bluuebunny/crossref_metadata_2025_split huggingface dataset:
Attenuated severity of new acute ischemic events in patients with previous coronary heart disease receiving long‐acting nitratesa
Authors: Garc ía‐Dorado David , Permanyer‐Miralda GaietÀ , Brotons Carles , Calvo Francisco , Campreci ós Marta , Oliveras Juan , Teresa Santos M. , Moral Irene , Soler‐Soler J. 
Published: February 2009

AbstractBackground: Platelet aggregation and secondary vasoconstriction are key events in the genesis of acute coronary syndromes.Hypothesis: Since nitrates have vasodilatory and antiaggregant effects, treatment with long‐acting nitrates at the time of onset of acute coronary syndromes could be associated with attenuation of their severity.Methods: A consecutive series of 533 patients with acute coronary syndrome and past history of coronary artery disease admitted to the Cardiology Service of a general hospital was studied. A specific questionnaire assessed the use of nitrates and other relevant drugs, as well as other clinical variables. The diagnosis of unstable angina or acute myocardial infarction (MI) was established according to clinical, electrocardiographic, and enzymatic criteria.Results: In the whole cohort, 169 patients had MI and 364 had unstable angina. Previous use of long‐acting nitrates was significantly more common in patients with unstable angina (56%) than in those with MI (37%) (p<0.0001). Multivariate analysis identified being a nonsmoker [odds ratio: 95%, confidence limits (CL) 0.37, 0.23–0.59], previous unstable angina (CL 0.62, 0.41–0.92), use of aspirin (CL 0.58, 0.41–0.92), and use of long‐acting nitrates (CL 0.61, 0.40–0.93) as the independent predictors of the development of unstable angina rather than MI; of these the combination of nitrates and aspirin was the strongest predictor.Conclusions: Long‐acting nitrates as well as aspirin are suggested to have a protective or modifying effect on the development of acute coronary syndromes, favoring unstable angina rather than acute MI.
Transesophageal echocardiography for the evaluation and management of patients with cerebral ischemia
Authors: Rahmatullah Amin F. , Rahko Peter S. , Stein James H. 
Published: February 2009

AbstractTo prevent recurrent strokes and transient ischemic attacks, considerable attention is devoted to investigating the etiology of acute cerebral ischemia in the large subpopulation of patients without an easily identifiable cause. In general, transthoracic echocardiography is an insensitive tool for the evaluation of patients with cerebral ischemia, unless clinical signs and/or symptoms of cardiac disease are present. Transesophageal echocardiography (TEE), because of its increased sensitivity for aortic arch atheromata, atrial septal pathology, left atrial thrombi, and valvular abnormalities, is the preferred cardiac imaging modality, especially in young patients, older patients with hypertension or systemic atherosclerosis, and patients with prosthetic heart valves. This paper reviews the prognostic and therapeutic impact of TEE in patients with cerebral ischemia, specifically focusing on the ability of information obtained by this technique to alter patient management and improve risk stratification.
The effects of metoprolol and captopril on heart rate variability in patients with idiopathic dilated cardiomyopathy
Authors: Jansson Kjell , Östlund Rolf , Nylander Eva , Dahlström Ulf , Hagerman Inger , Karlberg Karl‐Erik , Nyquist Olof 
Published: February 2009

AbstractBackground: The effects of treatment with captopril or metoprolol on heart rate variability (HRV) were investigated in 38 patients (29 men and 9 women) with mild to moderate symptoms of heart failure due to idiopathic dilated cardiomyopathy (DCM).Hypothesis: The aim of the study was to investigate and compare the effects of the angiotensin‐converting enzyme inhibitor captopril with those of the selective beta‐adrenergic receptor blocker metoprolol on HRV in patients with idiopathic DCM.Methods: Heart rate variability was analyzed in the time and frequency domains from 18 h of Holter monitoring before randomized treatment was started, after 6 months of therapy, and 1 month after therapy was stopped.Results: Captopril treatment increased HRV expressed as total power and low‐frequency power in the frequency domain. There was no change in the time domain. In the metoprolol group, there was a pronounced increase in both time‐and frequency‐domain indices of HRV. The increase in total power was partly maintained 1 month after therapy was stopped in both treatment groups.Conclusion: Treatment with captopril and metoprolol increases HRV in patients with DCM. This effect seems to be maintained for at least 1 month after therapy is stopped. The increase in HRV seems to be more pronounced with metoprolol, and the two different pharmacologic approaches may have additive effects that are of prognostic importance in patients with heart failure.
Paradoxical behavior of the QT interval during exercise and recovery and its relationship with cardiac memory
Authors: Moleiro Federico , Misticchio Francesca , Torres Jose M. , Pulido Moises , Luque Milagros , Rodriguez Ana , Mendoza Ivan , Guerrero Julio , Ruesta Victor , Castellanos Agustin , Myerburg Robert J. 
Published: February 2009

AbstractBackground: Few studies have dealt with the behavior of the corrected (QTc) and uncorrected QT intervals during exercise and recovery.Hypothesis: Based on previously published dynamics of the QT interval during treadmill testing, this study attempted to reevaluate the computer‐proposed underlying mechanisms of these dynamics and to determine whether the so‐called memory phenomenon could be operative in some subjects without evidence of structural heart disease.Methods: This study included 42 unmedicated healthcare volunteers, 23 men and 19 women aged between 20 and 42 (mean 31.7) years. All had normal physical examinations, x‐rays, and transthoracic echocardiograms. The electrocardiograms were also normal with 12‐lead QT interval dispersions of <90ms.Results: During exercise and recovery, the behavior of the QT intervals permitted the categorization into two groups. In Group 1 (31/42; 73.8% of subjects) the uncorrected QT interval showed a biphasic pattern consisting of a gradual decrease during incremental exercise followed by a gradual increase during recovery. In contrast, the QTc interval had a triphasic pattern resulting from a slight increase during the early phase of exercise, a gradual decrease at the highest rates, and a final increase during recovery as the rate slowed to control values. In Group 2 (11/42; 36.2% of subjects) the behavior was considered as paradoxical since the uncorrected QT interval displayed in a triphasic pattern whereas the QTc interval yielded a tetraphasic pattern due to the fact that both showed a second decrease during recovery while the rate was decreasing.Conclusions: Analysis of dynamics behavior of the QTc and the uncorrected QT intervals during exercise showed that some normal subjects had a paradoxical behavior which, because of its temporal relation to the phases of exercise, could be an expression of the so‐called memory phenomenon.
Morning attenuation of endothelium‐dependent, flow‐mediated dilation in healthy young men: Possible connection to morning peak of cardiac events?
Authors: Etsuda Hirokuni , Takase Bonpei , Kusano Hiroyuki , Hamabe Akira , Kuhara Ryoji , Akima Takashi , Matsushima Yoshihiro , Arakawa Koh , Satomura Kimio , Ohsuzu Fumitaka , Kurita Akira , Uehata Akimi 
Published: February 2009

AbstractBackground and hypothesis: Brachial artery flow‐mediated dilation (FMD), a noninvasive, widely used clinical index of endothelial function and magnitude of FMD, has been reported to be closely related to many coronary risk factors and coronary atherosclerosis. However, there has been no study that examines the diurnal change of FMD. We designed this study to reveal the diurnal variation of FMD in healthy volunteers.Methods: We examined FMD in response to reactive hyperemia by high resolution ultrasound in 13 healthy young men (age 25–32) at four different times over the course of a day.Results: Mean measures of brachial artery FMD was 4.0% at 8:00, 5.3% at 12:00, 9.7% at 17:00, and 6.9% at 21:00 hours. Flow‐mediated dilation at 8:00 and at 12:00 hours was significantly lower than that at 17:00 (p <0.05).Conclusions: These results show that endothelial function has diurnal variation and is significantly attenuated in the morning. Morning attenuation of endothelial function should be recognized in clinical research and may play an important role in the circadian variation of the occurrence of acute cardiovascular events.
Comparison of coronary collateral circulation in diabetic and nondiabetic patients suffering from coronary artery disease
Authors: Melidonis A. , Tournis S. , Kouvaras G. , Baltaretsou E. , Hadanis S. , Hajissavas I. , Tsatsoulis A. , Foussas S. 
Published: February 2009

AbstractBackground and hypothesis: Although it is well established that diabetes mellitus (DM) induces more severe coronary artery disease (CAD), it is not known whether it contributes to the development of coronary collateral circulation. The present study examines coronary collateral circulation in diabetic and nondiabetic patients with angiographically verified CAD.Methods: The study group consisted of 463 diabetic patients (382 men, 81 women) with a mean age of 60.3 ± 8.8 years, and 227 nondiabetic subjects (159 men, 68 women) with a mean age of 59.2 ± 9 years. The extension and functional capacity of coronary collateral circulation was assessed according to the Cohen and Rentrop grading system of 0 to III.Results: We found that diabetic patients had grade III collateral circulation more frequently than nondiabetic subjects (13.2 vs. 8.5%, p<0.01). This finding was even more pronounced in diabetic men aged < 55 years compared with both nondiabetic men (20 vs. 3.4%, p<0.001) and diabetic women (20 vs. 2.2%, p<0.001). Grade III collateral circulation was found to develop mainly at the left anterior descending (LAD) coronary artery and the right coronary artery (RCA), where complete occlusions of coronary arteries usually occur.Conclusions: Diabetic patients with CAD develop more extensive coronary collateral circulation than nondiabetic subjects, especially men aged <55 years. The collateral circulation mainly develops at the LAD and RCA.
Pocket infection complicating inadvertent transarterial permanent pacing. successful percutaneous explantation
Authors: Trigano J.‐A. , Paganelli F. , Fekhar S. , Gelisse R. , Alimi Y. 
Published: February 2009

AbstractThis report describes a patient admitted for the treatment of a pocket infection occurring 5 months after a dual chamber pacemaker implantation. The ventricular lead had been inadvertently placed into the left ventricle through the arterial system. After careful examination using transesophageal echocardiography and left heart angiogram, successful percutaneous extraction was performed without complication.
The association between the on‐site availability of cardiac procedures and the utilization of those services for acute myocardial infarction by payer group
Authors: Canto John G. , Rogers William J. , Roseman Jeffrey M. , Zhang Yuan , French William J. , Gore Joel M. , Chandra Nisha C. 
Published: February 2009

AbstractBackground: Prior studies have suggested that in‐hospital availability may be an important determinant for the use of invasive cardiac services; however, whether this association is influenced by payer status remains unclear.Hypothesis: The interaction of payer status and the on‐site availability of coronary arteriography is associated with increased utilization of this procedure.Methods: In‐hospital availability and utilization of coronary arteriography was ascertained in 275,046 patients with acute myocardial infarction (AMI) enrolled in the National Registry of Myocardial Infarction 2 from June 1994 to April 1996. Logistic regression analyses were performed to determine the association between the on‐site availability of cardiac catheterization at the initial hospital and subsequent utilization of coronary arteriography. Similar analyses were performed within Medicare, Medicaid, Commercial, Health Maintenance Organization (HMO), and Uninsured payer groups.Results: Patients initially admitted to hospitals having on‐site cardiac catheterization facilities were almost twice as likely to receive coronary arteriography as patients admitted to hospitals without such facilities and later transferred out [un‐adjusted odds ratio (OR) = 1.69,95% confidence interval (CI) 1.66–1.73, p < 0.0001; adjusted OR = 2.08,95% CI 2.01–2.15, p < 0.0001]. Furthermore, this relationship of increased utilization with greater availability was evident within each payer group, but was highest among those with Commercial insurance and lowest among Medicaid recipients: [Commercial insurance (OR = 2.19,95% CI 2.07–2.31, p < 0.0001); Uninsured (OR = 1.74,95% CI 1.57–1.92, p < 0.0001); HMO (OR = 1.67,95% CI 1.54–1.82, p < 0.0001); Medicare 1.60,95% CI 1.55–1.64, p < 0.0001); Medicaid (1.46,95% CI 1.29–1.65, p < 0.0001)].Conclusions: Our results show a strong association between in‐hospital availability and subsequent utilization of invasive cardiac procedures following AMI among all patients, but the strength of these associations varied among payer status.
Management strategies in unstable coronary artery disease—Current problems and future directions
Authors: Verheugt F. W. A. , Becker R. C. , Bertrand M. E. , Bode C. , Chesebro J. H. , Cleland J. G. F. , Conti R. , Hillis W. S. , Klein W. , Maseri A. , Turpie A. G. G. , Wallentin L. , Waters D. D. 
Published: February 2009

AbstractUnstable coronary artery disease continues to pose a major challenge to clinicians. The advent of new therapies, such as percutaneous transluminal coronary angioplasty, low‐molecular‐weight heparins, and glycoprotein IIb/IIIa inhibitors, provides new management options for this indication but also raises new questions with regard to optimal management. Prospective randomized trials with well‐defined, long‐term outcome measures and a means of identifying which patients will derive most benefit from each treatment, together with a means of rapid and clear dissemination of study results and implications, are required in order to advance the management of unstable coronary artery disease.
Effect of amlodipine on exercise‐induced platelet activation in patients affected by chronic stable angina
Authors: Sanguigni Valerio , Gallù Mariacarla , Sciarra Luigi , Cannata Dario , Strano Antonio , Principe Domenico Del , Menichelli Adriana , Palumbo Giovanni 
Published: February 2009

AbstractBackground: Literature concerning exercise‐induced platelet activation in chronic stable angina is somewhat confusing. The reason lies in the type of exercise as well as in methodological problems. A powerful, recently introduced procedure to detect platelet activation is flow cytometry. Platelet response to activating factors is mediated by calcium uptake; however, calcium antagonist effect on platelet activity is still unclear.Hypothesis: The study was undertaken to investigate exercise‐induced platelet activation before and after treatment with amlodipine in chronic stable angina.Methods: Twenty patients with chronic stable angina were entered into the study. Each subject underwent a symptom‐limited cycloergometer stress test following a washout period of 2 weeks. Blood samples were collected before and immediately after exercise. All subjects were then randomized into two groups of 10 patients each, with Group 1 and Group 2 taking amlodipine 10 mg/day, and placebo for 4 weeks, respectively. They subsequently underwent a second exercise stress test, and blood samples were obtained before and immediately after exercise. Flow‐cytometric evaluation of platelet activity was performed in order to recognize GMP‐140 expression on platelet membrane.Results: Strenuous exercise induced a significant increase in platelet activation in all subjects prior to therapy. No significant differences were observed in platelet activity at rest between Groups 1 and 2, whereas a significant decrease in exercise‐induced platelet activation was demonstrated in Group 1 compared with Group 2.Conclusion: Our data provide evidence of the favorable effect of amlodipine on exercise‐induced platelet activation in patients affected by chronic stable angina.
Transvenous atrial defibrillation—techniques and clinical applications
Authors: Tse Hung‐Fat , Lau Chu‐Pak , John Camm A. 
Published: February 2009

AbstractAtrial fibrillation (AF) is the most common arrhythmia requiring treatment. The most desirable therapy may be restoration and maintenance of sinus rhythm. Limitations of the current methods for cardioversion of AF have prompted the development of transvenous atrial defibrillation (TADF) as an alternative and more effective technique for converting AF. Recent advances in the technique of TADF, particularly in the design and configuration of the electrodes, and the use of an optimal biphasic shock waveform have dramatically improved the efficacy of TADF for the termination of all types of AF. The reduction in voltage and energy requirements for cardioversion by TADF may allow the procedure to be performed with little or no sedation and the risk of general anesthesia may be avoided. Both experimental and clinical studies have demonstrated the feasibility, safety, and efficacy of using TADF as a new temporary or “permanent” mode of electrical therapy for AF. It has several potential applications, from acute termination of AF in the electrophysiology laboratory and in patients who have failed to respond to external cardioversion, to its use as an implantable device for treating recurrent AF. This article reviews the current technique and clinical applications of TADF for treatment of AF.
Effects of isosorbide dinitrate on electrocardiography, hemodynamics, and ventilation in patients with exercise‐induced elevation of pulmonary artery wedge pressure
Authors: Josrgensen Lars H. , Thaulow Erik , Refsum Harald E. 
Published: February 2009

AbstractBackground: The mechanisms underlying exertional hyperpnea in patients with coronary artery disease and transient left ventricular dysfunction are still not fully understood.Hypothesis: The study was undertaken to investigate whether the ventilatory response to exercise reflects the effects of acute medical treatment of exercise‐induced left ventricular dysfunction, and to evaluate mechanisms relevant to excessive exertional ventilation.Methods: In 11 male patients, aged 65.2 pL 6.0 years, all with pulmonary artery wedge pressure (PAWP) < 25 mmHg and ST depression < 2 mm during moderate supine exercise, ventilation ( ), oxygen uptake (Vo2), hemodynamics, electrocardiogram (ECG), and arterial and mixed venous blood gases were examined during supine rest and exercise, before and at hourly intervals after peroral intake of 30 mg isosorbide dinitrate (ISDN). Six similar patients were examined with the same protocol without ISDN administration and comprised a control group.Results: Before administration of ISDN, exercise PAWP was 35.3 pL 5.9 mmHg, ECG showed 2.77 pL 1.06 mm ST depression, and V/Vo2was 31.8 pL 4.8 l/l. One h after ISDN administration, exercise mean PAWP was 11.0 pL 2.5 mmHg (p < 0.001), ST depression 0.59 pL 0.8 mm (p < 0.001), whereas V/Vo2was unchanged, 30.1 ± 5.3 l/l. Two h later, PAWP remained reduced and there were only minor ST depressions, while V/Vo2remained high. Exercise cardiac index (CI) and mixed venous oxygen tension (Pvo2), initially 4.7 pL 0.67 l/min/m2and 3.54 pL 0.35 kPa, respectively, remained at the same low level throughout the study. In the six nontreated patients, there were no significant changes in ST depression, exercise PAWP, or exertional ventilation.Conclusion: Isosorbide dinitrate treatment markedly improved exercise‐induced left heart dysfunction, whereas excessive ventilatory response was unaffected, even after 3 h. Thus, measurements of the exercise hyperpnea did not properly reflect effective reduction of myocardial ischemia.
The role of flumazenil in outpatient transesophageal echocardiography
Authors: Tsang Teresa S. M. , Martin Marjorie L. , Bailey Kent R. , Seward James B. 
Published: February 2009

AbstractBackground: Benzodiazepines used for transesophageal echocardiography (TEE) sedation may be associated with postprocedural psychomotor effects that are undesirable.Hypothesis: We hypothesize that flumazenil can reverse cognitive and motor effects from benzodiazepine, promoting earlier return to baseline function.Methods: We prospectively evaluated the cognitive and motor function of patients who did or did not receive flumazenil following TEE. Patients' gait, level of drowsiness, and recall of items learned before and after benzodiazepine administration were evaluated before TEE, as well as immediately and 30 min after the procedure.Results: Of 207 patients (123 men and 84 women), 93 (45%) were given flumazenil 0.2 or 0.4 mg intravenously, and 113 (55%) were not. The baseline characteristics of the patients who received flumazenil were not significantly different from those who did not receive flumazenil, with the exception of a higher mean dosage of midazolam administered to the flumazenil group. In addition, patients in the flumazenil group appeared more drowsy immediately following TEE. When adjusted for age and midazolam dosage, there were no differences, at any time, between the two groups in gait or recall of items learned prior to sedation. However, at 30 min following TEE, the flumazenil group was able to recall a larger number of new items learned immediately after the procedure (1.92/3 vs. 1.61/3, p = 0.02) than did patients in the group not receiving flumazenil. No adverse effects were encountered in any patient.Conclusion: Flumazenil appears safe and effective in reversing anterograde amnesic effects of benzodiazepine following TEE, but has no effects on retrograde amnesia and does not promote earlier return of motor function to baseline. It is useful in clinical situations where high dosages of benzodiazepine have been used and/or excessive drowsiness is evident following TEE. Routine use of the drug, however, is not necessary.
The clinical utility of adenosine in difficult to diagnose tachyarrhythmias
Authors: O'Rourke Daniel J. , Palac Robert T. , Schindler John T. , Keim Stephen G. 
Published: February 2009

AbstractBackground: The use of intravenous adenosine to help differentiate the origin of tachyarrhythmias has been suggested to be beneficial. However, the benefit of this intervention to physicians with different levels of training in electrocardiographic (ECG) interpretation is unknown.Hypothesis: The purpose of the study was to determine whether intravenous adenosine improved the diagnostic accuracy of difficult to diagnose tachyarrhythmias when used by physicians with different levels of training in ECG interpretation.Methods: We studied 28 consecutive patients presenting with wide and narrow complex tachyarrhythmias, in whom adenosine was given specifically for diagnostic purposes. Two groups of physicians, attending (n = 14) and housestaff (n = 10), reviewed each ECG before and after the administration of adenosine.Results: For narrow complex tachyarrhythmias, neither physician group derived diagnostic benefit from the use of adenosine. However, for wide complex tachyarrhythmias, the diagnostic accuracy of the housestaff group significantly improved with the use of adenosine (pre = 54%, post = 70%, p < 0.01), while the attending physician group had no significant improvement (pre = 61%, post = 71%, p = NS).Conclusion: This study suggests that adenosine provides useful diagnostic information to physicians less experienced in ECG interpretation when presented with patients having wide complex tachyarrhythmias of uncertain origin.