The Impact of Electrical Calf Muscle Stimulation on the Residual Venous Obstruction in Patients Finished Standard Anticoagulation

Abstract

during the last 4 weeks. Primary endpoints were MWD on a treadmill (3.2 km/h, 10% incline) and disease specific quality of life (Qol) measured with the VascuQol questionnaire after 1 year follow-up. Analysis was performed according to the intention-to-treat principle. To take into account the repeated measurements structure of the data differences between MWD and VascuQol sumscore were assessed with a linear mixed model with a Toeplitz covariance structure. Results -Between November 2010 and May 2015, 114 patients were allocated to SET, 126 to PTA. Compliance to SET was poor; after 1 month 75/114 (66%) patients attended the program, declining to 68/114 (60%) and 57/114 (50%) after 3 and 6 months, respectively. Ten (8%) of the patients allocated to PTA did not receive the intervention, which was technically successful in 112/116 (97%) of the remaining patients. Five patients had a minor complication after PTA and 6 a major complication necessitating endovascular or surgical resolution. Some 90/114 (79%) patients allocated to SET completed one year follow-up, and 104/126 (83%) allocated to PTA. The mean MWD improved from 187 to 561 meters in the SET group and from 196 to 574 meters in the PTA group, (p¼0.693) The VascuQol sumscore improved from 4.24 in the SET group to 5.58, and from 4.28 in the PTA group to 5.88, (p¼0.048). Yet, in both groups the improvement in VascuQol sumscore was more than the minimally important clinical difference of 1.19 (derived from 100 participants of the SUPER study). Some 33/114 (29%) of patients allocated to SET had a PTA within one year, and 2/114 (2%) additional surgical revascularization (SR). Some 10/126 (8%) patients allocated to PTA had an additional PTA within one year and another 10/126 (8%) had SR. Conclusion -Both a strategy of immediate PTA, and SET with deferred PTA in case of SET failure improve MWD on a treadmill and disease specific Qol of patients with IC due to an iliac artery obstruction. It seems reasonable to start with SET in these patients and accept a 30% failure rate. The cost-effectiveness analysis of this RCT will further define clinical decision making.