Search Results
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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 ...
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, ...
Sgarbossa E B EB Dept. of Cardiology, Cleveland Clinic Foundation, OH - - 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 ...
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 G Department of Cardiology, Cleveland Clinic Foundation, Ohio - - 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 ...
Peeters A J - - 1991
In recent studies from Sweden an increased prevalence of HLA-B27 associated diseases and of HLA-B27 was found in an unselected group of men with permanently implanted pacemakers and with a heart block. Furthermore, a significantly increased prevalence of HLA-B27 was found in men with a pacemaker who had no clinical ...
Van Erckelens F - - 1991
The case of a woman with an asymptomatic transvenous left ventricular endocardial pacemaker lead is presented. The chest X ray and the electrocardiogram suggested pacemaker catheter malposition. By two-dimensional echocardiography, the pacemaker lead was shown to cross from the left atrium through the mitral valve and implant in the left ...
van Gelder L M - - 1991
Holter recording of a patient with an implanted dual chamber rate responsive pacemaker revealed an electrocardiogram, where ventricular depolarization seemed to be initiated by the atrial stimulus. In a second patient with a VVI pacemaker, Holter recording showed delay of the pacemaker impulse that was registered after the onset of ...
Silka M J - - 1991
A young patient, who experienced a cerebral embolic event 30 days after transvenous pacemaker lead placement, is reported. This patient had previously been paced with an epicardial lead without evidence of right to left intracardiac shunt. However, hemodynamic evaluation post-embolism demonstrated a marked temporal disparity of the pulmonary and systemic ...
Myers M R - - 1991
Within a few months of implantation, permanent pacemaker leads become ensheathed in fibrocollagenous tissue. This tissue may anchor the lead so that it is difficult, dangerous, or impossible to remove it. Leads with bulbous or finned tips are particularly resistant to extraction. The risks of applying traction to an entrapped ...
Walsh E G - - 1991
The resonant frequency of the wrist has been measured in sixteen hypermobile and nine normal women at ten levels of peak torque. At the lowest level the results were identical but at the others the hypermobile values were lower. Damping and thixotropy appeared to be normal. In another group the ...
Korzets A - - 1991
Two cases of subclavian vein stenosis secondary to permanent cardiac pacemakers are presented. Both stenoses were asymptomatic until arteriovenous fistulae/grafts were constructed in order to initiate haemodialysis. One patient experienced severe oedema of the arm which necessitated surgical closure of the graft. A literature review into major venous stenosis and ...
Benrey J - - 1991
During their 33-year history of clinical use, cardiac pacemakers have evolved from devices primarily intended to save lives into complex systems designed to improve the cardiac patient's overall quality of life. To help physicians cope with this rapidly changing field, this review outlines current indications for pacemaker therapy and examines ...
Della Bella P - - 1990
Holter monitoring in a 75-year-old man with a VVI pacemaker with rate hysteresis and concomitant quinidine treatment documented the occurrence of several episodes of non-sustained polymorphous ventricular tachycardia, triggered by each first paced beat following the longer escape interval. These arrhythmias disappeared when quinidine was withdrawn or when the pacemaker ...
Kirby R L - - 1990
Coupling between cardiac and locomotor rhythms has been identified while people walk, run, hop and cycle at cadences natural to them. To test the hypothesis that cardiac-locomotor coupling occurs during finger tapping, we studied 20 normal subjects tapping a telegraph key at a comfortable rate for 10 min. 15 subjects ...
Vanerio G - - 1990
STUDY OBJECTIVE: Determine the effect of percutaneous catheter ablation (CA) on permanent pacemakers. MEASUREMENTS AND RESULTS: Twenty-three patients who underwent CA at The Cleveland Clinic Foundation from September 1983 to January 1990, and had a previously implanted pacemaker were studied. Electrocardiographic data during the CA procedure and clinic data including ...
Cosentino S - - 1990
The occurrence of pollens and molds in the atmosphere of Cagliari, Italy over a 3-year period (1986-88) is reported. Pollen grains are present in the air from February to July, with a maximum in May. Urticaceae and Cupressaceae were the major contributors to the total pollen airspora, followed by Graminaceae, ...
Grier D - - 1990
The chest radiographs of 600 consecutive patients undergoing insertion of a permanent cardiac pacemaker were reviewed to determine the incidence and nature of abnormalities present. Abnormalities were detected on the chest radiographs of 131 patients (21.8%). Unsatisfactory electrode tip position and other features related to the electrode wire were commonest ...
DeHaan K C - - 1990
Forty-three pregnant Dorset and Dorset crossbred ewes were assigned randomly to a control group or implanted with either 300 mg trenbolone acetate (Low TBA) or 1,200 mg trenbolone acetate (High TBA) between d 40 and 60 of gestation. Adjusted weaning weights for ewe lambs were 23.3% less (P less than ...
Durand L G - - 1990
A surgical protocol was designed to implant in dogs a programmable atrioventricular pacemaker and to destroy the bundle of His with one to four 0.1 ml formaldehyde injections. The heart rate and P-R interval were paced at 100 beats min-1 and 75 ms, respectively. Cardiac inotropy was then varied in ...
Kertes P J - - 1990
In Australia, most patients requiring permanent cardiac pacing have either high grade atrioventricular block or sick sinus syndrome. Many receive simple ventricular demand pacemakers, but more 'physiological' systems are now available that allow changes in pacing rate depending on metabolic needs. The indications for pacemakers and the types available are ...
Marshall I - - 1990
Some patients undergoing cardiothoracic surgery require cardiac pacing. Surgical diathermy interferes with the operation of external pacemakers, and can cause a loss of cardiac output. The addition of a simple two-stage LC filter to the front end of the pacemaker enables cardiac output to be maintained during the use of ...
Sturgis L M - - 1990
4 physiological measures--electromyogram, respiration rate, heart rate, and skin conductance--were recorded for 11 high and 11 low hypnotizable Ss. It was hypothesized (a) that physiological responsiveness during hypnosis would vary depending on the nature of the task instructions, and (b) that high hypnotizable Ss would show more physiological responsiveness than ...
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