Hitting the spot: EVAR for rAAA should be ‘treatment of choice’ in 2021

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Frank Veith

If the equipment and requisite skillset are available, and a patient’s anatomy is suitable, endovascular aneurysm repair (EVAR) for ruptured abdominal aortic aneurysms (rAAAs) “should be the treatment of choice in 2021 and beyond,” vascular titan Frank Veith, MD, argued during the keynote address at the 2021 Critical Issues America (CIA) meeting in Miami last month.

A low mortality rate of around 20% “and the many inoperable cases that can be treated successfully with EVAR” show that the procedure is “a better way to treat rAAAs in anatomically suited patients,” Veith, professor of surgery at NYU Grossman School of Medicine and the Cleveland Clinic, told the aortic endografting conference (April 16–17).

In a talk entitled, “The evolution of EVAR for ruptured AAAs: From black sheep to the treatment of choice,” the man behind the first EVAR performed in the United States back in 1992 said the minimally invasive procedure is “intuitively better,” with the reason to pursue it the high mortality and morbidity from standard open surgical repair. “It minimizes dissection, cuts blood loss, avoids hypothermia, avoids vessel injury and avoids coagulopathy,” Veith explained.

“It’s so obvious, one wonders why endografts were not used sooner to treat ruptured AAAs. Well, the answer was simple: In the beginning, it took time to procure endografts in emergent situations, we had the solution, our own surgeon-made MEGS [Montefiore Endovascular Grafts System] endograft, which could be prepared and kept sterile in our operating rooms to treat emergent situations.”

History

Taking the CIA audience on a nearly 20-year historical retrospective, Veith discussed the evolution of EVAR and grafts. “Because this MEGS graft could be sterilized ahead of time, and kept in the operating room for urgent cases, we were able to do the first EVAR for a rAAA anywhere in the world in April 1994.”

The patient in question was inoperable, he pointed out, because of a hostile abdomen and bad heart. “He was in shock and severe pain. His angiogram showed clear evidence of free rupture, and we were able to treat him with our surgeon-made MEGS graft. His aneurysm was successfully excluded, and the patient survived for more than three years, only to die of his comorbidities.”

Through 1994 and 1995, Veith and colleagues treated another 11 patients considered at prohibitive risk for open repair.

“Surprisingly for us in these very sick patients, there were only two deaths, giving us a remarkable 17% operative mortality. These favorable early results in impossibly high-risk patients led us to the hypothesis in 1995 that endografts and other image-guided endo techniques should be employed to treat all rAAAs, even in good-risk patients. From 1994 to 2000, almost no one else in the world agreed with us. They almost all felt that open repair was the best treatment for all ruptured aneurysms.”

Onward to 2005, Veith said his institution and a few others produced results suggesting that EVAR improved outcomes for rAAAs. He noted, however, that other groups had experienced poor results deploying EVAR for rAAAs. “So it’s fair to say that as of 2009, EVAR for rAAAs remained controversial, and there were many who said we need a randomized controlled trial [RCT] comparing EVAR to open repair in this setting.”

Yet, Veith argued, it is the treatment strategies, adjuncts and techniques—outlined, he said, in a 2009 Annals of Surgery paper— that make a difference, “and may account for the better results, which some groups could achieve.”

Randomized trials

The controversy persisted at least until 2016, Veith continued, culminating in continued calls for RCTs. Three such trials have been completed: ECAR (Endovasculaire ou chirugie dans les anévrysmes aorto-iliaques rompus) in France, AJAX (Amsterdam acute aneurysm trial) in the Netherlands, and IMPROVE (The immediate management of the patient with ruptured aneurysm: Open versus endovascular repair) in the U.K.

“All three trials claimed no difference in 30-day mortality between EVAR and open repair,” said Veith. “However, that conclusion is, in my opinion, flawed, misleading and just plain wrong. Here is why: The ECAR and AJAX trials excluded high-risk patients in shock and too sick for open repair, and those are precisely the patients most likely to benefit from EVAR.”

The larger IMPROVE trial, Veith continued, concluded that a strategy of endovascular repair was not associated with significant reduction in 30-day or one-year mortality. “Here is why this conclusion is misleading: Even though there was no 30-day mortality significant difference between the EVAR strategy group and the open repair group, one has to see the details to appreciate the flaws in IMPROVE,” he said.

“One key flaw is that of the 316 patients randomized to endovascular strategy, only 154 were actually treated by EVAR—that’s less than half. Their mortality was around 27%. While in the same group, those patients getting an open repair actually had a higher mortality of 38%.”

Veith added, “So, to me, it seems that the IMPROVE trial clearly shows that EVAR is the better treatment for rAAA patients, if it can be done. In addition, the most recent results from IMPROVE confirm EVAR’s superiority, with better long-term survival overall with EVAR and better short- and long-term survival in women.”

RCTs, he concluded, “are not always the infallible holy grail they are thought to be. As with everything else in this world, how you do EVAR for rAAAs matters, including some of the strategies and technical tips I have shown you today.”

NICE guidelines

Later in the same session, Bijan Modarai, MB BS, a consultant vascular surgeon at Guy’s and St. Thomas’ NHS Foundation Trust in London, England, presented an update on the controversial NICE (National Institute for Health and Care Excellence) AAA guidelines published in March 2020 that recommended open repair for most patients.

Modarai revisited both the draft and finalized document. While discussing “highly critical feedback” to the initial draft, he pointed out stakeholders had commented that “one cannot provide EVAR for ruptured aneurysm if there is no elective service as the infrastructure would simply not be present.”

Session moderator Mark Farber, MD, chief of the division of vascular surgery at the University of North Carolina, Chapel Hill, probed Veith on the importance of education and access to expertise. “This gets back to the NICE guidelines,” Veith said. “If you’re not doing elective EVAR, you can’t do emergency EVARs. It’s really education all the way.”

Benjamin W. Starnes, MD, University of Washington, Seattle, chief of vascular surgery, added: “When the anesthesiologists finally saw that we could do these awake under local anesthesia, and they saw the outcomes, they were flabbergasted.”

CX rAAA debate

Meanwhile, a debate at the recent 2021 Charing Cross Symposium (CX; April 19–22), featured a similar theme, focusing on the topic, “Emergency endovascular aneurysm repair is the standard of care for rAAA,” which was proposed by Hans-Henning Eckstein, MD, a professor of vascular and endovascular surgery at the Technical University of Munich, Germany.

“We all know that aortic rupture is a life-threatening condition, so survival is the therapeutic aim number one,” he said. “Since we know from trials that EVAR is safer than open aortic repair in elective rAAA therapy, the question arises whether emergency EVAR is also safer than open aortic repair for rAAAs.” The answer is yes, he said. “It’s more an issue of how to do emergency EVAR than simply inferiority or superiority,” Eckstein added.

“Current guidelines clearly recommend emergency EVAR over open aortic repair in anatomically suitable patients,” he said. “Emergency EVAR has significantly lower mortality and morbidity rates, and therefore emergency EVAR should be considered the new standard of care for rAAA.”

Arguing against the motion, R. Clement Darling III, MD, chief in the division of vascular surgery at Albany Medical Center in New York, said: “What happens to those patients with hostile necks or unsuitable necks, or have poor access? Those patients might be better suited for open repair than endovascular repair, and I think that’s one of the limitations we have seen in single series studies.”

The standard of care for rAAAs requires that “you can stop the bleeding in an expeditious fashion, whether it is by clamping the aorta or by aortic occlusion balloons,” he continued.

“And don’t forget that 30% of the mortality for open aneurysms historically has been because of venous injuries trying to get proximal aortic control, so the balloon is truly a game changer. You need to reconstruct the aorta no matter whether you use EVAR or open [repair], and the goal really is to have a live, viable patient for discharge.”

Ruptured AAAs, Darling said, is a “systems problem”— and not merely a procedure solution. “We need a system that has access to both the surgical skills for open and endovascular care for optimal results. It is not EVAR that is the only answer for the best results in rAAA repair.”

A CX audience poll sided with Eckstein by 64% to 36%. “I think that [the poll result] reflects what’s going on in the community—granted, both speakers did a good job in presenting the case,” session moderator Gustavo S. Oderich, MD, professor and chief of vascular and endovascular surgery at the University of Texas Health Science Center at Houston, added.

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