The impact of diabetes on current revascularisation practice and clinical outcome in patients with critical lower limb ischaemia

The role of established and emerging risk factors in peripheral vascular graft occlusion

Several studies have evaluated the association between established as well as emerging vascular risk factors with peripheral graft occlusion. There is evidence for a link between the risk for graft occlusion and total serum cholesterol, low-density lipoprotein cholesterol and triglyceride levels. The overall effect of smoking shows a 2.35-fold increase in risk of graft failure. Studies involving diabetic patients undergoing peripheral bypass may have failed to detect higher occlusion rates, possibly due to increased morbidity and mortality as well as higher amputation rates even if the graft is patent. Both antiplatelet agents and anticoagulation seem to be effective in the prevention of graft occlusion. Unconvincing data have been published with regards to the effect of hypertension on graft patency. Emerging factors such as fibrinogen, lipoprotein (a), C-reactive protein and homocysteine levels should also be considered when assessing the risk of graft occlusion. More research is needed to prevent graft occlusion due to the obvious clinical relevance, quality of life and cost issues.

Surgical or endovascular revascularization in patients with critical limb ischemia: influence of diabetes mellitus on clinical outcome

OBJECTIVE

The optimal revascularization strategy in diabetic patients with chronic critical limb ischemia (CLI) is unclear. This study assessed the efficacy of tailored endovascular-first vs surgical-first revascularization stratified for the presence of diabetes.

METHODS

This prospective cohort study, with 1-year follow up, was conducted in a tertiary referral center in a consecutive series of 383 patients (45.7% had diabetes) presenting 426 limbs with chronic CLI. Interventions were endovascular (PTA cohort, 207 limbs) or surgical (SURG cohort, 85 limbs) revascularization. Conservatively treated patients without revascularization (NON REVASC cohort, 108 limbs) were used as a reference. The main outcome measures were sustained clinical success, defined as survival without major amputation or repeated target extremity revascularization (TER), and a categoric upward shift in clinical symptoms according to the Rutherford classification.

RESULTS

Sustained clinical success of revascularization was significantly better in nondiabetic patients (hazard ratio [HR], 0.48; 95% confidence interval [CI], 0.29 to 0.72; P = .001 [SURG cohort]; HR, 0.53; 95% CI, 0.35 to 0.78; P = .002 [PTA cohort]) compared with diabetic patients (HR, 0.78; 95% CI, 0.44 to 1.43, P = .45 [SURG cohort]; HR, 0.83; 95% CI, 0.55 to 1.27, P = .40 [PTA cohort]). Repeated TER significantly improved clinical success, which became equivalent between diabetic and nondiabetic patients (HR, 1.02; 95% CI, 0.7 to 1.4). In multivariate analysis, treatment success was not influenced by mode of initial revascularization, neither in diabetic nor in nondiabetic patients. Cumulative 1-year mortality was 30.4%, with a trend of increased mortality in patients with diabetes (HR, 1.45; 95% CI, 0.98 to 2.17; P = .064). Limb salvage rates were similar in treatment cohorts, also if stratified for diabetes (HR, 1.04; 95% CI, 0.62 to 1.75).

CONCLUSION

Diabetic patients with chronic CLI benefit from early revascularization. To achieve this benefit, multiple revascularization procedures may be required, and close surveillance is therefore mandatory. Choice of initial revascularization modality seems not to influence clinical success.