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51.
Endocardial catheter ablation of ventricular tachycardia in patients with ventricular assist devices
Gopi Dandamudi MD Waqas S. Ghumman MD Mithilesh K. Das MD John M. Miller MD 《Heart rhythm》2007,4(9):1165-1169
BACKGROUND: The outcomes of patients with ventricular assist devices (VADs) who undergo catheter ablation for ventricular tachycardia (VT) have not been reported. OBJECTIVE: The purpose of this study was to assess the feasibility, safety, and efficacy of endocardial VT ablation in patients with VADs. METHODS: We retrospectively reviewed three cases at our institution where endocardial catheter ablation was performed in patients with VADs and incessant VT. RESULTS: Three patients with underlying cardiomyopathies and VADs underwent VT ablation for incessant VT refractory to multiple antiarrhythmic medications. In each case, VT was either eliminated or significantly ameliorated by catheter ablation. No procedure-related complications occurred. The hemodynamic stability afforded by the VAD played an important role in facilitating ablation in two of the cases. CONCLUSION: Catheter ablation for VT in VAD patients appears to be feasible, safe, and effective based on our initial experience. Several technical issues, such as decreases in ventricular volumes that can limit maneuverability of the ablation catheter and potential entrapment of the mapping catheter in the inflow cannula, need to be considered at the time of ablation. 相似文献
52.
Sunny E Ohia S Olubusayo Awe Catherine A Opere Angela M LeDay Lydia C Harris Kaustubh Kulkarni Najam A Sharif 《Journal of ocular pharmacology and therapeutics》2003,19(6):599-609
The glucose deprivation-induced release of [3H]D-aspartate was studied in bovine and human retinas in a superfusion apparatus. [3H]D-aspartate release was significantly increased upon omitting glucose in the superfusion buffer. This effect was dependent on external Ca2+ because L- and N-type Ca2+-channel blockers, such as diltiazem (1 microM), nitrendipine (1 microM), and omega-conotoxin (100 nM), significantly reduced the effect of glucose-deprivation induced release of [3H]D-aspartate. Furthermore, while glutamate receptor agonists (L-glutamate, N-methyl-D-aspartate, but not kainate) potentiated the effects of glucose deprivation, antagonists (MK-801, MCPG, ifenprodil, and L-AP3) at these receptors blocked the glucose deprivation-induced release process. Taken together, these studies have demonstrated that under conditions of glucose deprivation, as may happen during ischemic events in vivo, the retinal glutamatergic nerve endings and/or glial cells promote the efflux of [3H]D-aspartate into the extracellular environment. This process appears to be receptor-mediated and dependent on extracellular Ca2+ and is similar to previous reports pertaining to brain tissues. 相似文献
53.
Nematode polyprotein allergens (NPA) are lipid binding/transport molecules that elicit elevated levels of IgE response in the infected host, leading to Th2 type of immune response. They also transport arachidonic acid and its metabolites that are known to be involved in the action of antifilarial drug, Diethylcarbamazine and hence are of great significance for the control of lymphatic filariasis. We investigated the polymorphism of gp15/400 polyprotein of 35 isolates of lymphatic filarial parasite Wuchereria bancrofti collected from different geographic locations of India. The repeat sub-unit of the gene was found to be highly conserved in all the isolates with only two nucleotide synonymous changes at positions 286 (A-G) and 337 (C-T). Since this molecule is highly conserved and has multifarious roles in the survival and pathogenesis of the parasite it has good potential as a target for drug, immunodulation tool and immunotherapy development. 相似文献
54.
P K Das A Manoharan S Subramanian K D Ramaiah S P Pani A R Rajavel P K Rajagopalan 《Epidemiology and infection》1992,108(3):483-493
An Integrated Vector Management (IVM) strategy was implemented from 1981 to 1985 in one part of Pondicherry, South India, for the control of the bancroftian filariasis vector Culex quinquefasciatus (the IVM area). The rest of the town (the comparison area) received the conventional larvicidal input. After 1985 both the areas were managed conventionally. The switch to conventional strategy resulted in an increase of vector density in both areas. The microfilaraemia prevalence in humans showed a general decline (P less than 0.05) from 1986 to 1989 only in the IVM area whereas its intensity did not change significantly in either area. While the age-specific rate of gain of infection was generally unchanged in the IVM area, an increase in all age classes was observed after 1985 in the comparison area, where the Annual Transmission Index was high during the previous years. In both areas the rate of loss of infection increased during 1986-9 compared to 1981-6. The results suggest that 3 years is too short a period to relate the changes in entomological parameters to those in the microfilaraemia status of the population. 相似文献
55.
V K Das 《International journal of pediatric otorhinolaryngology》1991,21(2):121-125
The study involves aetiological evaluation of various adverse perinatal causes leading to bilateral sensorineural hearing impairment in children born during the 5-year period of 1981-1985 (inclusive) in the Greater Manchester area of England, United Kingdom. This group comprised over 12% of the total number of hearing-impaired children in the area. Individual possible adverse factors are discussed in the light of present understanding of the pathogenesis and previous reports. 相似文献
56.
S K Brantley S F Davidson M B Johnson P A St Arnold S K Das 《Annals of plastic surgery》1990,25(1):44-47
Investigations into the effects of prior silicone exposure on subsequent capsule formation around silicone implants assume particular relevance in light of the exponential increase in the medical application of polymers such as silicone. The inert nature of silicone has been in question with regard to its effects on the immune system, specifically whether or not it may act as a hapten or antigen. The present study analyzes the effects of prior silicone exposure on subsequent capsule formation, histological consistency, and pressures when an animal is reexposed to a silicone implant. Twelve female Lewis rats (body weight 250 g) were randomly divided into two groups. Group 1 (n = 6) rats were subcutaneously injected with 2.5 ml of Freund's Complete Adjuvant, Group 2 (n = 6) rats were injected with an equal volume of adjuvant sonicated with silicone gel. At 4 weeks a gel-filled silicone implant was placed subcutaneously in each animal. Capsule pressures were obtained at 4 months and the capsules from 3 rats from Group 2 were excised and examined microscopically. Pressures were measured again at 8 months and all remaining capsules were excised and examined. No statistically significant differences were noted when comparing two profiles over time between silicone-exposed and nonexposed animals in regard to capsule thickness or capsule pressure. However, capsule pressures were significantly lower at 8 months than at 4 months in both groups (p less than 0.034). In this model, significant reductions in capsule pressure were noted in both groups over time, but prior exposure to silicone did not appear to alter capsule histology, thickness, or pressure. 相似文献
57.
A single 200-mg dose of clinafloxacin was given orally to each of nine healthy male volunteers, and the concentrations of the drug were measured in plasma, cantharidin-induced inflammatory fluid, and urine over the following 24 h (48 h in the case of urine). The mean maximum concentration in plasma was 1.34 μg/ml at a mean time of 1.8 h postdose. The mean maximum concentration in the inflammatory fluid was 1.3 μg/ml at 3.8 h postdose. The mean elimination half-life of clinafloxacin in plasma was 5.65 h. The overall penetration into the inflammatory fluid was 93.1%, as assessed by determining the ratio of area under the concentration-time curves. Recovery of clinafloxacin in urine was 58.8% by 24 h and 71.8% by 48 h postdose. 相似文献
58.
Cardiac injuries--a clinical and autopsy profile 总被引:3,自引:0,他引:3
P Kulshrestha B Das K S Iyer K A Sampath M L Sharma I M Rao P Venugopal 《The Journal of trauma》1990,30(2):203-207
One hundred two patients sustaining cardiac injuries over a 4-year period were analysed to highlight the natural history of the cardiac injuries. There were 45 blunt, 36 stab, and 21 gunshot injuries. The injury involved the ventricle in 85, atrium in seven, pulmonary artery in five cases, and resulted in crush injury to the heart in the remaining five cases. Thirty-three patients (32.3%) died on the scene and 58 (56.9%) died during the transportation. Only 11 patients (10.8%) reached the hospital alive, and ten of these patients survived following thoracotomy and repair of the cardiac injury. The factors influencing the natural course of cardiac injury were analysed: 2.2% of patients with blunt cardiac trauma reached the hospital alive compared to 19.4% with stab and 14.3% with gunshot injuries; ventricular injuries had a greater prehospital mortality compared to atrial or pulmonary artery injuries; 11.3% of patients sustaining injury to right ventricle reached the hospital alive compared to 3% of those with left ventricular injuries. These data emphasize the need for rapid transport, immediate recognition, and aggressive surgical management, to make a favourable impact on the natural history of cardiac injuries. 相似文献
59.
S Das 《Journal of the Indian Medical Association》1991,89(9):253-255
In 12 children colostomy wound closure was undertaken with liberal extraperitoneal mobilisation of the bowel. In all the cases adequate length of the colonic loops could be achieved for resection of the colostomy and end to end anastomosis. There was only minor wound infection in 3 cases. There was no faecal fistula nor any postoperative intestinal obstruction. 相似文献
60.
The external carotid artery (ECA) is an underestimated but important collateral to the cerebral hemisphere and eye in patients with severe disease of the internal carotid artery. Fifteen symptomatic patients with total occlusion of the internal carotid artery underwent ECA reconstruction. Ipsilateral ECA reconstruction was performed upon all patients with no mortality or neurologic deficits. Contralateral disease of the carotid artery was noted in 11 and required correction in seven patients. Follow-up study of the patients ranged from one to 68 months (a mean of 26.8 months) after operation. Vertebrobasilar symptoms persisted in two patients, both with contralateral disease. One of these patients successfully underwent extracranial-intracranial bypass. One ipsilateral and one contralateral stroke occurred during follow-up study, both in patients with contralateral disease. Eleven patients were alive and asymptomatic at last follow-up examination. Symptomatic selected patients with occlusion of the internal carotid artery and ECA stenosis or cul-de-sac formation should be considered for operation. ECA reconstruction is associated with little morbidity and three-fourths of the patients remain asymptomatic. A high incidence of contralateral disease of the carotid artery is present. Extracranial-intracranial bypass should only be considered when symptoms persist after correction of contralateral disease of the carotid artery and any ECA lesions. 相似文献