Clinical Outcomes in Bypass-Preferred Patients With Chronic Limb-Threatening Ischemia

Patients who are classified as bypass-preferred by the Global Vascular Guidelines (GVG) have superior outcomes following bypass procedures than those who receive endovascular therapy (EVT). These findings were published in the Journal of Vascular Surgery.

The GVGs were published in 2019 and defined bypass-preferred patients as having Wound, Ischemia, and Foot Infection (WIfI) stages 3 to 4 and Global Anatomic Staging System (GLASS) stage III. This study was designed to evaluate outcomes of patients with chronic limb-threatening ischemia (CLTI) who were defined as bypass preferred.

Data for this study were sourced from Kyushu University, Matsuyama Red Cross Hospital, and Saiseikai Yahata General Hospital in Japan. Bypass-preferred patients (N=715) who received EVT (n=183) or a bypass (n=156) procedure between 2015 and 2020 were evaluated for outcomes. To balance for cohort differences, a propensity score-matching approach was used for a final sample size of 84 patients in each treatment group.

Before propensity matching, the EVT and bypass cohorts had mean ages of 78.0 (SD, 10.2) and 73.0 (SD, 10.7) years, 55.2% and 62.2% were men, and they had body mass indices of 20.7 (SD, 3.7) and 22.3 (SD, 4.1), respectively.

The EVT and bypass cohorts were categorized as stages 3 (45.4% vs 38.5%) and 4 (54.6% vs 61.5%) according to the WIfI classification (P =.23), stages 3 (26.2% vs 9.0%) and 4 (37.2% vs 52.6%) according to the GLASS femoropopliteal classification (P <.01), stages 3 (12.6% vs 12.8%) and 4 (73.8% vs 62.8%) according to the GLASS infrapopliteal classification (P =.10), and P1 (73.2% vs 63.5%) and P2 (12.0% vs 7.1%) according to the GLASS inframalleolar classification (P <.01).

Among the propensity-matched cohorts, bypass procedures were associated with increased rates of limb salvage (P <.01), wound healing (P <.01), freedom from major adverse limb events (P <.01), and freedom from reintervention (P <.01) at 730 days compared with EVT.

In the multivariate analyses, major amputation was associated with EVT (hazard ratio [HR], 3.72; P <.01), serum albumin level decrease (HR, 2.61; P <.01), and WIfI classification increase (HR, 1.56; P =.04).

Among the EVT group, major amputation was associated with congestive heart failure (HR, 2.83; P <.01), serum albumin level decrease (HR, 2.35; P <.01), GLASS inframalleolar classification increase (HR, 1.86; P =.04), and WIfI classification increase (HR, 1.65; P =.03).

Decreased likelihood of wound healing was associated with EVT (HR, 0.56; P <.01), serum albumin level decrease (HR, 0.60; P <.01), WIfI classification increase (HR, 0.68; P <.01), GLASS inframalleolar classification increase (HR, 0.73; P =.01), and GLASS infrapopliteal classification increase (HR, 0.89; P =.02).

Study limitations include the study design and potential for selection bias. Social determinants of health are also not examined by the investigators.

“Bypass surgery provides better limb salvage and wound healing in patients with WIfI Stage 3 to 4 and GLASS Stage III, which is classified as bypass-preferred category by the GVG,” the study authors wrote.