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61.
Thomas C. Crawford Alan Wimmer Sujoya Dey Nagib Chalfoun Darryl Wells Jean-Francois Sarrazin Michael Kuhne Melissa Frederick Krit Jongnarangsin Eric Good Aman Chugh Frank Bogun Frank Pelosi Jr. Fred Morady Hakan Oral 《Journal of interventional cardiac electrophysiology》2008,21(1):27-33
Background A better understanding of the mechanisms of recurrent atrial fibrillation (AF) after radiofrequency ablation of complex, fractionated
atrial electrograms (CFAEs) may be helpful for refining AF ablation strategies.
Methods and results Electrogram-guided ablation (EGA) was repeated in 30 consecutive patients (mean age = 59 ± 8 years) for recurrent paroxysmal
AF, 10 ± 4 months after the first ablation. During the first procedure, CFAEs were targeted without isolating all pulmonary
veins (PVs). During repeat ablation, all PVs and the superior vena cava (SVC) were mapped with a circular catheter and the
left atrium was mapped for CFAEs. EGA was performed until AF was rendered noninducible or all identified CFAEs were eliminated.
During repeat ablation, ≥1 PV tachycardia was found in 83 PVs in 29 of the 30 patients (97%). Among these 83 PVs, 63 (76%)
had not been completely isolated previously. During repeat ablation, drivers originating in a PV or PV antrum were identified
only after infusion of isoproterenol (20 μg/min) in 12 patients (40%). At 9 ± 4 months of follow-up after the repeat ablation
procedure, 21 of the 30 patients (70%) were free from recurrent AF and flutter without antiarrhythmic drugs.
Conclusions Recurrence of AF after EGA is usually due to PV tachycardias. Therefore, it may be preferable to systematically map and isolate
all PVs during the first procedure. High-dose isoproterenol may be helpful to identify AF drivers. 相似文献
62.
63.
Amrish Deshmukh MD John Larson MD Michael Ghannam MD Mohammed Saeed MD Ryan Cunnane MD Hamid Ghanbari MD Rakesh Latchamsetty MD Thomas Crawford MD Krit Jongnarangsin MD Frank Pelosi Jr. MD Aman Chugh MD Hakan Oral MD Fred Morady MD Frank Bogun MD Jackson J. Liang DO 《Journal of cardiovascular electrophysiology》2021,32(12):3173-3178
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66.
Groups of rats on commercial diet were injected 3,000 IU (group 2) and 7,500 IU (group 3) of vitamin D3 on the 10th day of pregnancy. Compared to control pups (group 1), the pups in group 2 and 3 weighed significantly more on the 10th, 20th and 28th day of age. At 28th day of age, study of the gastrocnemius muscle revealed significantly greater organ weight, protein, DNA and RNA contents, protein/DNA and RNA/DNA ratios in group 2 and 3 pups than in controls. In the liver, whereas all these indices were significantly increased in group 3 pups, only protein/DNA and RNA/DNA ratios were significantly increased in group 2 pups. Brain weight, its RNA content and RNA/DNA ratio were significantly greater in group 2 and 3 pups than in controls. The results suggest that vitamin D administration in pregnancy promotes soft tissue growth in the pups by enhancing cellular proliferation and hypertrophy. 相似文献
67.
Ranjith Tellis Olga Starobinets Michael Prokle Usha Nandini Raghavan Christopher Hall Tammana Chugh Ekin Koker Siva Chaitanya Chaduvula Christoph Wald Sebastian Flacke 《Journal of digital imaging》2021,34(1):75
Identifying areas for workflow improvement and growth is essential for an interventional radiology (IR) department to stay competitive. Deployment of traditional methods such as Lean and Six Sigma helped in reducing the waste in workflows at a strategic level. However, achieving efficient workflow needs both strategic and tactical approaches. Uncertainties about patient arrivals, staff availability, and variability in procedure durations pose hindrances to efficient workflow and lead to delayed patient care and staff overtime. We present an alternative approach to address both tactical and strategic needs using discrete event simulation (DES) and simulation based optimization methods. A comprehensive digital model of the patient workflow in a hospital-based IR department was modeled based on expert interviews with the incumbent personnel and analysis of 192 days’ worth of electronic medical record (EMR) data. Patient arrival patterns and process times were derived from 4393 individual patient appointments. Exactly 196 unique procedures were modeled, each with its own process time distribution and rule-based procedure-room mapping. Dynamic staff schedules for interventional radiologists, technologists, and nurses were incorporated in the model. Stochastic model simulation runs revealed the resource “computed tomography (CT) suite” as the major workflow bottleneck during the morning hours. This insight compelled the radiology department leadership to re-assign time blocks on a diagnostic CT scanner to the IR group. Moreover, this approach helped identify opportunities for additional appointments at times of lower diagnostic scanner utilization. Demand for interventional service from Outpatients during late hours of the day required the facility to extend hours of operations. Simulation-based optimization methods were used to model a new staff schedule, stretching the existing pool of resources to support the additional 2.5 h of daily operation. In conclusion, this study illustrates that the combination of workflow modeling, stochastic simulations, and optimization techniques is a viable and effective approach for identifying workflow inefficiencies and discovering and validating improvement options through what-if scenario testing. 相似文献
68.
Vishnu Prasad Pulappadi Smita Manchanda Pritviraj SK Smriti Hari 《The British journal of radiology》2021,94(1117)
Corpus luteum rupture presenting as acute abdomen is an underdiagnosed condition. Though a self-limiting entity, its differentiation from other causes is essential to prevent unnecessary surgical procedures. The radiologist should be aware of the possibility of a ruptured haemorrhagic ovarian cyst in a female of reproductive age group presenting with pelvic pain and a large amount of haemorrhagic ascites. Imaging characteristically reveals a thick-walled cystic structure in the adnexa with internal echoes, focal discontinuity or irregularity of its wall with haemoperitoneum. While sonography is usually indicative of corpus luteum rupture, cross-sectional imaging (CT/MRI) can be used to confirm the diagnosis. 相似文献
69.
Renu Sharma Aditya N Aggarwal Shuchi Bhatt Sudhir Kumar SK Bhargava 《Indian Journal of Orthopaedics》2015,49(5):542-548
Background:
de Quervain''s tenosynovitis is an inflammation of abductor pollicis longus (APL) and extensor pollicis brevis (EPB) muscle tendon sheaths at the level of radial styloid process. Its conservative management includes nonsteroidal anti-inflammatory drugs, wrist and thumb immobilization, ultrasonic therapy (US Th.) and low level laser therapy (LLLT). Literature is scanty on comparative efficacy of US Th. and LLLT for its management. This prospective study evaluates outcome of US Th. versus LLLT in de Quervain''s disease.Materials and Methods:
Thirty patients clinically diagnosed de Quervains tenosynovitis were included in the study and randomly assigned to two groups. The average age was 36 years (range: 21-45 years). One group was given LLLT and the other US Th. for a total of 7 exposures on alternate days. The clinical criteria used were Finkelstein''s test, tenderness over radial styloid (Ritchie''s tenderness scale), grip strength, pain (visual analog scale [VAS]) and radiological criteria was ultrasonographic assessment of change in thickness of APL and EPB tendon sheath. They were measured before commencement and at the end of seven sessions of therapy, as per standard procedure.Results:
Significant improvement was seen within both groups in the following outcome measures assessed: Ritchie''s tenderness scale, grip strength and VAS. Finkelstein''s test was not significantly improved in either groups. Ultrasonographic measurement of tendon sheath diameters, the mediolateral (ML), and anteroposterior (AP) diameters was not found to be significantly different in the US Th. group and the laser therapy group after treatment. On comparing both the groups, no statistically significant difference was found. However, looking at the mean values, the grip strength and VAS showed better improvement in the US Th. group as compared to the laser therapy group. 相似文献70.
Nemandra Sandiford SK Muirhead-Allwood JA Skinner 《Indian Journal of Orthopaedics》2015,49(6):595-601