INDIANAPOLIS – Reintervention rates following endovascular repair of abdominal aortic aneurysms have fallen steadily with the introduction of each successive generation of endografts, while reintervention rates after open surgical repair remained stable during a recent 15-year period.
This was among the key findings from the first in-depth analysis of reinterventions occurring in contemporaneous cohorts of abdominal aortic aneurysm (AAA) patients undergoing endovascular aneurysm repair (EVAR) or open repair. The large single-center retrospective study demonstrated major differences between the two treatment strategies in terms of the incidence, nature, timing, and mortality associated with complications requiring reintervention, Dr. Mustafa Al-Jubouri said at the annual meeting of the American Surgical Association.
Dr. Al-Jubouri of Jobst Vascular Institute, Toledo, Ohio, reported on the 1,144 patients who underwent AAA repair there during 1996-2011. Forty-nine percent had EVAR, 51% open surgical repair. Beginning in 2003, more EVARs than open repairs were done annually at the Toledo institute, consistent with the experience at many major centers in the United States and elsewhere, where EVAR has become the first-line treatment based upon evidence that it offers lower operative mortality, less blood loss, and shorter ICU and hospital lengths of stay.
These advantages come at a cost, however: namely, a greater rate of secondary interventions, mainly due to device migration, failure, or endoleaks. The purpose of Dr. Al-Jubouri’s study was to evaluate the rates and reasons for reintervention over time in the two cohorts, as well as the impact of reintervention on long-term survival.
Reintervention was required in 13.6% of the EVAR group during a mean follow-up of 4.58 years, and in 5.1% of the open surgery group during 6.58 years. A single reintervention occurred in 7.9% of EVAR patients and 3.6% of the open repair group. More than one reintervention was required in 5.8% of EVAR patients compared to just 1.6% of the open repair group.
The types and timing of complications leading to reintervention were very different in the two groups. Sixty-eight percent of reinterventions in the EVAR group were for treatment of endoleaks. Another 11.5% were to address device migration, and an equal number were for occlusion.
In contrast, the three most frequent causes of reintervention in the open repair group were colonic ischemia, accounting for 30.4% of reintervention procedures; severe bleeding, 21.7%; and incisional hernia, which triggered another 21.7% of reinterventions.
Notably, 60% of all reinterventions in the open repair group occurred during the initial hospitalization, while less than 7% of reinterventions in the EVAR patients happened within 1 month of the index procedure and only one-third within the first year, the surgeon continued.
Thirty-day mortality in EVAR patients who underwent reintervention within the first month was zero, compared to a 23.3% mortality rate in open repair patients requiring reintervention within 1 month. However, when patients did not require early reintervention, 30-day mortality rates in the two groups did not differ significantly: 1.9% in EVAR group and in the open repair group. That means when patients in the open surgery group required early reintervention, their mortality rate shot up sevenfold.
After the first 30 days post-index procedure, long-term survival rates in the two groups were similar.
Need for reintervention in the open repair group was strongly related to larger aneurysm size. In contrast, reintervention rates were similar in the EVAR group regardless of aneurysm size.
A first reintervention after EVAR occurred in 23.7% of patients who received a first-generation endograft, such as the Ancure or Talent; in 16.2% of those who got the second-generation AneuRx endograft; and in 9.1% with a third-generation endograft, such as the Excluder, Endurant, Powerlink, or Zenith. The annualized rate of reintervention during the first 3 years of follow-up was 6.8% per year with first-generation devices, 7.2% per year with second-generation endografts, and significantly lower at 3.4% per year with the third-generation.
One major reason reintervention rates in EVAR patients have declined over time is that each newer generation of endograft is lower-profile, easier to deploy, and more durable. Also, many of the surgeons now putting in third-generation endografts were performing EVAR 15 years ago; they’re very experienced operators, Dr. Al-Jubouri noted.
Discussant Dr. James R. Debord proposed another explanation for the decrease in EVAR reinterventions over time.
"Isn’t it much more likely that it’s due to recognition of the fact that many of these type 2 endoleaks that we used to intervene on early on don’t require reintervention unless there’s sac enlargement?" commented Dr. Debord, professor of clinical surgery and chief of vascular surgery at the University of Illinois at Peoria.