Daitaro Kanno

Background: Robotic-assisted percutaneous coronary intervention (rPCI) offers potential benefits, including improved lesion assessment, optimised stent deployment and reduced radiation exposure. However, comparative data, particularly in Japanese populations, remain limited. Aim: To compare procedural and clinical outcomes between second-generation rPCI and manual percutaneous coronary intervention (mPCI) in patients with chronic coronary syndrome and acute coronary syndrome over a 1-year follow-up period. Methods: This retrospective cohort study included 176 patients who underwent rPCI using the second-generation CorPath GRX Vascular Robotic System. Following 1:1 propensity score matching at the lesion level, 176 patients were identified in the mPCI group. The co-primary endpoints were 1-year all-cause mortality and major adverse cardiovascular events, defined as a composite of cardiac death, non-fatal MI, target lesion revascularisation, stent thrombosis and stroke. Results: Both groups had similar baseline characteristics. Compared with mPCI, rPCI was associated with shorter total procedural time (26 minutes [19–37] versus 71 minutes [52–90]; p<0.01), fluoroscopy time (14 minutes [10–18] versus 16 minutes [10–26]; p=0.04), lower contrast volume (99 [82.8–129.0] versus 141 ml [116–172]; p<0.01) and lower dose area product (3,628.3 [2,552.1–5,352.3] versus 6,349.1 [4,080.0–8,382.3]; p<0.01). At 1 year, the co-primary endpoints of all-cause mortality (p=0.33) and major adverse cardiovascular events (p=0.79) were comparable between groups. Conclusion: Compared with mPCI, rPCI was associated with shorter procedural and fluoroscopy times, lower contrast volume and lower dose area product, while demonstrating similar clinical outcomes at 1 year.

Background: Burr fracture during rotational atherectomy (RA) is a rare but potentially devastating complication. Due to its infrequency, comprehensive data on its incidence, mechanisms, and management are lacking. This study aimed to investigate the incidence, contributing factors, and management strategies for burr fractures during RA procedures.Methods: This retrospective analysis included all patients who underwent PCI with RA at a single center between January 2013 and October 2024. Data were collected from a prospective registry.Results: Among 3738 patients, three cases of burr fracture without entrapment were identified (incidence: 0.08%). Burr fractures occurred at the burr‐driveshaft junction (tip fracture) in two cases and at the driveshaft in one case. Pre‐fracture warning signs included incoherent burr‐advancer knob movement, fluoroscopic translucency, and frequent driveshaft prolapse. Significant proximal tortuosity or enlargement and non‐coaxiality between the RA device and the coronary artery were identified as potential contributing factors. In two cases involving tip fractures, simple manual traction removed the fractured burr. In the third case involving driveshaft fracture, coronary rupture necessitated covered stent implantation and urgent surgery.Conclusion: Burr fractures during RA are rare but potentially serious complications. Significant proximal tortuosity or enlargement and non‐coaxiality between the RA device and the coronary artery may increase the risk of burr fracture. Recognizing pre‐fracture warning signs and understanding the underlying mechanisms are crucial for minimizing complications and optimizing procedural safety.

A coronary hematoma, which can sometimes obstruct coronary flow, may be left behind after tip‐detection antegrade dissection and reentry. We present a novel bailout technique utilizing subintimal trans‐catheter withdrawal technique with the assistance of a stent and a balloon. This technique can be used before performing bailout long stenting or a fenestration procedure with a cutting balloon, which are standard treatments for hematoma, to improve impaired coronary flow caused by a distally extended hematoma.

Background: The successful intervention for peripheral artery disease is limited by complex chronic total occlusions (CTOs). During CTO wiring, without the use of intravascular or extravascular ultrasound, the guidewire position is unclear, except for calcified lesions showing the vessel path. To solve this problem, we propose a novel guidewire crossing with plaque modification method for complex occlusive lesions, named the “Direct tip Injection in Occlusive Lesions (DIOL)” fashion. Main text: The “DIOL” fashion utilizes the hydraulic pressure of tip injection with a general contrast media through a microcatheter or an over-the-wire balloon catheter within CTOs. The purposes of this technique are 1) to visualize the “vessel road” of the occlusion from expanding a microchannel, subintimal, intramedial, and periadventitial space with contrast agent and 2) to modify plaques within CTO to advance CTO devices safely and easily. This technique creates dissections by hydraulic pressure. Antegrade-DIOL may create dissections which extend to and compress a distal lumen, especially in below-the-knee arteries. A gentle tip injection with smaller contrast volume (1–2 ml) should be used to confirm the tip position which is inside or outside of a vessel. On the other hand, retrograde-DIOL is used with a forceful tip injection of moderate contrast volume up to 5-ml to visualize vessel tracks and to modify the plaques to facilitate the crossing of CTO devices. Case-1 involved a severe claudicant due to right superficial femoral artery occlusion. After the conventional bidirectional subintimal procedure failed, we performed two times of retrograde-DIOL fashion, and the bidirectional subintimal planes were successfully connected. After two stents implantation, a sufficient flow was achieved without complications and restenosis for two years. Case-2 involved multiple wounds in the heel due to ischemia caused by posterior tibial arterial occlusion. After the conventional bidirectional approach failed, retrograde-DIOL was performed and retrograde guidewire successfully crossed the CTO, and direct blood flow to the wounds was obtained after balloon angioplasty. The wounds heeled four months after the procedure without reintervention. Conclusions: The DIOL fashion is a useful and effective method to facilitate CTO treatment.

Background: Vascular calcification is a predictor of poor clinical outcome during and after endovascular intervention. Guidewire crossing techniques and devices have been developed, but chronic total occlusions (CTOs) with severe calcification often prevent subintimal re-entry. We propose a novel guidewire crossing approach combined needle rendezvous with balloon snare technique, named the “needle re-entry” technique, for treatment of complex occlusive lesions. Main text: A 73-year-old female with severe claudication in her right calf with ankle brachial index of 0.62, and a computed tomography angiogram showed a long occlusion with diffuse calcification in superficial femoral artery. She was referred to our department to have peripheral interventions. Since the calcified vascular wall of the lesion prevented the successful re-entry, the “needle re-entry” was performed. First, a retrograde puncture of the SFA, distally to the occlusion, was performed and an 0.018-in. guidewire with a microcatheter was inserted to establish a retrograde fashion. Second, an antegrade 5.0-mm balloon was advanced into a subintimal plane and balloon dilation at 6 atm was maintained. Third, an 18-gauge needle was antegradely inserted from distal thigh to the dilated 5.0-mm balloon. After confirming a balloon rupture by the needle penetration, we continued to insert the needle to meet the retrograde guidewire tip. Then, a retrograde 0.014-in. guidewire was carefully advanced into the needle hole, named the “needle rendezvous” technique. After further guidewire advancement to accomplish a guidewire externalization, the needle was removed. Finally, since the guidewire was passing through the 5.0-mm ruptured balloon, the balloon was withdrawn, and the guidewire was caught with the balloon and successfully advanced into the antegrade subintimal space, named the “balloon snare” technique. After the guidewire was advanced into the antegrade guiding sheath and achieved a guidewire externalization, an endovascular stent graft and an interwoven stent were deployed to cover the lesion. After postballoon dilation, an angiography showed a satisfactory result without complications. No restenosis, reintervention, and limb loss have been observed for one year follow-up period after this technique. Conclusions: The “needle re-entry” technique is a useful guidewire crossing technique to revascularize femoropopliteal complex CTOs with severe calcification which prevent the achievement of guidewire crossing with the conventional procedures.

Background: The patency achieved by conventional peripheral interventions for atherosclerotic lesions in the common femoral artery (CFA), called the “no stenting zone”, is not superior to that achieved by surgical endarterectomy due to calcified plaque occupying the area. Plaque modification strategies to obtain acute gain in CFA patency provide the better clinical outcomes than standard balloon angioplasty. Atherectomy devices, which focus on the modification of superficial calcifications, contribute to the improvement of clinical outcomes. However, deep calcifications resist vessel expansion such that luminal gain is not easily achieved. Main text: We propose a novel calcified plaque modification technique, named the “fracking technique” (FT). The term fracking refers to how a rock is fractured by the high hydraulic pressure. In this technique, deep calcifications are cracked with hydraulic pressure via a balloon indeflator through an 18-gauge needle, which punctures calcifications to achieve greater acute luminal gain. Case 1 involved an 81-year-old male with eccentric calcified plaque in the right CFA. Conventional balloon angioplasty for the lesion yielded a suboptimal minimal lumen area (MLA), which increased from 6.2 to 10.7-mm² on intravascular ultrasound (IVUS). The FT was implemented to obtain a larger MLA. After the FT was repeated at three locations at up to 8-atm, a greater MLA of 27.1-mm² was achieved without complications. Case 2 involved a 72-year-old male undergoing hemodialysis due to diabetes mellitus who presented with ischemic pain in his right limbs at rest due to severe stenosis with eccentric calcification in the distal CFA. The MLA on IVUS before and after balloon angioplasty was 10.0-mm² and 13.1-mm², respectively, and this result was still suboptimal. The FT was attempted and successfully yielded a greater MLA of 28.9-mm² without complications. Restenosis has not been detected for 2 years follow-up period. Conclusions: The FT is an effective option for treating calcified CFA lesions to achieve a larger lumen area. Long-term follow-up studies are necessary.

Background: The ideal method for recanalization of complex peripheral lesions has not been determined, despite the use of the latest endovascular devices. We describe a novel method for a fully percutaneous anatomical bypass, named the “needle bypass” technique, for treatment of complex vascular lesions with failed previous surgical therapy. Main text: A 68-year-old male patient with chronic limb-threatening ischemia presented to our department. He previously had received surgical treatment 10 years prior that included the removal of the right distal common femoral artery and two surgical bypasses, an axillary-femoral bypass and an iliofemoral bypass, because he had repeated infections. He was referred to our center in order to have peripheral interventions. Since the previous conventional bridging/revascularization of the removed common femoral bifurcation had failed, the “needle bypass” technique was then used. With this novel technique, the tips of two percutaneous and bidirectional inserted needles were aligned (“needle rendezvous”) for the externalization of a guidewire in a through-and-through manner. Once this was achieved, an endovascular stent graft and an interwoven stent were deployed to cover and connect the lesion. This new technique is a minimally invasive anatomical bypass that directly connects artery to artery without any disturbance of the venous flow, and this technique, as the only option available, was performed successfully in our no-option patient. Conclusions: The “needle bypass” technique is an effective percutaneous treatment method in patients with no other surgical options.