Search

Abstract Background Revascularization with endovascular therapy (EVT) for complex below-the-knee (BTK) chronic total occlusion (CTO) remains a challenging problem. The Japanese-BTK (J-BTK) CTO score is reported as an indicator of the difficulty of BTK CTO, with the guidewire (GW) passage success rate decreasing as the grade increases. We previously reported an effective GW crossing method for the intravascular ultrasound (IVUS)-guided parallel wiring of complex BTK CTO. In this study, we investigated the feasibility of EVT using IVUS-guided wiring for BTK CTO. Materials and methods This single center, retrospective study analyzed 65 consecutive BTK CTO vessels in which IVUS-guided wiring was attempted after the failure of a conventional antegrade wiring approach from November 2020 to November 2022. The primary endpoint was the clinical success of the target CTO vessel. The secondary endpoints were the GW success rate per grade based on the J-BTK CTO score, number of GW used for CTO crossing, fluoroscopy time, and complications. Results Target vessels were the anterior tibial artery (66.2% of cases), peroneal artery (9.2%), and posterior tibial artery (24.6%). Blunt type CTO entry was performed in 55.4% of cases, calcification of entry was observed in 24.6% of cases, the mean occlusion length was 228.2 ± 93.7 mm, mean reference vessel diameter was 2.1 ± 0.71 mm, and outflow was absent in 38.5% of cases. J-BTK CTO scores of 0/1 (grade A), 2/3 (grade B), 4/5 (grade C), and 6 (grade D) were seen in 18.5%, 43.1%, 36.3%, and 1.5% of cases, respectively. The clinical success rate was 95.4%. The GW success rate by J-BTK CTO grade was as follows: grade A (100%), B (100%), C (91.7%), and D (0%). The mean number of GW used was 3.4 ± 1.4, the mean fluoroscopy time was 72.3 ± 32.5 min, and complications occurred in 7.7% of cases. Conclusion This study showed a very high clinical success rate despite the difficulty of BTK CTO. IVUS-guided EVT might be a feasible strategy for complex BTK CTO.

Abstract Background The transradial approach (TRA) is associated with fewer serious access site-related complications compared with the transfemoral or transbrachial approach. However, TRA has associated problems in complex aortoiliac (AI) lesions, including the procedural difficulty. A bidirectional approach was used combining TRA with a sheathless technique for femoral artery (FA) puncture to treat complex AI lesions, as a minimally-invasive approach. This report describes a representative cases with AI chronic total occlusion in which the combination of TRA and a sheathless technique for FA puncture was useful for guidewire crossing. Case presentation Case 1 was a 71-year-old man with intermittent claudication (IC). Control angiography showed total occlusion of the left common iliac artery (CIA) ostium to the distal external iliac artery (EIA). Guidewire externalization was achieved by combining TRA using a 6Fr guiding sheath and a sheathless technique for the left FA. Two nitinol stents were deployed in the CIA to EIA. Case 2 was a 63-year-old man with IC. Control angiography revealed total occlusion of the right CIA ostium to the common femoral artery (CFA) with severe calcification. The antegrade wire could not pass through the CTO lesion because of the calcified CFA occlusion. A 21-G metal needle was used to penetrate the CFA calcification through the distal true lumen of the CFA, and the wire was inserted into the EIA for wire externalization. Three nitinol stents were deployed in the CIA to EIA, and a drug-coated balloon was dilated in the CFA with hemostasis of the distal puncture site. In both cases, the retrograde puncture site was hemostatic during the procedure and postoperative bed rest was not required. Conclusions TRA combined with a sheathless technique from the FA has the potential to treat AI complex lesions in a less invasive manner.

Abstract Background Although endovascular therapy is used to treat chronic limb-threatening ischemia, long chronic total occlusion (CTO) is still challenging to treat. Especially in patients with poor run-off below-the-knee (BTK) arteries, it is difficult to perform a retrograde approach, and even guidewire passage may be difficult. Case presentation We treated two cases of chronic limb-threatening ischemia using our novel extreme antegrade guidewire crossing technique by AnteOwl WR intravascular ultrasound (IVUS)-guided parallel wiring to a BTK artery (EXCAVATOR technique). Case 1 was a 70-year-old man with ulceration of the right toe. The AnteOwl WR IVUS was intentionally advanced into the subintimal space of the posterior tibial artery, and the totally intraplaque route was advanced by IVUS-guided parallel wiring that was successfully passed from the lateral plantar aspect to the true lumen of the digital artery. Case 2 was a 76-year-old woman with rest pain and cyanosis of the right lower limb. Angiography showed total occlusion from the superficial femoral artery to BTK arteries. AnteOwl WR IVUS-guided parallel wiring was repeatedly performed until the distal true lumen of the peroneal artery was reached, and revascularization was successfully achieved via the antegrade approach alone. Conclusions With its excellent crossable performance, good image quality, and high navigational ability within the CTO, the AnteOwl WR can be used to pass parallel wiring into the distal true lumen for BTK CTO.