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Bronchial Thermoplasty and Guided Bronchoscopy Part Two Wes Shepherd, MD Director of Interventional Pulmonology Associate Professor of Pulmonary and Critical Care VCU Medical Center Bronchial thermoplasty: • “Reduction in airway hyperresponsiveness to methacholine by the application of RF energy in dogs” – 3 treated lung regions (55, 65, and 75 C) in 11 dogs (> 300 sites) – 65-75° C significantly reduced airway response (AR) to local methacholine challenge – AR inversely correlated to extent of smooth muscle alteration – Benefit persisted out to 3 years (no stenosis or anatomic deformity) J Appl Physiol 2004;97:1946-1953 Bronchial thermoplasty: • “A prospective feasibility study of bronchial thermoplasty in the human airway” (1st human study) – – – – – – – 9 patients undergoing lung resection for cancer (nonasthmatics) BT to segmental bronchi to be removed 1-3 weeks pre-op Activations at 55-65°C No adverse symptoms Post BT bronchoscopies showed no stenosis or scarring ASM replaced by loose connective tissue Surgical specimens examined showed reduced ASM (> in 65°C) • Epithelium – normal, sloughing, regenerative • Mucous ducts /glands – metaplasia • Cartilage – mild necrosis or new growth CHEST 2005;127:1999-2006 Bronchial thermoplasty: • “Asthma control during the year after bronchial thermoplasty” (AIR trial) – RCT in 4 countries – 112 moderate to severe persistent asthma age 18-65 • Worsening asthma control with LABA withdrawal X 2 weeks – On ICS and LABA with FEV1 6085% predicted – PC20 < 8 mg/ml on methacholine challenge – BT by moderate sedation or general anesthesia NEJM 2007;356:1327-37 Bronchial thermoplasty: • “Asthma control during the year after bronchial thermoplasty” (AIR trial) – Designed to show that BT patients had improved control when LABA withdrawn – Benefits also present at 3 months on ICS/LABA – Extrapolate to 10 fewer mild exacerbations/year and 86 additional symptom free days/year – Nonblinded – results probably beyond placebo effect – Adverse effects more common in treatment group immediately after procedure but similar from 6 weeks to 12 months • 6 hospitalizations (4 subjects – asthma exacerbation) NEJM 2007;356:1327-37 Bronchial thermoplasty: • “Asthma control during the year after bronchial thermoplasty” (AIR trial) – Primary outcome • Frequency of mild exacerbations (during LABA withdrawal for 2 weeks at 3,6,12 months) NEJM 2007;356:1327-37 Bronchial thermoplasty: • “Asthma control during the year after bronchial thermoplasty” (AIR trial) – Secondary outcomes • • • • • • • Airflow Asthma symptoms Airway responsiveness Symptom-free days Rescue medication use Asthma Quality of Life Questionnaire (AQLQ) Asthma Control Questionnaire (ACQ) NEJM 2007;356:1327-37 Bronchial thermoplasty: NEJM 2007;356:1327-37 Bronchial thermoplasty: NEJM 2007;356:1327-37 Bronchial thermoplasty: • “Safety and efficacy of bronchial thermoplasty in symptomatic severe asthma” – 32 patients with severe persistent asthma – Short term worsening of asthma symptoms – 4 of 15 in treatment group hospitalized during treatment period (2 had segmental collapse) – At 22 weeks BT group had significant improvements vs control group in: • Rescue medication use • Pre-bronchodilator FEV1 % predicted • Asthma control questionnaire Am J Respir Crit Care Med 2007;176:1185-91 AIR2 – Pivotal IDE Clinical Trial • Purpose: Pivotal US Investigational Device Exemption (IDE) Study to support indication for use in severe asthma • Sham controlled, double blinded • Study Population: • Severe persistent asthma (297 patients) • Symptomatic despite high dose ICS + LABA • Primary Endpoint: Asthma Quality of Life Questionnaire (AQLQ) score • Follow-up: One year • 5-year safety follow-up for BT subjects Bronchial Thermoplasty Clinical Outcomes at 1-Year • Improved asthma-related quality of life compared to control (AQLQ score) • 79% of BT treated patients achieved ≥ 0.5 increase • Effect persistent across 6, 9, and 12 months • Improved clinical outcomes compared to control: • • • • 32% decrease in severe exacerbations 84% reduction in ER visits for respiratory symptoms 73% reduction in hospitalization for respiratory symptoms 66% less days lost from work, school and other daily activities due to asthma • No unanticipated device-related adverse events or deaths • Acceptable safety profile Castro, Am J Respir Crit Care Med. 2010;181(2):116-24 Persistence of Effect at Two Years • Effectiveness of BT persists out to at least two years – proportion of patients experiencing severe exacerbations comparable between years 1 and 2 Castro M, et al. Ann Allergy Asthma Immunol. 2011 Jul;107(1):65-70. 13 Procedure Safety: • 850 bronchoscopies performed in patients with severe asthma (558 BT and 292 Sham procedures) • No device-related deaths or major adverse events • e.g., Pneumothorax, airway stenosis or focal narrowing • More respiratory adverse events were reported in the BT group in the shortterm after the procedure • Typically occurring within one day and resolving within one week with standard care • Fewer respiratory adverse events, hospitalizations and ER visits in the BT group during post-treatment perioda Castro, Am J Respir Crit Care Med. 2010;181(2):116-24 Respiratory Symptoms Resulting in Hospitalization Following Procedure BT (N=190) Sham (N=98) 19 Hospitalizations in 16 Subjects No. of Events (Incident Rate %) 2 Hospitalizations in 2 Subjects No. of Events (Incident Rate %) Asthma Aggravated 12 (6.3%) Atelectasis 3 (1.6%) Lower Resp. Tract Infection 1 (0.5%) Hemoptysis 1 (0.5%) Low FEV1 1 (0.5%) Aspirated Prosthetic Tooth in Airway 1 (0.5%) Asthma Aggravated Castro, Am J Respir Crit Care Med. 2010;181(2):116-24 2 (2.0%) Contraindications • Active respiratory infection • Asthma attack or changing dose of systemic corticosteroids (up or down) in the past 14 days • Recent severe asthma exacerbation • Known bleeding disorder • Patient is unable to stop taking anticoagulants, antiplatelet agents, aspirin or non-steroidal anti-inflammatory medications (NSAIDS) before the procedure with physician guidance 16 Post-Procedure/Patient Follow Up • Patient contacted via phone at 1, 2 and 7 days to assess post procedure status • Office visit at 2 to 3 weeks to assess clinical stability and schedule subsequent BT procedures as appropriate • Patient returns to care of primary asthma physician for long term asthma management following BT • Patient may be evaluated for step-down therapy to determine lowest level of medication necessary to maintain asthma control Long-Term Safety • 5 year follow-up in Feasibility, AIR Trials & 4 year follow-up in RISA trial: – Stable pulmonary function – No clinical complications based on AE reporting • Annual CT scans for 5 years (Feasibility Study): – All patients doing well – No clinically significant findings • BT treatment has excellent safety profile long-term 18 Long Term Data: AIR 2 • 162 of 190 (85%) of treated patients in AIR 2 followed 5 years • Safety: – No pneumothorax, intubation, arrhythmia, or death – No decrease in FEV1 – No structural changes in airway (HRCT) • Efficacy: – Reduction in severe exacerbations persisted – ED visits reduced 78% (vs 12 months prior to treatement) – No change in respiratory adverse events or respiratory hospitalizations in years 2-5 vs year 1 post BT J Allergy Clin Immunol 2013;132:1295-302 Long Term Data: AIR 2 J Allergy Clin Immunol 2013;132:1295-302 Procedure Reimbursement • CPT codes now category 1 effective January 1, 2013 • >230 sites nationwide • 10 sites in Virginia • Coverage policies and payment vary by payer – small number of insurance companies covering currently • Commercial payers starting to post positive coverage policies 21 Clinical Summary of Bronchial Thermoplasty • Despite a transient worsening of asthma – Typically occurring within one day and resolving within one week with standard care • Patients experience long term benefits out to at least one year: – Improvement in quality of life – Decrease in severe exacerbations – Decrease in ER visits – Decrease in days lost from work or school Castro, et. al. AJRCCM, 2010 22 Guided Bronchoscopy: • Virtual bronchoscopy (CT image only) • Virtual bronchoscopy navigation (Olympus, Broncus) • Electromagnetic navigational bronchoscopy (ENB) (Superdimension, Veran) • Radial EBUS (peripheral endobronchial ultrasound) • Ultrathin bronchoscopy • CT fluoroscopy bronchoscopy Guided Bronchoscopy: • Diagnostic: – Biopsy of peripheral pulmonary nodules – Biopsy of lymph nodes • Therapeutic: – Placement of fiducial markers for radiation – Marking (“tattooing”) nodules prior to surgical resection – Delivery of a therapeutic agent or device (chemo, cryo, etc) Guided Bronchoscopy: • Standard flexible bronchoscopy limited ability to reach peripheral lung nodules – Peripheral nodules < 20 mm • Outer third of lung yield = 14% • Central two-thirds yield = 31% • Yield higher if “bronchus sign” present on CT (uncommon in small lesions) CHEST 2000;117:1049-54 Electromagnetic Navigational Bronchoscopy: • • • • • “GPS” for the bronchial tree Uses CT 3-D data Radiologic and endobronchial mapping Electromagnetic guidance catheter in real time Extended working sheath to peripheral lesion for biopsy instruments Electromagnetic Navigational Bronchoscopy: • Planning (pre-procedure): – CT chest with or without contrast – DICOM on CD into system – Target selection – lesion center and at end of airway if possible – System creates 3D bronchial tree and “road map” : Electromagnetic Navigational Bronchoscopy: • Procedure: – Deep sedation/general anesthesia – Room set up – electromagnetic board – Load planning data into computer – Patient position and lead placement – Rapid on-site cytology – Fluoroscopy via C-arm on designated gurney – Bronchoscopy (therapeutic scope) • Routine airway exam • Registration done by driving bronchoscope into all lobes Electromagnetic Navigational Bronchoscopy: SuperDimension Electromagnetic Navigational Bronchoscopy: • “Electromagnetic navigation diagnostic bronchoscopy in peripheral lung lesions” CHEST 2007;131:1800-1805 Electromagnetic Navigational Bronchoscopy: • “Meta-analysis of guided bronchoscopy for the evaluation of the pulmonary nodule” – 39 studies met criteria (> 3000 patients) – Pooled diagnostic yield 70% – Pneumothorax 1.5% (chest tube 0.6%) Technology # Studies Weighted yield % Virtual Bronch 10 72.0 ENB 11 67.0 Guide Sheath 10 73.2 Ultrathin 11 70.0 R-EBUS 20 71.1 CHEST 2012;142(2):385-393 Electromagnetic Navigational Bronchoscopy: • “Multimodality Bronchoscopic Diagnosis of Peripheral Lung Lesions” – – – – – RCT of radial EBUS vs ENB vs both (120 patients) Combined – EBUS probe through EWC to confirm within lesion Forceps without fluoro Pneumothorax rates 5-8% Diagnostic yield: • Combined 88% • EBUS 69% • ENB 59% AJRCCM 2007;176:36-41