Overview and proposed terminology for the reverse controlled antegrade and retrograde tracking (reverse CART) techniques

Retrograde Coronary Chronic Total Occlusion Intervention (JR-CTO) Score: From the Japanese CTO-PCI Expert Registry

BACKGROUND

Despite the effectiveness of the retrograde approach for chronic total occlusion (CTO) lesions, there are no standardized tools to predict the success of retrograde percutaneous coronary intervention (PCI).

OBJECTIVES

The aim of this study was to develop a prediction tool to identify CTO lesions that will achieve successful retrograde PCI.

METHODS

This study evaluated data from 2,374 patients who underwent primary retrograde CTO-PCI and were enrolled in the Japanese CTO-PCI Expert Registry between January 2016 and December 2022 (NCT01889459). All observations were randomly assigned to the derivation and validation cohorts at a 2:1 ratio. The prediction score for guidewire failure in retrograde CTO-PCI was determined by assigning 1 point for each factor and summing all accrued points.

RESULTS

The JR-CTO score (moderate-severe calcification, tortuosity, Werner collateral connection grade ≤1, and nonseptal collateral channel) demonstrated a C-statistic for guidewire failure of 0.72 (95% CI: 0.67-0.76) and 0.71 (95% CI: 0.64-0.77) in the derivation and validation cohorts, respectively. Patients with lower scores had higher guidewire and technical success rates and decreased guidewire crossing time and procedural time (P < 0.01).

CONCLUSIONS

The JR-CTO (Japanese Retrograde Chronic Total Occlusion) score, a simple 4-item score that predicts successful guidewire crossing in patients undergoing retrograde CTO-PCI, has the potential to support clinical decision-making for the retrograde approach.

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.

"Catheter Kissing" Technique to Recanalize Chronic Total Occlusions in Iliac Artery with Wire-Catheter Approach

BACKGROUND

To describe a technique in which 2 5-F curved catheters were used to facilitate the wire-catheter approach for recanalizing chronic total occlusions (CTOs) in the iliac arteries concurrently affecting the common iliac artery and external iliac artery.

METHODS

This was a single-center retrospective analysis involving endovascular recanalization of 17 iliac artery CTOs in 15 patients (mean age: 73.66 years; all men) between January 2019 and October 2022 using the subintimal arterial flossing with antegrade-retrograde intervention technique. With antegrade and retrograde guidewires in the subintimal spaces of CTOs, the location where the 2 guidewires seemed to overlap was identified as the rendezvous point. Although the 2 guidewires appeared to be in close proximity, there was no evidence that the bidirectional subintimal channels were connected. If several initial attempts failed, 2 5-F multipurpose catheters were introduced to the rendezvous point, followed by twisting, pulling, and pushing maneuvers until the tips of the catheters touched, indicating that the bidirectional subintimal channels were joined. A second wire rendezvous attempt was then employed to create a flossing-type guidewire. Outcome measurements included technical success, rendezvous points, complications, and procedure duration.

RESULTS

Among this cohort, 80.0% smoked and 66.7% had hypertension. In 11 limbs (64.7%), when initial wire rendezvous attempts failed, the "catheter kissing" technique was employed to successfully recanalize iliac artery CTOs, taking an average of 3.80 ± 1.64 min to complete the secondary wire rendezvous. The average length of CTOs was 111.06 ± 9.99 mm, with 7 (41.2%) and 8 (47.1%) cases exhibiting severe calcification and flush occlusion, respectively. The wire rendezvous point for all cases was in external iliac artery and the average time for successful secondary wire rendezvous was 3.80 ± 1.64 min. All patients were treated with iliac artery stents. No statistically significant difference was observed between the puncture sites of the common femoral artery and superficial femoral artery in relation to failure of the primary wire rendezvous (P = 0.644). No in-hospital deaths or complications were associated with the procedure, including iliac artery rupture, distal embolization, or access site complications.

CONCLUSIONS

In patients with extensive iliac artery CTOs, the "catheter kissing" technique may offer an effective and time-efficient recanalization approach, without requiring additional specialized devices. Importantly, the risk of complications remains unchanged even when employing a wire rendezvous in a challenging subintimal space.

The Retrograde Approach to Chronic Total Occlusion Percutaneous Coronary Interventions: Technical Analysis and Procedural Outcomes

BACKGROUND

Retrograde chronic total occlusion (CTO) percutaneous coronary intervention (PCI) is associated with lower success and higher complication rates when compared with the antegrade approach.

OBJECTIVES

This study sought to assess contemporary techniques and outcomes of retrograde CTO PCI.

METHODS

We examined the baseline characteristics, procedural techniques and outcomes of 4,058 retrograde CTO PCIs performed at 44 centers between 2012 and 2023. Major adverse cardiac events (MACE) included any of the following in-hospital events: death, myocardial infarction, repeat target vessel revascularization, pericardiocentesis, cardiac surgery, and stroke.

RESULTS

The average J-CTO (Multicenter CTO Registry in Japan) score was 3.1 ± 1.1. Retrograde crossing was successful in 60.5% and lesion crossing in 81.6% of cases. The collaterals pathways successfully used were septals in 62.0%, saphenous vein grafts in 17.4%, and epicardials in 19.1%. The technical and procedural success rates were 78.7% and 76.6%, respectively. When retrograde crossing failed, technical success was achieved in 50.3% of cases using the antegrade approach. In-hospital MACE was 3.5%. The clinical coronary perforation rate was 5.8%. The incidence of in-hospital MACE with retrograde true lumen crossing, just marker antegrade crossing, conventional reverse controlled antegrade and retrograde tracking (CART), contemporary reverse CART, extended reverse CART, guide-extension reverse CART, and CART was 2.1%, 0.8%, 5.5%, 3.0%, 2.1%, 3.2%, and 4.1%, respectively; P = 0.01).

CONCLUSIONS

Retrograde CTO PCI is utilized in highly complex cases and yields moderate success rates with 5.8% perforation and 3.5% periprocedural MACE rates. Among retrograde crossing strategies, retrograde true lumen puncture was the safest. There is need for improvement of the efficacy and safety of retrograde CTO PCI.

A case report on intravascular lithotripsy to facilitate retrograde wire passage from the subintimal to the luminal space in a calcified chronic total occlusion

Background

Severe calcifications are a major reason for failures in chronic total coronary occlusions, as they can obstruct the wire passage both in the antegrade and retrograde technique.

Case summary

The proximal occlusion of the left anterior descending artery in a 75-year-old man presented with a completely concentric calcified ring all along the segment proximal to the occlusion. The antegrade wire could not pass the calcified occlusion, and in a retrograde approach via the right posterior descending artery the retrograde wire was not able to enter the lumen from a subintimal position outside of the calcified ring. Intravascular lithoplasty in the proximal segment led to a crack in this ring to enable the same retrograde wire now to pass into the true lumen with then successful conclusion of the case. Intravascular ultrasound demonstrated the modification of the calcified ring and the passage of the wire with only a very short subintimal pathway.

Discussion

Intravascular lithoplasty is a new option to modify severely calcified vessel segments to facilitate the reverse controlled antegrade and retrograde tracking approach. In the present case, this helped to avoid a long subintimal pathway and preserved the vessel anatomy.

The role of intravascular imaging in chronic total occlusion percutaneous coronary intervention

Chronic total occlusions (CTOs) represent the most complex subset of coronary artery disease and therefore careful planning of CTO percutaneous coronary recanalization (PCI) strategy is of paramount importance aiming to achieve procedural success, and improve patient's safety and post CTO PCI outcomes. Intravascular imaging has an essential role in facilitating CTO PCΙ. First, intravascular ultrasound (IVUS), due to its higher penetration depth compared to optical coherence tomography (OCT), and the additional capacity of real-time imaging without need for contrast injection is considered the preferred imaging modality for CTO PCI. Secondly, IVUS can be used to resolve proximal cap ambiguity, facilitate wire re-entry when dissection and re-entry strategies are applied and most importantly to guide stent deployment and optimization post implantation. The role of OCT during CTO PCI is currently limited to stent sizing and optimization, however, due to its high spatial resolution, OCT is ideal for detecting stent edge dissections and strut malapposition. In this review, we describe the use of intravascular imaging for lesion crossing, plaque characterization and wire tracking, extra- or intra-plaque, and stent sizing and optimization during CTO PCI and summarize the findings of the major studies in this field.

CTO and Bifurcation Lesions: An Expert Consensus From the European Bifurcation Club and EuroCTO Club

Knowledge in the field of bifurcation lesions and chronic total occlusions (CTOs) has progressively improved over the past 20 years. Therefore, the European Bifurcation Club and the EuroCTO Club have decided to write a joint consensus statement to share general knowledge and practical approaches in this complex field. When percutaneously treating CTOs, bifurcation lesions with relevant side branches (SBs) are found in approximately one-third of cases (35% at the proximal cap, 38% at the distal cap, and 27% within the CTO body). Occlusion of a relevant SB is not rare and has been shown to be associated with procedural complications and adverse outcomes. Simple bifurcation rules are very useful to prevent SB occlusion, and provisional SB stenting is the recommended approach in the majority of cases: protect the SB as soon as possible by wiring it, respect the fractal anatomy of the bifurcation by using the 3-diameter rule, and avoid using dissection and re-entry techniques. A systematic 2-stent approach can be used if needed or sometimes to connect both branches of the bifurcation. The retrograde approach can be very useful to save a relevant SB, especially in the case of a bifurcation at the distal cap or within the CTO body. Intravascular ultrasound is also a very important tool to address the difficulties with bifurcations at the proximal or distal cap and sometimes also within the CTO segment. Double-lumen microcatheters and angulated microcatheters are crucial tools to resolve access difficulties to the SB or the main branch.

A Novel Parallel Wire-based Antegrade Dissection Re-entry Technique for Failed Retrograde Attempt of Coronary Chronic Total Occlusions with Risk Nomogram Analysis

BACKGROUND

Rapid development in coronary chronic total occlusion (CTO) interventional techniques and devices have achieved a greater success rate with favorable outcomes. Antegrade dissection re-entry (ADR) technique is an important CTO crossing strategy and a desirable approach for long CTOs with good distal landing zone. However, unsuccessful procedures in contemporary CTO-percutaneous coronary intervention (PCI) remain, especially in lesions with non-interventional collaterals.

METHOD

Based on a single center experience, a hybrid interventional algorithm, parallel wire-based ADR (PW-ADR) combines the advantages of parallel wire technique (PWT) and device-based ADR to target CTO lesions with failed retrograde approach. A retrospective analysis of patients who underwent PW-ADR was performed. A risk nomogram was created to identify patients at high risk for technical failure.

RESULTS

A total of 57 patients treated with PW-ADR were ultimately included in the present study. A total of 46 (80.7%) cases achieved technical success and procedural success, with low incidence of in-hospital complications or 1-year major adverse cardiac events (MACE). The risk nomogram identified 3 predictor variables associated with technical failure of PW-ADR, including tortuous vessel, J-CTO score, and times of antegrade coronary angiography (CAG) during ADR, with promising accuracy (AUROC 0.947).

CONCLUSION

The novel hybrid CTO-PCI algorithm, PW-ADR, provided an alternative interventional approach for complex CTO lesions with a promising success rate. The risk nomogram served as a prompter for high-risk cases, which may warrant a change in treatment strategy.

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.

Retrograde CTO-PCI Using an Internal Thoracic Bypass Graft Segment in a Patient with Acute Inferior ST-Elevation Myocardial Infarction and Cardiogenic Shock

Background

Percutaneous coronary intervention (PCI) of the “culprit” artery is the recommended mechanical reperfusion strategy in the setting of ST-segment elevation myocardial infarction (STEMI). As PCI of bypass grafts may be associated with higher risks and lower procedural success rates, in patients with a history of previous coronary artery surgery, PCI directed at revascularization of the native vessels should be considered, but this may be difficult in the setting of a chronically occluded artery.

Case Presentation

A patient with a history of multivessel coronary artery disease and a chronic total occlusion (CTO) of the right coronary artery (RCA) requiring arterial bypass surgery, presented with an acute inferior STEMI and cardiogenic shock. It was felt that shock was caused by the acute thrombotic occlusion of a right internal thoracic artery (RITA) bypass graft that had been sequentially anastomosed to the left circumflex (LCx) and right coronary arteries. Despite initiation of extracorporeal membrane oxygenation (ECMO), the patient remained in refractory shock and acute revascularization of the right coronary artery was performed through the RITA bypass segment using antegrade access to the graft through the LCx and then a retrograde approach to open a CTO of the RCA. After successful revascularization, the patient was successfully weaned from ECMO. Over 12 months of follow-up, the patient did well and was documented to have improved left ventricular systolic function.

Conclusion

This report is the first to document the successful use of a retrograde approach through an arterial graft segment to revascularize a chronic total occlusion in the setting of acute STEMI and cardiogenic shock.

Successful Endovascular Therapy for Total Occlusion of the Distal Radial and Ulnar Artery with Palmar Artery Lesion in a Patient with Critical Hand Ischemia Associated with Systemic Sclerosis

Vasculopathy of systemic sclerosis (SSc) is known to lead to severe limb ischemia and is often associated with macrovascular diseases. Revascularization of proximal macrovascular lesions that cause limb ischemia in patients with SSc has been recommended; however, it has rarely been reported for lesions below-the-elbow (BTE) involving the palmar artery. A 66-year-old female patient with SSc experienced critical hand ischemia (CHI) with gangrene of the left third finger that failed to respond to conventional pharmacological treatment. Angiography revealed total occlusion of the distal radial and ulnar arteries with a palmar artery lesion. Balloon angioplasty was performed for bilateral occlusive lesions around the wrist, which improved antegrade flow to the digital artery. Endovascular therapy may be a feasible option for BTE lesions involving palmar artery disease, presenting with CHI in SSc, when conventional conservative treatments fail.

Use your head: overcoming epicardial complications during a single-catheter chronic total occlusion-a case-based review

The success of attempts at opening chronic total occlusions (CTO) has dramatically increased in recent times due to the development of new techniques such as the use of the retrograde approach through epicardial collaterals. However, this approach admittedly brings with it an increased risk, and this must be balanced against the potential benefits. We present the case of a 61-year-old gentleman with Canadian Cardiovascular Society (CCS) Class III angina with a background history of hypertension and dyslipidaemia, who was an ex-smoker, and whose diagnostic coronary angiogram revealed CTOs of both the right and left circumflex coronary arteries. Following a heart team discussion, a percutaneous approach to treatment by staged approach was favoured, with the first stage being opening of the CTO of the right coronary artery. A retrograde approach with the use of a Corsair microcatheter facilitated reverse CART (controlled antegrade and retrograde tracking). Unfortunately, upon removal of the Corsair, a rupture of the epicardial collateral was noted with profuse bleeding into the pericardial space. This was treated successfully with a BeGraft-covered stent to obtain proximal control, and a Cooke Tornado neuro-interventional coil to obtain distal control, delivered antegrade through the now recanalized RCA. This case-based review then highlights several unique learning points, in particular to understand, in general terms, the approach to CTO; to understand the potential complications associated with a retrograde epicardial collateral approach; to understand the stepwise approach to dealing with perforation; and, finally, to understand how an occlusion coil works.

Advances in the Post-coronary Artery Bypass Graft Management of Occlusive Coronary Artery Disease

Revascularisation of chronic total occlusion (CTO) represents one of the most challenging aspects of percutaneous coronary intervention, but advances in equipment and an understanding of CTO revascularisation techniques have resulted in considerable improvements in success rates. In patients with prior coronary artery bypass grafting (CABG) surgery, additional challenges are encountered. This article specifically explores these challenges, as well as antegrade methods of CTO crossing. Techniques, equipment that can be used and reference texts are highlighted with the aim of providing potential CTO operators adequate information to tackle additional complexities likely to be encountered in this cohort of patients. This review forms part of a wider series where additional aspects of patients with prior CABG should be factored into decisions and methods of revascularisation.

Outcomes of contemporary versus conventional reverse controlled and antegrade and retrograde subintimal tracking in chronic total occlusion revascularization

BACKGROUND

Chronic total occlusion (CTO) lesions remain technically challenging for percutaneous coronary intervention (PCI). The introduction of a retrograde approach has allowed marked improvement in the success rate of CTO recanalization. Reverse controlled anterograde and retrograde sub-intimal tracking (reverse CART) is the predominant retrograde wire crossing technique and can be broadly classified into three categories: (1) conventional (2) contemporary and (3) extended. The present study aimed to compare the safety and efficacy of conventional and contemporary reverse CART techniques.

METHODS

From March 2015 to May 2020, 303 patients achieving successful retrograde guidewire crossing with conventional or contemporary reverse CART during CTO PCI were included in the study. The patient characteristics, procedural outcomes and in-hospital and 1-year clinical events were compared between the conventional and contemporary groups.

RESULTS

The distributions of the baseline and angiographic characteristics were similar in both study arms, except the CTO lesions of the conventional group were more complex, as reflected by borderline significantly higher mean J-CTO scores (3.4 ± 0.7 vs. 3.3 ± 0.8; p = 0.059). Recanalization using contemporary reverse CART was associated with a short procedure time (189.8 ± 44.4 vs. 181.7 ± 37.3 min; p = 0.044) and decreased procedural complications, particularly target vessel perforation (3.6% vs. 0.6%; p = 0.063) and major side-branch occlusion (36.7% vs. 28.0%; p = 0.051). Technical and procedural success and the in-hospital and 1-year outcomes were not significantly different between the groups.

CONCLUSIONS

Contemporary reverse CART is associated with favorably high efficiency and low-complication rates and carries a comparable success rate and 1-year clinical outcomes as conventional reverse CART.

Outcomes of retrograde approach for chronic total occlusions by guidewire location

BACKGROUND

Connecting the antegrade wire (AW) and the retrograde wire (RW) is a goal of chronic total occlusion (CTO) treatment, but angiographic guidewire location is sometimes misleading.

AIMS

The aim of this study was to evaluate the association between intravascular ultrasound (IVUS)-defined AW and RW position and procedural outcomes when treating CTO lesions using the retrograde approach.

METHODS

Overall, 191 CTO lesions treated using an IVUS-guided retrograde approach at three centres in Japan, China, and the USA were included.

RESULTS

When the AW and RW angiographically overlapped, four wire positions were seen on IVUS: (i) AW within the plaque (AW-intraplaque) and RW-intraplaque in 34%; (ii) AW-intraplaque and RW in the subintimal space (RW-subintima) in 28%; (iii) AW-subintima and RW-subintima in 22%; or (iv) AW-subintima and RW-intraplaque in 16%. The procedure succeeded without repositioning the wire in 89% of AW-intraplaque/RW-intraplaque, 61% of AW-intraplaque/RW-subintima and 57% of AW-subintima/RW-subintima, but only one (3%) AW-subintima/RW-intraplaque. Lesion and procedure complexity and failure/complications were greatest in AW-subintima/RW-intraplaque.

CONCLUSIONS

IVUS-identified vascular compartment concordance versus IVUS-identified vascular compartment mismatch leads to higher success rates irrespective of intraplaque or subintimal passage. AW-subintima/RW-intraplaque was associated with the most complex CTO morphology and procedure, and repositioning the wire was almost always necessary. Visual summary. When the antegrade wire is in the subintimal space and the retrograde wire is in the intraplaque, re-wiring is almost always necessary.

Global Chronic Total Occlusion Crossing Algorithm: JACC State-of-the-Art Review

The authors developed a global chronic total occlusion crossing algorithm following 10 steps: 1) dual angiography; 2) careful angiographic review focusing on proximal cap morphology, occlusion segment, distal vessel quality, and collateral circulation; 3) approaching proximal cap ambiguity using intravascular ultrasound, retrograde, and move-the-cap techniques; 4) approaching poor distal vessel quality using the retrograde approach and bifurcation at the distal cap by use of a dual-lumen catheter and intravascular ultrasound; 5) feasibility of retrograde crossing through grafts and septal and epicardial collateral vessels; 6) antegrade wiring strategies; 7) retrograde approach; 8) changing strategy when failing to achieve progress; 9) considering performing an investment procedure if crossing attempts fail; and 10) stopping when reaching high radiation or contrast dose or in case of long procedural time, occurrence of a serious complication, operator and patient fatigue, or lack of expertise or equipment. This algorithm can improve outcomes and expand discussion, research, and collaboration.

Right Coronary Artery Chronic Total Occlusion After Bypass Grafting Successfully Treated Using Reverse Controlled Antegrade and Retrograde Subintimal Tracking (CART) Technique via the Gastroepiploic Artery: A Case Report

Patient: Male, 63-year-old

Final Diagnosis: Chronic total coronary artery occlusion

Symptoms: Angina pectoris

Medication:—

Clinical Procedure: Percutaneous coronary intervention

Specialty: Cardiology

Iteration of Reverse Controlled Antegrade and Retrograde Tracking for Coronary Chronic Total Occlusion Intervention: a Current Appraisal

Coronary chronic total occlusion (CTO) remains one of the most challenging subsets for percutaneous coronary intervention (PCI). The retrograde recanalization is one of the most significant amendments of the technique that remains critical to improved success of CTO PCI. Currently the reverse controlled antegrade and retrograde tracking (CART) is the most dominant retrograde technique. With emergence of new equipment and important iterations, this approach has become safer, faster and more successful. In this review, the author proposes the iteration and standardization of this technique which would further facilitates its adoption with more efficacy and safety.

Percutaneous Coronary Intervention for Chronic Total Occlusion

Treatment of coronary chronic total occlusions represents one of the major challenges in the field of interventional cardiology. This is due to the complexity of these procedures and to the relatively higher risk of complications. In recent years, the development of innovative techniques and the evolution of materials have produced significant progress in this field. Better procedural outcomes have been achieved, with fewer complications. This article highlights the most recent scientific evidence and techniques, with the intention to guide interventional cardiologists in optimal patient selection and procedure choice.

From reverse CART to antegrade wire access: a guide to externalisation, tip-in, rendezvous, and snaring from the APCTO club: Reverse CART to antegrade access

We at the Asia Pacific Chronic Total Occlusion (APCTO) club, provide this review to address the gap between reverse controlled antegrade and retrograde subintimal tracking (CART) and antegrade wire access. We describe the usual method for wire externalisation. We then address how to deal with failure to wire the proximal part of the chronic total occlusion (CTO) vessel or the guiding catheter. After successful antegrade guiding catheter wiring, we address the problem of failing to cross the CTO body with the retrograde microcatheter and we recommend the use of a retrograde small balloon, reversion to traditional CART, retrograde knuckle wiring into the subintimal space and antegrade scratch and go, and external cap crush. We also propose rendezvous type tip-in and describe the way to do this to overcome problems. In conclusion, we review and make recommendations for methods to gain antegrade wire access after successful reverse CART. We have addressed each failure mode in detail covering the different options, balancing risks and success rates. Our recommendations focus upon safety first and ease of use. We hope this work will help all retrograde operators to further improve the safety, efficacy, and success rates of their retrograde procedures.

Retrograde Approach to Chronic Total Occlusion Percutaneous Coronary Intervention

The retrograde approach has increased the success rate of chronic total occlusion percutaneous coronary intervention but has also been associated with a higher risk of complications. The retrograde approach is usually performed in complex lesions, in which the antegrade approach is not feasible or has failed previously. Using a systematic 10-step approach can maximize the likelihood of success and minimize the risks of retrograde chronic total occlusion interventions.

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.

Determinants of Greater Peak radiation skin dose in percutaneous coronary intervention for chronic total occlusion

BACKGROUND

Peak skin dose (PSD) is closely associated with skin radiation injuries such as skin ulcers in percutaneous coronary intervention (PCI). Although PSD is greater in PCI for chronic total occlusion (CTO) lesions as compared with non-CTO lesions, the determinants of PSD in CTO-PCI are not fully understood. The purpose of this study was to investigate the clinical factors associated with excess PSD in PCI for CTO.

METHODS

The study population included a total of 220 CTO-PCI cases that were divided into a standard PSD group (<2 Gy, n = 187) and an excess PSD group (≥2 Gy, n = 33). Clinical, lesion, and procedural characters were compared between the 2 groups. Multivariate logistic regression was performed to investigate the clinical factors associated with excess PSD.

RESULTS

Body surface area (BSA) was significantly higher in the excess PSD group (1.85 ± 0.24 m²) than the standard PSD group (1.71 ± 0.18 m²) (p = 0.001). The J-CTO score was significantly higher in the excess PSD group (2.51 ± 1.28) than the standard PSD group (1.60 ± 1.13) (p < 0.001). Multivariate logistic regression analysis revealed that BSA (0.1 mm increase: OR 1.663, 95% CI 1.300-2.128, p < 0.001) and J-CTO score (1-point increase: OR 2.015, 95% CI 1.322-3.071, p = 0.001) were significantly associated with excess PSD.

CONCLUSIONS

A large BSA and high J-CTO score were significantly associated with excess PSD. It is important to pay special attention to CTO patients who have a large BSA and/or high J-CTO score to reduce patient's PSD.

Recanalizing left anterior descending artery chronic total occlusion with reverse controlled antegrade and retrograde tracking technology through epicardial collateral

During recent years, the reverse controlled antegrade and retrograde tracking (CART) technique has become the dominant retrograde wire crossing technique. When the retrograde guiding wire cannot pass the occlusive lesions or the guiding wire is difficult to kiss, the reverse CART technique can significantly shorten the operation time and greatly improve the success rate of the operation. In this case we succeeded in recanalizing a chronic total occlusion (CTO) lesion with reverse CART for a patient diagnosed with old myocardial infarction (OMI).

Contemporary Approach to Chronic Total Occlusion Interventions

PURPOSE OF REVIEW

Chronic total occlusion (CTO) poses one of the greatest technical challenges to interventional cardiologists. Despite recent advancements in techniques and clinical trials showing significant benefits of CTO percutaneous coronary interventions (PCI), the proportion of patients with untreated CTOs remains high. We therefore aim to perform a comprehensive review of the various techniques available, recent advancements, benefits, and complications associated with CTO PCI.

RECENT FINDINGS

Three randomized clinical trials examining the benefits of CTO PCI have recently been presented. Scoring systems have been developed to facilitate pre-procedural estimation of success and complications of CTO PCI. Technological enhancements in coronary wires and other interventional equipment along with dedicated training for CTO operators have improved the likelihood of successful recanalization of CTOs. CTO PCI has been shown to improve patient symptoms and quality of life. It is therefore important to have an in-depth knowledge of the various CTO techniques, appropriate equipment, and complications when performing these complex procedures. Clinicians should weigh the risks and benefits and choose the appropriate patient population who may benefit from revascularization.