Tag Archives: TEVAR

Early Vs Delayed Thoracic Endovascular Repair

Back in the day, the only way to fix a broken thoracic aorta was via left thoracotomy.  This was a big procedure, with the possibility of several major complications, with postop paraplegia being one of them. At the time, there was a debate about whether the procedure should be done immediately versus waiting until the patient was well-resuscitated. The concern was that death was nearly certain if the aortic lesion progressed.

We learned that temporizing with strict blood pressure control worked wonders at protecting the patient. Although many of these injuries were managed within hours, a growing number were delayed by a few days to improve outcomes.

Nowadays, thoracic endovascular aortic repair (TEVAR) is routine and much less morbid than the open procedure. However, the same question arises: do it early or wait a while? Interestingly, not one but two analyses have been published on this very topic in the last four months!

The first is from an international research group that searched the usual databases and initially found 921 records. They included only clinical trials or cohort studies with ten or more adult patients that could be stratified as early (within 24 hours) or late (after 24 hours) intervention. After applying these criteria, only seven studies remained for analysis.

There were 3,757 patients with early repairs, compared to 1,238 undergoing late repair. The presenting demographics and injury grades were similar in each group. However, the short-term mortality was significantly higher (1.9x) in the early TEVAR group. Additionally, ICU length of stay was significantly longer (3 days) in the late TEVAR group.

The second paper was presented as a quick-shot at last year’s AAST meeting. It is from a group of researchers from our big Boston trauma centers and the Netherlands. They used four years of data from the TQIP database, giving them extra information unavailable in the first study. They specifically looked at patients with grade II or III injuries. Here is the grading scale:

Here are the factoids:

  • A total of 1,339 patients were studied, with about three-quarters in the early TEVAR group
  • Median time to TEVAR was 4 hours in the early group and 65 hours in the late group
  • Patients in the early group were significantly less likely to have brain or liver injuries
  • ISS was similar in both groups
  • The early TEVAR group had significantly higher in-hospital mortality (16% vs. 5%), significantly higher risk of ARDS (7.6% vs. 2.1%), but significantly shorter ICU stay (7 vs 10 days)
  • When patients who died within the first 24 hours were excluded, the in-hospital mortality remained significantly higher, and the ICU and hospital lengths of stay were significantly shorter

Bottom line: Some society guidelines began recommending delayed TEVAR in 2015. This study did not detect any trend toward this, however. Using different methods and databases, these two studies identified nearly identical mortality and ICU trends in large groups of patients. The mortality trends do not appear to be related to injury grade, overall injury severity, or the presence of head injury. 

Taken together, this suggests that we need to rethink the timing of TEVAR in patients with grade II or III injuries. The best timing still needs to be defined, but it appears to be beyond 24 hours. Centers performing this procedure should review their results and consider extending procedure timing as additional research is done to define the ideal time interval.

References:

  1. Early Versus Delayed Thoracic Endovascular Aortic Repair for Blunt Traumatic Aortic Injury: A Systematic Review and Meta-Analysis. Cureus. 2023 Jun 28;15(6):e41078. doi: 10.7759/cureus.41078. PMID: 37519486; PMCID: PMC10375940.
  2. Early Versus Delayed Thoracic Endovascular Aortic Repair for
    Blunt Thoracic Aortic Injury: A Propensity Score-Matched Analysis. Ann Surg 278:e848-e854, 2023.

 

AAST 2019 #8: Timing Of Thoracic Aortic Injury Repair

Over the past two decades, there has been a massive swing from open repair of blunt thoracic aortic injury to thoracic endovascular aortic repair (TEVAR). Although technically a bit more complex, it has decreased both morbidity and mortality significantly. The usual push in fresh trauma patients is to take care of all the life-threatening injuries as soon as possible. And from the days of the open thoracic procedure, this was generally warranted.

However, the optimal timing of repair during the age of TEVAR is not as clear. Is it really necessary to go crashing into the angio or hybrid suite to get this taken care of? Or should it wait until the patient is not as physiologically damaged? The group at University of Texas at San Antonio looked at experience in the National Trauma Databank for some guidance. They reviewed four years of data from 2012 to 2015. Patients who arrested in or prior to arrival in the ED were excluded. Mortality was the primary outcome of interest, but complications and hospital length of stay (LOS) was also noted.

Here are the factoids:

  • Nearly 6,000 patients with blunt thoracic aortic injury were identifed, and 1,930 (33%) underwent TEVAR, 2% were opened, and 65% were managed nonoperatively
  • Looking only at TEVAR patients, 69% underwent the procedure within 24 hours, 24% after 24 hours, and the remainder were not recorded (!)
  • Mortality was significantly higher in the early TEVAR group (6.4% vs 2.1%)
  • Hospital LOS was significantly shorter in the early TEVAR group (18 vs 22 days)
  • Logistic regression controlling for hypotension, severe TBI, ISS and older age confirmed the significantly lower mortality in the delayed group

The authors concluded that delayed (>24 hrs) TEVAR was associated with decreased mortality but longer length of stay.

This is a nice, clean abstract to read. The hypothesis and results are easy to understand and make sense. And it’s exactly the kind of poster that makes you think a bit. 

The only real downside is that it is an NTDB study, so there is very limited ability to go back and tease out why these results should be true. These results should push the authors to set up a more prospective study so they can figure out why this should be true. We can certainly speculate that it helps to temporize with good blood pressure control while cleaning up other major injuries and correcting deranged physiology. But one never knows until the right study is actually done.

Here are my questions for the presenter and authors:

  • Were you able to glean any insights into the associations you identified from the other data in the NTDB records you used? This could help design a really good study to see if your impressions are true.
  • The fact that a quarter of patients had TEVAR at an unknown time throws a big monkey wrench in your results. Can you use any statistical tricks to see if assuming they were either early or late would influence your results. Is it possible that this unknown group could completely neutralized your study?

I’m very excited by this one, and I don’t normally get too excited by posters. Great work!

Reference: Timing of repair of blunt traumatic thoracic aortic injury: results from the National Trauma Databank. AAST 2019, Poster #5.

Long-Term Experience With Endovascular Aortic Repair For Trauma

For decades, the treatment of blunt injury to the thoracic aorta was open repair. The big debate at the time was use of cardiac bypass vs fast clamp and sew. But starting in 1997 with the introduction of thoracic endovascular aortic repair (TEVAR) of this injury, we have rapidly moved to the point where most traumatic aortic injuries are repaired using this technique.

A report that was written nearly a decade ago indicated a relatively high complication rate for the procedure. Graft complications were reported in 18% of patients, with 14% showing endoleaks. Stroke and left arm ischemia were also reported.

The diagram above shows insertion for management of an aneurysm, but the technique is similar for trauma. Blunt aortic injury occurs closer to the left subclavian artery and care must be taken to place the endograft closer to but not covering its orifice.

As the insertion systems and stents improved, short term events have been on the decline. Unfortunately, long term followup data has been hard to come by.

Until now. An article that is not yet in print reports 11 years of experience and followup with patient undergoing TEVAR at the ShockTrauma center in Baltimore.

Here are the factoids:

  • 88 patients underwent TEVAR during the study period, all from blunt trauma
  • Average ISS was 38, showing these patients were severely injured
  • Overall mortality was 7%, but none was due to the TEVAR procedure
  • TEVAR-related complication rate was 9% Endoleaks at the ends of the graft occurred in 4 patients, and all required repair. There were 4 other minor leaks that resolved on their own.
  • 26 had all or part of the left subclavian orifice covered at initial operation. None developed ischemia, although 2 had a prophylactic carotid-subclavian bypass before TEVAR.
  • The longest followup imaging occurred 8 years after the procedure. No long-term complications were noted.

Bottom line: TEVAR has essentially replaced open repair of the aorta, except in special cases. We continue to learn from our experience, and the complication rate is still falling. Other than endoleaks recognized in the postop period, most other complications rarely occur. Long term followup is poor, but in the patients who do return, there were no complications. But remember, this is an expected sampling bias. If the patient had major problems and/or died, they would just be lost to followup. We would never know.