bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of clinical features of acute pancreatitis in Shandong Province, China
Authors: Gao Yan Jing , Li Yan Qing , Wang Qing , Li Shen Lin , Li Guo Qing , Ma Ji , Zeng Xian Zhong , Huang Liu Ye , Yuan Sheng An , Liu Chun An , Wang Fu Xian 
Published: July 2006

AbstractAim:  To investigate and obtain a more comprehensive view of the etiology and clinical features of acute pancreatitis in China.Method:  The study comprised 1471 patients in 10 cites of China who were admitted to hospitals for acute pancreatitis from January 1992 to December 2002. Data for each patient were collected on a standardized form.Results:  Of the 1471 patients (854 men, 617 women; mean age 43.3 years; range 13–82 years), 1280 had mild pancreatitis and 191 had the severe form. Cholelithiasis (20.2%), alcohol (17.3%) and diet‐induced (12.4%) were the most frequent etiological factors, followed by biliary tract infections (5.6%), hyperlipidemia (2.3%) and other factors (5.1%). However, in about 36.1% of cases, the etiology of acute pancreatitis still remained unexplained. In coastal regions, cholelithiasis was the most frequent factor but alcohol ranked first in interior regions. In males, a small predominance of alcohol over cholelithiasis was seen (27.4%vs 14.3%) and there was a clear predominance of cholelithiasis over alcohol (28.4%vs 3.2%) in females. The differences in the frequency of cholelithiasis and alcohol between coastal regions and interior regions and males and females were statistically significant (P < 0.01). According to their frequency, complications of acute pancreatitis were pancreatic pseudocyst, pancreatic ascities and bacterial peritonitis, pulmonary infections, multiple organ failure, diabetes mellitus type 2 and shock.Conclusion:  Cholelithiasis, alcohol and diet‐induced factors were the main etiological factors seen in China, whereas cholelithiasis alone predominated in females and alcohol ranked first in males. In about 36.1% of cases, the etiology of acute pancreatitis remained unknown. More attention should be paid to studying the etiologies of acute pancreatitis that remain unknown.
Determination of mutations of the 23S rRNA gene of Helicobacter pylori by allele specific primer‐polymerase chain reaction method
Authors: Nakamura Akiko , Furuta Takahisa , Shirai Naohito , Sugimoto Mitsushige , Kajimura Masayoshi , Soya Yoshihiro , Hishida Akira 
Published: July 2006

AbstractBackground and Aims:  Susceptibility to clarithromycin of Helicobacter pylori (H. pylori) is caused by single nucleotide polymorphisms (SNPs) of the 23SrRNA gene. Allele specific primer‐polymerase chain reaction (ASP‐PCR) is one of the methods for determining SNPs, which can measure SNPs easily within a short period by PCR amplification alone without digestion with restriction enzymes. The aim of the present study was to develop the ASP‐PCR assay for determining SNPs at positions 2142 and 2143 of the 23S rRNA gene of H. pylori.Methods:  In total, 112 patients with H. pylori infection based on positive results of a rapid urease test (RUT) were enrolled in the study. Thirty‐five had failed to eradicate H. pylori by a clarithromycin‐based regimen. DNA was extracted from the RUT‐positive gastric tissue samples. SNPs from adenine to guanine at positions 2142 and 2143 of the 23S rRNA of H. pylori (A2142G and A2143G) were determined by the ASP‐PCR method. Minimum inhibitory concentrations (MICs) of clarithromycin for H. pylori were also measured.Results:  Forty‐nine of 112 patients were infected with wild‐type strains of H. pylori. Thirty‐nine patients were infected with strains with A2143G mutations. Twenty‐three patients were infected with both wild‐type strains and those with A2143G mutations. Only one patient was infected with the strain with A2142G mutation. H. pylori strains with A2143G or A2142G mutation had significantly higher MICs for clarithromycin.Conclusion:  The ASP‐PCR assay for 23S rRNA mutation of H. pylori is a useful method to detect clarithromycin‐resistant strains of H. pylori easily.
Clinical Value of Tests of Sino‐Atrial Function*
Authors: EVANS T.R. , CALLOWHILL E.A. , KRIKLER D.M. 
Published: July 2006

Sinus node recovery times and the premature atrial stimulus test were studied in 36 patients, seven with gross sinus node disease, 25 with possible sinus node disease and four with no clinical evidence of sinus node disease. The corrected sinus node recovery time proved of most value in predicting which patients needed and would benefit from permanent pacemaker implantation, though there was one false negative diagnosis and two patients with abnormal corrected sinus node recovery times were asymptomatic. The premature atrial stimulus test usually proved to be of no practical value once severe sinus node disease was present and, in the group of patients with suspected sino‐atrial disease, only 13 of 25 graphs could be analysed due to gross “scatter” in the others.When patients with symptoms have unequivocal evidence of sino‐atrial dysfunction, invasive study seems unnecessary. With lesser degrees of sino‐atrial disease, premature atrial stimulation may provide confirmatory evidence; but when sinus arrhythmia, atrial escape beats, or more marked dysfunction are present, one is likely to encounter useless “scatter” graphs. In the absence of regular sinus rhythm on the EGG, overdrive sinus node suppression is the only invasive study worth attempting.
Hemodynamic Consequences of Atrioventricular and Ventriculoatrial Pacing
Authors: OGAWA SATOSHI , DREIFUS LEONARD S. , SHENOY PRAKASH N. , BROCKMAN STANLEY K. , BERKOVITS BAROUH V. 
Published: July 2006

The effect of atrialventricular versus ventricular pacing and contraction were studied in seven open‐chest dogs. Cardiac output, left ventricular, left atrial, right atrial and pulmonary artery pressures were recorded. The right or left ventricular apical areas were consistently superior as ventricular pacing sites.Appearance of cannon A waves within the pre‐ or ejection period produced a significant decrease in left ventricular and systemic blood pressure, and cardiac output with a concomitant increase in right atrial, ventricular and pulmonary pressures. Prominent “v” waves were also observed during these periods.Reducing the basic driving cycle length from 400 to 300 msec caused a marlted deterioration of all hemodynamic parameters with the appearance of mechanical alternans. Random VA conduction or ventricular pacing in the presence of com‐plete AV and VA heart block appeared to offer a more favorable hemodynamic result than constant 1:1 VA conduction. It is concluded that maintenance of a physiologic AV interval permitting atrial contraction to appear outside of pre‐ or ejection period of ventricular systole is an important determinant or ventriculor function during cardiac pacing.
Influence of Output Capacitor, Electrode and Pulse Width on Power Consumption in Cardiac Pacing‡
Authors: EDHAG OLOF , LAGERGREN HANS , THORÉN ANDERS , WAHLBERG INGER 
Published: July 2006

Three different types of unipolar endocardial electrodes—47 in all—were compared in regard to power consumption at stimulation threshold with six different output capacitors and seven pulse widths.Fifteen were conventional large surface electrodes (area 47 mm2); 18 were conventional small surface electrodes (area 6 mm2), and 14 had a specially designed tip with a large area but small active surface of 8 mm2. Pulse widths ranged from 0.15 to 2.0 msec and output capacitors from 1.0 to 22.0 4mUFarads. All in all about 2,000 measurements were performed. The average current drain to the pacemaker output stage was measured and power consumption was calculated for each electrode— pulse width—output capacitor combination. In all combinations, the two small surface electrodes consumed approximately the same amount of power and, in both cases, significantly less than the larger one.With regard to power economy at stimulation threshold, the pulse width of choice was about 0.5 msec and, furthermore, power consumption decreased with increasing capacitor size. The optimal combination was a small surface electrode, an output capacitor of 22 pF and a pulse width of 0.5 msec.
Permanent Cardiac Pacing with Electrodes of a New Type of Fixation in the Endocardium
Authors: BREDIKIS JURGIS , DUMCIUS ARIMANTAS , STIRBYS PETRAS , MUCKUS KAZIMIERAS , VETEIKIS ROMUALDAS , KOROLIOV VLADIMIR , YARMILKO PIOTR 
Published: July 2006

To improve electrode construction the following main problems have been considered: (1) reliable initial fixing in the endocardium, and (2) reducing the area of contact surface and improving threshold values.In this article we have described three original electrodes: (1) an endocardial electrode with a multi‐edged tip (contact area 28 mm2), which gives high electric field strength and low thresholds; 2) a spreading tip electrode, which was created on the basis of morphological data. The tissues grow into the spread spaces of this tip and ensure better stability fcontact area 17.8 mm2); and 3) a double‐screw‐in electrode which differs from the other corkscrew types. The contact end (surface area‐10,4 mm2) consists of two sickle‐shaped hooks. The sickle handle is 0.7 mm in length which prevents further hook penetration in the wall of the heart.It was found that a multi‐edged electrode and electrodes supplied with a fixation device are, in terms of energy consumption, more effective compared to electrodes with spherical or cylindrical tips of the same area of contact surface.The double‐screw‐in endocardial electrode has useful features: reliable fixation and a small contact surface area and, therefore, a low threshold value. Thirty‐five double‐screw‐in electrodes were inserted into an atrial position and 28 into a ventricular position. We have not observed any displacement of such electrodes during the past two years.
Unusual Electrocardiographic Pattern During Transvenous Pacing From the Middle Cardiac Vein
Authors: BAROLD S. SERGE , BANNER RICHARD 
Published: July 2006

This report documents the unusual occurrence of a left bundle branch block pattern of ventricular depolarization during permanent pacing from the middle cardiac vein. All previous reports of ventricular pacing from the middle cardiac vein have described a right bundle branch block pattern of ventricular activation (dominant R‐waves in the right precordial leads), except in one case where both right and left bundle branch block patterns occurred at separate times.A high posterior infarct allowed early activation of the right ventricle from the middle cardiac vein. Undue reliance on the electrocardiogram may detract from the diagnosis of electrode malposition.
Self‐Conversion of Supraventricular Tachycardia by Rapid Atrial Pacing*
Authors: WAXMAN MENASHE B. , WALD ROBERT W. , BONET JORGE F. , MACGREGOR DAVID C. , GOLDMAN BERNARD S. 
Published: July 2006

The use of pacemakers in the treatment of tachycardias is one of the most exciting and rapidly expanding applications of cardiac pacing. One of the more recent developments in this field has been the use of patient‐activated radio frequency transmitted rapid atrial stimulation (RAS) in the treatment of paroxysmal supra‐ventricular tachycardia (PSVT). Based on the previously established ability of asynchronous atrial pacing to interrupt a variety of re‐entrant supraventricular rhythm disturbances, this modality of treatment is gaining increasing applicability in patients with PSVT associated with debilitating symptoms or other severe cardiovascular consequences in whom standard pharmacological regimens have either failed or are impossible to maintain for indefinite periods.This report describes our experience with five patients who underwent implantation of HAS units. The detailed electrophysiological studies required to ensure success and avoid any possible future complications are described. Over a follow‐up period of four months to four years (mean 16 months) very few problems arose in the use of these units which have immeasurably improved the quality of life of the recipients. Our experience with RAS units has led to a few suggestions for future improvement and these are outlined in this report.The excellent patient acceptance and the reliability of this technique in terminating episodes of PSVT should, in the future, render RAS the treatment of choice in certain selected patients suffering form this common disorder.
Atrial Programmed Pacing*
Authors: SMYTH NICHOLAS P.D. 
Published: July 2006

Early experience with a J‐shaped lead inserted transvenously into the right atrial appendage is reviewed in thirty‐one patients. Fifteen patients are still being followed with satisfactory atrial programmed pacing for five to (en years. A dislodgement rate of twenty percent led to the development of the “lined” J lead in the hope that better fixation would be achieved.Experimental data has shown the new lead to be stable with evidence in both animal and man of firm fixation of the lead in the appendage. The lead has been inserted in twenty patients. Of these, fifteen are still being followed with satisfactory atrial programmed pacing. There has been no case of dislodgement of the lead in a follow‐up period of two years and eight months.
Transvenous Long‐Term Pacing with an External Pacemaker. What are the risks?
Authors: SIDDONS HAROLD 
Published: July 2006

Externalized endocardial electrodes were used for pacing 138 patients for periods of one month to 12 years. In the 416 patient/years of pacing by this method, 13 septicemias occurred.Implanted pacemakers with endocardial electrodes were used in 3186 patients. In the 3488 patient/years 13 septicemias occurred.The mortality and an assessment of the cause of death for pacing by the two methods is presented.It is concluded that the external method of transvenous pacing carries additional risk and is only justified in special circumstances.
Reciprocating Tachycardia Due to a Right‐Sided Unidirectional Retrograde Anomalous Pathway (URAP)*
Authors: ORZAN FULVIO , GILLETTE PAUL C. 
Published: July 2006

An 8 year‐old boy had extensive electrophysiological evaluation of his recurrent supraventricular tachycardias. His EGG never showed delta waves but intracardiac stimulation and recording disclosed the following: (1) eccentric retrograde atrial activation; (2) increased cycle length and retrograde conduction time following the development of right bundle‐branch block; (3) constant retrograde conduction time for increasingly premature ventricular stimuli; (4) atrial captures by ventricular stimuli when the atrioventricular‐His pathways were refractory; and (5) no delta waves upon stimulation of the atrial input site of the anomalous pathway. A diagnosis of reciprocating tachycardia involving retrograde conduction through an accessory pathway was made.Reciprocating tachycardias involving a unidirectional retrograde anomalous pathway can be easily misdiagnosed as atrioventricular node reentrant tachycardias if no evidence of preexcitation can be found, particularly if the anomalous pathway is on the right side. In order to exclude the participation of a concealed unidirectional anomalous pathway in a patient's reentry tachycardia, a complete map must be made of right and left atrial endocardial activity.
Unipolar Ventricular Electrogram in the Diagnosis of Right Ventricular Ischemic Injury
Authors: VARRIALE PHILIP , NIZNIK JOSEF 
Published: July 2006

Unipolar ventricular electrograms were recorded in the right ventricular apical area in five patients with clinical, hemodynamic features of the right ventricular infarction.The intracavitary potential exhibited a downward displacement of the ST segment (1.5 mV). This significant negative current of injury in the ventricular electro‐gram is consistent with ischemic injury of the free right ventricular wall in the area subtended by the intracavitary exploring electrode.We suggest that ventricular electrographic recordings be performed in patients who present with acute inferior wall infarction requiring temporary electrode catheter pacing for serious AV conduction disturbances. The presence of a significant downward ST segment displacement (1.5 mV) provides further support and an electrical criterion for right ventricular ischemic injury.unipolar, ventricular electrogram, endocardial potential, negative deflection, ischemic injury, right ventricular infarction
Spontaneous Termination of Reentry Ventricular Tachycardia in the Late Myocardial Infarction Period: An Experimental Study in the Dog
Authors: OGAWA SATOSHI , KAPLINSKY ELIESER , DREIFUS LEONARD S. 
Published: July 2006

Forty episodes of induced ventricular tachycardia in the late myocardial infarction period (4‐6 days old) were analyzed in 12 dogs in an attempt to identify the possible mechanisms for the termination of reentry tachycardia. Multiple epicardial and endocardial composite electrograms were recorded in and around the central ischemic zone of the infarction. During tachycardia, the earliest site of activation was identified in the epicardial surface of the border or normal zone immediately adjacent to the ischemic zone in 36 of the 40 episodes, suggesting efferent epicardial spread from the site of the activity. In four instances, the efferent pathways were directed to the endocardial surfaceFour distinct patterns of activation sequences were observed during spontaneous termination: (a) a shift of the efferent pathways from epicardial to endocardial site (19 instances); (b) a change of the efferent pathways within the endocardium (4 instances); (c) a shift of the earliest site of activation between the left arid right ventricles (9 instances); and (d) no apparent change in the epicardial efferent pathways (4 instances). In four other instances, ventricular tachycardia deteriorated into ventricular fibrillation. In patterns (a) and (c), a shift of the efferent pathways resulted in a more rapid and homogeneous activation of the border and normal zone epicardium. These changes were associated with cessation of delayed or continuous activity in the ischemic zone epicardium, resulting in termination of tachycardia. (PACE, Vol. 2, May‐June, 1979)
Beat‐to‐Beat Stability of Implanted Pacemakers
Authors: KRESH YASHA M. , PARSONNET VICTOR , MYERS GEORGE H. , PARSONNET BRIAN 
Published: July 2006

A method of measuring and analyzing beat‐to‐beat interval stability of implanted pacemakers has been devised, and a number of normal and failing pacers have been studied in this way. It was seen that normal pacer rates were remarkably stable, but that abnormalities in beat‐to‐beat interval were found in 67.4% of all failing pacers. The abnormalities consisted primarily of excessive interval (rate) scatter, linear and cyclic fluctuation, and transients following application of a magnet.It is expected that in problem cases a beat‐to‐beat analysis will be of help in differentiating normal from abnormal pacer function, and will provide confirmation signs of pacer failure; it may also uncover unusual and heretofore unpredictable failure modes. (PACE, Vol. 2, May‐June, 1979)
Radiation From Implantable Nuclear Pacemakers. II. Analysis
Authors: JACOBSON PETER M. 
Published: July 2006

SummaryThe dose equivalent rate from a nuclear pacer was determined in a previous paper10 through direct measurements of the gamma contribution, and through calculations of the neutron contribution which make use of computer simulation work done at the Oak Ridge National Laboratory. The resulting annual dose equivalent has been shown to be a level generally acceptable to adult individuals exposed for less pressing reasons than long‐term cardiac pacing, in a comparison with the maximum permissible dose (MPD). Other guide lines have been applied elsewhere, but are largely inappropriate. The MPD is a level expected to produce a vanishingly small risk for exposed individuals.
The Use of Balloon‐Tipped Electrodes for Permanent Cardiac Pacing
Authors: SLOMAN J. GRAEME , MONO HARRY G. , BAILEY BRIAN , COLE ANNETTE , DUFFIELD ANNE 
Published: July 2006

A new balloon‐tipped ventricular endocardial electrode for permanent artificial cardiac pacing is described. Following transvenous insertion of [he electrode to the right ventricular apex, the distal balloon is inflated with contrast material in order to wedge the electrode tip between or beneath trabeculae and prevent displacement. Fifty‐nine electrodes were implanted, including a second generation type incorporating a wedge tip as well as the balloon. The incidence of displacement was 17% with 10% of coses being early, and 7% late. Early in (he series, 5U Urogrofin was used to inflate the balloon and this resulted in premature deflation and early electrode displacement in two of the nine patients. When the concentration of Urografin was reduced, the balloon remained inflated for a longer period and the incidence of early displacement was reduced to 8%. However, there was still a late displacement of 8%, Only one wedge‐tipped balloon electrode displaced. This electrode had a faulty sealing mechanism and the balloon could not be adequately inflated. There was a 3% incidence of early and a 3% incidence of late threshold problems with the electrode. However, none of the wedge‐tipped balloon electrodes exhibited this problem.It was concluded that this new electrode did not fulfill its objectives. The total electrode failure rate, including displacements and episodes of high threshold was approximately 24%.
Mode of Operation Induced by Rapid External Chest Wall Stimulation in Patients with Normally Functioning QRS‐Inhibited (VVI) Pacemakers
Authors: CASTELLANOS AGUSTIN , BLOOM MARTIN G. , SUNG RUEY J. , ROZANSKI JOHN J. , MYERBURG ROBERT J. 
Published: July 2006

The effects of rapid external chest wall stimulation were evaluated in 10 patients with normally‐operating unipolar, lithium‐powered, QRS‐inhibited pacemakers functioning in their control VVI (QRS‐inbibtted) mode. Stimuli delivered at slow rates resulted in the expected pacemaker inhibition, On the other hand, during rapid (greater than 900/min) external chest wall stimulation, 8 pacemakers reverted to a VOO mode, 1 to a VVI mode and 1 to either a VVI or VOO mode. No pacemaker was totally inhibited by rapid chest wall stimulation. In accordance with the manufacturer's specifications, the rate to which the implanted pacemakers reverted during the VOO modes produced by the fast external stimuli were the same as those of the VOO modes induced by proper application of an external magnet. Although rapid external chest wall stimulation proved to be a safe procedure, more studies are necessary to determine its usefulness in the follow‐up of patients with implanted QRS‐inhibited (VVI) pacemakers, At present, conclusions cannot be drawn regarding whether these pacemakers will revert to a mode of operation similar to that induced by rapid external chest wall stimulation when subjected to extrinsic sources of strong electromagnetic interference. (PACE, Vol. 2, January‐February, W79)
Recurrent Pulmonary Emboli Secondary to Right Atrial Thrombus Around a Permanent Pacing Catheter: A Case Report and Review of the Literature
Authors: KINNEY EVLIN L. , ALLEN ROBERT P. , WEIDNER WILLIAM A. , PIERCE WILLIAM S. , LEAMAN DAVID M. , ZELIS ROBERT F. 
Published: July 2006

A case report and review of the literature.This report describes the management of a woman with multiple pulmonary emboli secondary to a large right atrial clot which had formed around her permanent trans‐venous pacemaker. She continued to have pulmonary emboli despite adequate anti‐coagulation. Removal of the catheter and pacing required right atriotomy under cover of cardiopulmonary bypass, Additionally, eight English language case reports of symptomatic pericatheter thromboses are reviewed. In these cases, pericatheter clot resulted either in right‐sided inlet obstruction or pulmonary emboJi. The mortality rate was 75%. Although the cause for our patient's thromboembolic events is uncertain, congestive heart failure was a predisposing factor in 75% of the other reported cases. We suggest that pacemaker patients in congestive heart failure might benefit greatly from chronic anticoagulation.