Abstract 18668: The Clinical Impact of Post Procedural Peripheral Vascular Flow Reserve on Wound Healing Following Infrapopliteal Intervention in Patients with Critical Limb Ischemia

Abstract

Background: The impaired coronary blood flow reserve after coronary intervention has been related to microvascular impairment leading to increased morbidity and mortality. We evaluated whether this finding can be generalised to patients with critical limb ischemia (CLI) undergoing endovascular treatment (EVT) for infrapopliteal arterial disease. Methods: Eleven limbs (Rutherford 4 and 5) from 10 patients of CLI with angiographic evidence of infrapopliteal arterial disease underwent measurement of peripheral vascular flow reserve (VFR). A pressure/temperature sensor-tipped guidewire was positioned in the proximal popliteal artery at 5cm distal to the guiding catheter. With 3 mL of saline at room temperature used as an indicator, by hand-injection, thermodilution curves in the infrapopliteal artery were obtained both at baseline and at intra-arterial papaverine-induced maximum hyperemia (30mg). VFR was calculated from the ratio of inverse mean transit times at hyperemia and baseline. The VFR measurements were performed both before and after EVTs. Wound healing was defined as the progressive reduction in wound surface area from the beginning of the study. Results: The procedure success rate was 100%, and VFR was measured in all patients without any complication. Wound healing was achieved in 6 limbs after EVT (healing group) and not achieved in 5 (non-healing group). The average pre- and post-VFR was 4.1±2.6 and 5.8±4.2 respectively. There was no significant difference in pre-VFR values between healing and non-healing group (4.3±3.2 versus 3.7±2.0). However, post-VFR values was significantly higher in the healing group than in the non-healing group (6.3±4.1 versus 3.3±1.8, p<0.05). VFR values in non-healing group decreased or remained unchanged in all patients mainly due to increase in resting blood flow. Conclusions: VFR values immediately after EVT for infrapopliteal arterial disease remained unchanged in patients with poor wound healing mainly due to increase in resting blood flow. This finding suggests that a therapeutic effect can not be obtained if the arteriolar bed is damaged after EVT. This easily assessable VFR is useful in clinical risk stratification for patients with CLI immediately after EVT in the catheterization laboratory.