bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nonfebrile Illness Seizures: A Unique Seizure Category?
Authors: Zerr Danielle M. , Blume Heidi K. , Berg Anne T. , Del Beccaro Mark A. , Gospe Sidney M. , Allpress Amanda L. , Christakis Dimitri A. 
Published: June 2005

Summary:  Purpose. To describe the clinical characteristics of children with a first‐time nonfebrile seizure in the setting of mild illness and to test the hypothesis that these seizures are associated with illness characterized by diarrhea. Methods. This retrospective cohort study was performed in a pediatric emergency department. Patients ages 6 months to 6 years who were evaluated with first‐time seizures were eligible for inclusion. Subjects were divided into three groups on the basis of symptoms accompanying their seizure: febrile (temperature, >38.0°C with seizure), unprovoked (no symptoms of illness), and nonfebrile illness (no fever at the time of seizure, but other symptoms of illness present). Results. Of the 323 children with first‐time seizures, 247 (76%) had febrile seizure, 37 (12%) had unprovoked seizures, and 39 (12%) had nonfebrile illness seizures. Children with nonfebrile illness seizures were more likely than children with febrile seizures to have diarrheal illnesses accompanying their seizure (44 vs. 16%; p = 0.001). Frequency of cough, rhinorrhea, and rash did not differ significantly between children with febrile and nonfebrile illness seizures. Diagnostic testing for infectious etiologies was not performed frequently in either group. Conclusions. Nonfebrile illness seizures may represent a distinct group of seizures with unique epidemiology. Further study to define this seizure group better is warranted.
Anticonvulsant Properties of the Novel Nootropic Agent Nefiracetam in Seizure Models of Mice and Rats
Authors: Kitano Yutaka , Komiyama Chika , Makino Mitsuhiro , Takasuna Kiyoshi , Takazawa Akira , Sakurada Shinobu 
Published: June 2005

Summary: Purpose:Nefiracetam (NEF) is a novel pyrrolidone‐type nootropic agent, and it has been reported to possess various pharmacologic effects as well as cognition‐enhancing effects. The present study focused on the anticonvulsant effect of NEF and its potential for antiepileptic therapy.Methods:The anticonvulsant properties of NEF were investigated in experimental seizure models of mice and rats, compared with levetiracetam (LEV) and other standard antiepileptic drugs [AEDs; zonisamide (ZNS), phenytoin (PHT), carbamazepine (CBZ), valproic acid (VPA), diazepam (DZP), and ethosuximide (ESM)]. With reference to standard programs for evaluating potential AEDs, the study included the traditional maximal electroshock seizure and subcutaneous chemoconvulsant (pentylenetetrazole, bicuculline, picrotoxin, strychnine, orN‐methyl‐d‐aspartate) seizure tests and two threshold models (the increasing‐current electroshock seizure test and intravenous pentylenetetrazole seizure threshold test). Neurotoxic activities were examined with the rotarod test and traction test.Results:NEF inhibited electroshock‐induced seizures at nontoxic doses, whereas it had no effect on seizures chemically induced by pentylenetetrazole, bicuculline, picrotoxin, strychnine, orN‐methyl‐d‐aspartate. The anticonvulsant spectrum of NEF paralleled that of ZNS, PHT, and CBZ. The anticonvulsant efficacy of NEF was comparable with that of ZNS and less potent than that of PHT, CBZ, and DZP. However, the safety margin of NEF was superior to that of ZNS, CBZ, VPA, and DZP. LEV showed only slight anticonvulsant effects in threshold models, and it was not effective in conventional screening models.Conclusions:These results suggest that NEF has distinct anticonvulsant spectrum and mechanisms from those of LEV. NEF is an orally active and safe AED, and it possesses a potential for antiepileptic therapy.
Localization of Breast Cancer Resistance Protein (BCRP) in Microvessel Endothelium of Human Control and Epileptic Brain
Authors: Aronica Eleonora , Gorter Jan A. , Redeker Sandra , Van Vliet Erwin A. , Ramkema Marja , Scheffer George L. , Scheper Rik J. , Van Der Valk Paul , Leenstra Sieger , Baayen Johannes C. , Spliet Wim G. M. , Troost Dirk 
Published: June 2005

Summary:  Purpose: Breast cancer resistance protein (BCRP) is a half adenosine triphosphate (ATP)‐binding cassette (ABC) transporter expressed on cellular membranes and included in the group of multidrug resistant (MDR)‐related proteins. Recently, upregulation of different MDR proteins has been shown in human epilepsy‐associated conditions. This study investigated the expression and cellular distribution of BCRP in human control and epileptic brain, including a large number of both neoplastic and nonneoplastic specimens from patients with chronic pharmacoresistant epilepsy. Methods: Several epileptogenic pathologies, such as hippocampal sclerosis (HS), focal cortical dysplasia (FCD), dysembryoplastic neuroepithelial tumor, oligodendroglioma astrocytoma, and glioblastoma multiforme were studied by using Western blot and immunocytochemistry. Results: With Western blot, we could demonstrate the presence of BCRP in both normal and epileptic human brain tissue. In contrast to P‐glycoprotein (P‐gp) and multidrug resistance–associated protein (MRP) 2, BCRP expression levels did not change in tissue from patients with HS, compared with control hippocampus. No BCRP immunoreactivity was observed in glial or neuronal cells, including reactive astrocytes and dysplastic neurons in FCD. BCRP expression was, however, increased in tumor brain tissue. Immunocytochemistry demonstrated that BCRP was exclusively located in blood vessels and was highly expressed at the luminal cell surface and in newly formed tumor capillaries. This localization closely resembles that of P‐gp. The higher expression observed in astrocytomas by Western blot analysis was related to the higher vascular density within the tumor tissue. Conclusions: These results indicate a constitutive expression of BCRP in human endothelial cells, representing an important barrier against drug access to the brain. In particular, the strong BCRP expression in the microvasculature of epileptogenic brain tumors could critically influence the bioavailability of drugs within the tumor and contribute to pharmacoresistance.
Successful Initiation of Combined Therapy with Valproate Sodium Injection and Divalproex Sodium Extended‐release Tablets in the Epilepsy Monitoring Unit
Authors: Boggs Jane G. , Preis Keith 
Published: June 2005

Summary:  Purpose: Patients in epilepsy monitoring units (EMUs) often require aggressive initiation or reinitiation of therapy before discharge. We developed a simple dosing scheme using valproate sodium injection (VPA‐IV) and divalproex sodium extended‐release (VPA‐ER) tablets to minimize the time required for initiation of therapy, without increasing the likelihood of seizures and adverse effects. Methods: We identified 42 patients in the EMU, naïve to VPA‐IV and VPA‐ER, for whom one of the discharge AEDs included divalproex sodium. On the day of discharge, patients were loaded with 20 mg/kg VPA‐IV at 6 mg/kg/min, followed by ∼20 mg/kg VPA‐ER within 1 h. The discharge daily dose of VPA‐ER was identical to the dose given after the IV load. We assessed tolerability and seizure occurrence during infusion, at 1 h, 4 h, and 1 week after discharge. Results: All patients tolerated the VPA‐IV dose followed by VPA‐ER. Four patients reported mild nausea, and two patients reported mild dizziness within 4 h. No seizures or significant changes in heart rate or blood pressure occurred within 4 h, and all patients were discharged the same day. All patients denied systemic complaints at 1 week, and five had seizures during the week after discharge. All patients had improved seizure frequencies at the end of the first week. Conclusions: VPA‐IV is well tolerated and convenient for rapid loading in the EMU. When promptly followed by VPA‐ER, seizure control remains excellent.
Brain Perfusion Assessed by 99mTc‐ECD SPECT Imaging in Pediatric Patients with Neurally Mediated Reflex Syncope
Authors: İLGIN N. , OLGUNTURK† R. , KULA† S. , TURAN† L. , TUNAOĞLU† S. , TEMIZ H. , GOKCORA N. , GÜCÜYENER† K. 
Published: June 2005

Background: The involvement of cardiogenic and neurogenic mechanisms in neurally mediated reflex syncope is well documented. In our previous studies in patients with neurally mediated reflex syncope, we have found evidence for differential regulation of the noradrenergic receptors in tilt‐positive and tilt‐negative patients. The present work concentrates on the observations of differences in regional brain perfusion using brain SPECT via injecting the patient at the completion of the tilt test.
Methods and Results: The following study was designed to assess the reduction and regional differences in cerebral blood flow by means of SPECT using technetium‐99m labeled V‐oxo‐1,2‐N1ethylenedylbisl‐cysteine diethylester (ECD) in patients with an injection during tilt testing. Twenty patients with NMS were included in the study with a mean age of 12.2 years (age range; 8–16 years). HUT was positive in 10 patients and negative in 10 patients. When tilt (+) and tilt (−) were evaluated together, regional cortical/cerebellum ratios were ranging from 0.85 to 1.25 in different cortical areas with highest variability of perfusion index in left frontoparietal cortex. The lowest perfusion index values were observed in the left anterior frontal region followed by the left prefrontal‐frontoparietal‐anterior, parietal‐orbito frontal, and anterior temporal regions where perfusion is predominantly supplied via the anterior and middle cerebral arteries, while these differences did not reach statistical significance in a single dominant region compared to the other regions examined using ANOVA (P > 0.05) with this sample size.
Decreases in [99mTc]ECD uptake were more widespread regionally on the left hemisphere than were decreases in right side of the brain. However when tilt– and tilt+ groups were compared, perfusion was significantly lower in the right periinsular posterior parietal and temporal regions (P < 0.05) in tilt + group.
Conclusion: These tilt induced regional differences in brain perfusion suggest the distinct roles of middle cerebral artery dominant territory‐related vasodepressor compensation mechanisms in neurally mediated reflex syncope phenomena where cerebral lateralization of cardiac control and insular ischemia may play an important role.
Effect of Inter‐electrode Distance on Bipolar Intramural Radiofrequency Ablation
Authors: KOVOOR PRAMESH , DALY MICHAEL , POULIOPOULOS JIM , DEWSNAP M. BARBARA , EIPPER VICKI , ROSS DAVID L. 
Published: June 2005

Objectives: We aimed at evaluating bipolar radiofrequency ablation by correlating inter‐electrode distance (ILD) with lesion dimensions and continuity.
Background: Previous reports indicated that bipolar radiofrequency (RF) current applied to two adjacent sites in vitro, synergistically increased lesion sizes greater than that observed for unipolar RF current delivery using the same electrodes.
Methods: Ablations were performed intramurally to ensure that each electrode surface (radius = 0.4 mm, area = 3.52 mm2) provided consistent contact with the myocardium. Ninety‐six ablations were performed in four greyhounds using bipolar ablation needles with ILDs of 1, 2, 3, and 4 mm. An epicardial approach was used to ensure accurate positioning of the needles within the myocardium. Lesions were created using temperature‐controlled RF delivery for a duration of 60 seconds to achieve 90°C at the electrode proximal to the needle base. Lesion dimensions were determined histologically.
Results: Increasing the ILD, decreased lesion width (P = 0.003) but increased lesion depth (P = 0.001). Lesions remained continuous with ILDs of 1–3 mm but became discontinuous at 4 mm. Energy requirements during ablation increased with increasing ILDs.
Conclusion: Using the above parameters (electrode radius, RF power delivery, time) during bipolar ablation, lesion continuity was critically dependent on the ILD. The maximum ILD threshold to create contiguous overlapping lesions was 3 mm. Lesions of greater width were created using shorter ILDs. Clinically, greater control over lesion dimensions can be obtained by manipulating the ILD distance.
Cross‐Ventricular Pacemaker‐Mediated Tachycardia by Myopotential Induction during Biventricular Pacing
Authors: GUENOUN MAXIME , HERO MARC , ROUX OLIVIER , MAINARDIS MARC 
Published: June 2005

Background: Patients in permanent atrial fibrillation treated for heart failure and ventricular asynchrony can be implanted with conventional dual chamber pacemakers (DDD) pacemakers used in the biventricular mode. The left ventricular lead is connected to the atrial channel.
Case Report: We report the case of a patient who developed ventriculo‐ventricular pacemaker‐mediated tachycardia (PMT) induced by myopotential sensing in the atrial channel, inhibiting left ventricular pacing.
Conclusion: In the absence of specifically designed pacemakers, the use of DDD pacemakers in the biventricular mode requires certain precautions, such as anti‐PMT mode activation, disabling automatic sensitivity, and lengthening the postventricular atrial refractory period (PVARP), or mode switch to DVIR.
Pacing‐Induced Electrophysiological Remodeling in Hypertrophic Obstructive Cardiomyopathy—Observations on Cardiac Memory
Authors: NOWINSKI KAROLINA , WECKE LILIANE , GADLER FREDRIK , LINDE CECILIA , BERGFELDT LENNART 
Published: June 2005

Background: Hypertrophic cardiomyopathy carries an increased risk for sudden cardiac death. While pacing therapy reduces the left ventricular outflow tract gradient and improves symptoms in a subgroup of hypertrophic obstructive cardiomyopathy (HOCM) patients, its electrophysiological consequences are unknown and were therefore assessed in this prospective study.
Methods and Results: Fifteen consecutive HOCM patients were studied and compared with 14 patients without HOCM paced because of sinus bradycardia. ECG intervals were measured before pacemaker implantation and after ≥3 months of DDD pacing in HOCM patients and ≥5 weeks in controls. Both groups showed similar ECG signs of cardiac memory development. In HOCM patients, with baseline QTc 447 ± 33 ms, cardiac memory development was not associated with any significant changes in ECG intervals. In contrast, baseline repolarization in control patients was significantly prolonged by 6% (QTc 429 ± 33 vs 454 ± 46 ms; P < 0.05). Furthermore, in HOCM patients repolarization was 7% shorter during DDD pacing compared to sinus rhythm (JTc 329 ± 25 vs 353 ± 21 ms; P < 0.05), despite a significantly prolonged ventricular activation time (QRS duration 155 ± 16 vs 91 ± 9 ms; P < 0.01).
Conclusions: Importantly, the development of cardiac memory‐induced different repolarization responses depending on baseline structure and electrophysiology. In HOCM patients repolarization was shorter during right ventricular apical pacing than during normal activation despite prolonged activation time.
Reduction of Right Ventricular Pacing in Patients with Sinus Node Dysfunction Using an Enhanced Search AV Algorithm
Authors: MELZER CHRISTOPH , SOWELAM SAMEH , SHELDON TODD J. , BONDKE H.J. , BAUMANN GERT , COMBS BILL , THERES HEINZ 
Published: June 2005

Background: Dual chamber pacing typically results in a high percentage of ventricular pacing. A number of studies have been conducted suggesting detrimental effects of ventricular desynchronization produced by long‐term RV pacing. Pacemaker algorithms that extend the AV interval to uncover intrinsic AV conduction have been utilized to reduce ventricular pacing. These algorithms are often limited to AV intervals below 250 ms limiting the ventricular pacing reduction. We hypothesized that by allowing AV intervals to extend beyond 300 ms, a marked reduction in RV pacing can be achieved.
Methods: A total of 30 patients (17 men, mean age 71 ± 9) with standard Brady indications, and implanted with a Medtronic Kappa 700 pacemaker, were randomized to 2‐week treatments with default Search AV (KSAV) parameters or Enhanced Search AV (ESAV) parameters. The Enhanced Search AV algorithm included the capability for continuous adjustment of AV delays and the ability to auto disable in patients with persistent AV block.
Results: Among patients with intact AV conduction, percent VP was greater in KSAV versus ESAV (70 ± 40% vs 19 ± 28%, P < 0.001). In patients with persistent AV block, the algorithm suspended appropriately and there was no significant change in the percent VP between both arms of the study. In 18/22 patients, percent VP was reduced below 40%.
Conclusions: Substantial reduction in ventricular pacing can be achieved by allowing the AV interval parameters to extend beyond 300 ms using the ESAV algorithm. In patients with AV block, ESAV suspended and patients were paced at their nominal settings.
Development of Implantable Devices for Continuous Ambulatory Monitoring of Central Hemodynamic Values in Heart Failure Patients
Authors: BENNETT TOM , KJELLSTROM BARBRO , TAEPKE ROBERT , RYDEN LARS ,   for the Implantable Hemodynamic Monitor Investigators
Published: June 2005

Background: Care and management of patients with congestive heart failure (CHF) is a major health‐care challenge. The value of acute hemodynamic data in assessing heart failure has been questioned in some studies, while more intensive hemodynamic monitoring has been reported to improve patient care in others. A series of patient studies are reported here that were conducted to identify device requirements and verify the feasibility of continuous hemodynamic monitoring in CHF patients and devices for remote transfer and use of these data.
Methods and Results: The results of four separate studies in 68 CHF patients who received systems for chronic hemodynamic monitoring between 1992 and the present are reviewed. One early study was with five patients followed for 7–16 months and another study was with nine patients followed for 4–22 months. A third study included 21 patients followed up to 39 months, and the fourth study included 32 patients implanted in 1998–99 with many of them still in follow‐up. These studies support the technical feasibility of implanted devices and the external instrumentation required to transfer and manage the collected data. They also support the long‐term stability and accuracy of these systems. Three additional acute studies conducted with 30 patients and chronic data from 53 of the 68 patients with the implanted systems are presented that support the feature included in the newer monitors – the ability to reliably estimate pulmonary artery diastolic pressures from the right ventricular pressure signal.
Conclusions: Development of implantable technology to measure several hemodynamic variables in ambulatory CHF patients is feasible. External instrumentation needed to remotely acquire data from the implanted devices has been verified. The potential to eliminate the uncertainties associated with the use of acute, invasive hemodynamics and the ability to evaluate long‐term ambulatory hemodynamic patterns is provided. These findings set the stage for determining the potential clinical value of these systems in impacting the care of chronic CHF patients.
Left Ventricular Lead Performance in Cardiac Resynchronization Therapy: Impact of Lead Localization and Complications
Authors: ALBERTSEN ANDI EIE , NIELSEN JENS COSEDIS , PEDERSEN ANDERS KIRSTEIN , HANSEN PETER STEEN , JENSEN HENRIK KJÆRULF , MORTENSEN PETER THOMAS 
Published: June 2005

Introduction: Cardiac resynchronization therapy (CRT) using left ventricular (LV) pacing from the coronary sinus tributary is increasingly and frequently used in patients with severe congestive heart failure. The present study investigates LV lead performance in different anatomic locations.
Methods: The LV pacing site was defined by bi‐plane fluoroscopy. In the left anterior oblique view, the coronary sinus is encircling the mitral ring with the tributaries radiating out like the hands of a watch. Using this clockwise method, Group A had an LV pacing site before 3 o'clock and Group B at or after 3 o'clock. In right anterior oblique view, the LV was divided into three segments: basal, mid‐ventricular, and apical.
Results: LV lead implantation was successful in all of 120 consecutive patients. Mean follow‐up was 16.7 months. Implantation time decreased from mean 190 to 80 minutes during the period (P = 0.01). The mean LV lead stimulation threshold increased initially and stabilized afterwards. The threshold measured at last follow‐up was higher than at implantation (2.3 vs 2.7 μJ, P = 0.04). Useful venograms were obtained in 94 patients. No significant difference in thresholds was observed between Groups A and B. Phrenic nerve stimulation was most commonly seen in Group B (8/70 vs 1/24, P = 0.001).
Conclusion: Implantation of an LV lead for CRT is possible in patients with congestive heart failure and associated with an acceptable low complication rate. LV lead implantation is associated with a learning curve. At mid‐term follow‐up, LV lead performance is stable and unrelated to the LV implantation site.
Electrogram Configuration and Detection of Supraventricular Tachycardias by a Morphology Discrimination Algorithm in Single Chamber ICDs
Authors: LÜTHJE L. , VOLLMANN D. , ROSENFELD M. , UNTERBERG‐BUCHWALD C. 
Published: June 2005

Background: Inappropriate ICD therapy for supraventricular tachycardia (SVT) remains a significant problem. A morphology‐based algorithm (Wavelet™) compares baseline and tachycardia electrograms (EGM). For this analysis different EGM sources can be programmed. This study evaluates the performance of Wavelet using two different EGM configurations (SVC‐Can and RV‐Can) for the detection of exercise‐induced SVT.
Methods: Patients with a Medtronic model 7230 single chamber ICD and a dual coil lead were included. For each EGM source (SVC‐Can or RV‐Can), a baseline EGM template was acquired and the morphology similarity to this template (match percentage) was evaluated for 10–15 beats at different heart rates during exercise testing. The lower VT detection limit was programmed to 600 ms (therapies off).
Results: A total of 28 patients (66.9 ± 4.7 years, 93% men) and 5,824 intracardiac QRS complexes were analyzed. With the RV‐Can source, a consistently high similarity to the baseline EGM template was observed (≤100 bpm: 90.90 ± 0.56%; >100 bpm: 90.24 ± 0.55%, P > 0.05). In contrast, SVC‐Can was associated with a lower match percentage at baseline and a significant decrease at higher heart rates (≤100 bpm: 77.91 ± 2.65%; >100 bpm: 59.05 ± 5.65%, P < 0.005). Accordingly, the specificity for appropriate detection of exercise‐induced SVT was higher with RV‐Can (21/21 episodes) than with SVC‐Can (8/18 episodes, specificity 100% vs 44%; P < 0.0001).
Conclusion: The RV‐Can configuration appears to be superior to SVC‐Can as EGM source for appropriate SVT detection with the Wavelet algorithm.
Pregnancy in Postural Orthostatic Tachycardia Syndrome
Authors: GLATTER KATHRYN A. , TUTEJA DIPIKA , CHIAMVIMONVAT NIPAVAN , HAMDAN MOHAMED , PARK JEANNY K. 
Published: June 2005

Introduction: Postural orthostatic tachycardia syndrome (POTS) is a rare disease characterized by syncope, sinus tachycardia, and orthostasis due to autonomic dysfunction.
Methods and Results: Two women aged 26 and 24 years with severe POTS became pregnant. Both women experienced hyperemesis gravidarum with subsequent marked improvement in their POTS symptoms until 6 months gestation, when their syncope and sinus tachycardia caused clinical decompensation. Both patients delivered healthy babies at 37 weeks by elective cesarian section.
Conclusion: In long‐term follow‐up, both women reported improvement in their prepartum symptoms. We describe the first report, to our knowledge, of two successful pregnancy outcomes in severe POTS, including the first report of midodrine use in pregnant women.