Search Results
Results 551 - 600 of 995
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Auricchio A - - 1993
Medical therapy often fails to control symptoms of severe heart failure. The possibility of modifying to some degree the global ventricular performance with the implantation of a physiological dual chamber pacemaker, set with a short atrioventricular delay (100 msec), has been adopted in two patients with severe heart failure due ...
Cooney W P - - 1993
Arthrography and arthroscopy of the wrist were compared as diagnostic tools in the evaluation of chronic wrist pain. Arthroscopy proved to be a more sensitive procedure than arthrography in 20 consecutive patients with confirmed wrist injuries. There was 86% correlation (the exception--one false negative arthroscopic procedure) between arthroscopy and arthrography ...
Persani L - - 1993
Circulating TSH bioactivity may vary in several clinical and experimental conditions. Since the reliability of the current methods for the measurement of TSH bioactivity is limited, a new bioassay based on cAMP accumulation in Chinese Hamster Ovary cells transfected with recombinant human TSH receptor (CHO-R) was set up. The sensitivity ...
Meloni L - - 1993
Miniaturized probes constitute recent progress in the field of epicardial echocardiography. We recently used a new miniaturized probe, derived from a standard transesophageal probe, in a series of 12 adult patients who underwent cardiac surgery in order to test the possibility of obtaining new views for epicardial imaging. This study ...
Storm C J - - 1993
Complete lead fracture is a uncommon phenomenon in cardiac pacing. Recently we encountered a patient with a severed lead at routine pacemaker follow-up visit. In this case report, the typical ECG changes and noninvasive pacemaker measurements are discussed. The chest roentgengram showed the position of the proximal part of the ...
Asroff S W - - 1993
A 75-year-old man with complete heart block and a ventricular demand pacemaker with the generator in a left upper-quadrant subcutaneous pouch underwent extracorporeal shock wave lithotripsy (SWL) for a 2-cm proximal right ureteral calculus, receiving 2000 shocks at 24 kV. There was no damage or malfunction of the pacemaker, and ...
Dickinson P S - - 1993
1. The cardiac sac network, which controls the rhythmic contractions of the cardiac sac in the foregut of crustaceans, is distributed throughout the stomatogastric nervous system, including the oesophageal ganglion (OG), the commissural ganglia (CGs), and the stomatogastric ganglion (STG). A red pigment-concentrating hormone (RPCH)-like peptide is likewise widely distributed. ...
Stroobandt R - - 1993
A new cause of pacemaker mediated tachycardia was observed in a patient equipped with a Vitatron Quintech 931 DDD pacemaker. In this type of pacemaker the microprocessor is switched off during the atrial refractory period. Beyond the recommended replacement time, the internal resistance of the battery may increase to such ...
Kreiner G - - 1993
The impact of a right bundle branch block (RBBB), inadvertently created prior to complete ablation of the atrioventricular (AV) junction, on the intrinsic subsidiary pacemaker function was investigated. In 31 patients suffering from intractable supraventricular tachyarrhythmia, catheter ablation of the AV junction was performed using direct current (n = 13) ...
Brown J R - - 1993
The study examines malathion aerosol cloud behavior in a North Florida pine flatwoods. Droplet mass median diameters (MMD) decreased over distance in both open and pine flatwoods. A sharp decrease in number of aerosol droplets per cm2 occurred between 3.1 and 15.2 m and a gradual decline in droplets per ...
Lammers W J - - 1993
The technique of multiple simultaneous recordings from a large number of extracellular electrodes (> 100) is currently used in the study of normal and abnormal electrical conduction in the heart and the genesis of cardiac arrhythmias. To investigate whether such a system could also be applied in gastrointestinal electrophysiology, several ...
Kuo K K - - 1993
When a patient has a pacemaker and requires operation, surgeons have to consider some possible intraoperative pacemaker complications induced by electrocautery. Electrocautery is commonly used during surgery to achieve hemostasis. However, this very effective tool may introduce innumerable problems in the paced patient, including irreversible damage to the pulse generator, ...
Refinetti R - - 1993
Cardiac contractions are under the influence of at least two processes of biological timing, one responsible for the mean level of heart rate (oscillations with a frequency of up to several hundred per minute) and another responsible for the circadian rhythm of heart rate (oscillations with a frequency of one ...
Hantson P - - 1993
A 61-year-old man without previous medical history was admitted for Guillain-Barré syndrome (GBS). Carbamazepine was prescribed on day 72 for dysesthesia occurring at the time of recovery. Subsequently, severe cardiac conduction disturbances (asystole, atrioventricular block) were observed and a permanent pacemaker had to be inserted. The possible relationship between carbamazepine ...
Yu H - - 1993
I(f), the "cardiac pacemaker current," is a nonselective cation channel activated on hyperpolarization in primary and secondary pacemaker regions of the mammalian heart. The cardiac pacing rate can be modulated by shifting the activation of I(f) to more positive (faster pacing) or more negative (slower pacing) voltages. We report for ...
Van den Bergh F - - 1993
In fibroblasts of severely retarded (type I) adenylosuccinase (ASase)-deficient children, activities with the two substrates of the enzyme, succinylaminoimidazole carboxamide ribotide (succinyl-AICAR) and adenylosuccinate are decreased in parallel, to about 30% of normal. In a markedly less retarded (type II) patient, ASase activity with adenylosuccinate reaches only 3% of normal, ...
Yu T J - - 1993
Acute urinary retention in two adolescent girls with hematometrocolpos caused by imperforate hymen are reported. The accumulation of the menstrual blood in the vagina and uterus may form a mechanical effect on the urethra and bladder and lead to the obstructive urinary symptoms. Hymenotomy created individually by CO2 laser and ...
Hay W P - - 1993
An extralaryngeal approach to partial arytenoidectomy in the horse was developed by in vitro experiments on isolated larynges and then on intact equine cadavers. The goals of the approach were to preserve the laryngeal mucosa, eliminate the need for a laryngotomy or tracheotomy, and minimize postoperative complications. The new approach ...
Sutton R - - 1993
The symptom most frequently requiring investigation and consideration for cardiac pacing is syncope. This symptom is now receiving more attention than ever, mainly because of the advent of tilt table testing--a simple noninvasive procedure that has substantially reduced the number of syncopal patients remaining undiagnosed. The first part of this ...
Shandling A H - - 1992
Chronic overdrive suppression pacing has been suggested as an effective adjunctive method for reducing the incidence of cardiac tachyarrhythmias. Documentation of effectiveness during prolonged monitoring is lacking, however. To assess more accurately the long-term utility of this treatment modality for medically refractory supraventricular tachyarrhythmias (SVTs), 10 patients with atrially implanted ...
Sgarbossa E B - - 1992
In spite of a normal pacemaker function, syncope still occurs in some patients with sick sinus syndrome (SSS). Causes often remain unknown. To identify predictors and etiologies of this bothersome symptom, we studied 507 patients who received atrial, ventricular, and dual-chamber pacemakers for SSS. During a mean follow-up of 62 ...
Resh W - - 1992
Adenosine has a well established negative chronotropic effect on the sinoatrial node. The most widely utilized test of sinus node function remains the sinus node recovery time (SNRT), which generally requires catheterization. We compared the effect of adenosine (150 mcg/kg IV) on the lengthening of sinus cycle length (ADO:SCL) in ...
Grech E D - - 1992
A 45 year old farmer was kicked in the chest by a horse. In the days following the injury episodic breathlessness developed and he was admitted to hospital with right ventricular failure and pulmonary emboli. Echocardiography showed global right ventricular dysfunction but a right ventricular mural thrombus, the likely source ...
Von Doersten P G - - 1992
Ventricular dysphonia is a poorly understood disorder involving ventricular fold participation during phonation. A population of ventricular dysphonia patients was evaluated using phonatory function studies such as laryngovideostroboscopy, advanced acoustic analysis, and electroglottography to identify shared epidemiologic characteristics and to discuss possible neuromuscular mechanisms and causes. Forty patients with ventricular ...
Connelly D T - - 1992
The use of evoked QT-interval and ventricular depolarization gradient as sensors for rate-responsive pacing is described in this article. The QT interval has been used as a biosensor in implantable pacemakers since 1981, and recent refinements have improved the rate response characteristics and simplified the programming of this pacemaker. Recently, ...
Jafri S M - - 1992
Temporary cardiac pacing in the critical care setting can be a lifesaving intervention in a number of clinical situations. A variety of catheter types and pulse generators are available. Insertion techniques include the use of fluoroscopic imaging, intracavitary ECG monitoring, and blind advancement with surface ECG monitoring. This article focuses ...
Lau C P - - 1992
Although a long postventricular atrial refractory period (PVARP) may prevent the occurrence of pacemaker mediated tachycardias and inadvertent tracking of atrial arrhythmias in dual chamber (DDD) pacing, the maximum upper rate will necessarily be compromised. We tested the feasibility of using minute ventilation sensing in a dual chamber rate adaptive ...
Shakespeare C F - - 1992
Pacemaker technology has expanded rapidly in the last thirty years. Each phase of development has been marked by both improvements in clinical benefit and disadvantageous interactions of physiology and technology. Each phase of development has led to smaller, more reliable devices with greater programmability. Advances in generator technology and battery ...
Rekus J F - - 1992
Construction workers who weld, cut or blast structural steel coated with lead-based paint are at significant risk of lead poisoning. Although technology to control these exposures may not have existed when the lead standard was promulgated, it is available today. Employers who do not take steps to protect their employees ...
Negoescu R M - - 1992
The functional anatomy of the sinoatrial node (SAN) in man is first reviewed, together with its possible anatomical substructure. The true group pacemaker (PM) shift under autonomic drive is then related to a continuous competition between the intrinsic auto-firing period hierarchy and the autonomic topological susceptibility hierarchy. Accordingly, the PM ...
Tan U - - 1992
The associations among hand preference, hand skill (peg moving time, PMT) and hand performance (dot filling/20 s) were analyzed in left-handed subjects. In the total sample, the degree of left-hand preference linearly decreased from -100 to zero (Geschwind scores, GSs) as the number of dots placed by the right hand ...
Fredman C S - - 1992
We describe in this report an unusual form of Wenckebach upper rate response produced by a DDD pulse generator with atrial-based lower rate timing. The pacemaker maintained the programmed upper and lower rate intervals at the expense of a prolonged atrial paced-ventricular paced AV interval. This form of upper rate ...
Daniel G B - - 1992
Isolated equine granulocytes (WBC), radiolabeled with 99mTc-hexamethylpropyleneamine oxime (99mTc-HMPAO) or 111In-oxine, were evaluated in vitro for their labeling characteristics, viability, and phagocytic function over a 6-hour postlabeling period. Mean +/- SD labeling efficiency for 111In-oxine-WBC was 62.2 +/- 15.3%, which was significantly (P less than 0.001) higher than that for ...
Berns E - - 1992
This report describes a case in which an implanted pacemaker programmed to perform noninvasive electrophysiology testing resulted in an unusual form of pacemaker mediated tachycardia. The method of chest wall stimulation was used by programming a unipolar, triggered pacing mode with a short refractory period. In the AAT mode, far-field ...
Mohan J C - - 1992
Conflicting data have been reported regarding adjustment of atrioventricular (AV) interval to maximise hemodynamic performance of dual chamber pacemakers. Eleven consecutive patients with complete heart block and dual chamber pacemakers were paced at three AV intervals (150, 200, 250 msec) and free running rates (60-93 bpm, mean 73 +/- 12 ...
Spittell P C PC Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, Rochester, MN - - 1992
We reviewed the incidence, clinical features, current diagnostic evaluations, and treatments of venous complications that can occur after implantation of a transvenous pacemaker. Of the approximately 80 published articles on the potential venous complications after implantation of a permanent transvenous pacemaker, we selected 63 that addressed the clinical features, diagnosis, ...
Esperer H D - - 1992
Seventeen patients, in whom an epicardial (n = 7) or a transvenous DDDM pacemaker system had been implanted between June 1988 and October 1990, were followed up for pacemaker and lead related complications, pacemaker longevity, and electrophysiological lead parameters. The mean follow-up interval was 18 +/- 12 months, maximum 34 ...
Goater C P - - 1992
Density-dependence in worm establishment, numbers, biomass and larval production were examined in primary infections of 0, 10, 40, 80 and 160 larvae of the lung nematode, Rhabdias bufonis in the common toad, Bufo bufo. The infection procedure established 4 non-overlapping levels of infection which persisted until 6 weeks post-infection (p.i.), ...
Tworek D A - - 1992
The possible interference of drugs with the function of implanted electrical cardiac devices in two patients is described, and the literature on the interaction between these drugs and devices is reviewed. A 59-year-old woman had a permanent pacemaker implanted after diagnosis of tachycardia-bradycardia syndrome, and her drug regimen of digoxin, ...
Greenhut S E - - 1992
Analysis of the paced electrocardiogram (ECG) is important to the follow-up evaluation of patients with implanted pacemakers. Because of the complexity and variability of pacemaker algorithms, diagnosis of paced ECGs is often considerably more difficult than the interpretation of usual ECGs. Automated interpretation of the paced ECG can provide great ...
Lau C P - - 1992
The role of implantable sensors to control pacemaker mediated tachycardias was investigated in 16 patients with two different dual chamber rate adaptive (DDDR) pacemakers, which sensed eiter minute ventilation (DDDR-Meta, nine patients) or body acceleration (Relay, seven patients). Successive atrial sensed events beyond a programmable rate occurring in the absence ...
Sevaptsidis E - - 1992
An analog mapping system using a true bipolar left ventricular balloon electrode array is described, which enables simultaneous unipolar and bipolar recordings. It is an adaptation of a previous clinical analog mapping system used in the investigation of ventricular arrhythmias. The bipolar balloon array consists of 112 electrode pairs, each ...
Vanerio G - - 1991
The new DDDR pacemaker META DDDR utilizes a minute ventilation sensor based on transthoracic impedance measurements. The sensor determines the metabolic indicated interval, the atrioventricular (AV) delay and the postventricular atrial refractory period (PVARP). The baseline PVARP must be carefully selected to define nonphysiological tachycardias. If a P wave falls ...
Shiratsuchi Y - - 1991
Masticatory function was examined in 17 patients with mandibular prognathism before and after bilateral sagittal splitting osteotomy of the mandibular rami. Masticatory efficiency was measured by means of a spectrophotometer, using adenosine triphosphate (ATP) granules, the biting force and occlusal contact area. Masticatory functions showed a tendency to gradual improvement ...
Foutch P G - - 1991
We prospectively screened 129 asymptomatic subjects (mean age 64 yr) with flexible sigmoidoscopy. Colonoscopy was performed at a later date, regardless of the sigmoidoscopic result. Our intent was 1) to establish the prevalence of proximal neoplasms in patients with and without hyperplastic polyps within reach of the 60-cm sigmoidoscope and ...
Kataoka H - - 1991
I report a case of end-stage dilated cardiomyopathy with first-degree atrioventricular (AV) block, which had been resistant to intensive medical therapy and was eventually treated by DDD pacemaker. The optimal AV interval setting was decided using invasive right-heart catheterization and Doppler echocardiography. At a pacing rate of 92/minute, an AV ...
Von Knorre G H - - 1991
Pacemaker circus movement tachycardia (PCMT) during DDD pacing is usually sustained by retrograde natural and antegrade electronic atrioventricular (AV) conduction. As PCMT is often initiated by a ventricular premature beat (VPB) one method of its prevention is the programming of an atrial stimulus synchronously following a ventricular extrasystole. A patient ...
Schneider H T - - 1991
To compare the fragmentation efficiency of three different shockwave systems, 63 human gallstone triplets were disintegrated in vitro using an electrohydraulic (MPL 9000, Dornier), an electromagnetic (Lithostar Plus, Siemens) and a piezoelectric (Piezolith 2300, R. Wolf) lithotripter. Since each stone triplet was obtained from the same gallbladder, the concrements of ...
Agner T - - 1991
Basic physiological characteristics were examined in the uninvolved skin of 39 patients with hand eczema and in 39 healthy controls. Susceptibility to sodium lauryl sulphate (SLS)-induced irritant dermatitis was evaluated by the application of a single 24-h SLS patch test to the upper arm. Transepidermal water loss (TEWL) was measured ...
Czihak G - - 1991
Procaine-treated eggs can be penetrated by more than one spermatozoon. Supernumerary male pronuclei can fuse with the female one giving raise to multipolar spindles or remain isolated within the egg's cytoplasm forming their own spindle. In all types of multiple mitotic figures (asters and spindles) the distribution of asters is ...
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