bluuebunny/crossref_metadata_2025_split huggingface dataset:
A double‐blind trial of disopyramide, procaineamide and digoxin in paroxysmal supraventricular tachycardia
Authors: Craig M. W. Millar , Raftery E. B. 
Published: October 2013

AbstractA double‐blind cross‐over study has been performed in 10 patients with an established diagnosis of paroxysmal supraventricular tachycardia to compare the effectiveness of three active agents with placebo. The drugs were administered in random sequence for two‐week periods with three‐day washout intervals and in standard dose regimes as recommended for prophylaxis by authoritative works on the subject. The results suggest that digoxin is ineffective at the recommended dosage. Procaineamide was effective in controlling some arrhythmias, but disopyramide was the most effective agent studied. All these patients showed a mixture of arrhythmias, and also had a lot of ectopic activity. Arrhythmic activity is erratic and unpredictable, and a larger number of patients would need to be studied for long periods of time to obtain enough data for valid statistical assessment.
Myocardial imaging with 134mCesium. Comparison of scintigraphic and cineradiographic results
Authors: Eybel C. E. , Turner D. A. , Rayudu G. V. S. , Fordham E. W. , Friedman A. M. , Messer J. V. 
Published: October 2013

AbstractThirty‐four patients had noninvasive myocardial perfusion imaging at rest using 134mCs. The results were compared with the results of coronary cineangiography and left ventriculography. All 21 patients who had abnormal left ventriculograms had corresponding myocardial imaging defects. This group included 14 patients with electrocardiographic evidence of either an old inferior, anteroseptal, anterior, or anterolateral myocardial infarction. Thirteen patients had normal left ventriculograms: this group included 6 patients with 75% or greater obstruction of one or more coronary arteries and 7 patients with normal or insignificantly diseased vessels. Only 2 of these patients had abnormal myocardial images: both had severe obstruction of the proximal left anterior descending artery without collateral filling of this vessel. In the resting patient who has 134mCs myocardial imaging, we concluded that we primarily are visualizing varying degrees of scarred myocardium rather than reversibly ischemic myocardium.
Antianginal efficiency of nifedipine with and without a beta‐blocker, studied with exercise test. A double‐blind, randomized subacute study
Authors: Ekelund L.‐G. , Orö L. 
Published: October 2013

AbstractTwenty‐one patients, mean age 60.3 years, with stable angina pectoris earlier treated with beta‐blockers, were investigated with standardized exercise tests to evaluate the action of nifedipine alone and in combination with a beta‐blocker. The first exercise test was performed 3 weeks after treatment with the patient's usual beta‐blocker. Following this, the patients were tested twice after a double‐blind cross‐over 3‐week trial with nifedipine and placebo. The patients were subsequently treated for 3 weeks with nifedipine 10 mg 3 times daily or placebo and then performed an exercise test. During the 4th period of 3 weeks the patients took a combination of nifedipine, 10 mg 3 times daily, and their usual beta‐blocker and then performed the final exercise test.Nifedipine alone raised the heart rate by 5 beats/min at rest and diminished the systolic blood pressure at rest by 17 mm Hg. During exercise at comparable load the heart rate did not change significantly, but the systolic blood pressure decreased with 22 mm Hg. The exercise tolerance expressed as total work increased on an average by 20%, range −14 — +194%. Nifedipine in combination with a beta‐blocker gave a further decrease in the systolic blood pressure, totally 37 mm Hg at comparable load. The exercise tolerance increased more, totally by an average of 41%. There was a significant correlation between basal values for systolic blood pressure registered during the placebo period at rest and the percentage change in total work. The atrioventricular conduction time did not change significantly compared to placebo during treatment with nifedipine or the combination nifedipine + beta‐blocker. No serious side‐effects were observed during the study.
Changes in left ventricular diastolic function in coronary artery disease with and without angina pectoris assessed from exercise ventriculography
Authors: Tebbe U. , Hoffmeister N. , Sauer G. , Neuhaus K. L. , Kreuzer H. 
Published: October 2013

AbstractIn 11 normals and 43 patients with coronary artery disease left ventricular (LV) diastolic pressure–volume (P–V) curves were obtained from biplane ventriculograms and simultaneous high fidelity pressure measurements.During exercise ventriculography 20 patients had angina pectoris (group B), and 16 patients were asymptomatic (group A). At rest there were no akinetic segments in 28 patients (group C), and an akinetic segment was found in 15 (group D). With different total work loads (951 ± 134 and 2100 ± 245 kpm in groups B and A), LV minimal and end‐diastolic pressures and corresponding ventricular volumes increased to a similar extent in patients with and without angina during exercise ventriculography. With comparable work loads (1,296±221 and 1,494±195 kpm in groups C and D) the mean increase in diastolic pressure and volume was larger in group D, which corresponded to the more depressed LV resting function.Shifts in the diastolic P–V relationship with exercise were quantitated from the constants a and b of the linear log P–V relationship. In the control group, a and b did not change significantly, but in all CAD groups a significant decrease in a and a significant increase in b were observed during exercise. These changes were more pronounced in groups B and D, but were statistically significant in group A, too.While no patient with angina had an unchanged diastolic P–V relationship, as many as 12 patients had significant P–V shifts in the absence of angina. Eight of these were expected to develop myocardial ischemia with exercise as judged from their coronary artery stenosis and ventriculograms. A similar correlation was found for the diastolic P–V alterations and the exercise ECG. Fourteen patients without any ST‐segment change during exercise showed significant P–V shifts, while no patient with signs of ischemia in the ECG had an unchanged P–V curve.We conclude that LV diastolic function is more sensitive to myocardial ischemia than both angina pectoris and the exercise ECG. An inappropriate increase in LV filling pressure with exercise probably reflects myocardial ischemia even in the absence of angina pectoris and ST‐segment depression in the ECG.
Measurement of heterogeneous myocardial blood flow
Authors: Schanzenbächer P. , Klocke F. J. 
Published: October 2013

AbstractInert gas measurements of myocardial blood flow have been compared to simultaneous radioactive microsphere flow measurements. Average flow per unit weight agreed within 20% in 20 of 24 comparisons. With the inert gas technique flows up to 580 ml/min/100 g could be measured. Semilogarithmically plotted desaturation curves were distinctively curvilinear. It is concluded that the shape of the washout curve is a function of the underlying flow pattern.
Global and regional left ventricular contractility and coronary collaterals in stable ischemic heart disease
Authors: Nieminen M. S. , Valle M. , Lassila E. , Heikkilä J. , Hekali P. , Frick M. H. 
Published: October 2013

AbstractGlobal and regional left ventricular contractility were determined in 43 patients with stable ischemic heart disease utilizing echocardiography. Indices of contractility from multiple left ventricular segments were related to both the coronary obstructions and the presence of collateral supply. The impact of past myocardial infarction was taken into account. Global left ventricular contractility decreased with increasing degree of coronary obstructions (r = 0.69; p<0.001). In patients with collateral supply global contractility decreased with increasing degree of collateral supply (r = 0.59; p<0.001).Analysis of myocardial regions corresponding to the three major coronary arteries disclosed that past myocardial infarction resulted in decreased contraction indices (p<0.01‐0.001). This effect was related neither to the degree of obstruction once it exceeded 50% nor to the presence of collateral supply. A comparison of patients with single‐vessel disease, no prior infarction, and similar coronary obstructions revealed no differences in regional contractility whether collaterals were present or not. Regional contractility decreased in linear fashion in relation to increasing coronary obstructions (p<0.001). Collaterals became angiographically visible when the obstructions exceeded 75% but their appearance did not prevent the deterioration of contractility.It is concluded that collaterals are visualized by angiography when the coronary artery obstructions exceed 75%. Their presence does not, however, affect the global or regional decline in contractility associated with increasing severity of coronary artery obstructions. Moreover, they do not attenuate the decline in regional contractility associated with prior myocardial infarctions.
Decrease in cardiotoxicity of contrast media in coronary angiography by addition of calcium ions: A combined experimental and clinical study
Authors: Zipfel J. , Baller D. , Blanke H. , Karsch K. R. , Rentrop P. , Hellige G. 
Published: October 2013

AbstractThe cardiotoxicity of commonly used contrast media such as sodium methylglucamine diatrizoate is related to nonphysiologic concentrations of ions and high osmolality. Following injection there is an excessive decrease in ambient calcium which disturbs the extracellular Na+/Ca2+ ratio and results in myocardial depression. In animal studies (anesthetized, intact mongrel dogs) this cardiodepressive effect could be fully compensated by adding 22.5 mEq/1 of ionic calcium to the contrast medium.In 16 patients studied for coronary artery disease (CAD) 72 injections of sodium methylglucamine diatrizoate, mainly in the left coronary artery, were thoroughly investigated. There was marked depression of left ventricular pressure (‐22%) and (dP/dt)max (‐27%), and marked heart rate slowing (‐29%). Added calcium in the concentration cited reduced significantly (p<0.001) the myocardial depression to −15% and −13%, respectively, but did not completely compensate it. The heart rate slowing was not altered significantly. It was concluded that the addition of calcium may be helpful when studying high‐risk patients and using high injection volumes.
Comparison of myocardial potassium and thallium flux as studied by tracer methods
Authors: Nitsch J. , Steinbeck G. , Lüderitz B. 
Published: October 2013

AbstractAlthough myocardial scintigraphy with 201thallium is widely applied in humans, the behavior of thallium at the cellular level is still under discussion. We compared the transmembrane fluxes of potassium and thallium in the isolated papillary muscle of guinea pigs. A qualitative conformity exists between potassium and thallium fluxes with respect to heart rate and temperature. Quantative comparison revealed a decreased flux rate of thallium for efflux when compared with potassium. The time dependence of thallium influx indicates that thallium scintigraphy of the myocardium reflects mainly an extracellular distribution.
Enzyme activities of human myocardium: Creatine kinase and hexose phosphate isomerase
Authors: Haralambie G. , Uy J. 
Published: October 2013

AbstractCreatine kinase (CK) and hexose phosphate isomerase (PHI) activities were determined in 36 samples of human heart muscle obtained from patients during cardiovascular surgery. With one exception, CK activities were higher than any reported so far in the literature (papillary muscle, left ventricle: 2,521 ±776 IU/g wet weight at 37°C). PHI Activities, the first time measured, are comparable to those in skeletal muscle (200‐400 U/g, higher in papillary muscle than in the right auricle). The activities of both enzymes determined correlate significantly (all samples considered together: r = 0.773; p<0.001). Results are discussed with respect to their possible clinical interest as well as their significance for myocardial metabolism.
Hemophilus influenzae pericarditis
Authors: Sink J. D. , Spray T. L. , Rankin J. S. 
Published: October 2013

AbstractAlthough Hemophilus influenzae infections have long been considered to be a disease of childhood, recent reports have demonstrated an increasing frequency of serious Hemophilus influenzae infections in adults. A case of purulent H. influenzae pericarditis in a previously healthy adult without evidence of concurrent H. influenzae infection is reported.
Digital subtraction angiography: Present and future uses in cardiovascular diagnosis
Authors: Myerowitz P. D. 
Published: October 2013

AbstractDigital subtraction angiography (DSA) has been proved to be an effective means of visualizing the cardiovascular system following intravenous injection of contrast material. Excellent quality images have been obtained of the left ventricle, the thoracic aorta and its major branches, the carotid arteries, the abdominal aorta and its major branches, lower extremity vessels, and intracerebral vessels. Avoiding the risks and discomforts of direct arterial puncture and the need for hospitalization, DSA is safer and more economical than standard arteriography. It is, therefore, useful both as a screening tool and, in many patients, as a diagnostic tool for the evaluation of vascular disease. Left ventricular studies provide excellent qualitative and quantitative evaluation of left ventricular function. Arterial injections of contrast have provided excellent quality images of the vascular tree with low volume dilute contrast material. Lower extremity vessels not visualized by standard arteriography have been seen following intra‐arterial contrast injections using DSA. Aortic root injections have been used to demonstrate coronary arteries and coronary artery bypass grafts. Although intravenous injections of contrast have shown coronary artery bypass graft patency with reasonable success, they have not proved useful at this point in defining the exact anatomy. Other video techniques following arterial injections of contrast have been used to calculate vessel flows. Although coronary artery images in animal studies following intravenous contrast injection are improving, they are still not of diagnostic quality. Digital subtraction angiography, therefore, has proved itself a useful adjunct to standard arteriographic techniques. Its future potential has not yet been defined.
Echocardiography in patients with acute cerebral events
Authors: Bergeron G. A. , Shah P. M. 
Published: October 2013

AbstractThe question of the clinical and economic feasibility of echocardiographic screening for cardiac disease in patients with symptoms of acute cerebral events was assessed by recording M‐mode and two‐dimensional (2D) echocardiograms in 170 patients. Patients with transient ischemic attacks or cerebral infarctions were included. Of the patients with satisfactory echocardiograms, 96 (56%) had normal diagnostic findings; 74 (43%) had cardiac disorders possibly related to the acute cerebral event. There were 4 patients who fulfilled the standard criteria for mitral valve prolapse and 7 patients who were identified as having probable cardiac thrombosis or vegetation, or both. Thus, M‐mode and two‐dimensional echocardiography was of limited value in patients referred for these studies for screening to exclude mitral valve prolapse and cardiac thrombosis or vegetation. Although a diverse range of cardiac disorders was demonstrated that may be associated with cerebral ischemia, the overall low yield does not support such screening and should be reserved for selected patients.
Controversies in hypertension: Mild hypertension, isolated systolic hypertension, and the choice of a step one drug
Authors: Cressman M. D. , Gifford R. W. 
Published: October 2013

AbstractThe realization that cardiovascular morbidity and mortality increases in patients with mild elevation of either systolic or diastolic blood pressure has led to a consideration to treat millions of patients with mild diastolic or isolated systolic hypertension. The cost of administering a successful antihypertensive treatment program and the potential adverse effects of pharmacologic agents is of great concern. It has been emphasized that the risk of premature mortality differs in individual patients according to the number of associated cardiovascular risk factors at any level of blood pressure. This has led to a suggestion that only high risk patients be treated. However, a significant number of low risk patients with mild hypertension develop a more severe or complicated form of their disease even over a follow‐up period of five to ten years. There is no good way to identify these patients. Trials of antihypertensive therapy suggest a beneficial effect of blood pressure lowering in mild hypertension. No trials of antihypertensive therapy in elderly patients with isolated systolic hypertension have been reported, but the elevation in systolic blood pressure appears to be an independent risk factor for cardiovascular mortality. Even the choice of the first step agent in treatment is debatable. Diuretics or beta blockers effectively lower blood pressure in the majority of hypertensive patients, particularly if modest dietary sodium restriction is achieved. The incidence of side effects, either symptomatic or biochemical, is similar but diuretics are unquestionably cheaper and probably more effective. Successful application of an antihypertensive treatment program may continue to reduce our unacceptably great incidence of cardiovascular disease.
Coronary hemodynamic data in ischemic heart disease according to ischemic behavior during pacing
Authors: Cribier A. , Berland J. , Cazor J. L. , Letac B. 
Published: October 2013

AbstractIn order to study the circulatory changes induced by maximal atrial pacing in coronary patients, coronary sinus blood flow (CBF) measured by continuous thermodilution, lactate extraction coefficient (K), arteriovenous difference in oxygen (AVO2 diff), and aortic blood pressure (BP) were measured at basal state and at maximal heart rate (HRmax) in 11 patients without coronary disease (group I) and in 28 patients with severe coronary lesions, divided into two groups according to the absence (group IIa) or the presence (group IIb) of chest pain and ST‐segment depression at HRmax. K was inverted in group IIb (24±17% vs −23±39%, p < 0.001), but remained unchanged in group I and group IIa. Despite similar HRmax, percent increase in CBF was significantly lower in group IIb (54±34%), than in group I (113±54%, p < 0.01). This contrasts with the higher values of the product of heart rate times systolic blood pressure (HR × SBP) as well as of diastolic blood pressure (DBP) in group IIb. The decrease in coronary resistances was lower in group IIb than in group I (p < 0.001), and also lower than in group IIa (p < 0.05). The ratio MO2 × CBF/systolic BP × HRmax was significantly lowered only in group IIb (p < 0.001) confirming the imbalance between myocardial oxygen supply and oxygen demand. In coronary patients, myocardial ischemia induced by atrial pacing is related to an insufficient increase in CBF, well evidenced by continuous thermodilution.
Cholinium‐based Supported Ionic Liquid Membranes: A Sustainable Route for Carbon Dioxide Separation
Authors: Tomé Liliana C. , Patinha David J. S. , Ferreira Rui , Garcia Helga , Silva Pereira Cristina , Freire Carmen S. R. , Rebelo Luís Paulo N. , Marrucho Isabel M. 
Published: October 2013

AbstractAiming at full sustainability of CO2 separation processes, a series of supported ionic liquid membranes based on environmentally friendly cholinium carboxylate ionic liquids were successfully prepared. Their gas permeation properties were measured and high permselectivities were obtained for both CO2/CH4 and CO2/N2.
Clinical Considerations on Anticoagulation Management in Cardiovascular Diseases During Pregnancy
Authors: Goland Sorel , Zilberman Liaz , Elkayam Uri 
Published: October 2013

ABSTRACT

Clinical Development Phases I‐III Regulatory, Quality, Manufacturing

Pregnancy‐associated thrombosis is an important cause of morbidity and mortality during pregnancy. All anticoagulation options are associated with risks and benefits. Thus, although anticoagulation therapy is an important component of the management of thrombotic complications in pregnancy, it is associated with fetal and maternal complications. Therefore, pregnancy poses a serious therapeutic dilemma for both physicians and their patients. This review summarizes the available data on anticoagulation therapy for thromboembolic prophylaxis in pregnant women focusing on cardiovascular disorders, especially on treatment strategy in pregnant women with mechanical heart valves.
Platelet Fragmentation: A Novel Opinion for Thrombosis Therapy
Authors: Zhang Wei 
Published: October 2013

ABSTRACT

Preclinical Research

Ischemic cardio‐cerebrovascular events represent a leading cause of morbidity and death worldwide. Given the central role of platelets in thrombus formation, antiplatelet therapy has great clinical value for the treatment of thrombotic diseases. Currently, most antiplatelet therapies aim at preventing thrombus formation by inhibiting platelet function, but not at direct thrombolysis; the latter is highly desirable clinically. In this article, the discovery of a cellular and molecular mechanism inducing platelet fragmentation is reviewed, which has led to the development of a novel, potential therapeutic approach to improve current thrombosis therapy.
The Remarkable Hyperchromicity of Ketohydrazone Dyes and Pigment Lakes Derived from 4‐Morpholino‐2‐naphthol
Authors: Aiken Stuart , Gabbutt Christopher D. , Gillie Lisa J. , Heywood Jonathan D. , Jacquemin Denis , Rice Craig R. , Heron B. Mark 
Published: October 2013

AbstractThe syntheses of a series of new ketohydrazone dyes and pigment lakes with a unique structural motif derived from 4‐morpholino‐2‐naphthol are described. The morpholine substituent is responsible for the hypsochromically shifted absorption maxima with significantly enhanced molar extinction coefficients of the new dyes; this conclusion is supported by time‐dependent DFT (TD‐DFT) simulations. The location of the morpholine substituent at a sterically demanding site in the pigment lake obstructs further coordination of the bridging sulfonate groups in the solid state and prevents the formation of a 1‐dimensional polymeric system, which is common for other pigment lakes.
Evaluating fire blocking performance of barrier fabrics
Authors: Nazaré Shonali , Pitts William , Flynn Shaun , Shields John. R. , Davis Rick D. 
Published: October 2013

SUMMARYA series of evaluations were performed on different types of barrier fabrics (BFs) used in soft furnishings. Fundamental properties that influence the heat transfer characteristics of barrier material as it relates to thermal protection of cushioning components in upholstered products are discussed. This is important to enable a priori selection of BFs such that a final upholstered product complies with flammability regulations.Heat transfer measurements are used to determine effectiveness of materials to be used as barrier materials. A new bench‐scale composite test method is also described to assess qualitative fire blocking performance of BFs. When tested for heat transfer characteristics, the area density and thickness of BFs show strong influence. However, when tested as a composite in a mock‐up assembly, the BFs considered in this study showed a clear distinction between active and passive BFs. In the case of chemically active BFs, the construction parameters and material properties such as thickness, air permeability, and heat transfer were of little significance. In the case of passive BFs, however, these parameters became decisive. Results from this study suggest that if the BF is not an active fire barrier, then the amount of heat transferred through BF is critical. Copyright © 2013 John Wiley & Sons, Ltd.