P3395Arrival time at hyperemia of below the ankle as a determinant factor for limb salvage: evaluation by 2 dimension perfusion angiography

Abstract

Abstract Background In patients with critical limb ischemia, it is desirable to obtain enough skin perfusion pressure (SPP) levels through revascularization. 2D-perfusion angiography is an emerging technology for the quantification of tissue perfusion consisted of 6 parameters calculated by time-density curve of digital subtraction angiography (DSA). Purpose We evaluated the feasibility of 2D-perfusion angiography for below the knee (BTK) endovascular therapy (EVT). We aimed to clarify which angiographical parameters of lower limb are related to SPP after EVT. Methods Consecutive 33 limbs (mean age 74.5 years, men 55%), which successfully underwent EVT for isolated BTK lesions, were enrolled in this study. We excluded Rutherford 6 limbs with severe gangrene or tissue loss, consequently 26 limbs were Rutherford 4 or 5 critical limb ischemia. We treated total 47 lesions, including 26 chronic total occlusive lesions. 5Fr guiding sheath was advanced to popliteal artery. DSA images were obtained by mechanical contrast infusion. We quantified indexed blood flow on below the ankle area by using 2D-perfusion angiography, and examined 6 parameters [arrival time (AT), time to peak (TTP), wash-in rate, width, area under the curve and mean transit time (MTT)] from acquired DSA. Hyperemia was induced by 20mg papaverine intra-arterial infusion through the guiding sheath. Results The parameters except wash-in rate were significantly shortened after hyperemia induced by intra-arterial papaverine infusion below the ankle region. Dorsal and plantar SPP were significantly correlated with hyperemic AT, hyperemic wash-in rate and AT ratio (hyperemic/rest) of lower ankle regions after EVT. However, only AT ratio was independently associated with dorsal SPP in multivariate analysis (P=0.032). A receiver operating characteristic curve showed hyperemic AT <4.5 seconds and AT ratio <0.49 predicted to obtain SPP levels >50 mmHg after EVT with the area under the curve of 0.71 (95% confidence interval, 0.52–0.90) and 0.73 (95% confidence interval, 0.55–0.90), respectively. Representative Case of 2D-perfusion Conclusion Hyperemic AT <4.5 seconds and AT ratio <0.49 of lower ankle regions may be essential to obtain the sufficient levels of SPP for limb salvage after BTK intervention. 2D perfusion angiography technique at hyperemic condition is feasible and has the potential to monitor lower limb tissue perfusion through EVT and to optimize the interventional treatment.