bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantification of myocardial ischemia and infarction with 201thallium scintigraphy
Authors: Nelson A. D. , Leighton R. F. , Andrews L. T. , Khullar S. C. , Ross J. N. , Budd G. C. , Gohara A. 
Published: February 2009

AbstractA quantitative method for the analysis of 201thallium myocardial scintigrams, developed in an experimental infarcted dog heart model, has been compared with two nonquantitative methods for interpretation of stress myocardial scintigrams in two groups of patients studied with coronary angiography: 11 with normal coronary arteries and 14 with coronary artery disease. Three independent observers interpreted scintigrams which were 1) not computer processed; 2) corrected for background activity in lungs and chest wall; and 3) processed by a computer method which uses a uniform threshold of counts determined from the dog model to define perfusion defects. Interobserver variability as well as sensitivity and specificity of detecting coronary disease were examined.In patients with coronary artery disease interobserver variability was improved by using the computer technique: observers agreed as to the existence of a perfusion defect in 93% of the scintigrams as compared to 55% and 81% for the unprocessed and background‐subtracted images respectively. No false positive indications of coronary disease were obtained by any of the three techniques. Use of the computer method did not improve the sensitivity of detecting coronary disease, however—71% compared to 64% for unprocessed images and 79% for background‐subtracted images. The advantages of this quantitative computer method are increased consistency of interpretation and lack of false positive diagnoses of coronary disease. An improved sensitivity of detection may be gained by varying thallium count thresholds according to anatomic location in the heart.
Ventricular septal rupture detected by cross‐sectional echocardiography
Authors: Dabrowski R. C. , Troup P. J. , Olinger G. N. , Wann L. S. 
Published: February 2009

AbstractCross‐sectional echocardiography was used to directly visualize abnormal wall motion and detect the site of ventricular septal rupture in a patient with acute inferior myocardial infarction. The presence of the defect was confirmed by injecting indocyanine green into the left ventricle at the time of cardiac catheterization. Cross‐sectional echocardiography provides a rapid, atraumatic means for evaluating patients with complicated acute myocardial infarction.
The use of propranolol and nifedipine in the medical management of angina pectoris
Authors: Fox K. M. , Jonathan A. , Selwyn A. P. 
Published: February 2009

AbstractThis study investigates the use of propranolol and nifedipine in the treatment of angina pectoris. The clinical response and the effects on the precordial 16‐lead electrocardiogram before and after exercise were studied in 52 patients with frequent angina pectoris. Relief of chest pain and abolition of exercise‐induced ST‐segment depression was achieved in 16 patients on treatment with propranolol alone (mean dose, 300 mg/d). Of the remaining 36 patients, the precordial area and severity of exercise‐induced ST‐segment depression were unchanged in 8 patients, of whom 2 reported they were free from chest pain, improved in 10 patients of whom 4 reported they were free of chest pain, and abolished in 14 patients, all of whom were free from chest pain following treatment with both propranolol and nifedipine (mean dose, 50 mg/d). Four patients were unable to tolerate this combination.This study has shown that in patients who do not respond to treatment with propranolol alone the combination of propranolol and nifedipine can be used to control not only anginal pain, but also the precordial electrocardiographic manifestations of ischemia.
Coronary artery disease confined to secondary branches of the left coronary system
Authors: Iskandrian A. S. , Klein B. L. , Segal B. L. , Kimbiris D. , Bemis C. E. 
Published: February 2009

AbstractAmong 3,000 patients studied by coronary arteriography during a 4‐year period, 31 patients (1%) had coronary artery disease limited to a diagonal branch of the left anterior descending (15 patients), marginal branch of the left circumflex (10 patients), or to both branches (6 patients). Ten patients had 50‐69% and twenty‐one had ⩾70% diameter narrowing. The suitability for grafting was noted in 20 patients as judged by the caliber and distribution of the diseased branches. Collaterals were noted in seven patients. Disease was present in 28 men and 3 women (age range 38‐70 years). At least one major coronary risk factor was present in 27 patients. Angina was noted in 27 patients; prior myocardial infarction was noted in 5 patients by history and in 4 by ECG. The left ventriculogram was normal in 22 patients and showed mild segmental asynergy in 9; ejection fraction was normal in all. Exercise ECGs were positive in 12 of 25 patients; exercise201 thallium scans were positive in 13. All patients responded to medical therapy.
Predictors of ventricular fibrillation or cardiac arrest in patients hospitalized for acute myocardial infarction
Authors: Tonascia J. , Szklo M. , Goldberg R. , Kennedy H. 
Published: February 2009

AbstractA community‐wide study of patients hospitalized with acute myocardial infarction in metropolitan Baltimore was conducted to examine socio‐demographic and clinical characteristics in association with ventricular fibrillation and cardiac arrest (VF/CA). Multivariate analyses revealed that variables significantly associated with occurrence of VF/CA included older age (60 years or older), male sex, and a history of cigarette smoking. These factors allow the identification of subgroups of patients hospitalized with acute myocardial infarction at high risk for the subsequent development of VF/CA, in whom prophylactic therapy and close surveillance are especially recommended.
Facial Swelling: A Complication of Transvenous Pacing
Authors: Deanfield J. E. , Fox K. M. , Allison D. J. 
Published: February 2009

AbstractSummary: A case of progressive venous thrombosis involving the superior vena cava is reported following implantation of a permanent transvenous pacemaker. Acute symptoms in the arm appeared after 18 months, but the symptoms of superior vena caval obstruction developed gradually, three years after pacemaker insertion. The diagnosis was confirmed by cavography and symptoms resolved with heparin therapy. Long‐term anticoagulation is indicated when thrombosis is responsible for this uncommon but important complication of transvenous pacing.
Hemodynamics before and after physical endurance training in patients with myocardial infarction under various physical and psychomotor stress tests
Authors: Buchwalsky R. 
Published: February 2009

AbstractSummary: This hemodynamic study was done in 23 post myocardial infarction patients. The peripheral and central hemodynamics were examined by repeated er‐gometer tests, heart volume estimations, and heart catheterizations under various provocative techniques such as dynamic bicycle ergometer load, static hand grip load, volume load, atrial pacing, and psychomotor stress. After a 5‐week period of endurance training we found a marked and statistically significant increase (40%) of maximal work tolerance and a significant decrease (10%) in heart rate and atrial blood pressure at rest and on equal levels of work load. No significant influence was seen on central (pulmonary) pressure readings at rest or on equal levels of work load beside the higher venous oxygen extraction. These peripheral effects of physical training were seen for all provocative tests, and also for those which were not trained as static and volume load and psychomotor stress.
Invasive and Noninvasive Assessment of Pulmonic Regurgitation: Clinical, angiographic, phonocardiographic, echocardiographic, and doppler ultrasound correlations
Authors: Chandraratna P. A. N. , Wilson D. , Imaizumi T. , Ritter W. S. , Aronow W. S. 
Published: February 2009

AbstractSummary: Three patients with pulmonic regurgitation and no evidence of pulmonary hypertension were investigated. These patients had low pitched diastolic murmurs which increased on inspiration, evidence of connective tissue disease as manifested by lax joints and hyperextensible skin, and marked hilar dance which extended up to the peripheral vessels. Suprasternal echocardiography revealed dilatation and increased systolic expansion of the right pulmonary artery (RPA) (25% and 28%, respectively) in two patients; the third patient had a normal RPA dimension in diastole and a marked increase in diameter (88%) in systole. Thus, these three patients demonstrated hyperdistensibility of the RPA. The spectral signal from the pulsed Doppler echocardiograph showed evidence of turbulent blood flow in diastole (wide dispersion of the dots) in the right ventricular outflow tract in all three patients. This pattern was indicative of pulmonic regurgitation. In summary, the combined use of echocardiography and Doppler ultrasound is useful in the evaluation of patients with pulmonic regurgitation.
Beta‐Blocker Therapy Evaluated by Radionuclide Angiography: A study in chronic stable angina
Authors: Lessem J. 
Published: February 2009

AbstractSummary: In order to evaluate the negative inotropic effects of sotalol, metoprolol, and propranolol in patients with chronic stable angina pectoris, left ventricular ejection fraction (LVEF) was measured with radionuclide angiography and echocardiography. Fifteen patients entered the study, which was designed as a randomized crossover trial. The patients served as their own control at all times. Surprisingly, LVEF increased when measured by echocardiography in all three treatment periods, and decreased in the propranolol period when measured by radionuclide methods. The changes were not significant. There was no negative inotropic effect registered during any of the three drug treatments.
Aberrant origin of the left coronary artery from the proximal right coronary artery: Diagnostic features and pre‐ and postoperative course
Authors: Liberthson R. R. , Zaman L. , Weyman A. , Kiger R. , Dinsmore R. E. , Leinbach R. C. , Strauss H. W. , Buckley M. J. 
Published: February 2009

AbstractSummary: In this report, we present the pre and late postoperative course of a patient with severe angina secondary to aberrant origin or the left coronary artery from the proximal right coronary artery (Fig. 1). We illustrate the noninvasive diagnosis and evaluation of this patient by two‐dimensional ultrasound and stress thallium imaging, and the pre and late postoperative angi‐ographic and thallium perfusion findings.
Verapamil in effort‐induced angina pectoris in patients with normal coronary arteries
Authors: Hasin Y. , Rod J. L. , Lewis B. S. , Gotsman M. S. 
Published: February 2009

AbstractSummary: Two patients with classical effort‐induced angina pectoris associated with abnormal ST‐segment depression on graded exercise testing and normal coronary arteriograms are described. Both patients deteriorated during treatment with propranolol, and became asymptomatic during treatment with verapamil with normal graded exercise tests. Verapamil may thus improve an inadequate vasodilatatory response of the coronary vascular bed to effort.
Methacholine provocation of prinzmetal's variant angina pectoris: A revised perspective
Authors: Stang J. M. , Kolibash A. J. , Bush C. A. , Schorling J. B. 
Published: February 2009

AbstractWe report 13 patients with unequivocal Prinzmetal's variant angina pectoris as the entire experience with this syndrome during a 7‐year period in a single institution. The clinical diagnosis of this relatively uncommon disorder is emphasized. Five patients were given 10 mg of methacholine subcutaneously. Three demonstrated subsequent delayed appearance of chest pain, ECG change, and coronary vasospasm following early appearance of muscarinic effects. Two Prinzmetal patients had no provocation of variant angina following methacholine, though they did experience significantly less blood pressure fall in response to muscarinic provocation. Another 23 subjects with incompletely explained chest pain given methacholine had neither ECG change nor spasm. Methacholine provocation of variant angina need not necessarily implicate a parasympathomimetic mechanism for otherwise spontaneous episodes. Rather, provocation would appear to occur via the customary reflex adrenergic response to drug‐induced hypotension. Methacholine is probably safe though unreliable as an agent to be used for spasm provocation.
Oxygen consumption in adult patients during cardiac catheterization
Authors: Dehmer G. J. , Firth B. G. , Hillis L. D. 
Published: February 2009

AbstractThe determination of cardiac output by the Fick principle requires the quantitation of the arterio‐venous oxygen (O2) content difference across the pulmonary bed and the O2 consumption. Since a correct measurement of O2 consumption may be difficult, an assumed value is sometimes substituted into this equation. Despite this practice, there is no appropriate reference standard for O2 consumption applicable to the adult catheterization laboratory. Therefore, we determined O2 consumption in 108 patients (69 men and 39 women, mean age, 49 years) at the time of catheterization by multiplying the arteriovenous O2 content difference by the indicator dilution cardiac output, thereby eliminating errors related to the collection and analysis of a timed collection of expired air. O2 consumption index (O2 consumption/m2 of body surface area) averaged 126 ± 26 ml/min/m2 (mean±SD), but there was wide variability (65–250 ml/min/m2). O2 consumption was not affected by patient age or sex but was lower in those who were mildly sedated before catheterization (sedated, 121±22 ml/min/m2; nonsedated, 132±28 ml/min/m2; p = 0.023). Thus, O2 consumption varies greatly among adults at the time of cardiac catheterization, so that any attempt at estimating this variable is fraught with major potential error.
Influence of ipratropiumbromide on heart rate and hemodynamics in patients with sinus bradycardia
Authors: Kikis D. , Esser H. , Heinrch K. 
Published: February 2009

AbstractIn 13 patients with sinus bradycardia, heart rate and hemodynamics were recorded before and 3, 30, 60, and 120 minutes following intravenous administration of 0.5 mg ipratropiumbromide (Itrop® by C. H. Boehringer Sohn, Ingelheim, West Germany). Heart rate already started to rise during the injection of ipratropiumbromide. It increased by an average of 78% three minutes following the administration as compared to pretreatment control values. Mean heart rate still was markedly increased by an average of 26% at 120 min following the injection of the drug. This effect of ipratropiumbromide on heart rate was accompanied by an increase in cardiac index while stroke volume decreased due to a decrease in ejection fraction and diastolic filling time.
Absence of secular changes in the prognosis of patients with an initial myocardial infarction
Authors: Goldberg R. J. , Kennedy H. L. , Gore J. M. 
Published: February 2009

AbstractA community‐based study was conducted in metropolitan Baltimore in which secular trends in the in‐hospital and long‐term prognosis of 935 male and female patients hospitalized with an initial myocardial infarction were examined for the two periods of 1966–1967 and 1971. The in‐hospital case fatality rate among males in both periods remained unchanged (19.0% vs 19.0%), whereas there was a decrease over time among women hospitalized in 1966–1967 as compared to those in 1971 (37.2% vs 26.6%) (p<0.10). For patients discharged alive from the hospital and followed up for as long as 10 years, no significant differences in overall survival were observed between male patients discharged in 1966–1967 and 1971 or between female patients discharged in these two periods. These findings may reflect the lack of major therapeutic advances in the care of the acute coronary patient between the two study periods and, therefore, support continuing efforts directed at the primary and secondary prevention of the atherosclerotic process.
Correlations of hemodynamic parameters with plasma catecholamines in patients with congestive cardiomyopathy
Authors: Lehmann M. , Wybitul K. , Kapp R. , Spielberger B. , Keul J. 
Published: February 2009

AbstractNoradrenaline and adrenaline blood levels, as well as central hemodynamics (Swan‐Ganz semi‐floating balloon‐tipped catheter), were measured at rest and during moderate exercise in 8 male patients suffering with idiopathic congestive cardiomyopathy (COCM), and in 12 healthy male control subjects. The stroke volume and the cardiac output in COCM were, on the average, one‐half that of the control subjects; adrenaline, noradrenaline, pulmonary capillary wedge pressure, as well as the roentgenographically determined heart volume (at rest) in COCM were, on the average, increased more than twice the control values. The noradrenaline and adrenaline responses in COCM reached at the 25‐W exercise level the response of controls at the 150‐W level. Direct correlations were observed between the cate‐cholamine responses and the capillary wedge pressure as well as the heart volume; inverse correlations existed between the catecholamines and the stroke volume or the cardiac output. The results may be indicative of a causal relationship between the reduced function of the left heart and a compensatorily increased sympathetic activity, but they are not at all conclusive for a definite cause‐effect response. The differences in catecholamine levels and the correlations are more significant for noradrenaline during both exercise and rest, whereas for adrenaline significance only occurred during exercise. The noradrenaline and adrenaline levels may serve as indicators (especially in the chronic stage) in the diagnosis of reduced left ventricular function.
Interactions between a rapid atrial stimulator and a multiprogrammable ventricular demand pacemaker
Authors: Berman N. D. 
Published: February 2009

AbstractA patient with drug‐resistant supraventricular tachycardia was well controlled for 8 years with a patient‐activated rapid atrial pacemaker until she developed symptomatic bradycardic episodes. A multiprogrammable ventricular pacemaker was implanted. Assessment of the interactions between the two pacemakers demonstrated inhibition of VVI pacing by the atrial stimulator initially. Two months after implant no interaction was seen. At no time was VVT pacing affected by the atrial stimulator. Thus, interactions between these two units can occur and a multiprogrammable pacemaker should be used in this situation as it offers the flexibility to minimize any interaction that might be present.
Accuracy of various techniques in the measurement of the duration of the q wave: A possible source of error in diagnosing myocardial infarction by electrocardiography
Authors: Mazzoleni A. , Demaria A. N. 
Published: February 2009

AbstractThe method of measuring the width of the Q wave on electrocardiogram is one of the variables contributing to conflicting findings regarding the accuracy of the ECG in the diagnosis of myocardial infarction. This study assesses the accuracy of a variety of methods of measuring the width of the Q wave recorded by direct‐writing electrocardiographic instruments. The assessment was made by comparing the width of the Q wave as inscribed by thermal direct‐writing electrocardiographs to the width of the Q wave as measured from an oscilloscopic display, the latter representing the “true” width of the Q wave. The measurement of the width as obtained from the upper edge of the tracing obtained with direct‐writing electrocardiographs underestimated the true width of the Q wave, while the opposite was the case by measuring the width along the lower edge of the tracing. The most reliable ways to obtain the true width of the Q wave are: (1) to average the measurements as obtained along the upper and lower edge, (2) to measure the width along an ideal line in the middle of the tracing, or (3) to measure the width along the trailing edge of the deflection.
Proximal left anterior descending coronary heart disease and complex ventricular arrhythmias
Authors: Koenig W. , Schinz A. , Hofmann H. 
Published: February 2009

AbstractIn this study, 87 consecutive patients with angiographically proven coronary artery disease (CAD, stenosis >75%) underwent 24‐h Holter monitoring, 76 of them having had transmural myocardial infarction, a mean of five months before evaluation. Of the total, 51 patients showed single‐vessel disease, in 31 (61%) of them with involvement of the left anterior descending (LAD) artery. In 26 patients with proximal LAD stenosis or occlusion and usually large aneurysms and subsequently impaired left ventricular function relatively low prevalence of significant ventricular premature contraction (VPC, Lown (III) was seen. On the contrary in 19 patients with multivessel disease and proximal LAD stenosis advanced forms of VPCs were present in 63% (p<0.01). Further both groups differed significantly in the frequency of postinfarction angina (30% vs. 100%; p<0.001) and their incidence in positive exercise stress tests (15% vs. 84%; p<0.001). Ejection fractions were comparable in both groups (mean 45% vs. 52%). Finally 17 patients with multivessel disease but without proximal LAD lesion did not differ in any of the above mentioned parameters, when compared to the patients with single‐vessel disease and proximal LAD stenosis. We conclude that impaired left ventricular function does not sufficiently explain the high risk of sudden death in postmyocardial infarction patients. The coronary and functional status of the surviving myocardium has to be taken into consideration as well.
Acute effects of alcohol on left ventricular dynamics during isometric exercise in normal subjects
Authors: Kupari M. , HeikkilÄ J. , Ylikahri R. 
Published: February 2009

AbstractThe aim of this study was to assess whether drinking social amounts of alcohol impairs myocardial contractility in normal humans. To that end, 17 healthy volunteers performed isometric handgrip exercise before and 60 minutes after an intake of 1 g/kg body weight of ethanol within 60 minutes. Left ventricular M‐mode echocardiogram, systolic time intervals, and sphygmomanometric arterial blood pressure were recorded before and at the end of 4‐min handgrip at 30% of maximum voluntary contraction. The blood ethanol concentration (mean±SD) was 24.4±2.0 mmol/liter. At rest, ethanol increased heart rate (p>0.05) and decreased left ventricular end‐diastolic diameter (p>0.05), end‐systolic diameter (p>0.01), and circumferential systolic wall stress (p>0.05). The indices of left ventricular performance were unchanged except for the maximum circumferential fiber shortening velocity which was increased after ethanol (p>0.001). The cardiac response to isometric exercise was similar before and after ethanol except that the handgrip‐induced rise in systolic wall stress was smaller postingestion (p>0.05). This study does not support the view that drinking small to moderate amounts of alcohol brings about myocardial depression in normal humans. Although preload, afterload, and heart rate were altered by ethanol at rest>d>Myocardial contractility was not impaired even during the afterload stress imposed by isometric exercise.