Surgical aneurysm repair ‘becoming more complex’
MedWire News: Surgical repair of abdominal aortic aneurysms (AAAs) has become increasingly complex with the advent of endovascular repair techniques, say US researchers, although they remain confident that outcomes of open repair can still be good in high-volume centers.
Their conclusions are based on a retrospective review of 1188 elective AAA repairs performed at one such high-volume center, Brigham and Women's Hospital in Boston, Massachusetts.
Brigham and Women's Hospital is an academic medical center where all surgeons offer both open and endovascular repair. However, the latter is generally recommended to those patients who are candidates for either technique.
For this study, Michael Belkin and co-authors compared outcomes from two time spans. The first was 1995-2004, when AAAs were typically repaired using open surgery, and the second was 2004-2010, when endovascular repair became popular.
Overall, open repair accounted for 70% of procedures in this analysis, report Belkin et al in the Annals of Vascular Surgery. However, the proportion of repairs performed with open surgery declined steadily from 1998 (when endovascular repair was introduced) until 2007.
Over the same period, the proportion of open repairs that required suprarenal cross-clamping increased significantly from 14% in 1995-2004 to 50% by 2010, Belkin et al note.
Unadjusted mortality increased between the first and second time periods in patients managed with open surgery and infrarenal clamping (from 0.62% to 1.73%) as well as in those managed with open surgery and suprarenal clamping (from 1.22% to 3.98%).
Adjusting for potential confounders caused both time trends to become nonsignificant, however.
Finally, rates of major complications and major comorbidities among patients managed with open surgery were largely unchanged between the two time periods.
"The findings of this study reinforce the idea that open surgical repair has become more challenging in the contemporary endovascular repair era," write the researchers. "Specifically, we found a significant increase in the need for suprarenal cross-clamping… as well as increased blood loss during these cases."
Nevertheless, they say that differences in complications and comorbidities appear not to be clinically relevant, and stress that aneurysm morphology remains the most important determinant of surgical approach.
They conclude: "Risk-adjusted comparisons of patient survival, major complications, and length of stay at our institution suggest that these outcomes may remain consistently good at high-volume aortic surgery centers.
"Increasing complexity among these open surgical cases suggests the need for condition-specific risk-adjustment models as well as regionalization of care to high-volume centers."
By Joanna Lyford