Emphysema Surgery in 2026
A UK Surgeon's Perspective

1. Why surgery for emphysema?

Emphysema is a structural problem before it is a physiological one. Loss of elastic recoil, destruction of alveolar walls, and progressive airway collapse during expiration produce hyperinflation — air trapped behind dynamic obstruction that the patient cannot fully exhale. The clinical consequence is breathlessness disproportionate to the degree of airflow obstruction measured by FEV1 alone, because the work of breathing is dominated not by airflow resistance but by the mechanical disadvantage of operating at unfavourable lung volumes. Patients with severe disease breathe at lung volumes close to total lung capacity, with little room to expand on inspiration; their accessory muscles are recruited at rest, and the diaphragm — flattened and shortened by chronic hyperinflation — generates progressively less inspiratory force.

This is the pathophysiology that lung volume reduction addresses. Whether by surgical resection, bronchoscopic deflation, or transplantation, the principle is the same: remove or deflate the most diseased portion of the lung so that healthier tissue can re-expand into normal mechanical position. The diaphragm recovers length and curvature. The chest wall returns to a more efficient configuration. The work of breathing falls. Exercise tolerance improves before any change in spirometry is detectable, because the gain is mechanical before it is obstructive.

The BODE index [1] formalised what experienced clinicians had long observed: that mortality and disability in COPD are not predicted by FEV1 alone, but by a composite of body mass index, airflow obstruction, dyspnoea, and exercise capacity. The patients who benefit from lung volume reduction sit at the high-risk end of the BODE spectrum — significantly hyperinflated, breathless on minimal exertion, exercise-limited despite optimal medical therapy and pulmonary rehabilitation. They are not yet at the end of life. They are a population that has plateaued: optimised, rehabilitated, and still significantly disabled.

The size of the unreferred population

Estimates of the size of this population vary, but UK lung cancer screening data has now made them concrete. The Yorkshire Lung Screening Trial reported that 17% of ever-smokers aged 55–74 attending for low-dose CT screening had undiagnosed airflow obstruction with respiratory symptoms [2]. The SUMMIT cohort in London produced a comparable figure of 19.7% [3]. Of those, a substantial subset have severe disease, visible emphysema on CT, and the kind of phenotype that warrants specialist multidisciplinary review. The challenge, in 2026, is no longer identifying these patients. The challenge is moving them from a primary care result letter to a structured surgical and bronchoscopic assessment.

This is where many UK pathways still break down. A patient identified by screening, told they have COPD with emphysema, optimised on inhaled therapy, and offered pulmonary rehabilitation — and then, when breathlessness persists, told there is nothing more to do — has not yet had the assessment that would determine whether they are an LVR candidate. The phrase repeated most frequently in the second-opinion clinic at London Bridge Hospital is some version of I was told there was nothing more that could be done. In a meaningful proportion of those patients, that is not correct. It reflects the absence of a specialist surgical opinion in the pathway, not the absence of an effective option.

The remainder of this piece is an answer to that absence. The evidence base is mature. The selection framework is objective. The interventions work in the right patients — and in the correctly selected patient, lung volume reduction surgery is not only symptom-relieving but life-extending compared with continued medical therapy [7, 29, 30]. What is needed is the pathway that reliably delivers it.

2. The historical arc — Brantigan, Cooper, NETT

Brantigan, 1957

The principle of lung volume reduction is not new. Otto Brantigan and Edward Mueller proposed and operated on it in the 1950s, publishing their concept in American Surgeon in 1957 [4]. Their reasoning was mechanical: that resecting 20–30% of the most diseased lung tissue would restore radial traction on the small airways, recover diaphragmatic function, and relieve expiratory obstruction. Of 89 patients evaluated for surgery, Brantigan operated on 56, fourteen of them bilaterally. About three-quarters showed clinical improvement. The operation was abandoned, however, because the perioperative mortality — reported variously as 15–20% in series of that era — was unsupportable, and because the era's measurement tools could not objectively document the functional gains the surgeons were claiming. Brantigan's idea outlived him. His protocol did not.

Cooper revival, 1990s

The operation was revived almost forty years later by Joel Cooper at Washington University in St Louis. Cooper's 1995 paper described bilateral lung volume reduction performed via median sternotomy with linear staplers and bovine pericardial buttressing. The 1996 follow-up reported on 150 consecutive bilateral procedures performed between January 1993 and February 1996: ninety-day mortality of 4%, FEV1 improvement of 51% at six months, residual volume reduction of 28%, and 70% of patients who had previously been oxygen-dependent no longer requiring supplemental oxygen [5]. The 250-patient long-term follow-up published by Ciccone in 2003 confirmed durable benefit at five years in carefully selected patients. Cooper had done two things Brantigan could not: he had selected patients more rigorously, and he had measured outcomes that the spirometry of the 1990s could capture objectively.

NETT, 2001 and 2003

This was the evidence base on which the National Emphysema Treatment Trial was designed. NETT was the largest randomised trial in the field's history — 1,218 patients with severe emphysema enrolled at seventeen US centres, randomised to bilateral LVRS plus pulmonary rehabilitation versus pulmonary rehabilitation alone. Two NETT publications shaped the next two decades.

The first was the 2001 high-risk subgroup paper [6]. In April–May 2001, an interim analysis identified a group of 140 patients (13.6% of those enrolled at that point) defined by FEV1 ≤20% predicted and either DLCO ≤20% predicted or homogeneous emphysema on CT. In this subgroup, thirty-day surgical mortality was 16%, and survivors showed little chance of clinically meaningful improvement in lung function, exercise tolerance, or quality of life. The Data and Safety Monitoring Board terminated enrolment of this subgroup in May 2001. Long-term follow-up published more than a decade later showed that surgical patients in this high-risk subgroup ultimately achieved comparable outcomes to medical patients — but the early mortality penalty was the headline that endured.

The second was the 2003 main results paper [7]. Across the entire non-high-risk cohort of 1,078 patients there was no overall survival advantage from LVRS, with thirty-day surgical mortality of 2.2% versus 0.2% for medical therapy. The critical finding came from subgroup analysis. In 290 patients with upper-lobe predominant emphysema and low baseline exercise capacity, LVRS reduced the risk of death compared with medical therapy (relative risk 0.47, P = 0.005) — alongside significant improvements in exercise tolerance and quality of life. This subgroup, defined by CT phenotype and a single exercise-capacity threshold, became the canonical responder population. The mirror-image finding mattered just as much: in patients with non-upper-lobe emphysema and high baseline exercise capacity, mortality was higher with surgery than with medical therapy (RR 2.06, P = 0.02). NETT therefore did two things simultaneously: it confirmed that lung volume reduction extends life in the right patients, and it identified the wrong patients with enough precision that they could be excluded prospectively.

The survival evidence: NETT, long-term follow-up, and the Lim reanalysis

The survival evidence deserves direct attention because it is the strongest case for LVRS in correctly selected patients. The original 2003 NETT subgroup finding was that LVRS reduced the risk of death in 290 patients with upper-lobe predominant emphysema and low baseline exercise capacity, with a relative risk of 0.47 at median 2.4 years follow-up compared with continued medical therapy (P = 0.005) [7]. The long-term NETT follow-up published by Naunheim and colleagues in 2006 confirmed durability: at median 4.3 years the survival advantage in this subgroup was sustained (RR 0.57, P = 0.01) [29]. Extended follow-up of the high-risk subgroup itself showed that surgical patients ultimately achieved comparable long-term outcomes to medical patients despite the early mortality penalty that had prompted the 2001 stopping decision (NETT Research Group long-term follow-up, PMID 25201722). Eric Lim and colleagues at Royal Brompton subsequently reanalysed the NETT dataset using mixed-effects longitudinal modelling, providing more accurate long-term outcome interpretation than the original NETT analyses had achieved and reinforcing the survival case in the correctly selected phenotype [30]. Independent UK randomised evidence of LVRS efficacy was provided by the Royal Brompton's own 48-patient trial of LVRS versus medical therapy [32], with longitudinal mid-term reanalysis of the same cohort confirming durable functional and quality-of-life gain over medical care [31]; both trials were underpowered for mortality endpoints and corroborate the NETT functional finding rather than the survival finding. The convergent survival evidence — NETT main paper, NETT long-term follow-up, NETT extended high-risk follow-up, and the Lim 2020 longitudinal reanalysis — is what underpins the current Grade A recommendation for LVRS in the upper-lobe predominant, low-exercise-capacity phenotype in British Thoracic Society and European Respiratory Society COPD guidelines.

The post-NETT decline

The post-NETT trajectory in the United States was, paradoxically, decline rather than expansion. The high-risk subgroup analysis became the dominant headline. Operative mortality figures from the high-risk arm were quoted as if they applied to the procedure generally. Centres without dedicated programmes withdrew from offering LVRS, and case volumes fell sharply through the 2000s. By 2010 the operation was widely described as a "vanishing operation". The lessons of NETT — that selection was the variable, not the operation — were filed under a generalised reluctance.

Two developments since then have changed the picture. The first was the emergence of endobronchial valve therapy as a less invasive alternative for the Chartis-negative phenotype, covered in the next section. The second was the demonstration, by a small number of European programmes, that LVRS performed with modern selection, minimally invasive technique, and structured perioperative care yields outcomes that bear no resemblance to the post-NETT narrative. The recent UZ Leuven cohort — 248 elective LVRS procedures performed between August 2019 and November 2024, all by VATS, all without conversion to open surgery — illustrates the change of magnitude [8, 9]. That work is detailed in Section 5.

The historical arc, in summary, is one of an idea ahead of its measurement instruments, then ahead of its selection criteria, and finally — in the post-EBV era — ahead of the assumption that surgery cannot be justified given a less invasive alternative. Each generation of trial has answered a different question. The current generation answers how to integrate the two surviving modalities in a single MDT-led pathway.

3. Patient selection — the modern framework

Question 1 · Severity and fitness

Captured by the BODE index [1]: body mass index, airflow obstruction (FEV1), dyspnoea (mMRC), and exercise capacity (6-minute walk distance). The patients in scope sit in the moderate-to-severe BODE range — typically FEV1 between 20% and 45% predicted, mMRC ≥2 on optimal therapy, 6-minute walk distance preserved enough to complete pulmonary rehabilitation but constrained by breathlessness rather than other limitations. Patients below the FEV1 ≤20% threshold paired with low DLCO or homogeneous disease are the NETT high-risk phenotype and require especially careful evaluation; patients above the FEV1 50% threshold typically do not derive sufficient benefit to justify procedural risk. Patients deemed unfit for surgery elsewhere — often on the basis of a single FEV1 figure — are routinely re-assessed at GSTT against the structured pre-operative pathway set out on the fitness for lung surgery page; in a meaningful proportion the original verdict is revised once V/Q SPECT-CT, CPET, and split-function calculations are in hand.

Question 2 · Hyperinflation

Lung volume reduction works by relieving hyperinflation. If the patient is breathless primarily from gas exchange impairment — low DLCO, hypoxaemia, hypercapnia — without significant hyperinflation, deflating a lobe will not deliver mechanical benefit. The static lung volumes that matter are residual volume (RV) above approximately 150% predicted and total lung capacity (TLC) above approximately 100% predicted. RV/TLC ratio above 0.6 is a useful supplementary criterion. These are measured by body plethysmography, not estimated from spirometry; centres without on-site plethysmography refer for these measurements as part of the workup.

Question 3 · Imaging phenotype

High-resolution CT is read for the distribution of emphysema. Heterogeneous, upper-lobe predominant disease — one part of the lung dramatically more diseased than the rest — is the classical responder phenotype identified by NETT and confirmed by every subsequent trial. Heterogeneous disease in other distributions (lower-lobe, paraseptal) can also be treatable, with selection caveats. Homogeneous disease is more difficult: LVRS is generally not appropriate, and EBV is offered under stricter criteria supported by the IMPACT trial [10]. V/Q SPECT-CT adds functional information to the structural read, identifying the lobe with the worst ventilation–perfusion mismatch and confirming that the radiological target is also the functional target. Some patients with apparently homogeneous disease on CT prove to have a clear functional target on V/Q SPECT-CT, and become candidates by that route.

Question 4 · Collateral ventilation (the EBV/LVRS divider)

The Chartis Pulmonary Assessment System is a balloon catheter passed through a bronchoscope that measures airflow from the target lobe over five to ten minutes. If air continues to flow out from the lobe after the bronchus is occluded, collateral ventilation is present: there are pathways — usually through incomplete fissures — that bypass the normal airway. EBV will not deflate a lobe with collateral ventilation, because the lobe is being filled from elsewhere [11]. A patient with collateral ventilation either receives LVRS (where intact fissures are not required), receives no intervention, or — in selected patients with heterogeneous disease — is considered for AeriSeal CONVERT-style fissure closure followed by EBV (in the context of a clinical trial; see Section 7).

The decision matrix

Phenotype on CT	Chartis status	Canonical recommendation
Heterogeneous	Negative (no CV)	Endobronchial valve therapy
Heterogeneous	Positive (CV present)	Lung volume reduction surgery
Homogeneous, with V/Q target	Negative (no CV)	EBV under IMPACT criteria
Homogeneous, no V/Q target	—	Medical optimisation ± transplant assessment
Severe co-morbidity / no clear target	—	Continued medical therapy ± transplant assessment

The decision is made at MDT, not in clinic, and is documented in a structured letter to the referring clinician. The selection framework is what separates a procedure that delivers a survival benefit from one that delivers no benefit or harm. The trials that defined the field — VENT, STELVIO, LIBERATE, CELEB — each contributed a refinement to it. The next section sets out how that refinement happened.

4. Endobronchial valve therapy

VENT and the lesson it taught

The first major randomised trial of endobronchial valve therapy was VENT [12]. Sciurba and colleagues randomised 321 patients with severe heterogeneous emphysema in a 2:1 allocation to Zephyr endobronchial valve placement or standard medical care. The primary endpoints — change in FEV1 and 6-minute walk distance at 6 months — favoured the EBV group, but the magnitude of benefit was modest, the heterogeneity of response was substantial, and the safety signal — pneumothorax, valve migration, post-procedure infection — was non-trivial. VENT was, in publication terms, a positive trial. It was not, in clinical terms, a sufficient one to establish EBV as standard therapy.

The lesson from VENT, however, transformed the field. Post-hoc analysis identified collateral ventilation — measured by the completeness of interlobar fissures on CT — as the dominant predictor of response. Patients with intact fissures showed substantial benefit. Patients with incomplete fissures showed little or none. The mechanism was straightforward: a target lobe could only deflate if it could not be re-filled through collateral pathways. VENT thus did not establish EBV; it established the selection variable that would.

The pivotal trial arc

The UK refinement — Pallav Shah's group

Pallav Shah's group at Royal Brompton and Imperial published a series of UK trials applying tighter criteria, including the BeLieVeR-HIFi study, which randomised heterogeneous emphysema patients with intact fissures (the prospective equivalent of the VENT collateral-ventilation-negative subgroup) and demonstrated significant FEV1 improvement, walking distance gains, and quality-of-life benefit at 3 months [16]. TRANSFORM, the first multicentre European RCT applying Chartis-based selection prospectively, replicated the STELVIO findings in a larger patient population, with a primary endpoint of clinically meaningful FEV1 improvement at three months [17]. Kemp and colleagues, again from Royal Brompton and Imperial with Pallav Shah as co-author, demonstrated that the proportion of patients reaching the responder threshold was several times higher in the EBV arm than in standard care.

LIBERATE outcomes — the pivotal numbers

All sustained through 12 months of follow-up. FDA approval of the Pulmonx Zephyr valve followed in 2018, and the trial underpins the current NICE recommendation in the UK (HealthTech Guidance HTG457, published December 2017, replacing the earlier IPG465 and IPG600 guidance) [18].

CELEB: reframing the question

The CELEB trial answered the question that the published EBV evidence base could not, because the EBV trials all used medical therapy as the comparator: how does EBV compare with LVRS in patients suitable for either? Buttery and colleagues, on behalf of a five-centre UK consortium, randomised 88 patients with heterogeneous emphysema and intact fissures to LVRS or EBV [15]. The primary endpoint was the i-BODE composite (incremental shuttle walk test–based BODE) at 12 months. The two arms produced statistically and clinically similar improvements on i-BODE and its components. Length of stay was substantially shorter for EBV (median 3 days versus 9 days for LVRS). Re-intervention was more common in the EBV arm. Mortality was low and equivalent. CELEB therefore reframed the clinical question. EBV and LVRS are not competing modalities; they are complementary modalities, with the choice driven by phenotype rather than preference.

The pneumothorax question

The pneumothorax risk after EBV deserves direct mention. An expected post-procedure pneumothorax — caused by the rapid deflation of the target lobe and consequent pleural pressure imbalance — occurs in approximately one in four patients in published series and in our own GSTT and London Bridge Hospital experience. It is a known and anticipated event rather than a complication, and is managed routinely with a chest drain. Most resolve within 2–7 days. Its predictability is the reason patients are kept inpatient for 2–3 days after the procedure — early detection is straightforward, treatment is standard, and operator experience matters in the management of the small subset whose pneumothorax does not resolve with simple drainage. Mr Okiror is the sole EBV operator at GSTT and at London Bridge Hospital and has performed over 100 combined EBV and LVRS interventions since the GSTT programme began in 2019.

EBV for persistent air leak — the second clinical application

Endobronchial valves have a second clinical application that is conceptually different from lung volume reduction but mechanically related. The valves can be placed bronchoscopically in the airway segment supplying a persistent air leak from a bronchopleural fistula. Once that segment is occluded, the air leak typically resolves immediately, allowing chest drain removal and faster recovery.

The clinical situations in which this matters are three. First, patients with persistent post-surgical air leak — typically following pulmonary resection — where conventional management has failed. Second, patients with persistent air leak complicating spontaneous or secondary spontaneous pneumothorax, often on a background of bullous emphysema or COPD: the underlying disease overlaps substantially with the lung volume reduction population. Third, critically ill patients with severe parenchymal lung disease in whom surgery would carry an unacceptable risk; the canonical example being patients with COVID-19 ARDS on veno-venous extracorporeal membrane oxygenation (VV-ECMO).

The clinical pattern across the persistent air leak population is consistent with the lung volume reduction population: many of these patients have underlying bullous emphysema or significant COPD, and many of them — once the acute air leak is resolved — also benefit from formal lung volume reduction assessment. The two clinical applications of the same device sit on the same patient population at different points in the disease trajectory.

Surgical and critical care teams in the United Arab Emirates, Southampton, and Aberdeen have consulted Mr Okiror on the management of complex persistent air leak cases. He has been an invited speaker on bronchoscopic valve technique to UK and European thoracic units, including teaching sessions at North Tees NHS Foundation Trust.

5. Lung volume reduction surgery — the modern era

The Leuven evidence

The narrative of LVRS in the United States since NETT has been one of contraction. National case volumes fell through the 2000s as centres without high-volume programmes withdrew from offering the procedure. By the 2010s, with EBV emerging as a less invasive alternative, US LVRS volumes were a fraction of their late-1990s peak. The narrative in select European programmes has been different.

The most prominent of these is UZ Leuven, where Laurens Ceulemans and colleagues operate one of Europe's largest LVRS programmes, integrated with a high-volume lung transplantation service. The 2025 paper in Interdisciplinary CardioVascular and Thoracic Surgery by Vandervelde, Ceulemans and colleagues reports 248 elective LVRS procedures performed between August 2019 and November 2024 — all by VATS, all without conversion to open surgery [8]. The 2026 paper in the European Respiratory Journal extends the analysis across emphysema morphologies and explicitly argues, in the language of the abstract, that "a quarter of a century after NETT" the perception of LVRS as a high-mortality, narrow-indication procedure is "outdated" [9]. The Leuven cohort includes patients beyond conventional NETT criteria — patients NETT would have excluded — with operative outcomes that justify the expansion of eligibility. Earlier work from the same broader research group had already demonstrated that LVRS is feasible and beneficial in homogeneous emphysema [20], directly challenging the homogeneous-disease exclusion that NETT had embedded into general practice.

What is different in modern Leuven practice

Three things are different in the modern Leuven programme:

• Selection — supported by the same imaging, lung function, and bronchoscopic assessments that govern EBV selection, with the additional advantage that LVRS does not require absence of collateral ventilation.
• Technique — entirely thoracoscopic, no median sternotomy, with stapling and pleural management protocols refined over high case volume.
• Perioperative pathway — structured preoperative pulmonary rehabilitation, anaesthetic protocols designed for severe emphysema (avoiding high airway pressures, preserving lung-protective ventilation through one-lung anaesthesia), and a dedicated thoracic ward team trained in the post-LVRS recovery pattern.

Outcomes that look implausibly good in publication are achievable when all three elements are aligned, and impossible to reproduce when any one is missing.

The June 2025 GSTT immersion

In June 2025, Mr Okiror led the GSTT LVRS multidisciplinary team — the lead respiratory physician, the charge nurse, and the lead thoracic physiotherapist — to UZ Leuven for clinical immersion. The visit ran for several days, with observation of theatre cases, ward rounds, MDT discussions, and the perioperative pathway end-to-end. The objective was not to import the Leuven protocol wholesale — the patient mix, anaesthetic cultures, and institutional contexts differ — but to identify which elements of the Leuven approach were responsible for the published outcomes and which were translatable to GSTT and London Bridge Hospital. Several refinements to selection thresholds, anaesthetic approach, and post-operative ward protocols followed. A prospective before-and-after audit is currently underway at GSTT, comparing outcomes pre- and post-Leuven across the same patient categories. Findings will be reported in due course.

EBV and LVRS as complementary, not competing

The relationship between EBV and LVRS in the modern pathway is no longer one of competing modalities, as CELEB confirmed [15]. It is one of phenotype-matched complementarity: Chartis-negative heterogeneous patients to EBV, Chartis-positive heterogeneous patients to LVRS, with selected homogeneous patients to either depending on V/Q SPECT-CT findings. In a unit that offers both, the question is no longer which procedure to favour — it is which patient phenotype is in front of you. The CELEB length-of-stay difference (median 3 days for EBV versus 9 days for LVRS) and re-intervention rate (higher with EBV) are the practical considerations that follow phenotype, not the basis for choosing between them.

GSTT performs both procedures with the same operator, the same MDT, and the same perioperative team. Mr Okiror is the sole EBV operator at GSTT and the sole operator for both EBV and LVRS at London Bridge Hospital. Combined EBV/LVRS volume since the GSTT programme began in 2019 stands at 100+ interventions. The audit that began following the Leuven visit will, when matured, allow GSTT to publish outcomes against the Leuven and US benchmarks; the absence of published outcome figures here is deliberate, pending audit completion.

The historical claim that LVRS is a high-mortality procedure with limited benefit reflects the post-NETT US experience, not modern European practice. In appropriately selected patients, LVRS delivers a survival benefit over medical therapy alongside durable functional and quality-of-life gain — the case originally established in the NETT upper-lobe predominant, low-exercise-capacity subgroup (RR 0.47 at median 2.4 years, P = 0.005) [7], sustained at long-term follow-up (RR 0.57 at median 4.3 years) [29], and reinforced by Eric Lim's longitudinal reanalysis [30]. Modern programmes operating on the right phenotype achieve this with low operative mortality. The challenge in the UK is not technical. It is pathway design — referral, MDT assessment, and the operational discipline of running a programme that handles enough cases to maintain the volume-outcome relationship.

6. Modalities considered, and why EBV won

A clinician-facing piece on emphysema surgery would be incomplete without reckoning with the modalities that did not survive into modern practice. Three are worth covering, because the reasons they failed illuminate why EBV did succeed.

The Spiration valve

Spiration intrabronchial valves were a competing valve technology to Pulmonx Zephyr, with a different umbrella-shaped design. A series of trials demonstrated efficacy comparable to early Zephyr studies, but the commercial trajectory diverged: the Spiration valve was withdrawn from the emphysema indication and is now marketed for a more limited set of post-surgical air leak applications.

The pattern across all four

The pattern across all four — coils, vapour, bypass stents, Spiration — is that modest efficacy could not survive the comparison with a modality that worked better. EBV won not because the alternatives were ineffective, but because none of them produced the magnitude of durable benefit that LIBERATE secured for Zephyr in the Chartis-selected population. The Chartis biomarker is, in retrospect, what separated EBV's pathway from the others. Selection was the difference. It always is.

7. AeriSeal — the collateral-ventilation-positive question

The unanswered question in the modern EBV pathway is what to do with the heterogeneous emphysema patient whose Chartis assessment indicates collateral ventilation. Such patients have the right phenotype on imaging, the right physiology on testing, and the right symptoms — but the device that would otherwise help them cannot deflate the target lobe. They are the EBV-ineligible group that LVRS exists to serve.

For patients in whom LVRS is also not feasible — or who decline it — there is an emerging alternative that addresses the collateral ventilation problem directly. The AeriSeal system (originally developed by Aeris Therapeutics, now owned by Pulmonx) delivers a polymeric foam bronchoscopically into the segments of the target lobe abutting the incomplete fissure. The foam triggers a localised fibrotic response that occludes the collateral pathways, converting the lobe from CV-positive to CV-negative. Once converted, the patient can be treated with conventional Zephyr endobronchial valves.

The first-generation AeriSeal trials in the early 2010s were terminated for safety concerns, and the original Aeris Therapeutics business folded shortly afterwards. Pulmonx subsequently acquired the technology and redeveloped it with revised delivery protocols. The CONVERT study (NCT04559464) was a single-arm feasibility trial completed in the early 2020s; it demonstrated that the conversion principle worked — CV-positive patients could be reliably converted to CV-negative, and could then receive valve therapy with outcomes comparable to those of natively CV-negative patients [26].

CONVERT-II (NCT06035120) is the current pivotal trial. It is a multicentre, international, single-arm study planned to enrol up to 200 patients with heterogeneous emphysema and confirmed collateral ventilation in the target lobe. Patients are treated first with AeriSeal and then, if conversion is achieved at a 45-day Chartis re-assessment, with Zephyr valves. Primary endpoints relate to FEV1 improvement at six months. Findings from CONVERT-II will support a pre-market approval application to the FDA. The trial is currently recruiting at approximately 30 sites across the United States, Europe, and Australia.

GSTT is not currently a CONVERT-II site, and Mr Okiror is not a CONVERT-II investigator. The technology is not yet available for clinical use outside the trial. Patients in whom CONVERT-style sealant therapy might apply are currently directed to LVRS where appropriate or to continued medical optimisation pending pivotal trial outcomes.

8. Lung transplantation for emphysema

Lung transplantation is the option considered when lung volume reduction will not deliver sufficient benefit, when disease severity exceeds what LVR can address, or when the patient's functional trajectory is one of inexorable decline that EBV or LVRS will not reverse.

The ISHLT registry view

The International Society for Heart and Lung Transplantation (ISHLT) registry is the most authoritative source of outcome data in the field. The 2022 ISHLT Adult Lung Transplant Report focused specifically on COPD and emphysema recipients [27]. Several findings shape the modern conversation. First, COPD is no longer the dominant indication for lung transplantation — it has been overtaken in volume by interstitial lung disease, reflecting both the success of EBV/LVRS in deflecting selected COPD patients away from transplant and the rising incidence of fibrotic lung disease in transplant-eligible age ranges. Second, recipients with COPD are now older at transplant than in earlier eras, are more likely to be on mechanical ventilation or hospitalised at the time of transplant, and carry more comorbidities. Third, post-transplant median survival in COPD recipients is competitive with the natural history of severe medically-managed emphysema, but requires careful patient selection given the lifetime implications of immunosuppression.

The ISHLT registry was suspended from 2018 to 2024 because of evolving European privacy regulations. The 2025 report, the first comprehensive new data from the registry since the relaunch, broadly confirms the trends described in the 2022 COPD-focused report, with refinements reflecting changing practice in donor and recipient management since 2018.

The UK transplant landscape

UK transplantation for emphysema is concentrated in five centres: Royal Brompton and Harefield (the largest single UK volume), Newcastle, Manchester (Wythenshawe), Birmingham, and Papworth. The proximity of Harefield to Guy's and St Thomas' — and the integration of a Harefield lung transplantation physician and surgeon into the monthly GSTT emphysema MDT, described in Section 9 — means that for patients managed at GSTT, the question of transplant candidacy is asked formally in the same room as EBV and LVRS. This is uncommon. Most UK lung volume reduction services discuss EBV and LVRS in one MDT and refer onward to a separate transplant assessment if and when the lung volume reduction options are exhausted. The structural problem with that pathway is well documented: many patients who would have benefited from earlier transplant assessment are referred too late, when comorbidity burden, deconditioning, or hospitalisation have foreclosed transplant candidacy.

The integration at GSTT means a 60-year-old patient with severe heterogeneous emphysema, BODE in the high range, and significant functional decline is considered for all four options — medical optimisation, EBV, LVRS, transplant assessment — at the same MDT. Some patients receive EBV with a documented plan to revisit transplant candidacy if EBV does not deliver durable benefit. Some are listed for transplant assessment immediately. Some have transplant ruled out at the discussion (typically on grounds of age, comorbidity, or psychosocial factors) but receive EBV or LVRS as the appropriate alternative. The recommendation is documented in a structured letter to the referring clinician.

The integration is operationally simple. The clinical effect is significant: transplant assessment becomes a parallel option rather than a downstream referral, and patients who would benefit from transplant listing are identified earlier in the trajectory, when they are still good transplant candidates.

9. The integrated multidisciplinary model

MDT composition

Most UK LVR centres have respiratory physicians, COPD clinical nurse specialists, thoracic radiologists, nuclear medicine input, and a thoracic surgeon. The GSTT MDT has all of these, plus — and this is the structural difference — the standing presence of a lung transplantation physician and surgeon from Harefield Hospital. They attend the monthly meeting and participate in every case discussion. Patients are not "referred onward" to a separate transplant clinic; their transplant candidacy is reviewed in the same room, at the same time, by the team that would be responsible for transplant listing if it were the right answer. This eliminates the deferred-assessment failure mode that, in less-integrated services, leads to late transplant referrals from patients who have already lost transplant candidacy through deconditioning or comorbidity progression.

The four-option discipline

The second structural feature is the rule that no patient is referred to a single option without all options having been considered. The MDT discussion considers, for every patient, continued medical optimisation, EBV, LVRS, transplant assessment, and (where relevant) clinical trial enrolment. The default is not "this patient needs treatment X." The default is "what is the right answer for this patient, having considered all four pathways, and can we document the reasoning in a way that survives onward review?"

The discipline matters because the four pathways differ not only in symptom relief but in life expectancy. For the patient with the right phenotype, LVRS extends life compared with continued medical therapy [7, 29, 30]. For the wrong patient — the NETT non-upper-lobe, high-exercise-capacity phenotype, or the high-risk subgroup that NETT identified prospectively — operating shortens life. The MDT exists to ensure that the survival-benefiting phenotype is identified and offered LVRS, the survival-decrementing phenotype is excluded from surgery and offered an appropriate alternative, and the patient between them is matched to the modality that best serves them.

Documentation discipline

The MDT conclusion is documented in a structured letter to the referring clinician within days of the meeting. The letter records the recommendation, the supporting evidence (CT phenotype, lung function, V/Q SPECT-CT findings, Chartis result), and the proposed timing of intervention if intervention is indicated. The patient receives parallel correspondence and is offered direct contact with the team for questions. This level of documentation is operationally heavier than the typical UK LVR pathway, but it is what allows the team to justify the recommendation to subsequent reviewers — second-opinion clinicians, insurers, and the patient themselves.

The combination of integrated transplant input and the four-option discipline is what most distinguishes the GSTT emphysema service from comparator UK centres. Both elements are operationally simple to describe. Both are difficult to implement and harder to sustain, because they depend on protected MDT time, willing transplant centre engagement, and a referral pathway that brings patients in early enough to allow the four-option discussion to be substantive.

For private patients managed at London Bridge Hospital, the same MDT discipline applies. Cases are discussed at the GSTT MDT, with the same transplant input and the same documentation standards, regardless of the funding route. Mr Okiror is the operator across both NHS and private settings; the MDT, the perioperative pathway, and the post-procedure follow-up are unified.

10. Practice in 2026 — UK NHS and private pathways

NHS commissioning and private pathway

Endobronchial valve therapy and lung volume reduction surgery are both available on the NHS at the centres nationally commissioned by NHS England for the Advanced Emphysema Surgical Service. Guy's and St Thomas' is one of these commissioned centres. Mr Okiror is the sole designated EBV operator at GSTT and the sole operator for both EBV and LVRS at London Bridge Hospital, where he runs his private practice. Combined EBV and LVRS volume since the GSTT programme began in 2019 exceeds 100 interventions.

NHS waiting times from referral to MDT and intervention are typically 4–6 months — driven by capacity and the referral catchment, not by indication. Private appointments at London Bridge Hospital are typically available within 2–3 working days. Days, rather than months, separate completed workup from intervention in the private pathway. The same operator, the same MDT discussion, and the same post-procedure follow-up apply across both settings.

Where treatment takes place

For straightforward EBV cases in well-selected patients, treatment can also be delivered at The Lister Hospital Chelsea. For complex LVRS cases, and for patients with significant comorbidities or severe gas trapping, surgery takes place at London Bridge Hospital, where the level of intensive care, respiratory medicine, and bronchoscopy support matches the complexity of the patient. Outpatient consultations are also available at HCA outpatients in Canary Wharf and the City of London. Same-day or next-day virtual consultations can be arranged for patients in other regions or internationally.

A clinician's perspective — SCTS 2026 Belfast

Referral pathway

Referrals can be made directly to the practice. A brief referral letter with recent spirometry, CT chest report, and current inhaled therapy is sufficient. Static lung volumes and Chartis assessment are arranged as part of the workup at the specialist centre; they are not required before referral.

Patients self-referring for second opinion — typically because they have been told elsewhere that no further treatment is possible — are seen on the same timescale as referred patients. The second-opinion service exists because the most common reason a patient with severe emphysema is told there is nothing more to do is the absence of a specialist surgical opinion in the pathway, not the absence of an effective option. For the patient with the right phenotype, the absent option is one that has been shown in randomised data — confirmed at long-term follow-up and on independent reanalysis — to extend life compared with continued medical therapy, not just to improve symptoms [7, 29, 30]. Where a second-opinion review concludes that intervention is genuinely not appropriate, that conclusion is documented in the same structured letter that any MDT recommendation receives, with the supporting reasoning, so that the patient and the referring clinician can understand why.

Bullectomy — a related but distinct procedure

Bullectomy — the surgical removal of a single dominant bulla — is distinct from the diffuse parenchymal disease that lung volume reduction addresses. The two procedures are sometimes confused. Indications for bullectomy include both breathlessness from a compressing bulla and complications such as recurrent pneumothorax, infection, haemoptysis, chest pain, or suspected cancer in or adjacent to a bulla. Patients whose dominant clinical problem is a single bulla — whether presenting with breathlessness from compression, recurrent pneumothorax, or as an incidental finding — are managed under that pathway rather than the lung volume reduction MDT.

Summary

The principle of lung volume reduction — relieving hyperinflation by removing or deflating the most diseased lung — was articulated by Brantigan in the 1950s, refined by Cooper in the 1990s, validated and constrained by NETT in the 2000s, and extended to a less invasive bronchoscopic modality through the EBV trials of the 2010s. The current era is one of phenotype-matched complementarity: Chartis-negative patients to EBV, Chartis-positive heterogeneous patients to LVRS, selected homogeneous patients to either depending on V/Q SPECT-CT findings, and lung transplantation considered in the same MDT discussion rather than as a downstream referral.

In appropriately selected patients — heterogeneous, upper-lobe predominant emphysema with low baseline exercise capacity — LVRS delivers a survival benefit over continued medical therapy that has been demonstrated in randomised data (NETT 2003, RR 0.47, P = 0.005) [7], sustained at long-term follow-up (RR 0.57 at median 4.3 years, P = 0.01) [29], and confirmed by Eric Lim's independent statistical reanalysis using mixed-effects longitudinal modelling [30]. This is the strongest argument for the procedure and the most important framing of what the modern UK service is for: not symptomatic relief alone, but life-extension in the patient phenotype where the evidence supports it. The selection framework set out in Section 3 is the apparatus that finds those patients.

The evidence base supporting the modern pathway is mature: VENT [12] established the principle and identified collateral ventilation as the selection variable; STELVIO [13] operationalised the variable through Chartis; LIBERATE [14] secured pivotal evidence and FDA approval; CELEB [15] confirmed parity with surgery. The Leuven LVRS programme has demonstrated that the post-NETT high-mortality narrative is outdated when modern selection, technique, and perioperative care are in place [9]. NICE recommendation HTG457 governs UK practice; NHS England commissions the Advanced Emphysema Surgical Service at designated centres including GSTT.

The challenge in the UK in 2026 is not evidence, technology, or clinical pathway. It is referral. A meaningful proportion of patients eligible for EBV or LVRS are never referred — typically because they are managed in pathways that do not include specialist surgical opinion, or because the verdict "no further options" is reached without MDT review. For the patient who would have benefited from LVRS in the right phenotype, that absence is not just a missed quality-of-life opportunity; it is a missed survival benefit. The screening pipeline is closing one part of that gap. Pathway design at the receiving end — including service models that integrate transplant input and use four-option MDT discipline — is what closes the rest.

References

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