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1.
Atrial Septal Versus Atrial Appendage Pacing:   总被引:5,自引:0,他引:5  
HERMIDA, J.-S., et al. : Atrial Septal Versus Atrial Appendage Pacing: Feasibility and Effects on Atrial Conduction, Interatrial Synchronization, and Atrioventricular Sequence. Atrial septal (Se-P) and atrial appendage pacing (Ap-P) were compared in a randomized, controlled study to assess the feasibility, the reliability, and the effects of Se-P on atrial conduction, interatrial synchronization, and the AV sequence. The main baseline characteristics of the patients were comparable in both groups. There was no difference in feasibility or reliability between the two techniques. Compared to Ap-P   (n = 28)   , Se-P   (n = 28)   decreased the P wave duration, left atrial electromechanical delay (LAEMD), and interatrial interval (−1.6% vs   +28%, P < 0.001; −3%   vs   + 30%, P < 0.001; −130%   vs   + 78%, P < 0.001   ); it induced a smaller increase of the right AEMD, a slight reversal of the timing of the atrial systoles and a shortening of the PR interval (−13% vs   + 25%, P < 0.001   ) and of the interval separating atrial systoles from ventricular activation. Finally, the shortening of the PR interval was smaller during high Se-P versus low Se-P. Se-P avoids the undesirable prolongation of the atrial, interatrial, and AV conductions observed during Ap-P. In addition, Se-P creates a slight reversal of the timing of the atrial systoles and induces a shortening of PR interval, the extent of which could depend on the height of the pacing site on the septum. (PACE 2003; 26[Pt. I]:26–35)  相似文献   
2.
Workplace design and upkeep, or human factors, are frequently advanced for explaining so-called Occupational Slip, Trip and Fall Accidents (OSTFAs). Despite scientific progress, these accidents, and more broadly Occupational Accidents with Movement Disturbance (OAMDs), are also commonly considered to be “simple”. This paper aims to stimulate changes in such perceptions by focusing on organisational factors that often combine with other accident factors to cause movement disturbance and injury in work situations. These factors frequently lead to arbitration between production and safety, which involves implementation of controls by workers. These controls can lead to greater worker exposure to OAMD risk. We propose a model that focuses on such controls to account specifically for the need to confront production and safety logics within a company and to enhance the potential for appropriate prevention action. These are then integrated into the set of controls highlighted by work organisation model developed by the NIOSH.  相似文献   
3.
Cardiac resynchronization therapy (CRT) is an emerging therapy that improves symptoms and exercise tolerance in patients with advanced heart failure, left ventricular systolic dysfunction, and intraventricular conduction delay. By correcting the AV, interventricular, and intraventricular dyssynchrony induced by conduction disorders, controlled studies have shown that CRT improved functional status, decreased heart failure hospitalization rate, and might have a positive effect on left ventricular remodeling. Recent and preliminary data from the COMPANION trial suggest that CRT alone or in association with defibrillator capacity significantly reduced total mortality and hospitalization and that total mortality was significantly reduced only in the CRT plus implantable cardioverter defibrillator (ICD) group. Many questions remain unanswered, particularly the selection of responder patients. (J Cardiovasc Electrophysiol, Vol. 14, pp. S27-S29, September 2003, Suppl.)  相似文献   
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Aim The aim of this study was to assess the independent role of cerebral lesions on ultrasound scan, and several other neonatal and obstetric factors, as potential predictors of cerebral palsy (CP) in a large population‐based cohort of very preterm infants. Method As part of EPIPAGE, a population‐based prospective cohort study, perinatal data and outcome at 5 years of age were recorded for 1812 infants born before 33 weeks of gestation in nine regions of France in 1997. Results The study group comprised 942 males (52%) and 870 females with a mean gestational age of 30 weeks (SD 2wks; range 24–32wks) and a mean birthweight of 1367g (SD 393g; range 450–2645g). CP was diagnosed at 5 years of age in 159 infants (prevalence 9%; 95% confidence interval [CI] 7–10%), 97 males and 62 females, with a mean gestational age of 29 weeks (SD 2wks; range 24–32wks) and a mean birthweight of 1305g (SD 386g; range 500–2480g). Among this group, 67% walked without aid, 14% walked with aid, and 19% were unable to walk. Spastic, ataxic, and dyskinetic CP accounted for 89%, 7%, and 4% of cases respectively. The prevalence of CP was 61% among infants with cystic periventricular leukomalacia, 50% in infants with intraparenchymal haemorrhage, 8% in infants with grade I intraventricular haemorrhage, and 4% in infants without a detectable cerebral lesion. After controlling for cerebral lesions and obstetric and neonatal factors, only male sex (odds ratio [OR] 1.52; 95% CI 1.03–2.25) and preterm premature rupture of membranes or preterm labour (OR 1.72; 95% CI 0.95–3.14) were predictors of the development of CP in very preterm infants. Interpretation Cerebral lesions were the most important predictor of CP in very preterm infants. In addition, infant sex and preterm premature rupture of membranes or preterm labour were also independent predictors of CP.  相似文献   
7.
Stenting of coronary arteries is currently used in clinical practice. The aim of this prospective registry was to assess the feasibility and the safety of stent implantation without balloon predilatation in noncomplex and noncalcifed lesions. One hundred six stents were implanted in 85 patients who underwent percutaneous coronary angioplasty (PTCA) of native vessels (n = 95) or bypass grafts (n = 11). The lesions were type A (21%) or B1 (79%). The stent was a tubular or a coil stent in 71 ± and 29% of the cases, respectively. The angiographic success rate was 94%. The maximal pressure was 12.1 ± 2.1 atm. In only 7 cases, it was not possible to cross the stenosis with the stent, necessitating retrieval of it and predilation with a balloon before stent implantation. Three dissections after stent implantation were treated by a second stent implantation. The primary success rate was 98% (no acute closure or myocardial infarction). A clinical follow-up was obtained in 98% of patients with a mean delay of 6 ± 0.5 months. Eighty-one percent of patients were asymptomatic. The target lesion revascularization rate was 9.4%. Four patients underwent a new PTCA and four patients a coronary artery bypass graft surgery. This technique of stent implantation appears to be safe with good immediate and midterm results. A prospective randomized trial comparing this technique to the standard technique of stent delivery in noncomplex lesions is currently ongoing with an intravascular ultrasound substudy.  相似文献   
8.
The first series of transradial coronary angiograms was carried out by Lucien Campeau and published in 1989. The devices available at that time made the technique difficult to perform. Four years later, when stenting started being widely used with a significant rate of local complications induced by Coumadin treatment, F. Kiemeneij proposed the radial approach as a good alternative to the femoral approach to reduce the rate of local complications. Since then, the use of the radial approach has been increasing, though it remains limited. The first reason for this lies in the significant learning period that is all the longer as a low percentage of patients are treated via this approach. This is why we think it is preferable to perform at least 25% of all procedures, and especially coronary angiograms, through this approach before setting up a radial program. Patients with contraindications to the femoral approach (anticoagulation or GP IIb/IIIa inhibitors, obesity, aneurysm of the abdominal aorta, or vessel disease of the lower limbs, etc.) should be selected. The second reason is the small diameter of the radial artery that can generate a number of problems when large diameter guiding catheters are used (7Fr or 8Fr). However, the reduction in guiding‐catheter size, and the increasing use of 6Fr catheters should solve this problem. In our center, the femoral approach is usually selected when 7Fr or 8Fr catheters are used. It is to be noted that the radial approach is now widely used in some interventional cardiology centers where the learning period has been completed. With operator experience, puncture failure is extremely rare and the technical failure rate is around 1%, mainly due to the anatomic variations of the radial artery (antebrachial and humeral loops). Apart from the difficulties associated with the learning curve, the radial approach has few limitations. The procedure and x‐ray exposure times are slightly longer for coronary angiography but not for angioplasty. The risk of radial occlusion ranges from 2% to 5%, however, radial occlusion is asymptomatic in patients with a normal Allen's test. Conversely, the radial approach has many advantages. Patient comfort is significantly improved due to the ease of radial compression, ambulation is almost immediate, and the rate of local complications is almost nil. Same day discharge following coronary angiography and angioplasty can be considered. Finally, with the increasing use of GP IIb/IIIa inhibitors, sometimes in combination with thrombolysis in the treatment of myocardial infarction, the radial approach could become the preferred approach in this setting.  相似文献   
9.
Six patients (5 men, 1 woman) with a history ranging from 3–16 years of resistant vagal atrial arrhythmias were treated by atrial pacing at a rate of 90Jmin. These patients have been followed up for an average of 5.5 years (range 2–11 years) with favorable resutls. The arrhythmias were charactemed by daily or weekly attacks of rypical alrial flutter and atrial fibrillalion occurring mainly or exclusively at night, at rest, or in the digestive periods in otherwise normal hearts of middle-aged palients (first attack between 25 and 54, mean 40). The arrhythmias werc resistant to quinidinc, and were usually aggravated by digitalis, beta-blockers and verapamil. Amiodaroneisusually the only effective drug in this syndrome, but was not used before pacing in the 2 first cases, and was in effective in the other 4 cases. Electrophysiologic studies confirmed the absence of sick sinus syndrome, and the close relationship betwecn a relative bradycardia and the onset of the arrhythmia. Atrial pacing alone totally controiled the arrhythmia in 1 palient; amiodarone was used in conjunction with pacing in 3 palients. In 1 patient the improvement was clear but incomplete, and in 1 patient permanent alrial fibrillation occurred shortly afler pacemaker implantalion.  相似文献   
10.
Cardiac tamponade complicating catheter ablation of atrial fibrillation (AF) occurs in approximately 1% of pulmonary vein isolation (PVI), and up to 6% of linear ablation procedures. We reviewed 348 consecutive AF ablation (including repeat) procedures over 1 year, which all included PVI, with additional linear lesions at the mitral isthmus in 73%, and cavotricuspid isthmus (CTI) in 76%. An irrigated-tip ablation catheter was used, with power limited to 25–35 W for PVI and 45–60 W for linear lesions. Tamponade occurred in seven men and three women (2.9% of the population) during the creation of linear ablation lesions. Mechanical perforations occurred in two patients, and "popping" during radiofrequency (RF) energy delivery at the mitral isthmus in six, and at the CTI in two patients. Peak RF power was significantly higher in patients with than without tamponade (53 ± 4 W vs 48 ± 7 W; P = 0.02), and was greater than 48 W in all cases of "popping." In the following year, RF power for linear ablation was limited to ≤42 W. Among 398 procedures, tamponade occurred in four patients (1.0%; P = 0.047 vs first year), three from "popping" and one from mechanical trauma. Procedural success rate remained the same despite reduction of power. Risk of tamponade was highest during linear ablation, mainly associated with high energy delivery and "popping." Reducing the energy limited, though did not eliminate this complication.  相似文献   
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