Advances in Pulmonary Hypertension

Myung H. Park, MD

Pulmonary hypertension (PH) associated with left heart disease is the single most common form of PH we encounter in clinical practice today. Divided into 3 categories – systolic dysfunction, diastolic dysfunction, valvular disease – the presence of PH is well recognized to portend worse outcome across the spectrum of cardiac disorders. PH associated with diastolic dysfunction presents unique challenges for clinicians, as at first glance it shares many similar features with pulmonary arterial hypertension (PAH). Furthermore, the incidence of PH with diastolic dysfunction is in sharp rise, in parallel with the aging population and increase in incidence of obesity. It is no wonder that I often hear my referring colleagues comment, “All of my patients have PH. It has become an epidemic!”

Thus, it has been a distinct pleasure to have the opportunity to bring together a leading group of expert clinicians in this rapidly evolving field to address specifically some of the most frequently asked questions in the areas of presentation, diagnosis, and treatment of PH associated with diastolic dysfunction (aka diastolic heart failure, pulmonary venous hypertension, and heart failure with preserved ejection fraction [HFpEF]). Dr Soto, representing the pulmonary group who are often asked to evaluate these patients for dyspnea of unclear etiology, gives a well-thought-out strategy to formulate pretest probability of HFpEF versus PAH by integrating the relevant clinical risk factors. How best to utilize echocardiography to differentiate between PAH and HFpEF is eloquently addressed by Drs Raina and Forfia in their detailed explanation of key findings that readily separate the two entities. They also give a step-wise, integrative approach to prioritize echo features to further add to the pretest probability of distinguishing diastolic dysfunction versus PAH – and why the pulmonary artery systolic pressure number may be the least important of all the findings that echocardiogram provides.

Right heart catheterization remains the ultimate arbiter and, like any tool, it is critical for the operator to know how to maneuver and interpret the information correctly. Dr Mathier provides the key do's and don'ts of performing right heart catheterization and how to avoid the pitfalls in interpreting the data. Furthermore, he explores the often asked question “What is PH ‘out of proportion’?” Finally, Dr Champion walks us through the therapeutic realm for PH associated with left heart disease, most notably those therapies that have been studied and found to be ineffective. The promising aspects of phosphodiesterase-5 inhibitors are discussed with the need for randomized clinical trials to determine its potential usefulness in this population. The Roundtable discussion engages Drs Alvarez, De Marco, Robbins, and Semigran, who share their views on how HFpEF impacts their clinical practice and how they approach this entity.

Though we may not have a clear picture yet, we are making strides in improving our understanding and coming to appreciate PH associated with diastolic dysfunction. I believe this issue will prove to be a useful resource in managing this increasing group of PH patients.

Finally, I would like to thank Erika Berman Rosenzweig for her encouragement and guidance in completing this issue.