial arterial infusion of nitroprusside produced prominent forearm vasodilation in a dose less than 10% of the systemic dose, whereas vasodilation with dobutamine was only modest even when 50% of the systemic dose was infused. Therefore, potent inotropic and vasodilator drugs produce similar and additive augmentation to left ventricular performance in heart failure. Reduction in vascular resistance with dobutamine probably is largely of reflex origin, but the vasodilation itself may be an important determinant of the rise in cardiac output.
Prediction of the normal blood volume. Relation of blood volume to body habitus.
Authors: Feldschuh J , Enson Y
Published: June 2012

Predictions of blood volume (BV) assume the existence of a constant ratio between BV and body weight or surface area (SA). We examined the validity of this assumption by calculating BV from plasma volume and body hematocrit in 160 normal volunteers whose weights ranged from -38.7 to 210.8% of desirable weight (assessed by a modification of the Metropolitan Life Insurance Company Desirable Weight tables). BV is not a constant fraction of body weight or SA in this population. Its prediction from such constant ratios results in a large error of estimate which is systematically biased with respect to height and weight. BV prediction from the observed regressions of the parameter on weight and SA reduces the error substantially but remains biased with respect to height. BV prediction from the subject's degree of deviation from desirable weight affords a smaller error of estimate which is apparently free from systematic bias.
Right and left heart size and function in infants with symptomatic coarctation.
Authors: Graham T P , Atwood G F , Boerth R C , Boucek R J , Smith C W
Published: June 2012

Right and left heart volumes, ejection fractions and ventricular outputs were determined from biplane cineangiocardiograms in infants with symptomatic coarctation of the aorta and correlated with clinical and hemodynamic alterations. Patients were divided into two age groups: group 1, aged 3.5 to 14 days and group 2, 5 weeks to 7 1/2 months. Infants in group 1 had severe depressions of left ventricular ejection fraction and output associated with normal left ventricular size. The massive cardiomegaly in these infants results from right heart enlargement secondary to left-to-right atrial shunting, and pulmonary hypertensive right heart failure, and possibly a more distensible right than left ventricle. Infants in group 2 also have right, and to a lesser degree, left heart enlargement. Group 2 patients differ from group 1 infants in having less impairment of left heart pump function and significant left ventricular myocardial hypertrophy. Echocardiographic measurements of left ventricular pump function are normal or increased in postoperative patients. Thus alterations of left ventricular function in infants with symptomatic coarctation appear to be largely afterload related and do not indicate permanent impairment of left ventricular contractile function.
De subitaneis mortibus. XXVI. Fatal electrical instabiltiy of the heart associated with benign congenital polycystic tumor of the atrioventricular node.
Authors: James T N , Galakhov I
Published: June 2012

Benign congenital polycystic tumors of the atrioventricular (A-V) node are an unusual but not very rare cause of heart block. Two such cases are presented and discussed in conjunction with the reported experience of other. The tumor is always within and only very near the A-V node, seldom involves more than the proximal end of the His bundle, and has not been reported to occur in the sinus node. Although sudden death has been reported in conjunction with these tumors, a surprising number of other patients have lived to old age and died of causes unrelated to the A-V nodal tumor. As a corollary it is important to consider a diagnosis of A-V nodal tumor in any patient of any age who presents with otherwise unexplained heart block or syncope. From accumulated experience it appears that such patients do not tolerate electronic pacing safely and some possible explanations for this are discussed. Escape rhythm in all reported cases has been characterized by QRS complexes which are narrow and a ventricular rate which is from half to two-thirds of the sinus rate. Reasons why an A-V junctional rhythm which is 66% of sinus rate may be especially stable are discussed.
Cross-sectional echocardiographic visualization of the stenotic pulmonary valve.
Authors: Weyman A E , Hurwitz R A , Girod D A , Dillon J C , Feigenbaum H , Green D
Published: June 2012

Real-time, cross-sectional echocardiograms of the pulmonary valve were recorded in 22 patients with valvular pulmonary stenosis (VPS) (14 mild, eight moderate or severe) and 25 normal subjects. Normally during systole the pulmonary leaflet echoes moved rapidly apart and in the fully opened position lay parallel and in close apposition to the margins of the pulmonary artery. In 20 of 22 patients with VPS in whom the pulmonary valve was recorded the systolic configuration of the leaflets, opening pattern of the leaflet echoes, and presence of presystolic doming served to differentiate the stenotic valve from normal. In contrast M-mode recordings of the pulmonary valve were possible in only 12 of these 22 cases (seven mild and five moderate or severe) and suggested VPS in only the five cases with moderate or severe stenosis. Cross-sectional echocardiography offers a direct, noninvasive method for visualizing the stenotic pulmonary valve and should be improvement over the indirect M-mode data.
The wavefront phenomenon of ischemic cell death. 1. Myocardial infarct size vs duration of coronary occlusion in dogs.
Authors: Reimer K A , Lowe J E , Rasmussen M M , Jennings R B
Published: June 2012

Irreversible ischemic myocardial cell injury developes in an increasing number of cells as the duration of coronary occlusion is prolonged. The present study quantitates myocardial necrosis produced by 40 minutes, 3 hours, or 6 hours of temporary circumflex coronary occlusion (CO) followed by 2 to 4 days of reperfusion, or by 24 or 96 hours of permanent circumflex ligation in pentobarbital anesthetized open chest dogs. After 40 minutes of ischemia, myocyte necrosis was subendocardial but with increasing duration of coronary occlusion, irreversible injury progressed as a wavefront toward the subepicardium. Transmural necrosis was 38 +/- 4% after 40 min, 57 +/- 7% after 3 hours, 71 +/- 7% after 6 hours and 85 +/- 2% after 24 hours of ischemic injury. These results document the presence of a subepicardial zone of ischemic but viable myocardium which is available for pharmacologic or surgical salvage for at least three and perhaps six hours following circumflex occlusion in the dog.
Effects of sublingual nitroglycerin on resting pulmonary gas exchange and hemodynamics in man.
Authors: Mookherjee S , Fuleihan D , Warner R A , Vardan S , Obeid A I
Published: June 2012

Simultaneous hemodynamic, ventilation and blood gas measurements were performed in 19 males during cardiac catheterization for evaluation of chest pain syndrome before and 3 to 5 min after 0.4 mg sublingual nitroglycerin. Pulmonary arterial pressures and total pulmonary vascular resistance fell (P less than 0.001 for both), and mean systemic arterial pressure decreased (P less than 0.05). However, peripheral vascular resistance, cardiac output, and mixed venous PO2 did not change. Total and tidal ventilation, PCO2, pH, and base excess remained unchanged. However, the arterial PO2 decreased from a mean of 80 +/- 3 (SEM) to 72 +/- 2 mm Hg (P less than 0.001) and mean venous admixture increased from 8.8 +/- 1% to 12.6 +/- 1.5% (P less than 0.001). The alveolar arterial PO2 difference increased (P less than 0.001) and the dead space tidal volume ratio rose (P less than 0.05). We conclude that the decrease in arterial PO2 following sublingual nitroglycerin is caused by redistribution of pulmonary blood flow with imbalance in ventilation-perfusion relationships or shunting.
Paroxysmal supraventricular tachycardia in patients with mitral valve prolapse.
Authors: Josephson M E , Horowitz L N , Kastor J A
Published: June 2012

The mechanism of supraventricular tachycardia was evaluated in twelve patients with mitral valve prolapse utilizing standard intracardiac recording and stimulation techniques. Eight patients had normal electrocardiograms, three had a short PR interval and normal QRS (Lown-Ganong-Levine syndrome) and one had Wolff-Parkinson-White type A. Six of the eight patients with normal electrocardiograms were demonstrated to have atrioventricular bypass tracts. Five patients had A-V nodal re-entrant supraventricular tachycardia. In two patients the bypass tract could be demonstrated to conduct antegradely when the left atrium was paced via the coronary sinus, while in four the bypass tract only conducted retrogradely. In all seven patients with atrioventricular bypass tracts, the accessory pathway was left-sided. We conclude that a) supraventricular tachycardia in the mitral valve prolapse syndrome appears related to a high frequency of bypass tracts; b) electrophysiological studies are required to diagnose these bypass tracts; and c) the atrioventricular bypass tracts may be related to the mitral valve abnormality since they are always left-sided.
Comparison of effects of nitroprusside and prazosin on left ventricular function and the peripheral circulation in chronic refractory congestive heart failure.
Authors: Awan N A , Miller R R , Mason D T
Published: June 2012

We compared cardiocirculatory actions of nitroprusside (NP) to prazosin (PZ) in eleven chronic coronary patients with refractory congestive heart failure. Each drug equally lowered systemic arterial pressures mildly while heart rate was unaltered. NP decline (P less than .001) in left ventricular filling pressure (28 to 17 mm Hg) and rise (P less than .005) in cardiac index (2.20 to 2.96 L/min/m2) were similar to PZ (30 to 17) and (2.08 to 3.00). PZ and NP equally enhanced cardiac efficiency of stroke work and myocardial oxygen consumption index. Total systemic vascular resistance declined (P less than .001) the same with NP and PZ. Forearm vascular resistance (FVR) and venous tone (FVT) diminished equally with NP and PZ. Similar FVR/FVT percent changes of 0.88 and 0.64 with NP and PZ indicated relatively balanced systemic arteriovenous relaxation. Sinze PZ effects persisted six hours with symptomatic improvement, oral PZ is the best vasodilator for long-term use, extending in-hospital NP-like actions to ambulatory heart failure therapy.
The absent pulmonary valve syndrome. Considerations of management.
Authors: Pinsky W W , Nihill M R , Mullins C E , Harrison G , McNamara D G
Published: June 2012

The absent pulmonary valve syndrome consists of a severely hypoplastic pulmonary valve with anular stenosis, aneurysmal dilatation of the main pulmonary artery with one or both pulmonary branches also dilated, and a ventricular septal defect. From 1955 to 1975, 15 patients were seen at Texas Children's Hospital with this syndrome. Although anatomically similar to tetralogy of Fallot, the most significant symptoms during early infancy were secondary to bronchial compression resulting from the dilated pulmonary arteries and enlarged left atrium. Intracardiac repair performed on two infants at four months of age failed to ameliorate the respiratory symptoms and both died. Seven patients from 2.3 to 16 years of age were operated upon, with one late postoperative death. Five other patients have not yet received surgical intervention. We recommend vigorous continual respiratory therapy for for infants and small children and intracardiac repair in older children since repair in infancy does not relieve respiratory symptoms. We do not recommend a prosthetic pulmonary valve unless there is persistently elevated main pulmonary artery pressure.