Treatment of Bronchial Severe Asthma With Bronchial Thermoplasty. Assessment of Efficacy and Safety of Treatment, Study of Effects on Neuronal and Chemosensitive Component of the Bronchial Mucosa Pre and Post Treatment
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 12
- 试验地点
- 2
- 主要终点
- analysis of the risk and benefit profile with questionnaire ACT and AQLQ
研究概览
简要总结
In severe bronchial asthma the mechanism of inflammation and bronchospasm is complex and still not clarified. The smooth muscle cells play an important role from the mechanical point of view, as a culmination of neurogenic stimuli and inflammatory cytokines that determine as final effect the bronchospasm and over time a hypertrophy of the muscular coat. There are some other hypothesis that the smooth muscle cells may play a role as central regulator of chemical mediators that cause bronchospasm and inflammation, although there are currently no firm conclusions 2 According to other studies3,the nerve receptors TRANSIENT RECEPTOR POTENTIAL VANILLOID TYPE 1 have a great importance in the complex mechanism of airway inflammation too. (There are at least 4)
These receptors would intervene according to the following mechanism:
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Irritants on the bronchial mucosa stimulate the TRANSIENT RECEPTOR POTENTIAL VANILLOID TYPE 1 present on afferent endings of sensory fibers, unmyelinated C (chemiosensitive neurons)
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On the same afferent axon acting factors with the activation effect (lowering the activation threshold, increase the expression, promote the translocation of TRPV1 receptor on the membrane). Among these factors the neurotrophins of which the most important NERVE GROWTH FACTOR (NGF)
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The activation of TRPV1 (through release of Ca2 + +) determines two efferent responses:
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CENTRALLY-MEDIATED
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LOCAL AXON Reflex
Investigators hypothesized that BT may have a strong influence on the destruction of nerve receptors TRPV1 and unmyelinated nerve fibers located in the mucosa going to stop reflections both central and local authorities responsible for the activation of bronchospasm. In support of this hypothesis, there are some anatomical studies4, which show that these receptors are more numerous at the level of main bronchi which are the main target of BT. Please note in this context that it is already known that in thermoablations commonly used in cardiology it is used a radio frequency with development of heat controlled to 65 °, as in the BT, able to interrupt the circuit nervous responsible for the activation of the circuit causing the abnormal 'arrhythmia.
详细描述
The mechanism of action the bronchial thermoplasty exerts the positive action demonstrated by the studies through is not yet well understood yet. The only action on the denaturation and destruction of the smooth muscle layer of the bronchi at intermediate and high caliber perhaps not fully explain its action, taking into account that most of the smooth muscle loading of the small airways is minimally altered by the procedure. From the premises outlined in the section on the mechanism of inflammation we hypothesized that BT may have a strong influence on the destruction of nerve receptors TRPV1 and unmyelinated nerve fibers located in the mucosa going to stop reflections both central and local authorities responsible for the activation of bronchospasm. In support of this hypothesis, there are some anatomical studies4, which show that these receptors are more numerous at the level of main bronchi which are the main target of BT. Please note in this context that it is already known that in thermoablations commonly used in cardiology it is used a radio frequency with development of heat controlled to 65 °, as in the BT, able to interrupt the circuit nervous responsible for the activation of the circuit causing the abnormal 'arrhythmia.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Basic Science
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Patient with severe persistent asthma uncontrolled found in stable for at least 3 weeks
- •Patient receiving regular treatment with inhaled corticosteroids (beclomethason> 1000 mcg or equivalent) and LABA (salmeterol> = 100 mcg or equivalent)
- •AQLQ score <6.25
- •FEV1> = 60% predicted
- •Patients not smoking for at least one year
排除标准
- •acute asthma with life threatening
- •concomitant respiratory diseases (eg, COPD or emphysema)
- •use of ß-blocker drugs
- •severe active infection in the last 2 weeks
- •Pacemaker, internal defibrillator or other implanted electronic device.
- •Known sensitivity to medications used to perform bronchoscopy, including lidocaine, atropine and benzodiazepines.
- •Currently known bleeding disorder is not well controlled.
- •Inability to stop prior to the procedure taking anticoagulants, antiplatelet agents, aspirin or non-steroidal anti-inflammatory drugs
- •Pregnant women
结局指标
主要结局
analysis of the risk and benefit profile with questionnaire ACT and AQLQ
时间窗: Change from Baseline in ACT and AQLQ Questionaire one year after the end of the procedure
Evaluation of symptom control through the questionnaire ACT (ASTHMA CONTROL TEST) and AQLQ (Asthma quality life Questionaire) according to GINA criteria. The questionnaires AQLQ and ACT will be collected 3 months before the TB, the day before the procedure, and 3, 6, 12 months after the end of the procedure.
次要结局
- Analyze the changes in the state of innervation and nerve receptors before and after BT on histological samples of the bronchial mucosa(biopsies every 4 weeks( during the treatment))