Balloon-Assisted Retrograde Puncture of Distal Vessels in Patients Unsuitable for a Conventional Transpedal Approach

Purpose: To describe a novel bailout technique to approach below-the-knee chronic total occlusions after a failed bidirectional recanalization attempt using the plantar loop maneuver in patients who are poor candidates for a retrograde puncture. Technique: After a failure of recanalization of the opposite tibial artery using the plantar loop maneuver, an assisted direct retrograde transpedal approach can be performed regardless of poor vessel caliber or even arterial occlusion. After crossing the plantar arch, a low profile angioplasty balloon is used as a landmark for the pedal puncture and to give guidance for the wire advancement from the new access. Conclusion: A balloon-assisted retrograde transpedal approach may be considered for below-the-knee recanalization after standard plantar loop technique failure in patients who are not candidates for conventional retrograde puncture.

First Experience With The GoBack-Catheter For Successful Crossing of Complex Chronic Total Occlusions in Lower Limb Arteries

Purpose: To evaluate the use of the GoBack-catheter (Upstream Peripheral Technologies) in complex revascularizations in lower limb arteries. Materials and Methods: In this retrospective single-center study, the results of the first 100 consecutive patients including 101 limb-revascularizations, performed between May 2018 and July 2020 with the study device, were analyzed. In all cases, guidewire-crossing failed, and all lesions were chronic total occlusions (CTO), either de novo, reocclusions, or in-stent reocclusions. Successful crossing was defined as passing the CTO using the study device. Patency at discharge and after 30 days was defined as less than 50% restenosis on duplex sonography, without target lesion revascularization. Results: Median lesion length was 24 cm and 38 patients (37.6%) had a calcium grading according to the peripheral arterial calcium scoring system (PACSS) of 4 or 5. In 20.8% of patients, an occluded stent was treated. CTOs involved the femoropopliteal segment in 91.1%, iliac arteries in 5.9%, and tibial arteries in 7.9%. The GoBack-catheter was employed for entering into or crossing through parts or the full length of a CTO or an occluded stent as well as for re-entering into the true lumen after subintimal crossing. The device was used via contralateral and ipsilateral antegrade as well as retrograde access with an overall technical success rate of 92.1%. In 3 patients minor bleeding occurred at the crossing or re-entry site, which were managed conservatively. Thirty-day adverse limb events comprised minor amputations in 4 patients (4.0%), 1 major amputation (1.0%), and reocclusions in 7 limbs (6.9%). Conclusion: The new GoBack-catheter offers versatile endovascular applicability for complex CTO recanalization in a broad range of peripheral vascular interventions with a high technical success and low complication rate.

Contemporary Strategies and Outcomes of Dedicated Chronic Total Occlusion Percutaneous Coronary Intervention Programs: A Prospective Multicentre Registry

Background. The field of CTO PCI is expanding, but successful and safe percutaneous coronary intervention (PCI) of coronary chronic total occlusions (CTO) requires a substantial resource and experience investment. We aimed to assess temporal trends in strategies and outcomes of 2 dedicated programs for CTO PCI. Methods. Between 2011 and 2020, 920 CTO PCI procedures were prospectively included at 2 referral centres in Belgium. Temporal trends were assessed, and logistic regression models were built to identify predictors of outcome. Results. Despite an increase in lesion complexity (the J-CTO score increased from 1.3 in year 1 to 1.7–2.0 in years 8-9, p < 0.001 ), technical success improved from 70.0% to 85.6% in year 9 (p value for trend <0.001). We observed the most significant improvement starting at years 3-4 (OR 2.3 in year 4 versus year 1, p = 0.018 ). Together with an increase in success rates and lesions complexity, there was an increase in the use of dual injections, retrograde approaches, the number of balloons and stents, and the use of microcatheters. Conversely, there was a decrease in large bore access, an increase in radial approach, and a shift towards contemporary dissection/reentry techniques. This strategy resulted in a stable major complication rate of 4.7% (p value for trend 0.33). The rate of coronary procedure-related myocardial injury was high (71.0%) and was associated with the use of more intracoronary devices. Conclusions. Three to four years after initiation of a dedicated CTO PCI program with 50 CTO PCIs per year, consistent high technical success and low complication rates are achieved using contemporary strategies.

The “needle re-entry” technique for infrainguinal arterial calcified occlusive lesions

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.

401 Myocardial viability and ischaemia assessment in chronic coronary total occlusions according to collaterals distribution: a retrospective analysis

Aims Whether CTO-PCI (chronic total occlusions—percutaneous coronary intervention) offers clinical benefit over optimal medical therapy is still a matter of debate. Viability and ischaemia assessment could improve selection of candidates to PCI. Traditionally, well-developed collaterals are considered a marker of myocardial viability in CTO territory. Current literature offers few data concerning the relationship between viability/ischaemia and collaterals distribution. Methods and results We retrospectively analysed the Cardiovascular Magnetic Resonance (CMR) studies and coronary angiographies of patients with at least one CTO referred at Humanitas Research Hospital between June 2009 and September 2020. We included 131 patients who underwent CMR with LGE assessment; of them, 111 (85%) underwent stress-CMR with adenosine. AHA segments (16 segment/patient for a total of 2096 segment assessed) were assessed on three short axis projection and scored for WMSI on cine images, for the presence of ischaemia on first pass perfusion, and for viability on LGE images. Viability was defined as LGE transmurality ≤50% and WMSI (wall motion score index) &gt;1. Patients were divided in three groups according to collaterals distribution at coronary angiography: Patients with TD collaterals were more likely to have viable segments in the CTO-territory (90% of the segments in TD, 76% in WD, and 71% in PD, coeff. 0.107, P &lt; 0.001). No statistically significant differences were found between groups as regard the amount of ischaemic segments (61% of the segments in TD, 65% in WD, and 60% in PD, P = 0.189). Conclusions The presence of myocardial viability is slightly associated with the degree of coronary collateralization at coronary angiography while the amount of ischaemia is not. Stress CMR should be considered in CTO patients before a reopening attempt.

Canadian Multicenter Chronic Total Occlusion Registry: Ten-Year Follow-Up Results of Chronic Total Occlusion Revascularization

Background: Chronic total occlusions (CTO) occur in nearly 20% of coronary angiograms. CTO revascularization, either by percutaneous coronary intervention (PCI) or coronary artery bypass grafting surgery (CABG), is infrequently performed, approximately one-third of cases. Long-term outcomes are unknown. The objective of the study was to determine whether early CTO revascularization of patients, either by CABG or PCI, was associated with improved clinical outcomes. Methods: One thousand six hundred twenty-four patients from the Canadian CTO registry were followed for at least 9.75 years. Revascularization was performed according to routine clinical practice. Patients were grouped according to CTO revascularization status (PCI or CABG of CTO vessel, CTO revasc) or no CTO revasc (medical therapy only, or PCI/CABG of non-CTO vessels only), within 3 months of initial angiogram. Patients were followed for mortality, revascularization procedures (PCI and CABG), and hospitalizations for acute coronary syndromes and heart failure. Results: Early CTO revasc was performed in 28.2% of patients (17.5% CABG, 10.7% PCI). The CTO revasc group was younger, with more males and generally fewer comorbidities. There was a significantly lower mortality probability at 10 years in the CTO revascularization group (22.7% [95% CI, 19.0%–26.9%]) compared with the no CTO revasc group (36.6% [95% CI, 33.8%–39.5%]). At 10 years, revascularization rates (14.0% versus 22.8%) and acute coronary syndrome hospitalization rates (10.0% versus 16.6%) were significantly lower in the CTO revasc group. Baseline-adjusted analysis showed CTO revasc was associated with significantly lower all-cause mortality (hazard ratio, 0.67 [95% CI, 0.54–0.84]). In both landmark and time varying analyses, association with lower mortality was particularly robust for CTO revascularization by CABG (hazard ratio 0.56 and 0.60, respectively), with a marginally significant result for PCI in the time varying analysis (hazard ratio 0.711 [95% CI, 0.51–0.998]). Conclusions: Early CTO revascularization was associated with significantly lower all-cause mortality, revascularization rates, and hospitalization for acute coronary syndrome at 10 years, and mainly driven by outcomes in patients with CABG.

The “Direct tip injection in occlusive lesions (DIOL)” fashion

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.