Ventilation/perfusion lung scan in pulmonary veno-occlusive disease

Abstract

Pulmonary veno-occlusive disease (PVOD), a rare form of pulmonary arterial hypertension (PAH), requires histological proof for definitive diagnosis; however, lung biopsy is not recommended in PAH. Recent conjoint European Respiratory Society/European Society of Cardiology guidelines suggest that nonmatched perfusion defects on ventilation/perfusion (V9/Q9) lung scanning in PAH patients may suggest PVOD. The aim of our study was to evaluate V9/Q9 lung scans in a large cohort of PVOD and idiopathic or heritable PAH patients.V9/Q9 lung scans from 70 patients with idiopathic or heritable PAH and 56 patients with confirmed or highly probable PVOD were reviewed in a double-blind manner.The vast majority of V9/Q9 lung scans were normal or without significant abnormalities in both groups. No differences in ventilation or perfusion lung scans were observed between PAH and PVOD patients (all p.0.05). Furthermore, no differences were observed between confirmed (n531) or highly probable PVOD (n525). Nonmatched perfusion defects were found in seven (10%) idiopathic PAH patients and four (7.1%) PVOD patients (p.0.05).Nonmatched perfusion defects were rarely seen in a large cohort of idiopathic or heritable PAH and PVOD patients. Future recommendations should be amended according to these results suggesting that V9/Q9 lung scanning is not useful in discriminating PVOD from idiopathic PAH.

2015 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension

“…In addition, their presence appears to closely correlate with the risk of pulmonary oedema with PAH drugs. V/Q lung scanning is not useful in discriminating PVOD/PCH from IPAH [377].…”

“…While CT pulmonary angiography is the investigation of choice for the diagnosis of acute PE, planar V/Q lung scan remains the main first-line imaging modality for CTEPH, as it carries a 96-97% sensitivity and a 90-95% specificity for the diagnosis [47]. In contrast, in IPAH and PVOD, perfusion scans typically show non-segmental defects or are normal [377]. More recent work suggests that both V/Q scanning and modern CT pulmonary angiography may be accurate methods for the detection of CTEPH, with excellent diagnostic efficacy in expert hands (100% sensitivity, 93.7% specificity and 96.5% accuracy for V/Q and 96.1%, 95.2% and 95.6%, respectively, for CT pulmonary angiography) [93,423,424].…”

2015 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension

“…Ponadto wydaje się, że ich obecność ściśle koreluje z ryzykiem obrzęku płuc w trakcie podania leków swoistych dla PAH. Scyntygrafia V/Q płuc nie jest pomocna w odróżnianiu PVOD/PCH od IPAH [377]. Ponieważ PVOD/PCH może przebiegać z niemymi klinicznie krwawieniami do pęcherzyków płucnych, bronchoskopia z płukaniem oskrzelowo-pęcherzykowym może być przydatnym narzędziem diagnostycznym.…”

Pulmonary hypertension nosography: are all patients classifiable?

“…PVOD shares many similarities with idiopathic PAH, in terms of clinical features and haemodynamic characteristics [8]. Their clinical presentation is non-specific, mainly characterised by dyspnoea, and they cannot be distinguished neither hemodynamically [9] or by perfusion lung scan [9,10]. However, PVOD has lower arterial oxygen tension, lower nadir oxygen saturation during exercise, and lower diffusing capacity for carbon monoxide and occult pulmonary haemorrhage with haemosiderin-laden macrophages at bronchoalveolar lavage [8,[11][12][13].…”