Initial endovascular therapy improves amputation-free survival in critical limb ischaemia patients
Initial treatment with endovascular therapy results in better amputation-free survival in patients with critical limb ischaemia compared with open surgical bypass, according to a study presented at the American Heart Association Scientific Session 2018 (AHA 2018), held in Chicago, Illinois.
In contrast, the endovascular-first approach appears to be associated with a higher rate of reintervention.
Of 16,800 participants (mean age 71±12 years; 59 percent male) with a lower extremity wound, 10,830 received initial endovascular therapy (mean age 70±12 years; 59 percent male) while 5,970 (mean age 71±12 years; 59 percent male) underwent initial open surgical bypass. Those in the endovascular-first group were slightly but significantly younger than patients in the open surgery group (p<0.001). [AHA 2018, abstract 75]
At baseline, congestive heart failure was reported in 18 percent of the total sample and was more common in the endovascular-first group (19 percent vs 15 percent; p<0.001). The same was true for renal failure (36 percent vs 24 percent; p<0.001) and coronary artery disease (36 percent vs 32 percent; p=0.007), while diabetes mellitus was more common in the open bypass group (44 percent vs 30 percent; p<0.05).
After propensity weighting, Kaplan-Meier analysis with inverse probability weighting showed that amputation-free survival was significantly worse in patients who underwent open surgical bypass (hazard ratio [HR], 1.16; 95 percent CI, 1.12–1.2), with the disadvantage persisting up to 80 months after the procedure.
On the other hand, open surgical bypass was associated with significantly better freedom from revascularization procedures compared with the initial endovascular treatment (HR, 0.87; 0.83–0.91).
Moreover, the revascularization experience of a medical centre is an important factor for improved outcomes. Cox proportional hazards modelling showed that relative to high-volume centres, initial treatment with endovascular therapy (HR, 1.25; 1.14–1.36) or open surgical bypass (HR, 1.30; 1.16–1.46) in medium-volume centres led to significantly worse amputation-free survival.
Similar findings were reported for initial treatment at a centre with low (endovascular therapy: HR, 1.23; 1.06–1.42; open surgical bypass: HR, 1.13; 0.93–1.38) or no (endovascular therapy: HR, 1.07; 0.93–1.23; open surgical bypass: HR, 1.49; 1.19–1.87) revascularization experience.
Aside from the difference in experience in dealing with such cases, researchers explained that this finding may also “be due to improved resources at high-volume centres.”
For the present study, researchers accessed California state-wide data to identify all patients with lower extremity ulcers and who had been diagnosed with peripheral artery disease/diabetes mellitus. Those who underwent a revascularization procedure from 2005 to 2013 were eligible for inclusion, while those with diabetes mellitus alone were excluded.
“Critical limb ischaemia remains a difficult disease to treat with limited level-1 data,” said researchers. “For patients with evidence of arterial disease, revascularization is essential to improve blood flow and allow healing.”
The findings of the present study suggest that while initial endovascular therapy is superior in terms of amputation-free survival, there is a need for better strategies to reduce its failure rate, researchers continued. “Transfer to high-volume centres should be considered early to decrease risk of amputation death.”
There is also a need for future studies to determine whether or not early recognition and intervention through revascularization results in lower amputation risks, they added.