Decision analysis model of open repair versus endovascular treatment in patients with asymptomatic popliteal artery aneurysms

Abstract

Objective: Repair is indicated of asymptomatic popliteal artery aneurysms (aPAAs) that are >2 cm. Endovascular PAA repair with covered stents (stenting) is increasingly used. It is, however, unclear when an endovascular approach is preferred to traditional open repair with great saphenous vein bypass (GSVB). The goal of this study was to assess the treatment options for aPAAs using decision analysis.

Methods: A Markov model was developed and a hypothetic cohort of patients with aPAAs was analyzed. GSVB, stenting, and nonoperative management with optimal medical treatment (OMT) were compared. Operative mortality, patency rates, quality-of-life values, and costs were determined by comprehensive review of the best available evidence. The main outcome was quality-adjusted life-years (QALYs). Secondary outcomes were cost-effectiveness and number of reinterventions.

Results: For a 65-year-old male patient with a 2.0-cm aPAA and without significant comorbidities, probabilistic sensitivity analysis shows that intervention is preferred over OMT (5.77 QALYs, 95% credibility interval [CI], 5.43-6.11; OMT). GSVB treatment for this patient results in slightly higher QALYs than stent placement, with a predicted 8.43 QALYs (GSVB: 95% CI, 8.21-8.64) vs 8.07 QALYs (stenting: 95% CI, 7.84-8.29), a difference of 0.36 QALYs (95% CI, 0.14-0.58). Furthermore, costs are higher for stenting ($40,464; 95% CI, $34,814-$46,242) vs GSVB ($21,618; 95% CI, $15,932-$28,070), and more reinterventions are required after stenting (1.03 per patient) vs GSVB (0.52 per patient), making GSVB the preferred strategy for all outcomes considered. Stenting is preferred in patients who are at high risk for open repair (>6% 30-day mortality) or if the 5-year primary patency rates of stenting increase to 80%. For very old patients (>95 years) and patients with a very short life expectancy (<1.5 years), OMT yields higher QALYs.

Conclusions: GSVB is the preferred treatment in 65-year-old patients with aPAAs for all outcomes considered. However, patients at high risk for open repair or without suitable vein should be considered as candidates for endovascular repair. Very elderly patients and patients with a short life expectancy are best treated with OMT. Further improvement of endovascular techniques that increase patency rates of endovascular stents could make this the preferred therapy for more patients in the future.