October 24, 2016
9 min read

Team Approach Changes Treatment of Pulmonary Embolism

The PERT concept is catching on around the world.

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Pulmonary embolism can be difficult to treat. Its implications can range from relatively benign to life-threatening and treatments range from medical management to endovascular intervention to major surgery. Today, there is little consensus in the clinical community about the best practices for treatment of patients with pulmonary embolism.

For many who treat patients with PE, the best course of action is to convene a multidisciplinary team of experts to intensively review each case and discuss how to proceed. The concept of PERT — Pulmonary Embolism Response Team — emerged in recent years.

The first PERT was formed almost 5 years ago at Massachusetts General Hospital, which coined the acronym, and has since spread to nearly 100 sites. While there are not yet enough data to determine whether the PERT concept has resulted in improved outcomes for patients with PE, experts told Cardiology Today’s Intervention that there are many cases in which it is almost certain that a patient would have been worse off had a PERT not been convened.

“The opportunity is there to make a dramatic difference,” Kenneth Rosenfield, MD, MHCDS, FACC, FSCAI, section head of vascular medicine and intervention at Massachusetts General Hospital and head of the PERT operation there, said in an interview. “For example, we’ve had several patients where activation of the PERT team led to very rapid treatment of a clot in transit that would have taken much longer otherwise. In one case, that clot in transit actually did ‘kill’ the patient and led to CPR, and the patient was saved with rapid implementation of ECMO [extracorporeal membrane oxygenation] because the PERT team had been called in.”

Kenneth Rosenfield

Underserved Population

PE can be difficult to recognize and is sometimes initially misdiagnosed. Treatment paradigms are highly variable and there is often a lack of coordination of care. For these reasons, not much progress has made in improving outcomes, and it can be very difficult to manage by a single clinician alone. These were major factors behind the impetus to develop the PERT concept at Massachusetts General Hospital, according to Rosenfield.

“Unlike the progress we’ve made in CVD, with 30% reduction in mortality, we have not made a significant impact on the incidence and outcomes of PE, at least that we know of,” he told Cardiology Today’s Intervention. “It has been very challenging to collect data in a coordinated fashion because patients are either under-recognized or treated differently by the many different providers and services that manage PE.”

This led to “a couple of signature events, a couple of patients that had very bad PE,” he said. “We [realized that] there is incredible diversity and variability in treatment of these patients and that we can do better.

“[Patients with PE] are treated differently depending on what medical or surgical service they’re on, who diagnoses the PE, who gets consulted and what that individual or service’s biases are. There is very little in the way of data-driven decisions. Part of that is because we don’t have good markers for predicting outcomes, so assignment of treatment is challenging in the absence of that. There is a paucity of markers for predicting outcomes, and in the absence of a robust evidence base assignment of treatment is challenging,” Rosenfield said.

Particularly difficult was figuring out how to manage patients who were neither well enough to be managed conservatively nor sick enough to be obvious candidates for lifesaving interventions, Michael R. Jaff, DO, FSCAI, medical director of the Fireman Vascular Center at Massachusetts General Hospital, told Cardiology Today’s Intervention.

“If you took a patient from the ‘middle group’ and put them on blood thinners, they could end up having worsening pulmonary emboli, worsening CV status and could die as a result of that decision,” he said. “They might do fine in the short term but end up with long-term chronic thromboembolic pulmonary hypertension syndrome, which has a miserable prognosis and the treatment of this is complex and risky. Those were the main limitations of our ability to make decisions and manage patients.”


Building the Team

Once the idea for a team approach to managing PE circulated at Massachusetts General Hospital, it caught on quickly because many clinicians from different departments were frustrated with how patients with PE were being managed, Jaff and Rosenfield said.

Moreover, similar team-management concepts had caught on in disciplines such as aortic valve repair and cancer treatment, so the idea made sense, they said.

“A team approach allows you to have perspective in real time, while the patient is right there in the bed, from a group of experts who come with different skills from different backgrounds with different knowledge and bring all of it to the management of that patient,” Jaff, a member of the Cardiology Today’s Intervention Editorial Board, said. “It has been very helpful, not only to reassure us when we’re making decisions, but also, if a decision is that an intervention needs to be done, the right people are on the call who know how to mobilize that staff and get things moving quickly.”

Michael R. Jaff

It was not extremely difficult to get buy-in — a torrent of volunteers emerged within a week of the initiative being publicized — but there were some logistical challenges when the team was being formed, Rosenfield said.

“However, there was enthusiasm around the table and the excitement multiplied exponentially after PERT members started participating in these multidisciplinary calls; they immediately recognized how much benefit the patients were deriving from this and, beyond this, how interesting it was for the practitioners,” he said. “At our institution, people have not been paid to be in the PERT program, yet they are actively participating. It’s a coalition of the willing.”

Activating the Team

In practice, for the team to be activated, an imaging scan must confirm a diagnosis of PE and the gravity should be at least low-risk submassive, high-risk submassive or massive, according to Rosenfield, who is also a member of the Cardiology Today’s Intervention Editorial Board and president of the Society for Cardiovascular Angiography and Interventions.

“The first point of contact at Massachusetts General Hospital is usually a fellow, who makes certain that all the pieces are in place, then touches base with the PERT attending who’s on call that day,” he said. “Then a decision is made regarding whether the case meets the threshold for calling together a multidisciplinary meeting; we have a very low threshold for that.”

Because team members’ schedules greatly differ, the team meets virtually, using the GoToMeeting platform, which enables the participants to speak by phone, review the clinical data and simultaneously view images such as CT scans and echos.

Once the team is convened, the participating members on the call, usually between four and 12, discuss all the information about the case that is at their disposal and come to a decision — sometimes by consensus, sometimes by a majority vote — about the next course of treatment.

“It is not infrequent that we initially think we know what we want to do, whether it be conservative therapy, catheter-directed lytic therapy or thrombectomy, and then during the call, that opinion gets changed and the therapeutic intervention changes based on the meeting,” Rosenfield said.

Growing the Concept

Once the PERT program took off at Massachusetts General Hospital, team members started publicizing the initiative, in a 2013 letter to the editor in Chest, a 2014 paper in Hospital Practice and at medical conferences. In short order, PERT teams were formed at other institutions.

“All of the sudden, people started approaching us and sending us email and asking us about this new approach to PE. After telling them about PERT, they started saying, ‘We’d like to do this, too.’ And they set up spontaneously their own centers,” Rosenfield said.


An early adopter was Northwestern Memorial Hospital, Chicago, where Daniel Schimmel, MD, MS, assistant professor of interventional cardiology, had had his share of frustration with how patients with PE were being managed.

Daniel Schimmel

“During my training, I cared for a patient with submassive PE. While he wasn’t in shock, he was profoundly symptomatic, short of breath while lying in bed and oxygen-dependent while walking around the room. He was a young man who needed to get back to work and return to caring for his family. None of my attendings at the time thought systemic lytics were appropriate due to the associated bleeding risks, but I also thought giving him heparin alone and waiting to see if he got better in 30 days was equally inappropriate,” Schimmel, who heads the PERT team at Northwestern Memorial Hospital, said in an interview. “Each speciality — hematology, pulmonology, cardiology and interventional radiology — had their specifiic focus, but symptom management was not part of the treatment plan. No one was really looking at the patient as a whole to optimize his outcome; not just his risk of death but also his quality of life.”

“Since my training, I have made treatment of PE a focus of my clinical and academic goals and enrolled other specialties in the vision. We meet regularly to see each other’s point of view, discuss new therapies and focus of patient-centered quality of life, in addition to mortality,” Schimmel said. “By combining our experiences, the volume that we see as a group have seen is far beyond what any one of us would have seen individually. While we may not always agree initially, we usually find consensus on a treatment plan by the end of discussing a case.”

Some initial meetings were contentious as individuals advocated for the practices common in their disciplines, but that went away over time as team members got to know each other and saw the complexities that are not often discussed in the guidelines, he said.

Soon after publication of the Hospital Practice paper, a national PERT Consortium was created, which has since been incorporated as a not-for-profit 501(c)3 organization. Two annual meetings have been held. According to Rosenfield, the first, in May 2015, attracted 85 people from 40 centers, and the second, in June, drew 150 people from nearly 80 centers. The concept has now spread outside of the United States; a few centers from Europe and South America even attended the second annual meeting, Rosenfield said.

The next PERT Consortium meeting is scheduled for June 22, 2017 in Boston. This year, the Consortium will also co-sponsor with Massachusetts General Hospital the third annual CME conference dedicated exclusively to PE on June 23-24, 2017. Information about both events is available at pertconsortium.org.

This movement has gained momentum despite skepticism remaining in some corners, Rosenfeld said. “There are some people who think PE can be treated fine with half-dose lytic therapy,” he said. “Others feel the only reason PERT teams are being set up is to generate business volume for catheter-directed therapeutic interventions. In our institution, the opposite has actually been the case; nearly three-quarters of the time we’ve decided on anticoagulation alone. As we accrue data systematically, we will be able to evaluate the impact of different therapeutic approaches.”

Effect on Patients, Outcomes

The PERT concept has been adopted widely and changed the way in which many clinicians manage patients with PE, but its biggest contribution may come in the form of finally producing reliable outcomes data for this population.

“The promise is that this will allow us ultimately to collect a large volume of high-quality data from the 800 to 100 sites that have PERT programs. Sites will also collaborate as the PERT Consortium conceives and coordinates various clinical trials,” Rosenfield said. “Massachusetts General Hospital created a registry, run by Chris Kabrhel, MD, MPH, which was accrued detailed data on 700 patients over 4 years; multiply that by 75 or 100 and you’re talking about tens of thousands of patients with PE, and that can only inform the field.”


In the meantime, the success of the PERT programs is anecdotal, but there are many anecdotes.

“I think clinicians feel a lot better having us on board, because we can break down barriers and circumvent the historical delays to appropriate therapy or testing,” Schimmel said. “We have less ambiguity over who we want to treat with invasive means and who we want to treat with systemic lytic.”

Jaff and Rosenfield both pointed to the same case when assessing the impact of the PERT program on patient outcomes: a patient from a community hospital out of state with high-risk submassive PE who could not walk more than a few steps without becoming short of breath who participated in her own PERT meeting.

“There were no data that definitely told us what to recommend, but we recommended she undergo a catheter-based intervention to try to reduce her embolic load and improve her short-term symptoms and long-term outlook,” Jaff said. “We discussed the risks of that and she made the decision during the PERT call that she wanted to proceed and wanted it done at Massachusetts General Hospital. So there was a rapid facilitation of transfer, she underwent her intervention, had no complications and was walking briskly in the woods a few days later. That was quite a rewarding experience.” — by Erik Swain

Click here to read "Challenges Presented by Pulmonary Embolism."

Disclosure: Jaff reports serving on the Data Safety Monitoring Board of a trial sponsored by Novella and holding equity in Embolitech. Rosenfield and Schimmel report no relevant financial disclosures.