Pulmonary veno-occlusive disease

Abstract

Pulmonary veno-occlusive disease (PVOD) is currently classified as a subgroup of pulmonary arterial hypertension (PAH) and accounts for 5-10% of cases initially considered to be idiopathic PAH. PVOD has been described as idiopathic or complicating other conditions, including connective tissue diseases, HIV infection, bone marrow transplantation, sarcoidosis and pulmonary Langerhans cell granulomatosis. PVOD shares broadly similar clinical presentation, genetic background and haemodynamic characteristics with PAH. Compared to PAH, PVOD is characterised by a higher male/female ratio, higher tobacco exposure, lower arterial oxygen tension at rest, lower diffusing capacity of the lung for carbon monoxide, and lower oxygen saturation nadir during the 6-min walk test. High-resolution computed tomography (HRCT) of the chest can be suggestive of PVOD in the presence of centrilobular ground-glass opacities, septal lines and lymph node enlargement. Similarly, occult alveolar haemorrhage is associated with PVOD. A noninvasive diagnostic approach using HRCT of the chest, arterial blood gases, pulmonary function tests and bronchoalveolar lavage could be helpful for the detection of PVOD patients and in avoiding high-risk surgical lung biopsy for histological confirmation. PVOD is characterised by a poor prognosis and the possibility of developing severe pulmonary oedema with specific PAH therapy. Lung transplantation is the treatment of choice. Cautious use of specific PAH therapy can, however, be helpful in some patients.KEYWORDS: Alveolar haemorrhage, BMPR2, computed tomography, diffusing capacity of the lung for carbon monoxide, pulmonary arterial hypertension, pulmonary veno-occlusive disease P ulmonary arterial hypertension (PAH) is a severe condition characterised by elevated pulmonary artery pressure leading to right heart failure and death [1,2]. Pulmonary veno-occlusive disease (PVOD) is classified as a subgroup of PAH and accounts for 5-10% of histological forms of cases initially considered to be idiopathic PAH. Even though the first welldocumented case of PVOD was described .70 yrs ago, the characteristics and pathophysiology of this disease remain poorly understood [3,4]. While pulmonary vascular pathology of idiopathic or familial PAH is characterised by a major remodelling of small pre-capillary pulmonary arteries with typical plexiform and/or thrombotic lesions, PVOD preferentially affects the post-capillary venous pulmonary vessels [5,6]. Despite this anatomical histological difference, PVOD has a very similar clinical presentation to PAH but is characterised by a worse prognosis and the possibility that severe pulmonary oedema can develop with specific PAH therapy, justifying the importance of diagnosing this disease. A definitive diagnosis of PVOD requires histological analysis of a lung sample [7,8]; however, surgical lung biopsy is a high-risk procedure in these patients and the development of a less invasive diagnostic approach would be preferable [9][10][11]. The present manuscript will summa...

Pulmonary Hypertension Complicating Multiple Myeloma

“…There is a higher-than-average incidence of venous thromboembolism (VTE) in patients with MM. 26 Immunomodulatory agentbased regimens, which may impair endogenous anticoagulation, are associated with an even higher risk of VTE in these patients. 27 Despite an increased incidence of pulmonary embolism, chronic thromboembolic PH (CTEPH) has not been commonly reported in the MM population.…”

Ventilation/perfusion lung scan in pulmonary veno-occlusive disease

“…Pulmonary angiography revealed attenuation of peripheral pulmonary arteries without radiological signs of chronic thromboembolic disease. DISCUSSION PVOD is a rare and severe condition with a poor prognosis that requires an early diagnosis because of the need for specific management, including high-dose diuretics, careful management of specific PAH therapy and early referral for lung transplantation [11,13,23,24]. The main risk for these patients is the development of acute pulmonary oedema with the use of PAH-specific drugs (prostacyclin, prostacyclin analogues, endothelin receptor antagonists or phosphodiesterase-5 inhibitors), which may promote fluid extravasation from the capillaries to the alveolus by acting mainly as arteriolar vasodilators against a venular obstruction due to specific remodelling [8,12,13].…”

“…The definitive diagnosis of PVOD requires histological examination of lung tissue samples. As lung biopsy is a high-risk procedure in the setting of PAH, it is not recommended, and histological proof of PVOD is usually retrospectively obtained after death or lung transplantation [8,11]. Therefore, a reliable noninvasive approach is needed for the diagnosis of PVOD.…”

“…However, lung biopsy for histological confirmation of PVOD is a high-risk procedure and therefore it is not recommended [11]. We have recently demonstrated that a noninvasive approach, including suggestive findings on high-resolution computed tomography (HRCT) of the chest, diffusing capacity of the lung for carbon monoxide (DL,CO) and bronchoalveolar lavage, can be helpful to screen for PVOD patients [8,15,16].…”

“…One of the prominent changes of the recent guidelines was to move pulmonary veno-occlusive disease (PVOD) and pulmonary capillary haemangiomatosis from separate categories into a single subcategory of PAH (group 19) [2]. PVOD is a rare form of PAH that remains poorly understood and is both difficult to diagnose and treat [6][7][8][9][10][11]. PVOD shares many similarities with idiopathic PAH, in particular, clinical features and haemodynamic characteristics, and therefore it can be difficult to distinguish PVOD from idiopathic PAH [8].…”