Related Experiment Videos
Infrapopliteal bypasses to severely calcified, unclampable outflow arteries: two-year results
B D Misare1, F B Pomposelli, G W Gibbons
1Division of Vascular Surgery, Deaconess Hospital, Boston, MA 02215, USA.
Insights
Severe calcification of outflow arteries in infrapopliteal bypass surgery did not significantly impact graft patency or limb salvage rates. These findings suggest surgeons should not avoid distal bypass for limb salvage in cases with calcified vessels.
Area of Science:
- Vascular Surgery
- Cardiovascular Medicine
- Surgical Outcomes
Background:
- Severe, circumferential calcification of distal outflow vessels is a common challenge in infrapopliteal bypass surgery.
- The impact of such calcification on bypass graft patency remains incompletely understood.
Purpose of the Study:
- To evaluate the effect of severe outflow artery calcification on infrapopliteal bypass graft patency and limb salvage rates.
- To determine if severe calcification should be a contraindication for distal bypass in limb salvage procedures.
Main Methods:
- Retrospective review of 1957 infrapopliteal bypass grafts (1990-1995).
- Comparison of 101 grafts to severely calcified, unclampable arteries versus 105 grafts to non-calcified arteries.
- Analysis of primary and secondary patency, foot salvage, mortality, and survival rates at 24 months.
Main Results:
- Grafts to non-calcified arteries showed higher patency (74% vs 60%) and foot salvage (93% vs 77%) at 24 months compared to severely calcified arteries.
- These differences did not achieve statistical significance (log-rank analysis).
- 30-day mortality and 24-month survival rates were similar between groups.
Conclusions:
- Effective techniques allow successful infrapopliteal bypass to severely calcified outflow arteries.
- Severe calcification should not deter vascular surgeons from performing distal bypass for limb salvage.
Purpose:
Although severe, circumferential calcification of distal outflow vessels is frequently encountered, its effect on bypass graft patency rates has not been well established.
Methods:
Using a computerized vascular registry database, we conducted a retrospective review of 1957 bypass grafts with distal anastomoses to infrapopliteal vessels performed at a single institution between 1990 and 1995. Of these cases, 101 procedures involved outflow arteries classified by the operating surgeon as severely calcified and unclampable (requiring intraluminal occluders for vascular control), whereas in 105 cases the outflow arteries had no calcification present at the distal anastomotic site. The remaining cases had varying intermediate degrees of calcification and were not analyzed. Indication for bypass procedure was limb-threatening ischemia in 90% of severe calcification cases and in 84% of cases without calcification. Atherosclerotic risk factors were similar except for the presence of diabetes (92% vs 74%, p < 0.001), creatinine level > 2.0 mg/dl (21% vs 8%, p < 0.01), and dialysis dependency (17% vs 3%, p < 0.001), all of which were more prevalent in the severe calcification group. Infrapopliteal distal anastomotic location and type of conduit ( > 90% autogenous vein) were comparable between groups.
Results:
Primary patency, secondary patency, and foot salvage rates at 24 months were 60%, 65%, and 77% for the severe calcification group and 74%, 82%, and 93% for the no calcification group, respectively. With secondary procedures comprising 26% of cases in each group, data from the 150 primary procedures were reanalyzed separately. In this primary procedure group, 24-month primary patency, secondary patency, and foot salvage rates were 66%, 69%, and 77% for the severe calcification group and 84%, 90%, and 96% for the no calcification group, respectively. Although patency and salvage rates were consistently lower for the severe calcification group in all analyses, these differences did not achieve significance by log-rank life-table analysis at 2-year follow-up. Perioperative 30-day mortality (0.99% severe calcification vs 0.95% no calcification) and 24-month survival rates (84% severe calcification vs 83% no calcification) were also similar between groups.
Conclusion:
These data suggest that effective techniques exist to perform infrapopliteal bypasses to severely calcified, unclampable outflow arteries with results comparable with those obtained with clampable, uncalcified vessels. The finding of severe, circumferential calcification of outflow target arteries should not dissuade vascular surgeons from distal bypass for limb salvage indications.