Pulmonary hypertension associated with sarcoidosis: mechanisms, haemodynamics and prognosis

Sarcoidosis with pulmonary hypertension exacerbated by Takayasu-like large vessel vasculitis

A 72-year-old male visited the hospital with a complaint of dyspnea. Under the diagnosis of pulmonary hypertension (PH) due to chronic thrombotic and/or embolic disease, this patient received anti-coagulant therapy. Unfortunately, the respiratory state deteriorated and died 34 days after admission. At autopsy, noncaseating granulomas, which were diagnostic of sarcoidosis, were found in bilateral enlarged hilar lymph nodes, lungs, heart, liver, spleen, testis and epididymis. In pulmonary vasculature, the following three kinds of lesions were observed; (i) sarcoid granulomatous vasculitis at the peripheral arteries and veins, (ii) intimal fibrous lesions ubiquitously found in proximal and peripheral arteries which were thought to be organized thromboemboli, (iii) Takayasu-like large vessel vasculitis with a huge fresh mural thrombus narrowing the lumen of most proximal portion of right pulmonary artery. Autopsy findings indicate that chronic sustained PH state in this patient was attributable to thrombotic and/or thromboembolic disease, and Takayasu-like vasculitis with thrombus played a role in the final deterioration of respiratory state through exacerbation of PH. In sarcoidosis patients, vasculitic lesions which can be formed in both small and large pulmonary arteries must be raised as the differential diagnosis for the initial cause of PH as well as the accelerating factor of PH.

Sarcoidosis--scientific progress and clinical challenges

Sarcoidosis is an uncommon systemic inflammatory disorder characterized by noncaseating granulomatous inflammation that most commonly affects the lungs, intrathoracic lymph nodes, eyes and skin. One-third or more of patients with sarcoidosis have chronic, unremitting inflammation with progressive organ impairment. Findings of family and genetic studies indicate a genetic susceptibility to sarcoidosis, with genes in the MHC region having a dominant role. Immunologic hallmarks of the disease include highly polarized expression of cytokines produced by type 1 T helper cells and tumor necrosis factor (TNF) at sites of inflammation. Increasing evidence obtained within the past decade suggests the etiology of sarcoidosis predominantly involves microbial triggers, with the most convincing data implicating mycobacterial or propionibacterial organisms. Innate immune mechanisms, possibly involving misfolding and aggregation of serum amyloid A, might have a critical role in the pathobiology of sarcoidosis. Despite these advances, there are no clinically useful biomarkers that can assist the clinician in diagnosis, prognosis or assessment of treatment effects. Corticosteroids remain the cornerstone of therapy when organ function is threatened or progressively impaired. The role of immunosuppressive drugs and anti-TNF agents in the treatment of sarcoidosis remains uncertain, and there are no FDA-approved therapies. Meaningful progress in developing clinically useful tools and new therapies will depend on further advances in understanding the pathogenesis of sarcoidosis and its disease-specific pathways.

Genetic variation in GREM1 is a risk factor for fibrosis in pulmonary sarcoidosis

Sarcoidosis is a granulomatous systemic disorder most often affecting the lung. Pulmonary fibrosis develops in approximately 10%-15% of patients with sarcoidosis. The human gene GREM1 encodes gremlin, a member of the bone morphogenetic protein antagonist family. Bone morphogenetic proteins are essential for the maintenance of tissue homeostasis and regeneration after injury. We examined associations between genetic variation in GREM1 and pulmonary disease outcome in patients with pulmonary sarcoidosis. Four common tag single nucleotide polymorphisms spanning GREM1 were genotyped in 483 controls and in 237 sarcoidosis patients with radiographic data at pulmonary disease outcome, defined by chest X-ray after a minimum of 4 years follow-up. Highly significant differences were found between GREM1 genotype frequencies in sarcoidosis patients without chest X-ray abnormalities (stage 0) (n = 116) versus patients who had fibrosis on chest X-ray (stage IV) (n = 59) at pulmonary disease outcome. The most significant association was with GREM1 rs1919364. The recessive model resulted in an increased risk of fibrosis development for homozygous carriers of the C allele at GREM1 rs1919364 versus carriers of the G allele [P = 9.3 × 10⁻⁷, χ² = 24.1, odds ratio (OR) = 6.37 (2.89-14.1)]. This study is the first to suggest that genetic variation of GREM1 predisposes to pulmonary fibrosis in sarcoidosis patients. Carriers of the GREM1 CC genotype at position rs1919364 were at 6.4 times greater risk for developing fibrosis.

[Novel immunopathological approaches to pulmonary arterial hypertension]

Inflammation is important for the initiation and the maintenance of vascular remodeling in the most commun animal models of pulmonary hypertension (PH), and its therapeutical targeting blocks PH development in these models. In human, pulmonary vascular lesions of PH are also the source of an intense chemokine production, linked to inflammatory cell recruitment. However, arteritis is uncommon in PH patients. Of note, current PH treatments have immunomodulatory properties. In addition, some studies have shown a correlation between levels of circulating inflammatory mediators and patients' survival. The study of autoimmunity in the pathophysiology of pulmonary arterial hypertension is becoming an area of intense investigation. New immunopathological approaches to PH should allow the development of innovative treatments for this very severe condition.

[Pulmonary sarcoidosis imaging]

Sarcoidosis is a juvenile systemic granulomatosis. Its polymorphic clinical presentation depends on its different localisations, thoracic and extrathoracic. The role of imaging is very important for all localisations; but for mediastinopulmonary involvement, which is the most frequent (>90% of cases), it plays a major role in detecting the disease, diagnosing it, its prognosis, decision-making regarding treatment of it and in the monitoring of its development. Standard radiography, which sometimes detects the disease, forms the basis for its four-stage prognostic classification. CT scanning enables the study of mediastinal and hilar lymphadenopathy and the study of parenchyma, making it possible to identify micronodules of lymphatic distributions, alveolar opacities, septal lines, ground-glass hyperintensities, nodules surrounded by a ring of satellite micronodules, peribronchovascular thickening; all potentially reversible lesions. Elsewhere, it highlights irreversible fibrous lesions: hilar peripheral linear opacities; septal linear opacities; bronchial distortion, honeycomb destruction or even perihilar fibrotic masses. Less frequently we can visualise bronchiolar or cystic involvement. Benign in most cases, the sarcoidosis prognosis becomes bleaker in the event of hemoptysis, Aspergillus colonisation or before the onset of pulmonary hypertension.

A concise review of pulmonary sarcoidosis

This is an update on sarcoidosis, focusing on etiology, diagnosis, and treatment. In the area of etiopathogenesis, we now have a better understanding of the immune response that leads to the disease as well as genetic factors that modify both the risk for the disease and its clinical outcome. Several groups have also identified possible agents as a cause for sarcoidosis. Although none of these potential causes has been definitely confirmed, there is increasing evidence to support that one or more infectious agents may cause sarcoidosis, although this organism may no longer be viable in the patient. The diagnosis of sarcoidosis has been significantly aided by new technology. This includes the endobronchial ultrasound, which has been shown to increase the yield of needle aspiration of mediastinal and hilar lymph nodes. The positive emission tomography scan has proven useful for selecting possible biopsy sites by identifying organ involvement not appreciated by routine methodology. It has also helped in assessing cardiac involvement. The biologic agents, such as the anti-tumor necrosis factor antibodies, have changed the approach to refractory sarcoidosis. There is increasing evidence that the clinician can identify which patient is most likely to benefit from such therapy. As new and more potent antiinflammatory agents have been developed, it is clear that there are other factors that burden the patient with sarcoidosis, including fatigue and sarcoidosis-associated pulmonary hypertension. There have been several recent studies demonstrating treatment options for these problems.

Outcome measures of the 6 minute walk test: relationships with physiologic and computed tomography findings in patients with sarcoidosis

Background

We assessed the relationship between physiologic parameters, computed tomography patterns, 6 minute walk distance (6MWD) and the distance-saturation product [DSP; defined as the product of the 6MWD and the lowest oxygen saturation during the 6 minute walk test (6MWT)]. In addition, we investigated factors affecting 6MWD in patients with pulmonary sarcoidosis.

Methods

We performed a retrospective study of patient demographics, treatment, pulmonary function, 6MWT, echocardiography and computed tomography results.

Results

Fifty nine patients were included in this study. Their mean+standard deviation age was 47.5 years + 12.5 years, and 42 (71.2%) were female. Mean pulmonary function parameters for forced vital capacity (FVC), forced expiratory volume in 1 second (FEV₁) and total lung capacity (TLC) results, as percentages of predicted values, were 77.6 ± 22.2, 77.1 ± 22.8 and 78.7 ± 16.1, respectively. Comparison of the DSP with distance walked revealed a significant correlation with factors underlying reduced 6MWD, including gender, pulmonary function indices, partial pressure of oxygen (PaO₂), and Borg dyspnea score. Other factors were significantly associated with DSP but not distance; these included lung fibrosis (p = 0.02), pulmonary hypertension (p = 0.01) and systemic therapy (p = 0.04). Backward elimination stepwise multiple regression analysis revealed that gender, and FEV₁ were independent predictors of 6MWD, but FEV₁ was more strongly related when DSP applied [DSP, R² = 0.53, p = 0.02; distance, R² = 0.45, p < 0.0001].

Conclusion

Our findings reveal that, compared to 6MWD alone, the DSP is correlated with a greater number of factors associated with reduced 6MWT performance. Therefore, the DSP may be a useful indicator of functional status in patients with sarcoidosis. Additional large-scale studies are warranted to validate our findings.

Sarcoidosis and its otolaryngological implications

Sarcoidosis and its aetiopathogenesis, epidemiology and diagnostic procedures (including the Kveim reaction) are presented in this paper. The clinical manifestations of this disease, especially in otolaryngological organs, including the larynx, salivary glands, nose and paranasal sinuses, are described. Treatment procedures, including surgical interventions and prognosis, are also discussed.

Pulmonary sarcoidosis: the 'Great Pretender'

Sarcoidosis has a wide spectrum of appearances within the thorax. This review will discuss and illustrate the range of pulmonary manifestations on high-resolution computed tomography and chest radiography, concentrating on atypical features and examples of sarcoidosis mimicking other lung diseases. All included cases have been histologically confirmed. Such variable imaging appearances should alert the radiologist to consider sarcoidosis as a differential diagnosis in the context of interstitial lung disease.

Detection of pulmonary hypertension with multidetector CT and echocardiography alone and in combination

PURPOSE

To test the reliability of potentially new computed tomographic (CT) indicators of pulmonary hypertension (PH) and to establish whether a combination of CT and echocardiographic measurements was more predictive of PH than either test alone.

MATERIALS AND METHODS

The institutional review board approved this retrospective study; patient consent was not required. Seventy-seven patients undergoing right-sided heart catheterization were examined. CT diameters of the main pulmonary artery, ascending aorta, and thoracic vertebra and cross-sectional area of the main pulmonary artery were measured. Segmental and subsegmental arterial diameters were recorded, and segmental artery size was compared with adjacent bronchus size by using a semiquantitative scoring system. The relationship between CT measurements and mean pulmonary arterial pressure (mPAP) was tested with linear regression. Multivariate regression was used to establish a composite index of mPAP by using CT markers of PH with echocardiography-derived right ventricular systolic pressure (RVSP). Post hoc logistic regression and receiver operating characteristic curve analysis were performed to test the diagnostic ability of the CT-echocardiography composite.

RESULTS

The ratios of the diameter of the main pulmonary artery to the diameter of the ascending aorta (R(2) = 0.45; P < .001) and of the cross-sectional area of the pulmonary artery to the diameter of the ascending aorta (R(2) = 0.45; P < .001) correlated equally with mPAP. The ratio of the diameter of the main pulmonary artery to the diameter of the thoracic vertebra, the segmental arterial diameter, and the segmental artery-to-bronchus ratio were related to mPAP but did not strengthen correlations compared with the ratio of the diameter of the main pulmonary artery to the diameter of the ascending aorta alone. A composite index of the ratio of the diameter of the main pulmonary artery to the diameter of the ascending aorta and echocardiography-derived RVSP was more strongly related (R(2) = 0.55) to mPAP and was more significantly predictive of PH than either measure alone.

CONCLUSION

A combination of CT and echocardiographic markers of PH is more closely related to mPAP than either test in isolation.

Sarcoidosis-induced pericarditis in a patient with portopulmonary hypertension: a case report

Portopulmonary hypertension is a rare and severe complication of patients with cirrhosis. Sarcoidosis, a disease of unknown etiology, is also a cause of pulonary hypertension and right heart dysfunction. We report the case of a 51-year-old male patient, suffering from cirrhosis due to Wilson's disease, portal hypertension and pulmonary hypertension (PH), who developed severe pericarditis. Wilson's disease was diagnosed 8 years before his last admission to our hospital and was being successfully treated with D-penicillamine. PH was recognized 2 years before admission and being treated with bosentan. The patient complained for dyspnea at rest and the 2D echocardiogram revealed a significant amount of pericardial fluid. All other causes of acute pericarditis were excluded and his laboratory, imaging and histopathological investigation showed evidence of sarcoidosis. He underwent a therapy with corticosteroids (methylprednisolone) and his follow-up examination showed remarkable decrease of the levels of mean pulmonary artery pressure and pericardial fluid.

Sarcoidosis-associated pulmonary hypertension: a role for endothelin receptor antagonists?

Data on the treatment of sarcoidosis-associated pulmonary hypertension are scarce, while the variety of underlying pathophysiologic mechanisms are a major limitation in the implementation of a universal therapy. We report a 47-year-old male patient who presented with stage II sarcoidosis and associated severe pulmonary hypertension. Corticosteroid treatment resolved parenchymal lesions of the lung while vascular involvement did not respond, with the patient remaining in poor functional status. Addition of bosentan, a dual endothelin receptor antagonist, resulted in marked improvement in functional class and exercise capacity of the patient, allowing gradual tapering of steroids.

Updated clinical classification of pulmonary hypertension

The aim of a clinical classification of pulmonary hypertension (PH) is to group together different manifestations of disease sharing similarities in pathophysiologic mechanisms, clinical presentation, and therapeutic approaches. In 2003, during the 3rd World Symposium on Pulmonary Hypertension, the clinical classification of PH initially adopted in 1998 during the 2nd World Symposium was slightly modified. During the 4th World Symposium held in 2008, it was decided to maintain the general architecture and philosophy of the previous clinical classifications. The modifications adopted during this meeting principally concern Group 1, pulmonary arterial hypertension (PAH). This subgroup includes patients with PAH with a family history or patients with idiopathic PAH with germline mutations (e.g., bone morphogenetic protein receptor-2, activin receptor-like kinase type 1, and endoglin). In the new classification, schistosomiasis and chronic hemolytic anemia appear as separate entities in the subgroup of PAH associated with identified diseases. Finally, it was decided to place pulmonary veno-occlusive disease and pulmonary capillary hemangiomatosis in a separate group, distinct from but very close to Group 1 (now called Group 1'). Thus, Group 1 of PAH is now more homogeneous.

[Interstitial lung diseases and pulmonary hypertension]

The prevalence of pulmonary hypertension in interstitial lung disease (ILD) is high (30-40%). However, diagnosis of pulmonary hypertension in ILD is often delayed. Pulmonary hypertension can occur in the absence of advanced pulmonary dysfunction or severe hypoxia and is associated with a worse prognosis. A number of pathogenic mechanisms such as oxidative stress, cytokines, and the endothelin system have been implicated in remodeling of both the lung parenchyma and the vessels. In addition, hypoxic vasoconstriction, vascular destruction and progressive fibrosis play an important role. Since clinical signs are often non-specific echocardiography, radiology and laboratory parameters such as NT-proBNP may be helpful. However, the definitive diagnosis of pulmonary hypertension is still confirmed by right heart catheterization. Treatment options of pulmonary hypertension in ILD are limited to the treatment of the underlying diseases. Newer vasodilating drugs may improve the prognosis but have first to be evaluated in clinical trials. Lung or lung and heart transplantation is the therapeutic option in end stage disease.

Comorbidities of advanced lung disease

Lung disease in advanced stages is often accompanied by multiple comorbidities. Often, these processes lead to significant morbidity and occasionally mortality. Symptoms of pulmonary comorbidities, including pulmonary embolus, pulmonary hypertension, sleep-disordered breathing, and lung malignancy, may be intertwined with symptoms of advancing lung disease. However, the occurrence of extrapulmonary processes, including depression, diabetes mellitus, osteoporosis, and gastroesophageal reflux disease, may be subtle. Clinicians caring for advanced lung disease should be aware of the many comorbid processes that may accompany advancing lung disease.

The Histology of Pulmonary Sarcoidosis: A Review with Particular Emphasis on Unusual and Underrecognized Features

The pathologist is frequently involved in the diagnostic approach to the patient with suspected sarcoidosis. Although the histologic diagnosis is generally not difficult, atypical and underrecognized features may occasionally occur and may result in diagnostic problems. The authors review the histology of pulmonary sarcoidosis, focusing particularly on these unusual problematic findings.

Clinical outcomes in sarcoidosis after cessation of infliximab treatment

BACKGROUND AND OBJECTIVE

Infliximab appears to be efficacious for the treatment of recalcitrant forms of sarcoidosis. However, there are minimal data concerning the course of sarcoidosis once infliximab is discontinued.

METHODS

Clinical outcomes in patients who had received infliximab and had discontinued it for at least 2 months were analysed retrospectively. The severity of involvement of the index organ from the time of discontinuation of infliximab was compared with that at the end of the follow-up period.

RESULTS

Fourteen patients with sarcoidosis who had been treated with infliximab and had discontinued this therapy were identified. Before discontinuation of infliximab, 9 of the 14 patients (64%) responded to infliximab treatment and only one (7%) deteriorated. Patients who discontinued infliximab were followed for a mean of 12 months. At the end of the follow-up period, 12 of the 14 patients (86%) had deteriorated as compared with their status at the time of discontinuation of infliximab and two (14%) had remained stable. Kaplan-Meier analysis of time to clinical deterioration showed that half the patients deteriorated within 3 months of discontinuing infliximab. Patients who had discontinued infliximab appeared to be more likely to have their dose of prednisone increased.

CONCLUSION

Patients with recalcitrant sarcoidosis who receive infliximab appear likely to deteriorate after discontinuation of this medication.

Treatment of sarcoidosis-associated pulmonary hypertension. A two-center experience

BACKGROUND

Pulmonary hypertension (PH) is a common complication of sarcoidosis that is associated with increased mortality. The pathogenesis of PH in sarcoidosis is uncertain, and the role of pulmonary arterial hypertension (PAH)-specific therapies remains to be determined.

METHODS

We conducted a retrospective study of patients with sarcoidosis and PH at two referral centers. New York Heart Association (NYHA) functional class, exercise capacity, hemodynamic data, pulmonary function tests, and survival were collected and analyzed.

RESULTS

Twenty-two sarcoidosis patients treated with PAH-specific therapies were identified. After a median of 11 months of follow-up, NYHA class was improved in nine subjects. Mean 6-min walk distance (n = 18) increased by 59 m (p = 0.032). Patients with a higher FVC experienced a greater increment in exercise capacity. Among 12 patients with follow-up hemodynamic data, mean pulmonary artery pressure was reduced from 48.5 +/- 4.3 to 39.4 +/- 2.8 mm Hg (p = 0.008). The 1- and 3-year transplant-free survival rates were 90% and 74%, respectively.

CONCLUSIONS

PAH-specific therapy may improve functional class, exercise capacity, and hemodynamics in PH associated with sarcoidosis. Prospective, controlled trials of PAH therapies for sarcoidosis are warranted to verify this apparent benefit. Mortality among the study population was high, highlighting the need for urgent evaluation at a lung transplant center.

Pulmonary hypertension in interstitial lung disease

Pulmonary hypertension (PH) may complicate the course of many forms of advanced interstitial lung disease (ILD) and has been shown to portend a worse outcome. The aetiology of PH is likely multifactorial with variable contribution of factors amongst the different diseases. The most common such conditions include idiopathic pulmonary fibrosis, sarcoidosis, connective tissue disease-related ILD and pulmonary langerhans cell histiocytosis. Whether the course and impact of PH in these conditions can be modified by therapy requires further study.

Up-to-date in pulmonary and extrapulmonary sarcoidosis

Sarcoidosis is a multisystemic immune disorder of unknown cause characterized by the formation of epithelioid granuloma in involved organs particularly the lung and the lymphatic system. Consistent recent advances have been made on the clinical, therapeutical and pathogenetic aspects.

CLINICAL ASPECTS

Various clinical phenotypes are better characterized and efforts to grade the severity could facilitate genetic studies and therapeutic trials. Pulmonary hypertension and some infrequent or atypical pulmonary manifestations as well as some rare extrapulmonary localizations have been thoroughly studied. Sarcoidosis-like granulomatosis due to identified causes constitute interesting models and have to be differentiated from sarcoidosis. THERAPEUTICAL ASPECTS: Anti-TNFalpha drugs have been investigated and infliximab has been proved efficient even though some limits to its efficiency have to be taken into account. PATHOGENETIC ASPECTS: Finally, advances concerning the pathogenesis, particularly genetic predisposing factors and phenotype/genotype correlations have been made.

Pulmonary hypertension in interstitial lung disease

PURPOSE OF REVIEW

To examine recent advances in the understanding of the prevalence, pathophysiology, natural history, diagnosis, and treatment of pulmonary hypertension associated with interstitial lung disease.

RECENT FINDINGS

Significant progress has recently been made in understanding the etiology of various causes of pulmonary hypertension, including those associated with interstitial lung disease, and new data regarding the various pathophysiologic mechanisms of pulmonary hypertension in interstitial lung disease have been published. Therapeutic agents that were initially studied in patients with idiopathic pulmonary arterial hypertension are now being applied to interstitial lung disease-related pulmonary hypertension. Short-term hemodynamic benefits and disease-related quality of life outcomes that are associated with these advanced therapies are now better understood, but data regarding long-term outcomes and the efficacy of combination therapies remain lacking for interstitial lung disease-related pulmonary hypertension. Lung transplantation outcomes in the treatment of pulmonary hypertension associated with interstitial lung disease have been further defined.

SUMMARY

Pulmonary hypertension associated with interstitial lung disease is now frequently recognized and is associated with substantial morbidity and mortality. Various new pharmacotherapies as well as lung transplantation are increasing the treatment options for these disorders, although timing of advanced therapies and long-term benefits and toxicities remain uncertain.

Diagnosis of sarcoidosis

PURPOSE OF REVIEW

To describe the recent advances in the diagnostic procedures for sarcoidosis and explore future directions.

RECENT FINDINGS

Novel imaging techniques have been explored in sarcoidosis, such as positron emission tomography using L-[3-F]-alpha-methyltyrosine, which is more specific for malignancy than F-fluorodeoxyglucose positron emission tomography. The combined modality of L-[3-F]-alpha-methyltyrosine-positron emission tomography with fluorodeoxyglucose-positron emission tomography could successfully discriminate sarcoidosis from malignancy. The finding of delayed enhancement in cardiac magnetic resonance imaging could identify cardiac involvement of sarcoidosis with higher sensitivity than echocardiography, thallium scintigraphy, and gallium scintigraphy. Endobronchial ultrasonograpy-guided transbronchial needle aspiration is a safe and useful tool for diagnosing sarcoidosis with a diagnostic accuracy, sensitivity and specificity of 85-93, 78-89, and 92-96%, respectively. Developments in genetics have demonstrated that 99% of the human leukocyte antigen DRB1*0301/DQB1*0201-positive patients with Löfgren's syndrome show a spontaneous remission, in contrast to only 55% of the human leukocyte antigen DRB1*0301/DQB1*0201-negative patients. These alleles could be novel promising factors for discriminating a prognosis in Löfgren's syndrome.

SUMMARY

Recent development including novel imaging techniques, novel biopsy procedures, and genetic analyses could be of value for the diagnosis of sarcoidosis.

Outcome of sarcoidosis

Sarcoidosis is a chronic granulomatous inflammatory disease of unknown etiology with heterogeneous outcome. Based on the natural history or clinical treatment course, the outcomes of cases can be divided into two wings: spontaneous regression (self-limited disease) or progression of extensive fibrotic lesions as a postgranulomatous fibrosis. In addition to examining these outcomes, this article focuses on several related concepts, including chronicity (persistence of the lesions), relapse/recurrence, deterioration, and mortality. It also reviews the outcomes from the point of view of relevant clinical phenotypes, the natural disease course, the effects of treatment, and the effects of lung transplantation. Finally, it considers the effects of pulmonary hypertension, various genetic factors on the outcomes, and the efficacy of several novel therapeutic drugs in treating sarcoidosis.

Pulmonary hypertension caused by sarcoidosis

Pulmonary hypertension is an uncommon complication of sarcoidosis, but in severe pulmonary disease it occurs frequently. It is an important cause of cryptogenic dyspnea in sarcoidosis patients and can occur despite the absence of pulmonary fibrosis. The true prevalence is unknown. With the advent of specific therapies for pulmonary hypertension, there has been a resurgence of interest in the pathophysiology, diagnosis, and treatment of sarcoidosis-associated pulmonary hypertension. This article reviews the status of the current epidemiologic, pathophysiologic, and therapeutic knowledge regarding this entity.

Pulmonary hypertension associated with lung transplantation obliterative bronchiolitis and vascular remodeling of the allograft

Pathologic obliterative bronchiolitis (OB)/Bronchiolitis obliterans syndrome (pathologic OB/BOS) is the major obstacle to long-term survival post-lung transplantation (LT). Our group has demonstrated that pulmonary hypertension (PH) complicates the course of chronic inflammatory lung diseases that have similarities to pathologic OB/BOS and that vascular remodeling of the bronchial circulation occurs during BOS. Consequently, we hypothesized that PH is associated with pathologic OB/BOS and may result from a vasculopathy of the allograft pulmonary circulation. We conducted a single-center, retrospective study and examined the presence of PH and vasculopathy in patients with pathologic OB/BOS. Fifty-two pathologic specimens post-LT were recovered from January 10, 1997 to January 5, 2007 and divided into two groups, those with and without pathologic OB/BOS.PH was defined as a mean pulmonary artery pressure (mPAP) > 25 mmHg by right heart catheterization (RHC) or right ventricular systolic pressure (RVSP) > or = 45 mmHg by transthoracic echocardiogram (TTE). PH was more prevalent in those LT recipients with pathologic OB/BOS (72% vs. 0%, p = 0.003). Furthermore, pulmonary arteriopathy and venopathy were more prevalent in patients with pathologic OB/BOS (84% vs. 4%, p < 0.0001, and 77% vs. 35%, p = 0.004, respectively). PH is common in LT recipients with pathologic OB/BOS and is associated with a vasculopathy of the allograft pulmonary circulation.

Vaso-active therapy can improve 6-min walk distance in patients with pulmonary hypertension and fibrotic interstitial lung disease

BACKGROUND

Dyspnea and functional limitation in interstitial lung diseases (ILD) are not always adequately explained by the degree of compromise in pulmonary function alone. Pulmonary hypertension (PH) is felt to be a major contributor to morbidity and mortality in these patients. It is not clear whether treatment with newer vaso-active agents benefits patients with PH in the setting of moderate or severe ILD.

METHODS

Medical records of patients followed at our institution between July 2001 and June 2005 were reviewed to identify patients with moderate or severe fibrotic ILD and PH. Data regarding demographics, hemodynamics, and clinical characteristics at baseline and during follow-up were collected.

RESULTS

We identified 19 patients who met our inclusion criteria and in whom vaso-active therapy [epoprostenol (N=10), bosentan (N=9)] was initiated. Most patients [(15/19(79%)] showed an initial positive response to therapy and improved their 6-min walk distance (6MWD) by >50m (responders) and 12/15 (80%) improved by at least 1 WHO functional class. At 1-year follow-up, 7 of 15 (47%) 'responders' had deteriorated significantly. None of the patients died during 1 year of follow-up.

CONCLUSIONS

Epoprostenol and bosentan produced short-term functional benefit in our patients with PH and moderate or severe restrictive ILD. The generalizability of these results awaits the results of larger, prospective, randomized trials in such patients.

[Pulmonary vein stenosis after radiofrequency ablation for atrial fibrillation]

INTRODUCTION

Pulmonary vein stenosis is a rare condition with a high mortality. With the advent of radiofrequency ablation for atrial fibrillation a new cause of pulmonary vein stenosis has emerged.

OBSERVATIONS

We report two cases of severe pulmonary vein stenosis. In the first case the diagnosis was obtained rapidly and balloon angioplasty with stent implantation was performed in the two left pulmonary veins. Recurrent occlusion occurred within the stents, extensive pulmonary infiltrates resembling pulmonary venous infarction developed and the patient died. In the second case the diagnosis was missed initially because the clinical picture suggested thrombo-embolic disease or infection. Balloon angioplasty with stent implantation was performed later. Restenosis occurred after 18 months. These two cases illustrate the frequency with which percutaneously inserted venous prostheses thombose.

CONCLUSIONS

Clinicians should be familiar with the possibility of the development of pulmonary vein stenosis after radiofrequency ablation for atrial fibrillation. Pulmonary vein stenosis remains a difficult condition to manage. The pulmonary infarction should probably be considered as an urgent indication for surgical resection or even transplantation.