Evaluation of Distal Hemodynamic Changes of Lower Extremity after Endovascular Treatment: Correlation between Measurements of Color-Coded Quantitative Digital Subtraction Angiography and Ankle-Brachial Index.

Lou, Wen-Sheng; Su, Hao-Bo; Huang, Kai-Yi; He, Xu; Chen, Liang; Chen, Guo-Ping; Shi, Wan-Yin; Han, Jing-Feng; Gu, Jian-Ping

PURPOSE To confirm the feasibility of using time-to-peak (TTP) measurements derived from color-coded digital subtraction angiography (ccDSA) imaging to assess improvements in distal circulation in relation to the ankle-brachial index (ABI). MATERIALS AND METHODS Nineteen patients who underwent percutaneous transluminal angioplasty and/or stent placement (in 20 lower extremities) were evaluated. A region of interest (ROI) at the proximal superficial femoral artery (SFA) was selected for a reference TTP for quantitative assessments. The ROI measurements of the TTP interval between medial and lateral plantar/dorsalis pedis relative to the reference was regarded as the ΔTTP and used to assess distal hemodynamic improvement achieved by the revascularization. The ABI was obtained with a handheld Doppler ultrasound machine with a manually operated blood-pressure cuff. Correlation between the two methods was analyzed. RESULTS The ABI improved significantly from 0.44 ± 0.18 to 0.79 ± 0.20 (t = 10.11; P < .0001) after the intervention. TTP, which reflected the blood flow time from the proximal SFA to the foot, became much faster, from 11.86 seconds ± 4.26 to 6.75 seconds ± 2.03 (t = 6.57; P < .001). A good correlation was observed between the improvement ratios of ΔTTP and ABI (r = 0. 863). CONCLUSIONS TTP measurements derived from ccDSA provide an easy and objective method for assessment of distal hemodynamic changes after endovascular treatment of lower-extremity peripheral arterial disease (PAD). It may provide a quantitative method to assess the adequacy of endovascular interventions and provide more objective suggestions for procedure endpoints, with potentially better clinical outcomes for patients with PAD.