Volume 20: Issue 2

There is overlap between pulmonary hypertension and metabolic disorders. According to the 6th World Symposium on Pulmonary Hypertension, glycogen storage diseases and Gaucher disease are included in the heterogeneous group 5 pulmonary hypertension. This review highlights the known insights into the role of metabolic disorders and pulmonary hypertension, including epidemiology, pathogenesis, diagnosis, and treatment of pulmonary hypertension. Thyroid disorders have multiple mechanisms by which association with pulmonary hypertension have been described, and these will also be discussed. Pulmonary hypertension-specific targeted therapies and disease-specific therapies have been suggested, and the use alone or in combination has variable responses.

Pulmonary hypertension (PH) has historically been categorized into 5 groups based on similar pathophysiological mechanisms, hemodynamic characteristics, and therapeutic management. Group 5 has evolved over time in concert with our understanding of PH. Currently, it is comprised of diseases leading to PH with unclear and/or multifactorial mechanisms. We will review the historical context of the classification system and how group 5 has morphed into its current classification. We will briefly review the diseases encompassed in group 5 and the current understanding of the associated pathophysiological mechanism leading to PH. We provide a brief review of the diseases of group 5 PH, including the proposed mechanism for PH and potential therapies. Group 5 is comprised of a varied group of diseases, and the mechanisms leading to PH in this group are complex, multifactorial, and often incompletely understood.

Background:

Sickle cell disease (SCD) is characterized by repeated episodes of hemolysis and vaso-occlusion. Hemolysis is a risk factor for the development of pulmonary hypertension (PH), and currently SCD-related PH is classified as World Health Organization group 5 PH. Patients with SCD-related PH have unique hemodynamics, comorbidities, and phenotypes that may contribute to the development of PH.

Implications for Clinicians:

SCD-related PH is defined as a mean pulmonary artery pressure >20 mm Hg, a pulmonary artery occlusion pressure ≤15 mm Hg and relatively low pulmonary vascular resistance (PVR) ( >160 dynes·sec/cm⁵ rather than the typical definition of ≥240 dynes·sec/cm⁵), an important distinction because of a baseline high-cardiac output state in the setting of chronic anemia and low vascular resistance. Diastolic dysfunction is common, and right heart catheterization is warranted to determine if combined precapillary and postcapillary PH is present. Thromboembolism is common among patients with SCD, and screening for chronic thromboembolic pulmonary hypertension is essential. There are few studies evaluating advanced therapies in this population. The mainstay of treatment includes targeting correction of their primary hemoglobinopathy as well as aggressive management of underlying comorbid conditions.

Conclusions:

SCD-related PH is common among patients with SCD and is associated with increased mortality. A high index of suspicion is warranted during evaluation to identify all potential factors that may be contributing to disease.

Dr Oksana Shlobin: Welcome to the roundtable on sarcoidosis-associated pulmonary hypertension (SAPH), moderated by myself and Dr Anjali Vaidya, Co-Director of the Pulmonary Hypertension, Right Heart Failure, and CTEPH Program at Temple University Lewis Katz School of Medicine. Our discussants are Dr Roxana Sulica, Associate Professor of Medicine and Director of the Pulmonary Hypertension Program at NYU Langone, Dr Bob Baughman, Professor of Medicine at University of Cincinnati, and Dr Stacy Mandras, Medical Director of Pulmonary Hypertension Program at AdventHealth.

Dr Anjali Vaidya: Sarcoidosis is probably one of the biggest topics within WHO group 5 PH. There are

BACKGROUND

Sarcoidosis-associated pulmonary hypertension (SAPH) is classified in World Health Organization group 5 pulmonary hypertension (PH) due to the various potential mechanisms of disease pathogenesis including pulmonary arterial hypertension (PAH), left heart disease, fibrotic lung disease, pulmonary vascular stenosis, compressive adenopathy, and fibrosing mediastinitis.^1,2 Although patients with sarcoidosis-associated advanced fibrotic lung disease are at the highest risk and comprise a majority of SAPH patients,^3,4 pulmonary sarcoidosis involving the pulmonary veins presents a unique management challenge and mortality risk. We present a patient with SAPH due to pulmonary vein compression from adenopathy who

Full Issue PDF

Memos

Editor’s Memo

Metabolic Disorders of Pulmonary Hypertension

The Story of Group 5 Pulmonary Hypertension

The Myriad Presentations of Sickle Cell Disease-Related Pulmonary Hypertension

Background:

Implications for Clinicians:

Conclusions:

PH Roundtable: Sarcoidosis and Pulmonary Hypertension

PH Grand Rounds: An Interesting Case of Sarcoidosis-Associated Pulmonary Hypertension

BACKGROUND

Conference Abstracts

Guest Editor’s Memo

A Roundtable Discussion Addressing Patient-Centered Care and Quality of Life in Patients With Pulmonary Arterial Hypertension

Editor’s Memo

Pulmonary Hypertension Associated With Parenchymal Lung Disease