Long-term follow-up after bronchoscopic lung volume reduction treatment with coils in patients with severe emphysema

Abstract

Background and objective: Bronchoscopic lung volume reduction coil (LVR-coil) treatment has been shown to be safe and clinically effective in patients with severe emphysema in the short term; however, long-term safety and effectiveness has not been evaluated. The aim of this study was to investigate the long-term safety and effectiveness of LVR-coil treatment in patients with severe emphysema.

Methods: Thirty-eight patients with severe emphysema (median age is 59 years, forced expiratory volume in 1 s is 27% predicted) who were treated in LVR-coil clinical trials were invited for a voluntary annual visit. Safety was evaluated by chest X-ray and recording of adverse events and by efficacy by pulmonary function testing, 6-min walk distance (6MWD) and questionnaires.

Results: Thirty-five patients visited the hospital 1 year, 27 patients 2 years and 22 patients 3 years following coil placement. No coil migrations were observed on X-rays. At 1-year follow-up, all clinical outcomes significantly improved compared with baseline. At 2 years, residual volume % pred, modified Medical Research Council (mMRC) and the SGRQ score were still significantly improved. At 3 years, a significant improvement in mMRC score remained, with 40% of the patients reaching the 6MWD minimal important difference, and 59% for the St George's Respiratory Questionnaire (SGRQ) minimal important difference.

Conclusions: Follow-up of the patients treated with LVR-coils in our pilot studies showed that the coil treatment is safe with no late pneumothoraces, coil migrations or unexpected adverse events. Clinical benefit gradually declines over time; at 3 years post-treatment, around 50% of the patients maintained improvement in 6MWD, SGRQ and mMRC.

Clinical trial registration: NCT01220908 and NCT01328899 registered at ClinicalTrials.gov.

Keywords: bronchoscopy and interventional technique; clinical respiratory medicine; coil; emphysema; long-term follow-up.

© 2014 The Authors. Respirology published by Wiley Publishing Asia Pty Ltd on behalf of Asian Pacific Society of Respirology.

Figures

Figure 1

Flowchart of study participants. FU, follow-up; LVR, lung volume reduction.

Figure 2

The first X-ray after the procedure and last available follow-up X-ray of two example patients. (a) Directly after the procedure in patient 1. (b) Three years after the procedure in patient 1 without any changes. (c) Directly after the procedure in patient 2. (d) Three years after the procedure in patient 2, showing some ‘crowding’ of the coils in the left-upper lobe resulting in volume reduction and a better left hemi-diaphragm position.

Figure 3

Decline in forced expiratory volume in 1 s (FEV1) before and after the LVR-coil treatment. Baseline and post-treatment FEV1 shown as mean (±standard deviation). ‘’: before treatment; ‘’: trend line; ‘’: during study participation.

Figure 4

Histology of transplanted lungs of two patients (photomicrograph, haematoxylin and eosin stain). (a) Low power magnification of lung tissue demonstrating two device imprints (arrows) in the alveolar parenchyma. (b) Higher magnification of the boxed area in image (a) demonstrating the two device imprints in tissue. At this magnification, it is evident that there is a thin, compressed capsule of tissue around the imprints with no other significant inflammatory reaction present. This image also demonstrates the presence of interstitial fibrosis of alveolar septa along the left hand side of the image. (c) Higher magnification of the boxed area in image (b) demonstrating a closer view of the device capsule and the surrounding alveolar parenchyma. (d) Low power magnification of a single device imprint in the alveolar parenchyma (arrow). The imprint is surrounded by a well-organized fibrous capsule comprised of compressed, concentric rings of stroma. Pre-existing emphysema (enlarged alveolar spaces) is also evident in this image. (e) Low power magnification of a single device imprint (arrow) in the alveolar parenchyma adjacent to a pulmonary vein. (f) Low power magnification of a single device imprint in an area of more dense fibrous tissue. The device capsule contains a mild degree of inflammation. (a–c) Patient 1 year after LVR-coil treatment; (d–f) patient 4 years after LVR-coil treatment.