Although the weather at the recent 2018 CHEST annual meeting held in San Antonio, Texas was unexpectedly rainy, it did nothing to dampen the enthusiasm for discussing pulmonary vascular disease. Although patient selection and treatment options are typically highly controversial topics, the 2018 CHEST meeting delivered sessions that were both intellectually stimulating and highly entertaining.
Treatment with pulmonary vasodilator medication is traditionally reserved for patients with Pulmonary Arterial Hypertension (PAH), a diagnosis which requires invasive hemodynamic testing and exclusion of underlying disease of the left heart or lungs themselves. Treatment options typically fall into three distinct vasodilatory pathways, however the only medication shown to decrease mortality (epoprostenol, which acts upon the prostacyclin pathway) requires parenteral therapy. The decision on which treatment modality to start, when to add treatment from another pathway, and when to escalate to parenteral therapy is often an area of considerable debate, and this meeting was no exception. Medication therapy has taken on a new importance following the discovery that up-front combination therapy is superior to sequential monotherapy, and discussions were lively. Exciting research on the risks, benefits, and strategies for transitioning from parenteral therapy to some of the newest treatment options, oral medications that act upon the prostacyclin pathway, was highlighted. The process of choosing one of three oral medications that act upon the nitric oxide pathway was also detailed, and promising new inhalational modes of delivery of prostacyclin pathway medications was touched upon.
Although the decision of which targeted vasodilator therapy in PAH is difficult enough, the risks and benefits of using this therapy in non-PAH patients with comorbid heart or lung disease is even more controversial. The consensus reached by experts in the field was that, although not recommended in the guidelines, a trial of targeted therapy can be considered in carefully selected patients with attention paid to the risks and benefits and close monitoring for adverse effects. Although the relevant research studies were comprehensively highlighted during the packed (but lively) session, by the end it was clear that this debate was far from over.
Exciting discussions were not limited to pulmonary physicians, a number of experts in cardiovascular diseases were also present to offer their insights on the management of pulmonary vascular disease in the setting of valvular heart disease. Pulmonary hypertension complicating valvular heart disease is associated with elevated morbidity and mortality during valve correction procedures, and the need for a multidisciplinary approach to these challenging patients was not lost on those in attendance. Additionally, the cardiologists’ perspective offered a refreshing look at pulmonary vascular disease from the “other” side of the heart.
Thromboembolic disease, specifically “sub-massive” pulmonary embolism, was also discussed in great detail. With the advent of new, catheter-based modalities for delivering lower doses of thrombolytic agents directly to the pulmonary vasculature, as well as pulmonary embolism response teams, a seismic shift towards employment of catheter-based therapy in the treatment of these types of thromboembolic events has recently taken place. However, as was highlighted in the excellent sessions, the evidence for these newer therapeutic options has not yet caught up with the embrace of these technologies. Although the jury is still out on the optimal modality of treatment or the role that catheter-based therapy plays in the management of intermediate-high risk pulmonary embolism, it is clear that this issue will continue to grow in importance in the years ahead.
Although a number of controversial topics in pulmonary hypertension were discussed at this year’s CHEST annual meeting, a clear theme was present throughout: the importance of research in highlighting and clarifying areas of clinical uncertainty. With the results of the recent 2018 World Symposium in Pulmonary Hypertension eagerly anticipated and likely to result in a paradigm shift on how pulmonary hypertension is diagnosed and treated, the need for avenues to disseminate high-quality research has never been greater. Thankfully the educational content of the annual meeting is superb, distilling the year’s scientific advancement into spirited debates and engaging sessions. I’m not sure if next year’s conference will clarify some of the controversies in pulmonary vascular disease discussed this year, but I know my fellow pulmonologists and pulmonary vascular disease specialists will find the trip to New Orleans both educationally worthwhile and highly entertaining.
Arun Jose, MD is a Clinical Instructor in the Department of Pulmonary/CCM at the University of Cincinnati, with a clinical and research interest in pulmonary vascular disease.