RESUMO
BACKGROUND: Contact-force (CF) sensing catheters are increasingly used in electrophysiological procedures due to their efficacy and safety profile. As data about the accuracy of fiberoptic CF technology are scarce, we sought to quantify it using in vitro experiments. METHODS AND RESULTS: A force sensor was built with a flexible membrane to allow exact reference force measurements for each set of experiments. A TactiCath Quartz (TCQ) ablation catheter was brought in contact with the force sensor membrane in order to compare the TCQ force measurements to sensor reference force measurements. Measurements were performed at different tip angles (0°/perpendicular contact, 45°, 90°/parallel contact), with fluid irrigation, different degrees of catheter deflection, and using a sheath. The accuracy of the TCQ force measurements was 0.9 ± 0.9 g (0°), 0.8 ± 0.8 g (45°) and 1.2 ± 1.3 g (90°), 0.8 ± 0.7 g (irrigation), 0.8 ± 0.8 g (deflection), and 0.8 ± 0.9 g (sheath); this was not significantly different among all experimental conditions. The precision was ≤3.8%. CONCLUSION: CF measurements using a fiberoptic sensing technology show a high level of accuracy and precision, without being significantly influenced by tip angle, fluid irrigation, catheter deflection or use of a sheath.
Assuntos
Cateterismo Cardíaco/instrumentação , Cateteres Cardíacos , Técnicas Eletrofisiológicas Cardíacas/instrumentação , Tecnologia de Fibra Óptica/instrumentação , Transdutores de Pressão , Calibragem , Cateterismo Cardíaco/normas , Cateteres Cardíacos/normas , Técnicas Eletrofisiológicas Cardíacas/normas , Desenho de Equipamento , Tecnologia de Fibra Óptica/normas , Teste de Materiais , Padrões de Referência , Reprodutibilidade dos Testes , Irrigação Terapêutica , Transdutores de Pressão/normasRESUMO
BACKGROUND: Robotic catheter navigation and ablation either with magnetic catheter driving or with electromechanical guidance have emerged in the recent years for the treatment of atrial fibrillation. OBJECTIVE: The aim of this study was to compare our center's experience of atrial fibrillation ablation using the Hansen Robotic Medical System with our current manual ablation technique in terms of acute and chronic success, as well as procedure time and radiation exposure to both the patient and the operator. METHODS: A total of 390 consecutive patients with symptomatic and drug-resistant atrial fibrillation (289 males, 62 +/- 11 years) were prospectively enrolled in the study. All patients underwent the procedure either with conventional manual ablation (group 1, n = 197) or with the robotic navigation system (RNS) (group 2, n = 193). RESULTS: The success rate for RNS was 85% (164 patients), while for manual ablation it was 81% (159 patients) (p = 0.264) at 14.1 +/- 1.3 months with AADs previously ineffective. Fluoroscopy time was significantly lower for RNS (48.9 +/- 24.6 minutes for RNS vs. 58.4 +/- 20.1 minutes for manual ablation, P < 0.001). Mean fluoroscopy time was statistically reduced after 50 procedures (61.8 +/- 23.2 minutes for first 50 cases vs. 44.5 +/- 23.6 minutes for subsequent procedures, P < 0.0001). CONCLUSION: Robotic navigation and ablation of atrial fibrillation is safe and effective. Fluoroscopy time decreases with experience.
Assuntos
Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Mapeamento Potencial de Superfície Corporal/métodos , Ablação por Cateter/métodos , Robótica/métodos , Cirurgia Assistida por Computador/métodos , Fibrilação Atrial/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Texas/epidemiologia , Resultado do TratamentoAssuntos
Ablação por Cateter , Traumatismos Cardíacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fibrilação Atrial/cirurgia , Fibrilação Atrial/fisiopatologia , Ablação por Cateter/efeitos adversos , Traumatismos Cardíacos/etiologia , Traumatismos Cardíacos/diagnóstico por imagem , Traumatismos Cardíacos/cirurgia , Resultado do TratamentoRESUMO
Bovine red blood cells (bRBCs) can potentially provide a simplistic and economic means of improving oxygenation within hollow fiber (HF) bioreactor cell cultures. Bovine RBCs are also interesting since many of their physical properties can be altered as a result of glutaraldehyde (G) cross-linking. Cross-linking bRBCs produces an oxygen carrier that is expected to be beneficial under specific circumstances (i.e., delivery of oxygen to cells that are sensitive to free hemoglobin (Hb) and cells that require low inlet oxygen tensions). We have examined the osmotic stability and electrophoretic mobility of cross-linked bRBCs and observed that cross-linking improves osmotic stability while minimally impacting electrophoretic mobility. The oxygen binding/dissociation properties (P(50) and n) of cross-linked bRBCs were also measured, and under the reported reaction conditions, cross-linking increased the oxygen affinity and reduced the cooperativity of bRBCs. A basic Krogh tissue cylinder model was then utilized to provide a quick a priori estimate of oxygen delivery and release to hepatocytes housed within a HF bioreactor in order to demonstrate potential oxygenation benefits arising with both normal and cross-linked bRBC media supplementation. This model showed that bRBCs generally improved oxygen delivery and release to HF cell cultures and that cross-linked bRBCs are particularly beneficial in specifically targeting oxygen delivery to cells maintained at low inlet oxygen tensions. Additionally, the model showed that bRBC supplementation can significantly improve oxygen delivery without requiring extreme bRBC concentrations.