Global Consensus Recommendations on Improving the Safety of Chronic Total Occlusion Interventions.

Safety is of critical importance to chronic total occlusion (CTO) percutaneous coronary intervention (PCI). This global consensus statement provides guidance on how to optimise the safety of CTO) PCI, addressing the following 12 areas: 1. Set-up for safe CTO PCI; 2. Guide catheter--associated vessel injuries; 3. Hydraulic dissection, extraplaque haematoma expansion, and aortic dissections; 4. Haemodynamic collapse during CTO PCI; 5. Side branch occlusion; 6. Perforations; 7. Equipment entrapment; 8. Vascular access considerations; 9. Contrast-induced acute kidney injury; 10. Radiation injury; 11 When to stop; and, 12. Proctorship. This statement complements the global CTO crossing algorithm; by advising how to prevent and deal with complications, this statement aims to facilitate clinical practice, research, and education relating to CTO PCI.

Impact of minimum contrast media volumes during percutaneous coronary intervention for chronic total occlusion lesion.

Contrast media exposure is associated with contrast-induced nephropathy (CIN) following percutaneous coronary intervention (PCI) of chronic total occlusion (CTO). Aim of this study is to assess the utility of minimum contrast media volume (CMV ≤ 50 mL) during CTO-PCI for CIN prevention in patients with chronic kidney disease (CKD). We extracted data from the Japanese CTO-PCI expert registry; 2863 patients with CKD who underwent CTO-PCI performed from 2014 to 2020 were divided into two groups: minimum CMV (n = 191) and non-minimum CMV groups (n = 2672). CIN was defined as an increased serum creatinine level of ≥ 25% and/or ≥ 0.5 mg/dL compared with baseline levels within 72 h of the procedure. In the minimum CMV group, the CIN incidence was lower than that in the non-minimum CMV group (1.0% vs. 4.1%; p = 0.03). Patient success rate was higher and complication rate was lower in the minimum CMV group than in the non-minimum CMV group (96.8% vs. 90.3%; p = 0.02 and 3.1% vs. 7.1%; p = 0.03). In the minimum CMV group, the primary retrograde approach was more frequent in the case of J-CTO = 1,2 and 3-5 groups compared to that in non-minimum CMV-PCI group (J-CTO = 0; 11% vs. 17.7%, p = 0.06; J-CTO = 1; 22% vs. 35.8%, p = 0.01; J-CTO = 2; 32.4% vs. 46.5%, p = 0.01; and J-CTO = 3-5; 44.7% vs. 80.0%, p = 0.02). Minimum CMV-PCI for CTO in CKD patients could reduce the incidence of CIN. The primary retrograde approach was observed to a greater extent in the minimum CMV group, especially in cases of difficult CTO.

Definitions and Clinical Trial Design Principles for Coronary Artery Chronic Total Occlusion Therapies: CTO-ARC Consensus Recommendations.

Over the past 2 decades, chronic total occlusion (CTO) percutaneous coronary intervention has developed into its own subspecialty of interventional cardiology. Dedicated terminology, techniques, devices, courses, and training programs have enabled progressive advancements. However, only a few randomized trials have been performed to evaluate the safety and efficacy of CTO percutaneous coronary intervention. Moreover, several published observational studies have shown conflicting data. Part of the paucity of clinical data stems from the fact that prior studies have been suboptimally designed and performed. The absence of standardized end points and the discrepancy in definitions also prevent consistency and uniform interpretability of reported results in CTO intervention. To standardize the field, we therefore assembled a broad consortium comprising academicians, practicing physicians, researchers, medical society representatives, and regulators (US Food and Drug Administration) to develop methods, end points, biomarkers, parameters, data, materials, processes, procedures, evaluations, tools, and techniques for CTO interventions. This article summarizes the effort and is organized into 3 sections: key elements and procedural definitions, end point definitions, and clinical trial design principles. The Chronic Total Occlusion Academic Research Consortium is a first step toward improved comparability and interpretability of study results, supplying an increasingly growing body of CTO percutaneous coronary intervention evidence.

The Effect of Aggressive Wire Recanalization in Calcified Atheroma and Dilatation (ARCADIA) Technique in Eccentric Calcified Lesion of No-stenting Zone.

PURPOSE: The endovascular approach for eccentric calcified lesions of the no-stenting zone is challenging. This study aimed to investigate the effect of a novel technique for these lesions. METHODS: We performed EVT for severe and eccentric calcified lesions using the technique, which is presented previously and named aggressive wire recanalization in calcified atheroma and dilatation (ARCADIA). In brief, a guidewire is passed to the residual lumen firstly. Next, another guidewire is advanced into and cross through the calcified plaque and returned to the distal original lumen with intravascular ultrasound (IVUS) guided. The calcified plaque is dilated by using a scoring-balloon or non-compliant balloon. RESULTS: Consecutive 14 peripheral artery disease patients with isolated and eccentric calcification in a no-stenting zone were treated using ARCADIA technique between January 2018 and March 2020. In IVUS data, lumen cross-section area was significantly increased from 5.2 ± 2.0 mm2 to 18.1 ± 6.9 mm2 (p < 0.01), lumen area was expanded roundly evaluating as symmetry index from 0.45 ± 0.09 to 0.81 ± 0.12 (p < 0.01). There were no distal embolization and perforation after ARCADIA technique. One-year target lesion revascularization occurred in only 2 cases. The primary patency of 1 year was 85.7%. CONCLUSION: ARCADIA technique is safe and appropriate, and can be 1 option to treat for eccentric calcified lesions of the no-stenting zone as an optimal wire crossing method.

Predictors of prolonged guidewire manipulation time for native coronary chronic total occlusion percutaneous coronary intervention via primary antegrade approach.

OBJECTIVES: This study aimed to identify the predictive factors for the guidewire manipulation time (GWMT) of ≥20 and 30 min for chronic total occlusion-percutaneous coronary intervention (CTO-PCI) via the primary antegrade approach (PAA). BACKGROUND: Selection of primary retrograde approach (PRA) and the optimal timing to switch from antegrade to retrograde approach for coronary CTO-PCI is still debatable. METHODS: Using the Japanese CTO-PCI expert registry data, we selected and analyzed 4461 patients who underwent CTO-PCI via PAA alone. The considerable lesion/anatomical factors for GWMT ≥20 and 30 min were analyzed. The risks of prolonged GWMT ≥20 and 30 min were stratified as easy, intermediate, difficult, and very difficult according to the multivariate analysis. RESULTS: Nine lesion/anatomical characteristics (blunt stump, side branch at proximal cap, bifurcation at the exit point, calcification, tortuosity, occlusion length ≥ 20 mm, reattempt, nonleft anterior descending artery (nonleft anterior descending artery [LAD]), and tandem CTO) were independent predictors of GWMT ≥20 min (all p < 0.05). Excluding the nonLAD and tandem CTO, the same factors of GWMT ≥20 min correlated with GWMT ≥30 min (all p < 0.05). The distributions were increased in easy, intermediate, difficult, and very difficult subsets of GWMT ≥20 min (58.3%, 77.2%, 89.1%, and 100%) and GWMT ≥30 min (47.5%, 69.2%, 83.9%, and 100%). CONCLUSIONS: These predictive factors of prolonged GWMT should be assessed before CTO-PCI via PAA and when considering an adequate timing to switch the retrograde or PRA if clinically available.

Efficacy of drug-coated balloon angioplasty after directional coronary atherectomy for coronary bifurcation lesions (DCA/DCB registry).

OBJECTIVES: To evaluate the efficacy and safety of additional drug-coated balloon (DCB) angioplasty after directional coronary atherectomy (DCA) for coronary bifurcation lesions. BACKGROUND: The optimal therapy for bifurcation lesions has not been established, even in the drug-eluting stent era. DCA possibly prevents plaque and carina shift in bifurcation lesions by plaque debulking; however, the efficacy of combined DCA and DCB (DCA/DCB) for bifurcation lesions remains unclear. METHODS: This multicenter registry retrospectively recruited patients with bifurcation lesions who underwent DCA/DCB and follow-up angiogram at 6-15 months. The primary endpoint was the 12-month target vessel failure (TVF) rate. The secondary endpoints were procedure-related major complications, major cardiovascular events at 12 months, restenosis at 12 months, target lesion revascularization (TLR) at 12 months, and target vessel revascularization (TVR) at 12 months. RESULTS: We enrolled 129 patients from 16 Japanese centers. One hundred and four lesions (80.6%) were located around the left main trunk bifurcations. No side branch compromise was found intraoperatively. Restenosis was observed in three patients (2.3%) at 12 months. TLR occurred in four patients (3.1%): 3 (2.3%) in the main vessel and 1 (0.8%) in the ostium of the side branch at 12 months. TVF incidence at 12 months was slightly higher in 14 patients (10.9%), and only two patients (1.6%) had symptomatic TVR. One patient (0.8%) had non-target vessel-related myocardial infarction. CONCLUSIONS: Our data suggested that DCA/DCB provided good clinical outcomes and minimal side branch damage and could be an optimal non-stent percutaneous coronary intervention strategy for bifurcation lesions.

Randomized Trial Evaluating Percutaneous Coronary Intervention for the Treatment of Chronic Total Occlusion.

BACKGROUND: Procedural results for percutaneous coronary intervention (PCI) in coronary vessels with chronic total occlusion (CTO) have improved in recent years, and PCI strategies have moved toward more complete revascularization with more liberal use of CTO-PCI. However, evidence evaluating CTO-PCI is limited to observational studies and small clinical trials. METHODS: In this open-label, multicenter, randomized, noninferiority trial, PCI-eligible patients were assigned to receive either 1 of 2 strategies: PCI or no PCI for the qualifying de novo CTO lesion with the option for PCI of obstructive non-CTO lesions at the discretion of the operator. The primary end point was a composite of death, myocardial infarction, stroke, or any revascularization. Health-related quality of life was assessed at baseline and at 1, 6, 12, 24, and 36 months. Because of slow recruitment, the trial was stopped before completion of the 1284 planned enrollments. RESULTS: Between March 2010 and September 2016, 834 patients were randomly assigned to the CTO-PCI (n=417) or no CTO-PCI (n=398) strategy. Among the patients assigned to the no CTO-PCI strategy, 78 (19.6%) crossed over to receive staged CTO-PCI within 3 days of randomization. The overall CTO-PCI success rate was 90.6%. Serious nonfatal complications associated with CTO-PCI occurred in 3 patients (1 stroke, 1 cardiac tamponade, and 1 patient with recurrent episodes of ventricular tachyarrhythmia induced by intracoronary thrombus). Approximately half of the patients in each group underwent PCI for an average of 1.3 non-CTO lesions, resulting in a comparable residual SYNTAX score (Synergy Between PCI With TAXUS and Cardiac Surgery; 3.7±5.4 versus 4.0±5.9, P=0.42) confined to non-CTO vessels. During a median follow-up of 4.0 years (interquartile range, 2.4 to 5.1 years), there was no significant difference between the CTO-PCI and the no CTO-PCI strategies in the incidence of the primary end point (22.3% versus 22.4%, hazard ratio, 1.03; 95% CI, 0.77 to 1.37; P=0.86). Both CTO-PCI and no CTO-PCI strategy were associated with significant improvements but without between-group differences in disease-specific health status that was sustained through 36 months. CONCLUSIONS: CTO-PCI was feasible with high success rates. There was no difference in the incidence of major adverse cardiovascular events with CTO-PCI versus no CTO-PCI, but the study was limited by low power for clinical end points and high crossover rates between groups. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT01078051.

Guiding Principles for Chronic Total Occlusion Percutaneous Coronary Intervention.

Outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) have improved because of advancements in equipment and techniques. With global collaboration and knowledge sharing, we have identified 7 common principles that are widely accepted as best practices for CTO-PCI. 1. Ischemic symptom improvement is the primary indication for CTO-PCI. 2. Dual coronary angiography and in-depth and structured review of the angiogram (and, if available, coronary computed tomography angiography) are key for planning and safely performing CTO-PCI. 3. Use of a microcatheter is essential for optimal guidewire manipulation and exchanges. 4. Antegrade wiring, antegrade dissection and reentry, and the retrograde approach are all complementary and necessary crossing strategies. Antegrade wiring is the most common initial technique, whereas retrograde and antegrade dissection and reentry are often required for more complex CTOs. 5. If the initially selected crossing strategy fails, efficient change to an alternative crossing technique increases the likelihood of eventual PCI success, shortens procedure time, and lowers radiation and contrast use. 6. Specific CTO-PCI expertise and volume and the availability of specialized equipment will increase the likelihood of crossing success and facilitate prevention and management of complications, such as perforation. 7. Meticulous attention to lesion preparation and stenting technique, often requiring intracoronary imaging, is required to ensure optimum stent expansion and minimize the risk of short- and long-term adverse events. These principles have been widely adopted by experienced CTO-PCI operators and centers currently achieving high success and acceptable complication rates. Outcomes are less optimal at less experienced centers, highlighting the need for broader adoption of the aforementioned 7 guiding principles along with the development of additional simple and safe CTO crossing and revascularization strategies through ongoing research, education, and training.

Efficacy of plaque debulking for bifurcated or ostial lesions by directional coronary atherectomy prior to second-generation drug eluting stenting.

OBJECTIVES: We sought to evaluate the efficacy of plaque debulking by directional coronary atherectomy (DCA) prior to second-generation drug-eluting stent (DES) implantation for bifurcated coronary lesions. BACKGROUND: Percutaneous coronary intervention (PCI) for bifurcated lesions still remains complex and challenging in terms of restenosis or stent thrombosis regardless of whether simple or complex stenting is used. METHODS: Patients with bifurcated lesions were enrolled in this prospective multicenter registry. Pre-second-generation DES plaque debulking with a novel DCA catheter (ATHEROCUT®, Nipro Co., Osaka, Japan) was conducted. All patients were scheduled to perform a follow up angiography (9-12 month coronary angiography or coronary computed tomography). The primary end point was target vessel failure (TVF) at follow up. Secondary end points were procedure-related events and major adverse cardiac events at 1 year. RESULTS: A total of 77 patients with bifurcated lesions were enrolled. PCI with DCA was performed successfully in all cases without any major procedure-related event and only one case required complex stenting. The TVF rate at 9-12 month follow up was 3.9% (3 of 77) and those were all associated with revascularization of the target vessel. Restenosis was only observed at the ostium of the main-branch in three cases. No death, coronary artery bypass grafting, or myocardial infarction were reported for any patients within the first year. CONCLUSION: DCA before second-generation DES implantation can possibly avoid complex stenting and provide a good mid-term outcome in patients with bifurcated lesions.

Advances in CrossBoss/Stingray use in antegrade dissection reentry from the Asia Pacific Chronic Total Occlusion Club.

Antegrade dissection reentry with Stingray device (Boston Scientific, Marlborough, MA) accounts for 20-34% of the chronic total occlusion (CTO) cases in the various hybrid operators' CTO registries and is an important component of CTO crossing algorithms. The Stingray device can facilitate antegrade dissection and reentry, however its use is low outside North America and Europe. The Asia Pacific CTO Club along with three experience Stingray operators from the US, Europe and India, created an algorithm guiding use of the CrossBoss and Stingray catheter. This APCTO Stingray algorithm defines when to use the CrossBoss and Stingray device recommending a reduction in CrossBoss use except for in-stent restenosis lesions and immediate transition from knuckle wiring to the Stingray device. When antegrade wiring fails, choice of Stingray-facilitated reentry versus parallel wiring depends on operator experience, device availability, cost concerns, and anatomical factors. When the antegrade wire enters the subintimal space, we recommend using a rotational microcatheter to produce a channel and deliver the Stingray balloon-so called the "bougie technique." We recommend early switch to Stingray rather than persisting with single wire redirection or parallel wire. We recommend choosing a suitable reentry zone based on preprocedural computer tomography or angiogram, routine use of stick and swap, routine use of Subintimal TRAnscatheter Withdrawal (STRAW) through the Stingray balloon, and the multi stick and swap technique. We believe these techniques and algorithm can facilitate incorporation of the Stingray balloon into the practice of CTO interventionists globally.

Retrograde Versus Antegrade Approach for Coronary Chronic Total Occlusion in an Algorithm-Driven Contemporary Asia-Pacific Multicentre Registry: Comparison of Outcomes.

BACKGROUND: The use of a retrograde approach and algorithm-driven CTO (chronic total occlusion) percutaneous coronary intervention (PCI) has become widespread, and many registries have reported good results. This study established a new algorithm and applied it to current CTO practice and collected a CTO registry to document the results. It compared the outcomes of a retrograde versus antegrade approach in a contemporary multicentre CTO registry. METHODS: Between 1 January 2016 and 31 December 2016, consecutive patients who underwent CTO PCI performed by eight high-volume CTO operators were included in a registry. RESULTS: During this period, 485 patients with 497 CTOs were treated with technical and procedural success rates of 93.8% and 89.9%, respectively. Antegrade and retrograde technical success was 95.9% and 91.2% (p = 0.03), respectively. Procedural success for antegrade and retrograde was 94.4% and 84.6%, respectively (p < 0.001). The pure retrograde success rate was 80% and pure antegrade success rate was 75%. Technical success in different Japanese Chronic Total Occlusion (JCTO) score groups was 100% (JCTO 0), 96.2% (JCTO 1), 95.3% (JCTO 2), and 92.5% (JCTO ≥ 3), with no statistical difference in success rates between different JCTO scores. In-hospital major adverse cardiac event (MACE) was 3.8% and more common in the retrograde group (6.6% vs 1.5%). CONCLUSIONS: The retrograde approach, when used by experienced operators who have been well trained in retrograde approach, can produce higher retrograde success in complex CTO lesions. The use of an algorithm approach can improve procedural efficiency, reduce contrast and radiation dosage, and reduce the time spent in failure mode. These tools remain vital to the development of future CTO PCI.

Procedure failure of chronic total occlusion percutaneous coronary intervention in an algorithm driven contemporary Asia-Pacific Chronic Total Occlusion Club (APCTO Club) multicenter registry.

OBJECTIVE: With the evolution of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) technique and equipment, the success rate of CTO PCI has improved over the years. We examined the failed cases in this expert registry and looked at the mode of failure. METHODS: In 2016, consecutive CTO PCI performed by eight high volume CTO with an agreed CTO algorithm were examined in a registry. RESULTS: There was a total of 485 patients with 497 CTOs were treated with technical and procedural success rates of 93.8% and 89.9%, respectively. The mean J-CTO score was 2.9 ± 1.2. The main mode of failure in cases with only antegrade attempt was inability to wire to true lumen despite advanced antegrade wiring technique for example, parallel wiring or IVUS guided wiring (10 out of 11 cases). The mode of failure in retrograde attempt was: 30% was due to inability to wire the collateral channel; 30% was due to failed reverse controlled antegrade and retrograde subintimal tracking (CART); 30% was due to inability to cross CTO by retrograde microcatheter. Four cases were terminated prematurely due to procedure complications. CONCLUSION: Similar to previous reported studies, primary failure mode of only antegrade attempt was inability to wire to true lumen. However, contrary to other registries where failure to cross the retrograde channel with wire was the predominant failure mode, the retrograde failure mode was equally divided between failure to cross the channel with wire, failure to do reverse CART, and failure to cross the CTO with the microcatheter.

Assessment of reattempted percutaneous coronary intervention strategy for chronic total occlusion after prior failed procedures: Analysis of the Japanese CTO-PCI Expert Registry.

OBJECTIVES: We aimed to investigate strategies for reattempted percutaneous coronary interventions (PCIs) for chronic total occlusions (CTOs) by highly skilled operators after a failed attempt. BACKGROUND: Development of complex techniques and algorithms has been standardized for CTO-PCI. However, there is no appropriate strategy for CTO-PCI after a failed procedure. METHOD: From 2014 to 2016, the Japanese CTO-PCI Expert Registry included 4,053 consecutive CTO-PCIs (mean age: 66.8 ± 10.9 years; male: 85.6%; Japanese CTO [J-CTO] score: 1.92 ± 1.15). Initial outcomes and strategies for reattempted CTO-PCIs were evaluated and compared with first-attempt CTO-PCIs. RESULTS: Reattempt CTO-PCIs were performed in 820 (20.2%) lesions. The mean J-CTO score of reattempt CTO-PCIs was higher than that of first-attempt CTO-PCIs (2.86 ± 1.03 vs. 1.68 ± 1.05, p < .001). The technical success rate of reattempt CTO-PCIs was lower than that of first-attempt CTO-PCIs (86.7% vs. 90.8%, p < .001). Regarding successful CTO-PCIs, the strategies comprised antegrade alone (reattempt: 36.1%, first attempt: 63.8%), bidirectional approach (reattempt: 54.4%, first attempt: 30.3%), and antegrade approach following a failed bidirectional approach (reattempt: 9.4%, first attempt: 5.4%). Parallel wire technique, intravascular ultrasound guide crossing, and bidirectional approach technique were frequently performed in reattempt CTO-PCIs. Reattempt CTO-PCIs showed higher rates of myocardial infarction (2.1% vs. 0.9%, p < .001) and coronary perforation (6.9% vs. 4.2%, p = .002) than first-attempt CTO-PCIs. CONCLUSIONS: The technical success rate of reattempt CTO-PCIs is lower than that of first-attempt CTO-PCIs. However, using more complex strategies, the success rate of reattempt CTO-PCI can be improved by highly skilled operators.

Chronic Total Occlusion Wiring: A State-of-the-Art Guide From The Asia Pacific Chronic Total Occlusion Club.

OBJECTIVE: Despite the advances in wire technology and development of algorithm-driven methodology for chronic total occlusion (CTO) intervention, there is a void in the literature about the technical aspects of CTO wiring. The Asia Pacific CTO Club, a group of 10 experienced operators in the Asia Pacific region, has tried to fill this void with this state-of-the-art review on CTO wiring. METHODS: This review explains, for proximal cap puncture: choices of wires, shaping of the wire, use of dual lumen catheter, and method of step-down of wire penetration force for successful wiring. In wiring the CTO body, the techniques of loose tissue tracking, intentional intimal plaque tracking, and intentional subintimal wiring are described in detail. For distal lumen wiring, a blunt distal cap, presence of a distal cap side branch, calcium, and sharp tapered distal stump predict cap toughness, and wire penetration force should be stepped-up in these cases. The importance of choosing between redirection, parallel wiring, and Stingray (Boston Scientific, Marlborough, MA, USA) for angiographic guidance is discussed along with which will be more successful. On the retrograde side, the problems encountered with distal cap puncture and methods to overcome these problems are explained. The method of wiring the CTO body through a retrograde approach depending on the morphology of the CTO is described. Different reverse controlled antegrade and retrograde tracking (CART) wiring methods - including end balloon wiring, side balloon entry, and conventional reverse CART - are explained in detail. CONCLUSION: This is a systematic CTO wiring review, which is believed to be beneficial for CTO operators worldwide.

Impact of the Clinical Frailty Scale on Outcomes After Transcatheter Aortic Valve Replacement.

BACKGROUND: The semiquantitative Clinical Frailty Scale (CFS) is a simple tool to assess patients' frailty and has been shown to correlate with mortality in elderly patients even when evaluated by nongeriatricians. The aim of the current study was to determine the prognostic value of CFS in patients who underwent transcatheter aortic valve replacement. METHODS: We utilized the OCEAN (Optimized Catheter Valvular Intervention) Japanese multicenter registry to review data of 1215 patients who underwent transcatheter aortic valve replacement. Patients were categorized into 5 groups based on the CFS stages: CFS 1-3, CFS 4, CFS 5, CFS 6, and CFS ≥7. We subsequently evaluated the relationship between CFS grading and other indicators of frailty, including body mass index, serum albumin, gait speed, and mean hand grip. We also assessed differences in baseline characteristics, procedural outcomes, and early and midterm mortality among the 5 groups. RESULTS: Patient distribution into the 5 CFS groups was as follows: 38.0% (CFS 1-3), 32.9% (CFS4), 15.1% (CFS 5), 10.0% (CFS 6), and 4.0% (CFS ≥7). The CFS grade showed significant correlation with body mass index (Spearman's ρ=-0.077, P=0.007), albumin (ρ=-0.22, P<0.001), gait speed (ρ=-0.28, P<0.001), and grip strength (ρ=-0.26, P<0.001). Cumulative 1-year mortality increased with increasing CFS stage (7.2%, 8.6%. 15.7%, 16.9%, 44.1%, P<0.001). In a Cox regression multivariate analysis, the CFS (per 1 category increase) was an independent predictive factor of increased late cumulative mortality risk (hazard ratio, 1.28; 95% confidence interval, 1.10-1.49; P<0.001). CONCLUSIONS: In addition to reflecting the degree of frailty, the CFS was a useful marker for predicting late mortality in an elderly transcatheter aortic valve replacement cohort.

The inherent catastrophic traps in retrograde CTO PCI.

When we learn to drive, our driving instructor tells us how to check the side mirror and turn your head to check the blind spot before changing lanes. He tells us how to stop at stop signs, how to drive in slippery conditions, the safe stopping distances, and these all make our driving safe. Similarly, when we learn PCI, our mentors teach us to seat the guiding catheter co-axially, to wire the vessel safely, to deliver balloon and stents over the wire, to watch the pressure of the guiding, in order that we perform PCI safely and evade complications. In retrograde CTO PCI, there is no such published teaching. Also many individual mentors have not had the wide experience to see all the possible complications of retrograde CTO PCI and, therefore, may not be able to warn their apprentice. As the number of retrograde procedures increase worldwide, there is a corresponding increase in catastrophic complications, many of which, we as experts, can see are easily avoidable. To breach this gap in knowledge, this article describes 12 commonly met inherent traps in retrograde CTO PCI. They are inherent because by arranging our equipment in the manner to perform retrograde CTO PCI, these complications are either induced directly or happen easily. We hope this work will enhance safety of retrograde CTO PCI and avoid many catastrophic complications for our readers and operators. © 2017 Wiley Periodicals, Inc.

Initial results of a first-in-human study on the PlasmaWire™ System, a new radiofrequency wire for recanalization of chronic total occlusions.

OBJECTIVES: To examine the safety, efficacy, and efficiency of the PlasmaWireTM System to recanalize coronary chronic total occlusions (CTO) using controlled ablation inside the CTO. BACKGROUND: The PlasmaWireTM System is a new bipolar radiofrequency (RF) wire system utilizing plasma-mediated ablation to facilitate wire crossing in CTOs. Two independent PlasmaWireTM wires are used in tandem for channel creation by applying RF energy between the tips so as to localize the ablation. METHODS: Prospective, nonrandomized, single-arm, multicenter study in seven patients with CTOs indicated for percutaneous coronary intervention (PCI). RESULTS: In this study, both wires were antegradely delivered to the distal end of CTO for antegrade re-entry in two cases and bidirectionally (antegrade and retrograde) delivered to the CTO for retrograde re-entry in five cases. In all cases, channel creation was achieved within a few seconds and was confirmed on angiogram or intravascular ultrasound (IVUS) and CTO recanalization was successfully achieved without any major adverse cardiac and cerebrovascular events (MACCE) or other minor complications. The clinical follow-up showed no clinical event at 1 month. CONCLUSIONS: The PlasmaWireTM System was shown to be safe and effective in obtaining CTO recanalization through a re-entry channel utilizing plasma-mediated ablation while reducing procedure time. The PlasmaWire™ System is a new bi-polar RF wire system utilizing plasma-mediated ablation for channel creation to facilitate CTO recanalization. This first-in-human study in which seven patients were enrolled was conducted to demonstrate the safety, efficacy, and efficiency of this system for CTO recanalization. Channels through the CTOs were successfully created within a few seconds by applying RF energy between the tips of two independent PlasmaWireTM wires and recanalization was achieved in all cases without any complication. The PlasmaWireTM System may safely facilitate CTO recanalization with less vessel injury and improve initial results of CTO PCI while reducing procedure time.

The first clinical experience with a novel directional coronary atherectomy catheter: Preliminary Japanese multicenter experience.

AIMS: Despite development of drug eluting stents (DES), percutaneous coronary intervention (PCI) for bifurcation lesions using DES alone remains challenging. The aim of this study was to report on the initial clinical experience with a novel directional coronary atherectomy (DCA) catheter. METHODS AND RESULTS: Patients with de novo bifurcation lesions were entered into a prospective registry and a novel DCA catheter was used. Device, procedural success and in-hospital outcomes were evaluated. A total of 14 patients with bifurcation lesions were enrolled. DCA was performed successfully in all cases without any major procedure-related events (device success rate: 100%, procedural success rate: 100%). Four patients (29%) were treated without stent implantation and simple stenting was achieved in the other 10 patients. No in-hospital major adverse cardiac event was observed. CONCLUSIONS: PCI with a novel DCA catheter for bifurcation lesions may be safe and effective. The clinical significance of these findings needs to be determined in future studies. This study was performed to evaluate the safety and efficacy of a novel directional coronary atherectomy catheter for bifurcation lesions. Both the device and procedural success rates were 100%. Complex stenting could be avoided in all cases. No inhospital major adverse cardiac event was observed. The novel directional coronary atherectomy catheter may be safe and effective for bifurcation lesions, even in this drug eluting stent era. © 2016 Wiley Periodicals, Inc.

Independent predictors of retrograde failure in CTO-PCI after successful collateral channel crossing.

OBJECTIVES: To evaluate factors for predicting retrograde CTO-PCI failure after successful collateral channel crossing. BACKGROUND: Successful guidewire/catheter collateral channel crossing is important for the retrograde approach in percutaneous coronary intervention (PCI) for chronic total occlusion (CTO). METHODS: A total of 5984 CTO-PCI procedures performed in 45 centers in Japan from 2009 to 2012 were studied. The retrograde approach was used in 1656 CTO-PCIs (27.7%). We investigated these retrograde procedures to evaluate factors for predicting retrograde CTO-PCI failure even after successful collateral channel crossing. RESULTS: Successful guidewire/catheter collateral crossing was achieved in 77.1% (n = 1,276) of 1656 retrograde CTO-PCI procedures. Retrograde procedural success after successful collateral crossing was achieved in 89.4% (n = 1,141). Univariate analysis showed that the predictors for retrograde CTO-PCI failure were in-stent occlusion (OR = 1.9829, 95%CI = 1.1783 - 3.3370 P = 0.0088), calcified lesions (OR = 1.9233, 95%CI = 1.2463 - 2.9679, P = 0.0027), and lesion tortuosity (OR = 1.5244, 95%CI = 1.0618 - 2.1883, P = 0.0216). On multivariate analysis, lesion calcification was an independent predictor of retrograde CTO-PCI failure after successful collateral channel crossing (OR = 1.3472, 95%CI = 1.0614 - 1.7169, P = 0.0141). CONCLUSIONS: The success rate of retrograde CTO-PCI following successful guidewire/catheter collateral channel crossing was high in this registry. Lesion calcification was an independent predictor of retrograde CTO-PCI failure after successful collateral channel crossing. Devices and techniques to overcome complex CTO lesion morphology, such as lesion calcification, are required to further improve the retrograde CTO-PCI success rate. © 2016 Wiley Periodicals, Inc.

Complications during retrograde approach for chronic coronary total occlusion: Sub-analysis of Japanese multicenter registry.

OBJECTIVES: This study was performed to determine the complications occurring during retrograde percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) based on analysis of the multicenter, prospective, nonrandomized Retrograde Summit registry. BACKGROUND: Retrograde PCI for CTO has improved treatment success rates, but several complications related to the retrograde approach have been reported, including collateral channel injury and donor artery injury due to their use as retrograde roots. METHODS: This registry included data from 1,166 patients who underwent retrograde PCI for CTO in 28 Japanese centers between January 2009 and December 2011. RESULTS: Overall procedure success and retrograde procedure success were achieved in 985 (84.5%) and 838 (71.9%) of the 1,166 patients, respectively. In-hospital major adverse cardiac and cerebrovascular events (MACCE) occurred in 18 (1.5%) of the 1,166 patients. With regard to complications related to the retrograde approach, channel injury occurred in 111 (9.5%) of the 1,166 patients, but treatment was required in only 24 (2.1%) patients and subsequent cardiac tamponade occurred in only 4 (0.3%) patients. Donor artery problems occurred in only 10 (0.9%) of the 1,166 patients. In sub-analysis regarding the types of collateral channels, the septal channel was significantly safer than epicardial channel because of the lower frequency of non-Q-wave myocardial infarction (non-QMI) and channel injury requiring treatment. CONCLUSIONS: The MACCE rate during retrograde PCI for CTO determined from the Retrograde Summit registry was low and the frequency of complications related to the retrograde approach was acceptable. © 2015 Wiley Periodicals, Inc.