Advances in Pulmonary Hypertension

Guest Editor's Memo

Translating Evidence into Clinical Practice

Pulmonary hypertension (PH) associated with lung disease and hypoxia (WHO Group III) is one of the most common forms of pulmonary hypertension. It also encompasses a very diverse group of diseases where the PH is an extremely important determinant of functional limitation and prognosis. In this group of diseases, PH is common in advanced disease, however its prevalence in milder disease is not known. None of the non-invasive screening methods have been found to be accurate and the best screening tool, Doppler echocardiography, is especially prone to error. Treating these patients can be a frustrating experience because of the lack of prospective trials and the associated underlying lung disease. Several questions remain unanswered including the populations to be screened, best diagnostic approach, and treatment options. In the current issue of Advances, all these questions have been addressed by some of the key thought-leaders in this field.

In our article on PH in Obstructive Sleep Apnea (OSA), Dr Chua and I have tried
to summarize the clinically relevant literature on pulmonary hemodynamics in patients with OSA. We point out that PH in OSA is a multi-factorial process and may have important implications in terms of functional capacity and prognosis in these
patients. CPAP therapy may be helpful in patients with mild PH, however more studies are needed to better define the role of PH-specific therapy in patients with more significant PH.
The articles by Dr Klinger on PH in interstitial lung diseases, Dr Girgis on PH in sarcoidosis, and Dr Preston on PH in COPD all provide an exhaustive yet focused
review of the literature. These authors make several recommendations that readers can utilize in their clinical practice in terms of diagnostic evaluation and when faced with various treatment dilemmas.

The roundtable is hosted by me and discussants are Drs Nicholas Hill and Steve Nathan, who bring a wealth of experience and wisdom to the discussion. During the roundtable discussion, we addressed several clinically relevant questions that many of us are faced with everyday including the elusive questions on "disproportionate PH" and the art of choosing who to treat and with what.

I have really enjoyed planning this issue with the expert
review of Dr Charles Burger and hope that all of you will come away with important information that will prove useful in caring for your patients.

Omar A. Minai, MD
Guest Editor

Editor's Memo

It is with great excitement that I introduce the Fall 2009 issue of Advances, devoted to pulmonary hypertension in the setting of lung or respiratory disease (or WHO Diagnostic Group III). Dr Omar Minai has done an outstanding job of coordinating the issue and contri-buting one of the articles.

The topic of pulmonary hypertension in patients with underlying pulmonary disorders is critical. What are the mechanisms involved in the development of PH in these patients? How common is PH in this group? How severe? When can we attribute PH in an individual patient to the underlying pulmonary disease and when is the PH "out of proportion"? And importantly, can we treat any of these patients with PAH-specific therapies?

This last question is, indeed, a charged topic. In reality, PAH-specific drugs are already being used in patients with underlying pulmonary disease. Does this represent inappropriate, off-label use of costly therapies, or thoughtful, albeit empiric, appli-cation of targeted treatment to patients who may share many of the histopathologic features with more "typical" PAH patients? The truth, of course, is probably somewhere in the middle, but what are the data?

As someone who lectures widely on all aspects of pulmonary hypertension, I am asked after virtually every talk whether the current PAH therapies are ever indicated in patients with PH and underlying lung or respiratory disease, especially COPD. This is not a surprising question. After all, these are the patients that physicians see. A community-based pulmonologist rarely ever sees a 30-year-old woman with idiopathic pulmonary arterial hypertension. What he or she sees regularly is a 65-year-old overweight patient with some underlying sleep apnea, hypertension, and COPD. Some of these patients develop pulmonary hypertension, sometimes with severe right ventricular failure.

The practitioners want to know from us, the experts, what to do to help these patients. We need to provide a framework by which clinicians can approach and evaluate such a patient when he or she develops PH. I am hopeful that this issue of Advances will provide, to the practicing physician, at least parts of that framework.

Richard N. Channick, MD
Editor-in-Chief