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Darbar D Warman EN Hammill SC Friedman PA;Worldwide Jewel AF Investigators 《Pacing and clinical electrophysiology : PACE》2005,28(10):1047-1051
BACKGROUND: Because the natural history of atrial tachyarrhythmia (AT) is not known in patients with implantable cardioverter-defibrillators (ICDs) but without device-based atrial therapies, we aimed to describe the characteristics and recurrence of AT in such patients. METHODS: In this multicenter trial, 269 patients with standard indications for ICD placement and 2 episodes of AT in the preceding year received a dual-chamber ICD capable of logging AT. Patients were randomly assigned to 3-month periods of atrial therapies "on" or "off." This analysis considered only the 118 patients with atrial therapies programmed off at ICD placement. RESULTS: Fifty-eight patients (49%) had at least 1 AT episode longer than 1 minute, and 21 (18%) had at least 1 prolonged episode (>24 hours). The median episode frequency for each patient (episodes per month) was 1.8 episodes longer than 1 minute, 0.8 longer than 1 hour, and 0 longer than 24 hours. The median AT burden was 12.2 hours per month. CONCLUSIONS: Patients with standard ICD indications and history of AT have infrequent episodes, frequent short episodes, or prolonged episodes of AT-atrial fibrillation. However, the clinical characteristics examined did not distinguish among the groups. Improved diagnostic tools may help identify patients at risk for development of AT, thereby allowing specific therapies to be targeted to each group of patients. 相似文献
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Kinnison ML; White RI Jr; Auster M; Hewes R; Mitchell SE; Shuman L; Gallacher D 《Radiology》1985,154(2):349-351
As an alternative to performing interventional radiology on inpatients under the care of internists and surgeons, the authors have established a cardiovascular radiology admitting service for well-screened, elective patients. The patients are admitted under the care of a cardiovascular radiology fellow and a staff physician. From April 1982 to December 1983, 133 patients were admitted to the service. Patients are cared for in a surgical ward or in an intermediate unit, as determined by the clinical situation. Advantages of this approach include a broader patient referral base, improved rapport with clinical colleagues and patients, improved follow-up data, and rapid evaluation and treatment, resulting in short hospital stays. The major disadvantages involve the commitment of time and staff necessary to provide quality care. The concept of the interventional radiologist in the role of admitting physician has important implications in terms of negotiations for additional financial compensation, commensurate with the skill and time required for performing these procedures and caring for the patient. 相似文献
76.
Brendan Humphries Geoff Warman Jason Purton Tim L. A. Doyle Eric Dugan 《Journal of Sports Science and Medicine》2004,3(1):16-22
At present there appears to be a need for research conducted on the effects of vibration on the contractile ability of skeletal muscle tissue. The aim of this study was to address this issue by examining the effects of a superimposed muscle/tendon vibration at 50.42±1.16 Hz (acceleration 13.24 ± 0.18ms-2: displacement ≈5mm) on muscular activation and maximal isometric contraction. Sixteen participants with a mean age, body mass, and height of 22 ± 4.4 years, 73.2 ± 11.7 kg and 173.1 ± 9.7 cms, respectively, were recruited for this study. Electromyography and accelerometry from the rectus femoris, and maximal isometric force data characteristics were collected from the dominant limb under conditions of vibration, and no-vibration. A superimposed 50 Hz vibration was used during the contraction phase for the maximal isometric leg extension for the condition of vibration. A one-way ANOVA revealed no significant (p > 0.05) differences between the vibration and no-vibration conditions for peak normalized EMGRMS (84.74% Vs 88.1%) values. An ANOVA revealed significant (p > 0.05) differences between the peak fundamental frequencies of the FFT between the conditions vibration (27.1 ± 12.2 Hz) and no-vibration (9.8 ± 3.5 Hz). Peak isometric force, peak rate of force development, rate of force development at times 0.05, 0.01, 0.1, 0.5 seconds, and rate of force development at 50, 75, and 90% of peak force were not significantly different. The results of this study suggest that the application of vibration stimulation at 50 Hz during the contraction does not contribute to muscle activation, or enhance force production for maximal isometric contractions.
Key Points
- The application of a vibratory stimulation to the human body increases the normal acceleration resulting in an increase in force and a change in performance
- This study was to address this issue by examining the effects of a direct superimposed muscle/tendon vibration at 50 Hz on isometric strength characteristics
- No improvement or change in isometric force or rate of force development
- No changes to peak normalized EMGRMS values
77.
78.
Neilson DE Feiler HS Wilhelmsen KC Lynn A Eiben RM Kerr DS Warman ML 《Annals of neurology》2004,55(2):291-294
In autosomal dominant acute necrotizing encephalopathy (ADANE), apparently healthy children develop necrotizing lesions in their thalami and brainstems in the course of febrile illnesses. We used DNA from affected subjects and obligate carriers to map ADANE to a 6.5Mb region on chromosome 2. Sequencing of four candidate genes in the interval (BCL2L11, ST6GalII, CHT1, and FLJ20019), involved in apoptosis, viral recognition, choline transport, and electron transport, showed no disease causing mutations. 相似文献
79.
Cognitive-behavioral therapy (CBT) has a proven role as an adjunct to antipsychotic medication and remediative approaches such as social skills training in the management of residual symptoms of chronic schizophrenia. Positive symptoms, depression, and overall symptoms appear to be viable treatment targets for CBT with a less pronounced effect on negative symptoms. The effect size at end of therapy is strong, with durability at short-term follow up. CBT can be used safely in patients with schizophrenia, and caregivers can help with homework exercises. There is also evidence that psychiatric nurses in the community can use CBT effectively with this patient group under supervision. CBT can be combined with family therapy and assertive community treatment programs targeted to reduce relapse. CBT improves the coping of patients with schizophrenia through improved adherence and symptom management. CBT techniques include development of trust, normalizing, coping strategy enhancement, reality testing, and work with dysfunctional affective and behavioral reactions to psychotic symptoms. An enhanced response to CBT would be expected when given with low dose cognitively enhancing atypical antipsychotic medication. 相似文献
80.
Atrial pacing lead location alters the effects of atrioventricular delay on atrial and ventricular hemodynamics 总被引:1,自引:0,他引:1
Hettrick DA Euler DE Pagel PS Musley SK Warman EN Ziegler PD Mehra R 《Pacing and clinical electrophysiology : PACE》2002,25(6):888-896
The combined role of atrial pacing lead location and AV timing on cardiovascular performance has not been defined. This study tested the hypothesis that atrial pacing lead location can change the dependence of LA and LV hemodynamics on AV timing in vivo. Dogs anesthetized with isoflurane (n = 8) were instrumented for measurement of hemodynamics including LA pressure, LA volume, and pulmonary venous bloodflow. Data were recorded during normal sinus rhythm, and atrial overdrive pacing from the right atrial appendage (RAA), proximal coronary sinus (CS), and LA lateral wall (LAW). The AV node was then ablated and measurements repeated during synchronous ventricular pacing and during dual chamber pacing from each atrial lead location at various AV delays (20, 60, 120, 180, 240, and 350 ms). Hemodynamics during intrinsic sinus rhythm and overdrive atrial pacing from different sites were similar. In contrast, ventricular or dual chamber pacing caused significant (P < 0.05) changes in cardiac output with different AV timing during RAA (3.5 +/- 0.2 vs 2.9 +/- 0.2 L/min at 120 and 350 ms, respectively) and LAW pacing but not CS pacing. A significant interaction between atrial lead location and AV delay was observed for changes in stroke volume, pulmonary venous blood transport, LA volume, and LV preload. The results indicate that the atrial contribution to cardiac output depends on AV timing and atrial lead location in isoflurane-anesthetized dogs with AV nodal conduction block. 相似文献