Parth Rali

Pulmonary embolism is one of the leading causes of preventable deaths among hospitalized patients. Advances in diagnostic and therapeutic techniques have expanded the number of potential therapies, and researchers are continuing to expand the evidence base and learn how to use these treatments. As a result, treatment decision-making has become more complex. 

The optimum approach to managing PE now involves a multidisciplinary approach, with input from physicians in pulmonary and critical care medicine, interventional cardiology, interventional radiology, vascular medicine and surgery, hematology, emergency medicine, and cardiac surgery. The paradigm shift has led to increased attention to this life-threatening complication as well as to some controversies in management.  

These controversies are brought to light in today’s scientific symposium on managing acute pulmonary embolism, chaired by Parth Rali, MD; Victor Tapson, MD; and Richard Channick, MD. The debates in the symposium address lack of agreement in the approach to PE, including treatments recommended in guidelines developed by societies such as the American Heart Association, the European Society of Cardiology, and the American College of Chest Physicians. 

“Even before we get involved in management, the guidelines differ somewhat in how PE is classified,” said Dr. Rali, assistant professor of thoracic medicine and surgery at Temple University in Philadelphia.

Another issue is that different specialties tend to follow specific guidelines. “Cardiologists follow the AHA and ESC guidelines, and pulmonologists follow the ACCP guidelines. This itself is enough to create confusion and lead to practice variation and procedural bias among clinicians,” said Dr. Rali.  

Victor Tapson

The treatment options for PE are based on risk categories of low, intermediate (submassive), and high (massive). But patient selection is also a key consideration. For example, aggressive treatment is needed for patients with massive PE, but recognizing the patient’s bleeding risk is crucial because of the significantly higher risk of major bleeding associated with systemic thrombolytic therapy.  

Richard Channick

“Even these risk categories are heterogeneous,” said Dr. Tapson of Cedars-Sinai Medical Center in West Hollywood, California. “A patient with high-risk PE may be receiving high-dose pressor therapy, for example, and still have inadequate hemodynamics, or a patient may be more mildly hypotensive and perhaps need a different approach. Intermediate-risk PE is an even broader category.”

“These treatment decisions and dilemmas are exactly why we established multidisciplinary pulmonary embolism response teams, or PERTs,” added Dr. Channick of UCLA Medical Center in Los Angeles.

“It’s a Catch-22,” said Dr. Rali. “For every patient, you must consider the advantages and disadvantages for every modality of treatment. It’s also why the PERT approach is of such great value.”  

Dr. Rali also noted that as the multidisciplinary approach to PE has evolved, the role of the thoracic surgeon has become even more important. 

“Some patients may need embolectomy or bridge therapy with veno-arterial extracorporeal membrane oxygenation, both of which are performed by surgeons. Surgeons should be involved early, and there should be a plan and a back-up plan,” said Dr. Rali. 

The session’s debate topics were selected to help clarify the core questions for most clinicians. One debate addresses catheter-directed thrombolysis as the standard of care for submassive PE. With this relatively new modality of treatment, thrombolytic drugs are infused directly through a catheter positioned in the thrombosed pulmonary artery. Studies have shown that the approach seems to be safe in terms of risk of major bleeding (compared with full-dose systemic thrombolysis), but questions remain about the ideal timing, dosing, and duration. The lead authors for two pivotal trials of catheter-based thrombolysis—OPTALYSE-PE and SEATTLE II—will debate this issue. 

“It is an exciting time in acute venous thromboembolism,” said Dr. Tapson. “We need to continue to educate but, very importantly, also conduct high-quality clinical trials and expand the evidence base.”