Antegrade Dissection and Reentry as Part of the Hybrid Chronic Total Occlusion Revascularization Strategy

Comparative Analysis of Polymer Versus Non-Polymer Jacketed Wires in Chronic Total Occlusion Percutaneous Coronary Intervention

There is significant variation in wire utilization patterns for chronic total occlusion (CTO) percutaneous coronary intervention. This study aimed to compare the outcomes of polymer-jacketed wires (PJWs) versus non-PJWs in anterograde procedures. We analyzed clinical and angiographic characteristics, and procedural outcomes of 7,575 anterograde CTO percutaneous coronary interventions that were performed at 47 centers between 2012 and 2023. Cases in which PJWs were exclusively used were classified in the PJW group, whereas cases where at least one non-PJW was employed were classified in the non-PJW group. Study end points were as follows: technical success, coronary perforation, major adverse cardiac event. PJWs were exclusively used in 3,481 cases (46.0%). These cases had lower prevalence of proximal cap ambiguity, blunt stump, and moderate/severe calcification. They also had lower Japanese CTO (J-CTO), Prospective Global Registry for the Study of Chronic Total Occlusion (PROGRESS-CTO), and PROGRESS-CTO complications scores, higher technical success (94.3% vs 85.7%, p <0.001), and lower perforation rates (2.2% vs 3.2%, p = 0.013). Major adverse cardiac event rates did not differ between groups (1.3% vs 1.5%, p = 0.53). Exclusive use of PJWs was independently associated with higher technical success in both the multivariable (odds ratio [OR] 2.66, 95% confidence interval [CI] 2.13 to 3.36, p <0.001) and inverse probability of treatment weight analysis (OR 2.43, 95% CI 2.04 to 2.89, p <0.001). Exclusive use of PJWs was associated with lower risk of perforation in the multivariable analysis (OR 0.69, 95% CI 0.49 to 0.95, p = 0.02), and showed a similar trend in the inverse probability of treatment weight analysis (OR 0.77, 95% CI 0.57 to 1.04, p = 0.09). Exclusive use of PJWs is associated with higher technical success and lower perforation risk in this non-randomized series of patients.

Exploring indicators of success in chronic total occlusion percutaneous coronary intervention with Stingray system-based antegrade dissection re-entry: Insights from retrospective analysis

BACKGROUND

The predictors of success of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) through antegrade dissection and re-entry (ADR) using the Stingray system (Stingray ADR) remain elusive, mainly owing to the lack of consecutive angiographic and procedural records of patients.

OBJECTIVES

This study aimed to identify indicators that can determine the success of CTO PCI performed using the Stingray ADR technique.

METHODS

The clinical data of 115 patients who underwent CTO PCI through Stingray ADR at the same cardiac center were retrospectively and consecutively collected. Multivariate logistic regression analysis was performed to investigate the indicators of the success of ADR attempts.

RESULTS

The technical success rate of Stingray ADR in CTO PCI was 72.2%. The overall technical success rate of CTO recanalization was 78.3% in all CTO PCIs having used Stingray Low Profile balloon. Vessel calcification (odds ratio [OR]: 4.03; 95% confidence interval [CI]: 1.49-11.88; p = 0.008), and retrograde puncture indicator (OR: 4.89; 95% CI: 1.51-17.11; p = 0.009) were identified as independent positive predictors. Blunt/no stump proximal to the occlusion segment (OR: 0.22; 95% CI: 0.06-0.64; p = 0.009), decision time before Stingray ADR (per 1 h increase) (OR: 0.54; 95% CI: 0.31-0.92; p = 0.026), operation duration of Stingray ADR (per 10 min increase) (OR: 0.62; 95% CI: 0.40-0.94; p = 0.028), and puncture site at the intraplaque region (OR: 0.24; 95% CI: 0.06-0.84; p = 0.026) were identified as the four negative independent predictors.

CONCLUSIONS

This study revealed independent predictors of the success of CTO PCI performed using the Stingray ADR technique. As for CTO characteristics, the presence of calcification in the CTO segment and a tapered stump proximal to the lesion site can facilitate successful Stingray ADR. As for the procedures, the success rate of Stingray ADR can be improved by initiating the technique decisively and promptly, operating the system quickly and accurately and creating a puncture in the distal cap region of CTO under retrograde guidance.

Trends and Outcomes of Antegrade Dissection and Re-Entry in Chronic Total Occlusion Percutaneous Coronary Intervention

BACKGROUND

The contemporary frequency and outcomes of antegrade dissection and re-entry (ADR) for chronic total occlusion (CTO) percutaneous coronary intervention (PCI) have received limited study.

OBJECTIVES

The aim of this study was to determine the frequency and outcomes of ADR use in a large multicenter CTO PCI registry.

METHODS

The characteristics and outcomes of ADR were examined among 12,568 patients who underwent 12,841 CTO PCIs at 46 U.S. and non-U.S. centers between 2012 and 2023.

RESULTS

ADR was used in 2,385 of the procedures (18.6%). ADR use declined from 37.9% in 2012 to 14.5% in 2022 (P < 0.001). Patients in whom ADR was used had a high prevalence of comorbidities. Compared with cases that did not use ADR, ADR cases had more complex angiographic characteristics, higher mean J-CTO (Multicenter CTO Registry in Japan) score (2.94 ± 1.11 vs 2.23 ± 1.26; P < 0.001), lower technical success (77.0% vs 89.3%; P < 0.001), and higher in-hospital major adverse cardiac events (3.7% vs 1.6%; P < 0.001). The use of the CrossBoss declined from 71% in 2012 to 1.4% in 2022 and was associated with higher technical success (87%) compared with wire-based techniques (73%). The Stingray device displayed higher technical success (86%) compared with subintimal tracking and re-entry (STAR) (74%) and limited antegrade subintimal tracking (78%); however, its use has been decreasing, with STAR becoming the most used re-entry technique in 2022 (44% STAR vs 38% Stingray).

CONCLUSIONS

The use of ADR has been decreasing. ADR was used in more complex lesions and was associated with lower technical success and higher major adverse cardiac events compared with non-ADR cases. There has been a decrease in Stingray use and an increase in the use of STAR for re-entry.

Balloon-assisted subintimal entry (BASE) in chronic total occlusion percutaneous coronary interventions

BACKGROUND

There is limited data on the use of the balloon-assisted subintimal entry (BASE) technique in chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

METHODS

We analyzed the baseline clinical and angiographic characteristics and outcomes of 155 CTO PCIs that utilized the BASE technique at 31 US and non-US centers between 2016 and 2023.

RESULTS

The BASE technique was used in 155 (7.9%) of 1968 antegrade dissection and re-entry (ADR) cases performed during the study period. The mean age was 66 ± 10 years, 88.9% of the patients were men, and the prevalence of diabetes (44.6%), hypertension (90.5%), and dyslipidemia (88.7%) was high. Compared with 1813 ADR cases that did not use BASE, the target vessel of the BASE cases was more commonly the RCA and less commonly the LAD. Lesions requiring BASE had longer occlusion length (42 ± 23 vs. 37 ± 23 mm, p = 0.011), higher Japanese CTO (J-CTO) (3.4 ± 1.0 vs. 3.0 ± 1.1, p < 0.001) and PROGRESS-CTO (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention chronic total occlusion) (1.8 ± 1.0 vs. 1.5 ± 1.0, p = 0.008) scores, and were more likely to have proximal cap ambiguity, side branch at the proximal cap, blunt/no stump, moderate to severe calcification, and proximal tortuosity. Technical (71.6% vs. 75.5%, p = 0.334) and procedural success (71.6% vs. 72.8%, p = 0.821), as well as major adverse cardiac events (MACE) (1.3% vs. 4.1%, p = 0.124), were similar in ADR cases that used BASE and those that did not.

CONCLUSIONS

The BASE technique is used in CTOs with longer occlusion length, higher J-CTO score, and more complex angiographic characteristics, and is associated with moderate success but also low MACE.

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.

Clinical effective use of Conquest Pro 12 Sharpened Tip for chronic total occlusion intervention: A series of three case reports

A new chronic total occlusion (CTO) guidewire, Conquest Pro 12 Sharpened Tip (CP12ST), has a stronger penetration force than the original CP12 and a deflection effect that it does not have. The CP12ST enables us to advance into hard plaque that has not ever penetrated, which might change CTO treatment as shown in three cases.

Recanalisation of coronary chronic total occlusions

Percutaneous treatment of coronary chronic total occlusions (CTO) has advanced greatly since its advent in the late 1970s through the development of dedicated wires and microcatheters, the improved skills of highly experienced operators and the adoption of new sophisticated strategies to guide procedural planning. The contemporary procedural success rate is 80-90% with a reduction in complications. Although there has been no improvement in prognosis in randomised trials to date, they, and other controlled registries of thousands of patients, confirm the pivotal role of CTO recanalisation in the treatment of angina and dyspnoea and an improvement in quality of life. Despite this evidence, CTO recanalisation is grossly underutilised. This review reports a detailed overview of the history, indications and treatment strategies for CTO recanalisation and hopes to increase interest among new, and especially young, operators in this demanding, rapidly evolving field of interventional cardiology.

Contemporary Issues in Chronic Total Occlusion Percutaneous Coronary Intervention

Remarkable progress has been achieved in chronic total occlusion (CTO) percutaneous coronary intervention (PCI) in recent years, with refinement of the indications and technical aspects of the procedure, imaging, and complication management. Randomized controlled trials and rigorous prospective registries have provided high-quality data on the benefits and risks of CTO PCI. Global collaboration has led to an agreement on nomenclature, indications, endpoint definition, and principles of clinical trial design that have been distilled in global consensus documents such as the CTO Academic Research Consortium. Increased use of preprocedural coronary computed tomography angiography and intraprocedural intravascular imaging, as well as development of novel techniques and structured CTO crossing and complication management algorithms, allow a systematic, stepwise approach to this difficult lesion subset. This state-of-the-art review provides a comprehensive discussion about the most recent developments in the indications, preprocedural planning, technical aspects, complication management, and future directions of CTO PCI.

[Technical armamentarium for chronic total occlusion of coronary vessels]

Percutaneous revascularization of chronic total occlusion (CTO) of coronary vessels represents a major challenge for contemporary interventional cardiologists. In the last decade there has been an unprecedented effort towards the standardization of revascularization procedures for CTO of coronary vessels. This endeavour has been possible by virtue of the growing interest of various cardiological societies for this patient group. Along with supportive endovascular technologies and percutaneous devices specifically dedicated to this interventional target, the increasing experience of interventionalists enabled continuously growing success for revascularization of CTO of coronary vessels. This review article highlights the currently available tools as well as technologies, techniques and strategies for the percutaneous recanalization of CTO of coronary vessels.

A new combined antegrade and retrograde approach for chronic total occlusion recanalization: Facilitated antegrade fenestration and re-entry

While antegrade techniques remain the cornerstone of chronic total occlusion (CTO) percutaneous coronary intervention (PCI), operators have often to resort to the retrograde approach in complex occlusions. In particular, lesions with proximal cap ambiguity, unclear vessel course and/or poor distal landing zone are difficult to tackle with either antegrade wiring or antegrade dissection and re-entry (ADR), and often require the retrograde approach. After collateral channel crossing, the retrograde approach usually culminates with either reverse controlled antegrade and retrograde subintimal tracking (CART) or retrograde true lumen crossing. Both techniques usually involve the use of an externalization wire, which requires keeping a higher activate clotting time to prevent thrombosis of the retrograde channel and is potentially associated with risk for donor vessel injury. In 2018, we described antegrade fenestration and re-entry (AFR), a targeted ADR technique in which fenestrations between the false and true lumen are created by antegrade balloon dilatation in the extraplaque space at the level of the distal cap, which are subsequently engaged by a polymer-jacketed wire to achieve re-entry. We hypothesized that AFR can also expedite antegrade crossing of the CTO after a wire has reached the distal vessel in a retrograde fashion. In this report, we present two cases in which we successfully achieved antegrade CTO crossing with AFR following retrograde advancement of a guidewire to the distal cap, in new variant of the technique, which we called "facilitated AFR".

Japanese multicenter registry evaluating the antegrade dissection reentry with cardiac computerized tomography for chronic coronary total occlusion

Recently, antegrade dissection re-entry (ADR) with re-entry device for chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has evolved to become one of the pillar techniques of the hybrid algorithm. Although the success rate of the device is high, it could be improved. We sought to evaluate the current trends and issues associated with ADR in Japan and evaluate the potential of cardiac computed tomography angiography (CCTA) for ADR procedure. A total 48 patients with CTO suitable for ADR evaluated by baseline conventional angiography and CCTA were enrolled. Procedural success and technical success were evaluated as the primary and secondary observations. Furthermore, all puncture points were analyzed by CCTA. CT score at each punctured site depended on the location of plaque deposition (none; + 0, at isolated myocardial site; + 1, at epicardial site; + 2) and the presence of calcification (none; + 0, presence; + 1) was analyzed and calculated (score 0–3). Overall procedure success rate was 95.8%. Thirty-two cases were attempted with the ADR procedure and 25 cases of them were successful. The technical success rate was 78.1% and myocardial infarction or other major complications were not observed in any cases. CT score at 60 puncture sites in 32 cases were analyzed and the score at technical success points was significantly smaller compared to that at technical failure points (0.68 ± 1.09 vs 1.77 ± 1.09, p < 0.0001). CTO-PCI with Stingray device in Japan could achieve a high procedure success and technical success rate. Pre procedure cardiac CT evaluation might support ADR procedure for appropriate patient selection or puncture site selection.

Intravascular Ultrasound in Chronic Total Occlusion Percutaneous Coronary Intervention: Solving Ambiguity and Improving Durability

Chronic total occlusions remain among the most technically challenging lesions to treat percutaneously. Limitations of 2-dimensional angiography may further hinder successful treatment of these lesions. Intrasvascular ultrasound has a key role in percutaneous recanalization for a chronic total occlusion by providing key lesion characteristics, facilitating guidewire crossing, elucidating the intraplaque or extralaque path of the guidewire, optimizing lesion preparation, guiding stenting and identifying suboptimal results. Live visualization of the guidewire during crossing may reduce extraplaque wire tracking. This review describes the practical uses of intravascular imaging for commonly encountered scenarios when treating chronic total occlusions.

Knuckle wire technique in percutaneous coronary intervention of chronic total occlusion: Knuckle wire technique

In percutaneous coronary intervention, the knuckle wire technique is one of the approaches to cross the long and ambiguous course of the occluded segment. However, this technique is generally used as a last alternative, when all other techniques fail. Although knuckle wiring expedites chronic total occlusion crossing, it can also complicate the percutaneous coronary intervention strategy irreversibly. Therefore, understanding the various aspects of the knuckle wire technique is a prerequisite in a chronic total occlusion setting. The authors herein intend to describe in detail the knuckle wire technique and its safe and effective approach in various chronic total occlusion wiring strategies, while befitting to the scope of a mainstream interventionist.

Impact of adherence to the hybrid algorithm for initial crossing strategy selection in chronic total occlusion percutaneous coronary intervention

INTRODUCTION AND OBJECTIVES

The hybrid algorithm was designed to assist with initial and subsequent crossing strategy selection in chronic total occlusion (CTO) percutaneous coronary interventions (PCIs). However, the success of the initially selected strategy has received limited study.

METHODS

We examined the impact of adherence to the hybrid algorithm recommendation for initial CTO crossing technique selection in 4178 CTO PCIs from a large multicenter registry.

RESULTS

The initial crossing strategy was concordant with the hybrid algorithm recommendation in 1833 interventions (44%). Patients in the concordant group had a similar age to those in the discordant group but a lower mean J-CTO score (2.0 ± 1.4 vs 2.8 ± 1.1; P < .01). The concordant group showed higher technical success with the first crossing strategy (68% vs 48%; P < .01) and higher overall technical success (88% vs 83%; P < .01) with no difference in the incidence of in-hospital major adverse events (1.8% vs 2.3%; P = .26). In multivariable analysis, after adjustment for age, prior myocardial infarction, prior PCI, prior coronary artery bypass grafting, J-CTO score, and scheduled CTO PCI, nonadherence to the hybrid algorithm was independently associated with lower technical success of the initial crossing strategy (odds ratio, 0.55; 95% confidence interval, 0.48-0.64; P < .01).

CONCLUSIONS

Adherence to the hybrid algorithm for initial crossing strategy selection is associated with higher CTO PCI success but similar in-hospital major adverse cardiac events.

Advances in percutaneous coronary intervention for chronic total occlusions: current antegrade dissection and reentry techniques and updated algorithm

Percutaneous coronary intervention (PCI) for chronic total occlusions (CTO) is considered relatively complex with low success rates and high complication rates. Treating a CTO with PCI using the hybrid algorithm increases success rates with acceptable complication rates. An essential part of the hybrid algorithm is antegrade dissection and reentry (ADR). In PCI of a non-CTO coronary lesion, the guidewire over which the stent is advanced and placed stays within the true lumen of the coronary artery. ADR techniques make it possible to cross the lesion through the wall of the coronary artery, the subintimal space, thus creating a small bypass within the architecture of the coronary artery and restoring antegrade blood flow. ADR increases success rates, especially in more difficult CTO procedures. In the last decade, new materials and techniques have been introduced in quick succession, which are summarised in this review. Consequently an updated ADR algorithm is presented, which can support the CTO operator during an ADR procedure.

Derivation and validation of the J-CTO extension score for pre-procedural prediction of major adverse cardiac and cerebrovascular events in patients with chronic total occlusions

We developed a prediction model of long-term risk after percutaneous coronary intervention (PCI) for coronary chronic total occlusion (CTO) based on pre-procedural clinical information. A total of 4,139 eligible patients, who underwent CTO-PCI at 52 Japanese centers were included. Specifically, 1,909 patients with 1-year data were randomly divided into the derivation (n = 1,273) and validation (n = 636) groups. Major adverse cardiac and cardiovascular event (MACCE) was the primary endpoint, including death, stroke, revascularization, and non-fatal myocardial infarction. We assessed the performance of our model using the area under the receiver operating characteristic curve (AUC) and assigned a simplified point-scoring system. One-hundred-thirty-eight (10.8%) patients experienced MACCE in the derivation cohort with hemodialysis (HD: odds ratio [OR] = 2.55), left ventricular ejection fractions (LVEF) <35% (OR = 2.23), in-stent occlusions (ISO: OR = 2.27), and diabetes mellitus (DM: OR = 1.72). The AUC of the derivation model was 0.650. The model’s performance was similar in the validation cohort (AUC, 0.610). When assigned a point for each associated factor (HD = 3, LVEF <35%, ISO = 2, and DM = 1 point), the average predicted versus the observed MACCE probability using the Japan-CTO extension score for the low, moderate, high, and very high risk groups was 8.1% vs. 7.3%, 16.9% vs. 15.9%, 22.0% vs. 26.1%, and 56.2% vs. 44.4%, respectively. This novel risk model may allow for the estimation of long-term risk and be useful in disseminating appropriate revascularization procedures.

Procedural outcomes of chronic total occlusion percutaneous coronary intervention in patients with dissection and reentry versus wire escalation techniques: a meta-analysis

BACKGROUND

The procedural safety of dissection and reentry (DR) techniques in chronic total occlusion (CTO) percutaneous coronary intervention (PCI) remains controversial, when compared with conventional wire escalation (WE) techniques. The meta-analysis was performed to evaluate the impact of DR techniques vs. WE techniques on periprocedural outcomes in patients with CTO undergoing PCI.

METHODS

Studies were searched in electronic database from inception to December 2018. Results were pooled using random effects model and fixed effects model.

RESULTS

The pooled analyses revealed that DR techniques increased risks of periprocedural complications in patients with CTO PCI, including higher coronary perforation rate [risk ratio (RR) = 2.10, 95% confidence interval (CI) 1.24-3.55], periprocedural myocardial infarction (RR = 1.85, 95% CI 1.23-2.78), branch occlusion (RR = 2.69; 95% CI 1.92-3.77) and coronary hematoma (RR = 3.06; 95% CI 2.45-3.82) detected by intravascular ultrasound, when compared to those with WE techniques. However, DR techniques were more applied in patients with higher complexity CTO lesions, which was evidenced by higher J-CTO score [standard mean differences (SMD) = 0.71, 95% CI 0.51-0.91] and longer fluoroscopy time (SMD = 0.93, 95% CI 0.70-1.16), that may explain the higher complications rates in the DR techniques group as compared with WE techniques.

CONCLUSION

The present meta-analysis suggests that the DR technique is relatively frequently used during contemporary CTO PCI, especially for challenging more complex CTO lesions. However, it is associated with higher, yet acceptable, rates of periprocedural adverse events as compared with a conventional WE strategy. Further refinement of DR techniques and evidence from large RCTs is needed to define the optimal role of DR in hybrid CTO PCI.

In-hospital outcomes of chronic total occlusion percutaneous coronary intervention in patients with and without prior coronary artery bypass graft: A protocol for systematic review and meta analysis

The clinical outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) in prior coronary artery bypass graft (pCABG) patients have been investigated; however, the results are inconsistent.The present meta-analysis compared the clinical outcomes of CTO PCI in patients with and without prior CABG (nCABG). The endpoints included technical success, procedural success, all-cause mortality, myocardial infarction (MI), major bleeding, coronary perforation, pericardial tamponade, emergency CABG, and vascular access complication.A total of 7 studies comprising of 11099 patients were included in this meta-analysis. The results showed that compared to nCABG patents, pCABG patients were associated with lower technical success (82.3% versus 87.8%; OR, 0.60; 95% CI, 0.53-0.68; P < .00001; I = 0%) and procedural success (80.4% versus 86.2%; OR, 0.61; 95% CI, 0.53-0.70; P < .00001; I = 10%); a higher risk of all-cause mortality (OR, 2.95; 95% CI, 1.56-5.57; P = 0.0008; I = 0%), MI (OR, 2.30; 95% CI, 1.40-3.80; P = .001; I = 5%), and coronary perforation (OR, 2.16; 95% CI, 1.51-3.08; P < 0.0001; I = 52%). On the other hand, the risk of pericardial tamponade (OR, 0.42; 95% CI, 0.15-1.18; P = .10; I = 21%), major bleeding (OR, 1.51; 95% CI, 0.90-2.53; P = .11; I = 0%), vascular access complication (OR, 1.50; 95% CI, 0.93-2.41; P = .10; I = 0%), and emergency CABG (OR, 0.99; 95% CI, 0.25-3.91; P = .99; I = 0%) was similar in both groups.Compared to nCABG patients, pCABG patients had lower CTO PCI success rates, higher rates of in-hospital mortality, MI, and coronary perforation, and similar risk of pericardial tamponade and vascular complication rates.

Factors associated with antegrade true-sub-true phenomenon in percutaneous coronary intervention for chronic total occlusion

Background

Recently, the importance of chronic total occlusion (CTO)-percutaneous coronary intervention (PCI) has been emphasized with greater success rates. In the antegrade wire based approach, it is generally considered that the guidewire would not advance from the subintimal space to the intimal space without dissection re-entry device. However, it is sometimes observed by intravascular ultrasound (IVUS) that the guidewire within the subintimal space advanced into the distal true lumen. The purpose of this study was to investigate specific conditions or characteristics which were associated with “antegrade true-sub-true” phenomenon in CTO-PCI.

Methods

We retrospectively reviewed consecutive 320 CTO lesions that underwent CTO-PCI in our institution. Among them, 16 lesions in which the IVUS confirmed the “antegrade true-sub-true” phenomenon were categorized as the true-sub-true group, whereas 27 lesions that resulted in unsuccessful CTO-PCI were categorized as the unsuccessful group. We compared the clinical, lesion, and procedural characteristics between the true-sub-true group and the unsuccessful group.

Results

The prevalence of bifurcation with abrupt type in CTO exit-sites was significantly higher in the true-sub-true group in comparison to the unsuccessful group (75.0% vs. 25.9%, p = 0.002). The multivariate logistic regression analysis revealed that bifurcation with abrupt type in CTO exit-site (OR 8.017; 95%CI: 1.484–43.304; p = 0.016) was independent predictor of the antegrade true-sub-true phenomenon.

Conclusions

In CTO-PCI, the antegrade true-sub-true phenomenon is rare, but can be a last chance for successful PCI. Bifurcation with abrupt type in CTO exit-site was significantly associated with the antegrade true-sub-true phenomenon.

Multicenter experience with the antegrade fenestration and reentry technique for chronic total occlusion recanalization

OBJECTIVES

We aimed to evaluate the efficacy and safety of antegrade fenestration and reentry (AFR) for chronic total occlusion (CTO) recanalization in a multicenter registry.

BACKGROUND

Adoption of antegrade dissection/reentry (ADR) for CTO recanalization has been limited, and novel ADR techniques are needed.

METHODS

AFR involves the balloon-induced creation of multiple fenestrations between the false and true lumen. A targeted true lumen reentry is subsequently achieved with a low tip-load polymer-jacketed guidewire. Following the initial description and dissemination of AFR, patients undergoing AFR-based CTO recanalization at nine centers were included in the present registry. Study endpoints were AFR success, procedural success, and target-lesion failure (TLF) on follow-up.

RESULTS

We included 41 patients. Mean J-CTO score was 2.5 ± 1.4. In 80.5% of cases, AFR was performed after failed antegrade wire escalation. Another ADR technique was used before AFR in one-third of cases. AFR achieved distal true lumen reentry in n = 27/41 (65.9%) cases. In n = 14/41 (34.1%) cases with AFR failure, use of alternative techniques led to successful CTO recanalization in eight additional patients. The overall technical and procedural success rates were 85.4% and 82.9%, respectively. No AFR-related complications were observed. One-year TLF rate was 8.3% overall, with no differences between successful and failed AFR.

CONCLUSIONS

We report on AFR feasibility in a multicenter registry of patients undergoing CTO recanalization. We observed a moderate success rate, coupled with the absence of complications. Moreover, even a failed AFR attempt did not preclude the use of alternative techniques to achieve recanalization. Further studies should confirm and extend our findings.

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.

Temporal Trends in Chronic Total Occlusion Interventions in Europe

BACKGROUND

The study focuses on the evolution of practice, procedural outcomes, and in-hospital complications of chronic total occlusion percutaneous coronary intervention in Europe.

METHODS AND RESULTS

Data from 17 626 procedures enrolled in European Registry of Chronic Total Occlusion between January 2008 and June 2015 were assessed. The mean patient age was 63.9±10.9 years; 85% were men. Procedural success increased from 79.7% to 89.3% through the study period. Patients enrolled during the years had increasing comorbidities and lesion complexity (J-CTO score [Multicenter CTO Registry of Japan] increased from 1.76±1.03 in 2008 to 2.17±0.91 in 2015; P for trend, <0.001). Retrograde approach utilization steadily increased from 10.1% in 2008 to 29.9% in 2015 ( P for trend, <0.001). Antegrade dissection reentry adoption was low, not exceeding 5.5%. In-hospital mortality decreased during the study period from 0.4% to 0.1% ( P for trend, <0.001), whereas in-hospital complication rates remained essentially unchanged, in the range 4.4% to 5.2% ( P for trend, 0.390).

CONCLUSIONS

Chronic total occlusion percutaneous coronary intervention has shown a steady increase in procedural success rate over time, with unchanged complication rates, despite the increasing complexity of the lesions attempted. The J-CTO score predictive value for procedural success was low for the entire registry and had no predictive ability for the retrograde approach.

Modified subintimal transcatheter withdrawal: A novel technique for hematoma decompression to facilitate distal reentry during coronary chronic total occlusion recanalization

A controlled antegrade dissection and reentry technique is the most commonly employed crossing strategy for long coronary chronic total occlusions. The development of compressive hematoma is a recognized complication and results in the impairment of distal vessel visualization and hinders successful reentry attempts. We describe a novel technique utilizing a widely available microcatheter to decompress the subintimal hematoma to restore distal visualization and allow successful reentry.

Subintimal Versus Intraplaque Recanalization of Coronary Chronic Total Occlusions: Mid-Term Angiographic and OCT Findings From the ISAR-OCT-CTO Registry

OBJECTIVES

The aim of this study was to compare angiographic and optical coherence tomography findings following subintimal as opposed to intraplaque recanalization of chronic total occlusions (CTOs).

BACKGROUND

There is ongoing controversy regarding outcomes of intraplaque versus subintimal CTO recanalization.

METHODS

Consecutive patients undergoing angiography and intravascular optical coherence tomography following CTO recanalization were included in the ISAR-OCT-CTO (Intracoronary Stenting and Angiographic Results - Optical Coherence Tomography for Chronic Total Occlusions) registry. The study endpoints were percent diameter stenosis and late lumen loss as well as rate of uncovered and malapposed struts. Independent correlates of uncovered and malapposed struts were assessed by multivariate analysis.

RESULTS

The study included 75 patients. Intraplaque and dissection and re-entry techniques (DART) were used in 46 and 29 patients, respectively. There were no differences in terms of in-segment percent diameter stenosis (median 36.9 [interquartile range (IQR): 26.4 to 43.1] vs. 31.2 [IQR: 23.2 to 49.5]; p = 0.656), in-stent late lumen loss (0.215 mm [IQR: 0.063 to 0.495 mm] vs. 0.230 mm [IQR: 0.060 to 0.645 mm]; p = 0.837), or in-segment late lumen loss (0.030 mm [IQR: -0.278 to 0.510 mm] vs. 0.130 mm [IQR: -0.120 to 0.500 mm]; p = 0.395) at follow-up between the 2 techniques. Optical coherence tomography analysis showed comparable strut coverage (79.9% vs. 71.3%; p = 0.255) but significantly higher strut malapposition (6.6% vs. 13.6%; p < 0.001) following DART. Use of DART independently correlated with presence of strut malapposition (odds ratio: 3.41; 95% confidence interval: 1.24 to 9.36; p = 0.017) but not of strut coverage (odds ratio: 0.65; 95% confidence interval: 0.28 to 1.49; p = 0.314).

CONCLUSIONS

Intraplaque and subintimal recanalization techniques are associated with comparable mid-term angiographic results. Although the rate of uncovered struts is high following CTO recanalization, the recanalization technique does not independently correlate with presence of uncovered struts. There is a high rate of strut malapposition following CTO recanalization, particularly if achieved by means of DART.

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.

A Technical Focus on Antegrade Dissection and Re-entry for Coronary Chronic Total Occlusions: a Practice Update for 2019

Coronary chronic total occlusions (CTOs) are a commonly encountered lesion. These present in a diverse patient population with variable anatomy. Technical success rates of ~90% are achievable for CTO lesions in centers with appropriate expertise. Many lesions can be crossed with wire-based techniques. However, the most anatomically complex and technically challenging lesions will often require more advanced approaches such as retrograde access and/or the application of blunt dissection techniques in the vessel to safely navigate long and/or ambiguous CTO segments. Retrograde dissection and re-entry (RDR) and antegrade dissection and re-entry (ADR) strategies are often needed to treat such lesions. In many circumstances, ADR offers a safe and efficient means to successfully cross a CTO lesion. Therefore, operators must remain cognizant of the risks and benefits of differing technical approaches during CTO percutaneous coronary intervention, particularly when both ADR and RDR are feasible. This article provides an overview of the ADR technique in addition to updated approaches in contemporary clinical practice.

An algorithmic approach for the management of ostial right coronary artery chronic total occlusions

Treatment of ostial chronic total occlusions (CTOs) of the right coronary artery (RCA) can be challenging. We present an algorithmic approach to the management of such lesions that incorporates all contemporary equipment and techniques. If the RCA ostium can be engaged with a guide catheter then antegrade crossing attempts should be performed. If the antegrade guidewire enters the subintimal space, re-entry into the distal true lumen is performed provided that the antegrade guide catheter provides enough support. If re-entry cannot be achieved, the antegrade wire is left in place to facilitate retrograde recanalization attempts (usually performed using the reverse controlled antegrade and retrograde tracking and dissection-reverse CART-technique). If the RCA ostium cannot be engaged with a guide catheter (for example in flush ostial occlusions) or if the guide catheter does not provide sufficient support, a primary retrograde approach is required, aiming for retrograde guidewire puncture into the aorta, followed by snaring and externalization. Retrograde guidewire puncture can be challenging, requiring use of stiff, highly penetrating guidewires or occasionally use of the Carlino technique. The aforementioned algorithm can facilitate crossing of ostial RCA CTOs.

The "double stingray technique" for recanalizing chronic total occlusions with bifurcation at the distal cap

Antegrade dissection re-entry is often discouraged for chronic total occlusions (CTOs) with a bifurcation at the distal cap due to risk of side branch occlusion that can lead to periprocedural myocardial infarction and incomplete revascularization. Antegrade dissection re-entry, however, is often needed, especially in complex cases. We present the novel "double Stingray technique" for CTOs involving bifurcations, in which the Stingray system is used twice for re-entry into both vessel branches, followed by two-stent bifurcation stenting to maintain the patency of both branches.

Antegrade fenestration and re-entry: A new controlled subintimal technique for chronic total occlusion recanalization

OBJECTIVES

To describe and evaluate the efficacy of a novel antegrade dissection/re-entry (ADR) technique, called antegrade fenestration and re-entry (AFR), for chronic total occlusions (CTO) percutaneous coronary intervention (PCI).

BACKGROUND

The widespread adoption of ADR is limited by several technical, logistic, and financial factors. Therefore, novel ADR techniques are needed.

METHODS

AFR consists in creating multiple fenestrations of the dissection flap separating the false and true lumen. This is achieved by advancing a balloon (sized 1:1 with the artery diameter) onto the antegrade wire into the subintimal space, and inflating it at the level of the distal cap. A soft polymer-jacketed guidewire is then advanced across the fenestrations created by balloon inflation from the subintimal space into the true lumen. Following its theoretical formulation, patients undergoing ADR-based CTO recanalization at our institution were considered for AFR treatment.

RESULTS

Between November 2015 and October 2017, 279 CTO PCIs were performed. Of those, ADR was utilized in 33 (12%) cases, of whom AFR was used in 6 (18%). In all but one cases, AFR was performed after failed true-to-true lumen crossing, while in the remainder it was utilized after extensive subintimal space disruption following alternative ADR techniques. AFR was successful in all six cases and no complications were observed.

CONCLUSIONS

We have developed a novel ADR technique which aims at complementing the CTO operator's armamentarium. AFR does not preclude alternative bailout techniques, and is inexpensive and easy to perform. A dedicated study should confirm our findings in a large cohort.