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71.
72.
Persistent Electrical Isolation of Pulmonary Veins . Introduction: Aim of this study was to compare efficacy and safety of the new ThermoCool Surround Flow® catheter (SFc) versus the ThermoCool® (TCc) in achieving persistent circumferential electrical isolation of the pulmonary veins (PVs) in patients with paroxysmal atrial fibrillation (AF). Methods and Results: This multicenter, randomized, controlled study enrolled patients suffering from paroxysmal AF. Randomization was run in a one‐to‐one fashion between radiofrequency ablation by TCc or SFc. Aim of PVs ablation was documentation of electrical isolation with exit/entrance block recorded on a circular catheter. Among the 106 enrolled patients, 52 (49.0%) were randomized to TCc and 54 (51.0%) to SFc. Total volume of infused saline solution during the procedure was lower in the SFc than in TCc group (752.7 ± 268.6 mL vs 1,165.9 ± 436.2 mL, P < 0.0001). Number of identified and isolated PVs was similar in the 2 groups. Number of PVs remaining isolated 30 minutes after ablation was higher in the SFc than in TCc group (95.2% vs 90.5%, P < 0.03), mainly driven by acute ablation result in the left PVs (96.1% vs 89.7%, P < 0.04). Complications were seldom and observed only in the TCc group (0% vs 3.84%, P < 0.03). At 6‐month follow‐up SFc patients reported a trend toward less AF recurrences compared to those in the TCc group (22.9% vs 27.0%, P = 0.69). Conclusion: PV isolation by SFc lowered the rate of left PV early reconnections and reduced the volume of infused saline solution while maintaining the safety profile of AF ablation. (J Cardiovasc Electrophysiol, Vol. 24, pp. 269‐273, March 2013)  相似文献   
73.
Purpose: In patients on oral anticoagulation (OAC) undergoing coronary stenting (PCI-S), procedural management and in-hospital outcome have never been specifically and prospectively investigated. Also, the contribution of early bleeding to the relevant hemorrhagic rate reported at follow-up with triple therapy of OAC, aspirin, and clopidogrel is largely unknown.
Methods: Consecutive patients with indication for OAC undergoing PCI-S at 5 centers were enrolled and prospectively evaluated.
Results: Out of 3410 patients undergoing PCI-S in the study period, indication for OAC was present in 4.8%. Femoral approach and bare metal stents were the most frequently used. During PCI-S, OAC was continued in about 30% of patients, whereas in about 20% heparin bridging was carried out. Glycoprotein IIb/IIIa inhibitors were rarely used (11%), whereas a standard bolus of unfractionated heparin was given in 93% of cases. Major adverse cardiovascular events (MACE) occurred in 4.8% of patients and major bleeding in 4.3%. No predictors of MACE or bleeding were identified, although the femoral approach was of borderline significance for major bleeding (OR 4.6, 95% CI 1.0–20.8; P = 0.05). A history of previous hemorrhage (OR 5.3, 95% CI 1.6–18.1; P = 0.007) predicted Carbofilm™-coated stent implantation.
Conclusions: A limited, albeit clinically relevant, proportion of patients undergoing PCI-S has indication for OAC. Procedural management appears not substantially different from that of common patients. In-hospital major bleeding is relevant and should be taken into account when evaluating the overall hemorrhagic rate at a medium- to long-term follow-up.  相似文献   
74.
24-Hour Heart Rate Variability in Patients with Vasovagal Syncope   总被引:3,自引:0,他引:3  
Since alterations in the autonomic nervous system are thought to play a major role in the pathogenesis of vasovagal syncope, we characterized the chronic autonomic profile of 44 patients with syncope and 20 healthy subjects by means of heart rate variability using 24-hour Holter recordings (time- and frequency-domain indexes), and evaluated whether the different types of responses to tilting (vasodepressive versus cardioinhibitory) could be associated with different cardiac autonomic patterns. Twenty-three patients exhibited a positive response to tilting, which was vasodepressive in 11 patients and cardioinhibitory in 12 patients. All vasodepressive patients had a standard deviation of the averages of NN (SDANN) intervals in all 5-minute segments lower than 100 ms. Patients with vasodepressive syncope also had significantly lower values of RMSSD (the 24-hour square root of the mean of the sum of the squares of differences between adjacent normal RR intervals) than those with cardioinhibitory response, and lacked the day-night rhythm of the low frequency/high frequency ratio. However, only SDANN values correctly identified patients with vasodepressive response to tilting. We conclude that (1) the population of patients with vasovagal syncope is heterogeneous, (2) patients with vasodepressive syncope have a peculiar chronic autonomic profile as assessed by 24-hour heart rate variability analysis, and (3) the evaluation of the autonomic profile in 24-hour Holter recordings could be of value in the diagnosis of patients with syncope.  相似文献   
75.
Background: Atrial fibrillation (AF) is a major cause of morbidity and mortality, especially in patients with congestive heart failure.
Objectives: The purposes of this international, prospective multicenter study were to evaluate the efficacy of atrial shock therapy in patients with a cardiac resynchronization therapy defibrillator (CRT-D) and to evaluate the safety of the new CRT-D. The effectiveness of a new wireless telemetry system was also evaluated.
Methods: A total of 282 patients, without permanent AF, who had indications for a CRT-D were included. Atrial shock therapy was tested on both spontaneous and induced AF episodes. The effectiveness of the Medtronic wireless telemetry system (Conexus; Medtronic Inc., Minneapolis, MN, USA) was also tested. Secondary endpoints included the heart failure Clinical Composite Response, system performance evaluation, and adverse event summary.
Results: Atrial shock therapy was successful in 168 of 171 episodes (98.2%). Of these, 138 episodes were induced and 33 were spontaneous. Successful cardioversion occurred in 137 of the 138 induced-AF episodes (86.1% with 12 joule (J), 13.1% with 24 J, and 0.7% with 35 J). During the first 3 months of implant, there were 43 system-related complications in 37 subjects out of 278 subjects. There were 1,999 Conexus telemetry uses recorded during this study. This includes 282 uses during the implant procedure. There were no cases of complete loss of telemetry or any adverse events reported using this system.
Conclusion: We achieved an atrial shock efficacy of 98.2% in patients who met standard CRT-D indications. The wireless telemetry performed well with no reported unanticipated adverse device effects.  相似文献   
76.
The level of procedural skills improves in normal individuals when the acquisition is followed by a period of sleep rather than wake. If sleep plays an important role in the consolidation process the advantage it provides should be reduced or delayed when its organization is altered, as in patients with chronic sleep disorders. To test this prediction in patients with narcolepsy–cataplexy (NC), who usually have a more fragmented organization of sleep than normals, we compared the initial, intermediate and delayed level of consolidation of visual skills . Twenty-two drug-naive NC patients and 22 individually-matched controls underwent training at a texture discrimination task (TDT) and were re-tested on the next morning (after a night spent in laboratory with polysomnography) and after another six nights (spent at home). TDT performance was worse in patients than controls at training and at both retrieval sessions and the time course of consolidation was different in NC patients (who improved mainly from next-day to 7th-day retrieval session) compared with controls. Moreover, the less-improving patients at next-day retrieval had a wider disorganization of sleep, probably because of an episode of rapid eye movement (REM) sleep at sleep onset REM, on post-training night more frequently than more-improving patients. These findings suggest that the time course of the consolidation process of procedural skills may be widely influenced by the characteristics of sleep organization (varying night-by-night much more in NC patients than controls) during post-training night.  相似文献   
77.
Background: We used a cardiac resynchronization therapy defibrillator device with an algorithm for automatic verification of left ventricular (LV) stimulation to understand LV threshold variability, such as to provide hints to program the algorithm features. We also evaluated the algorithm performance over long term, and tested a stimulation setting to achieve 99% effective stimulation while maximizing device longevity. Methods: The LV output was programmed as threshold + 0.5 V; the upper limit of LV output adjustment was 6 V at programmed pulse width. The algorithm is insensitive to the strength of the pacing pulse, thus pulse width was conveniently programmed to minimize the use of voltage multipliers in all the patients. Follow‐ups occurred at 1 month, then every 3 months, for clinical assessment and manual threshold verification. The efficacy of this programming at long term was also evaluated by Holter validation of LV stimulation. Results: Twenty patients were followed for 14 ± 5 months (6–21). LV threshold showed no changes in 97% of consecutive days, whereas a 0.5‐V and 1‐V increase occurred, respectively, in 2.3% and 0.6%. Maximum variability of LV threshold was ≤0.5 V during 90% of the follow‐up period. Our programming of LV output provided 99–100% effective stimulation in 18 of 20 patients, and 90% efficacy in two patients because of missed threshold measurements. A 25% increase of device longevity can be expected by this programming. Conclusions: LV threshold variability is truly modest. Daily update of LV threshold should be improved to ensure 100% LV stimulation by a threshold + 0.5 V safety margin. Device longevity is maximized when LV stimulation occurs below battery voltage.  相似文献   
78.
Summary. The time to peak velocity was measured at the level of the ascending aorta and pulmonary artery by Doppler echocardiography in 38 small-for-gestational age (SGA) fetuses before and during maternal hyperoxygenation. The values were compared to a reference range derived from the study of 142 appropriate-for-gestational age (AGA) fetuses. In the SGA fetuses the time to peak velocity at the level of pulmonary artery was significantly lower and at the level of the aorta significantly higher than in AGA fetuses. During maternal hyperoxygenation the aortic time to peak velocity decreased towards normal range but there was no significant change at the level of the pulmonary artery. These results may indicate variations of aortic and pulmonary pressures in SGA fetuses that can be partially modified by maternal hyperoxygenation and which may be associated with changes in the peripheral resistance of the cerebral circulation.  相似文献   
79.
ABSTRACT: Carcinoembryonic antigen (CEA) levels were serially determined in 125 patients with breast cancer in order to study the diagnostic and prognostic use of serum CEA levels before and/or after surgery and during treatment with hormonal and chemotherapy. Serum CEA levels were elevated in 15.5% of nonmetastatic patients. Carcinoembryonic antigen increased according to stage (TNM classification); and a direct relationship between positive CEA levels and subsequent recurrence was found. After a three-year postoperative interval a 50% survival rate was exhibited in CEA-positive patients vs an 88% survival rate in those patients found to be CEA negative. There is a definite correlation between the trend of serial CEA values and the response to therapy and the development of metastases despite the fact that metastases occurred in CEA-negative patients. Therefore CEA assay is a useful and simple adjuvant test of monitoring metastatic and nonmetastatic breast cancer.  相似文献   
80.
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