A Bronchoscopic Steam Thermal Ablation (BTVA) Case Report in A 85-Year-Old Male Clinically Compromised

Background: Bronchoscopic lung volume reduction (BLVR) techniques improve lung function and increase exercise tolerance in patients with chronic obstructive pulmonary disease (COPD) and BLVR treatment is included in the Global Initiative for Chronic Obstructive Lung Disease (GOLD) treatment guidelines for these patients. BTVA (Intervapor Uptake Medical, Tustin, CA, USA) represents a recent therapy of this group that allows to treat sublobar areas and for this reason is used clinically compromised patients, like in this case report. Case presentation: In this paper we describe a case report of an 85-year-old male with severe respiratory failure and a diagnosis of emphysema presented with dyspnea and clinical worsening, despite the best medical therapy practiced. For comorbidity and pathology’s features he was excluded from surgical treatment options, like lung volume reduction surgical (LVRS) and from positioning of endobronchial valves (EBV) for the presence of collateral ventilation and he was addressed to BTVA. The procedure was successful for this patient. Conclusions: This case supports recent suggestions that BTVA can be a good alternative treatment for patients properly selected.

Background BLVR treatment is included in the GOLD treatment guidelines for COPD patients (1). The most used devices are endobronchial valves (EBV) (2,3,4), used for the rst time in 2002, but this treatment is reserved to patients with emphysema with no collateral ventilation (CV) and integrity of the interlobar ssures (IF) at the chest computed tomography (CT). For emphysematous patients without these features there are alternative devices (5,6). BTVA (Intervapor Uptake Medical, Tustin, CA, USA) represents a recent alternative therapy for these patients that uses high temperature water vapor to induce parenchymal thermal damage and in ammation resulting in brosis and volume reduction in the treated area, independently from interlobar CV (7,8,9).

Case Presentation
An 85-year-old male was admitted to our clinic (April 2019) with diagnosis of COPD (GOLD D). He had a history of arterial blood hypertension and hyperuricemia. A family history of lung tumor (brother), nor of drug allergies. He was a former smoker of 60 pack years (stop smoking 20 years prior). He had important dyspnea at rest (mMRC > 3) despite optimal pharmacotherapy (aclidinium bromide and salmeterolo/ uticasone) two times daily, teo lline, prednisone as needed and continuous 6 L/min of oxygen.
Pulmonary function test (PFT): ratio of forced expiratory volume in 1 s (FEV1) to forced vital capacity (FVC) was 51%, FEV1 was 1.29 L (percentage of predicted FEV1, 56%), residual volume (RV) was 3.96 L (percentage of predicted RV, 140%); the total lung capacity (TLC) was 7.50 L (percentage of predicted TLC, 118%), and the percentage of predicted diffusing capacity of carbon monoxide (DLCO) was 21%. In order to perform BLVR, the CT scan was analyzed by a dedicated software (VIDA Diagnostics, Coralville, IA, USA) measuring disease severity of each segment for identify the target area. The software showed a difference in lung density between targeted UL segment and its respective lower lobe and absence of IF. For this reason, LVRS and EBV weren't taken into consideration and BTVA was proposed as an alternative.
After placing an endoscopic catheter, a balloon was in ated in order to occlude the target segment and water heated vapor was delivered, 8.5 cal/g dose, rst in LB1 + 2a for 6.1 s. Afterwards the balloon was de ated and the catheter was inserted into the other sub-segmentary bronchus LB1 + 2b for 3.6 s to complete the treatment of LB 1 + 2 a -b (Figs. 2).
The total procedure time was about 10 min. The treatment was performed in rigid bronchoscopy under general anesthesia, in order to suppress the cough that could displaced the balloon.
After the procedure an increase in the in ammatory markers (PCR 5.48 mg/dl vs 0.5 mg/dl at admission, PCT 0.13 µg/L vs 0.02 µg/L) was found.
The CT scan performed after BTVA (Figs. 3) showed a parenchymal pulmonary in ammatory response of the apicodorsal segment of the left UL, with consequent reduction of lung volume (10). No adverse events were recorded (11). The patient was discharged at home in post operative day 8. BTVA represents a valid alternative to EBV that allows to treat only the most damaged lung segments of patients with heterogeneous emphysema. In 2009, Snell et al (12,13) proposed the use of BTVA. STEP-UP is the most important randomized, controlled open label trial (14,15), that shows signi cant difference in FEV1 and SGRQ at 6 and 12 months (16). In this trial patient have a mean FEV1 of 33% and a mean VR of 235% and undergone to a rst treatment of 1 emphysematous segment of an upper lobe and then of one emphysematous segments in the contralateral upper lobe after 12 weeks. After 6 months there were statistically signi cant difference in FEV1 and SGRQ. Data obtained at the 12-month follow-up visits showed persistent improvements in lung function relative to baseline. While Gompelmann et al (17,18) have emphasized that patients should have 20%>FEV1 < 45% of predicted values, RV > 175% of predicted values and DLCO ≥20% of predicted values and the patient had higher FEV1 and lower RV values, the outcome of the procedure was excellent.
As helium dilution technique was used to perform PFT, it's possible that RV values are underestimated compared to the same values calculated with plethysmography. This suggest that is important use the latter technique to perform PFT.
Despite we treat only sub-segmentary bronchus LB 1 + 2a-b, because of the patient critical issue, an extraordinary result has been achieved.
This case supports recent suggestions that BTVA can result in a good alternative treatment for patients properly selected and that minimally invasive treatments are an important resource in managing compromised patients. This is a case report that and not require approval by the institute's committee on human research.

Consent for publication
The patient has given written informed consent to publish this case (including publication of images).

Availability of data and materials
Data sharing is not applicable to this article as no datasets were generated or analysed during the current study.

Competing interests
The authors declare that they have no competing interests.

Funding
The authors declare that they have no funding