The added value of coronary CTA in chronic total occlusion percutaneous coronary intervention: a systematic review and meta-analysis

OBJECTIVES

To systematically investigate and summarize the utility of coronary computed tomographic angiography (CCTA) in the management of chronic total occlusion (CTO)-percutaneous coronary intervention (PCI).

METHODS

The authors searched the four databases between 2005 and 2023 for studies investigating the role of CCTA and invasive coronary angiograms (ICA) images when used as the pre-procedural tool for CTO-PCI. Efficacy and safety of CCTA in CTO-PCI treatment as a pre-procedural assessment tool was evaluated.

RESULTS

Forty-seven studies were finally chosen for this systematic review. CCTA had a high degree of agreement with ICA when applied for J-CTO scoring system. A J-CTO (Multicenter CTO Registry in Japan) score > 3, together with calcification, occlusion length ≥ 20 mm, blunt stump, and bending > 45° were shared imaging risk factors on both ICA and CCTA for technique failure and guidewire crossing over 30 min. Additionally, negative remodeling and multiple diseased vessel were significant indicators on CCTA. Although patients with pre-procedural CCTA showed a trend of higher success rate and easier guidewire crossing, and CCTA showed a slightly higher predictive accuracy for process success, no significant improvement in post-PCI major adverse cardiac events of using CCTA for assessment has been achieved.

CONCLUSIONS

CCTA is a safe and effective pre-operative tool of CTO-PCI. Except for the shared imaging risk factors with ICA for a hard CTO-PCI including calcification, occlusion length ≥ 20 mm, blunt stump, bending > 45°, and J-CTO score > 3, factors like negative remodeling and multiple diseased vessel were also recognized as significant pre-operative assessment indicators on CCTA.

CLINICAL RELEVANCE STATEMENT

A pre-procedural assessment based on coronary computed tomographic angiography has the potential to aid in the management of chronic total occlusion percutaneous coronary intervention.

KEY POINTS

• A coronary computed tomographic angiography-based pre-procedural assessment can help chronic total occlusion-percutaneous coronary intervention management. • The recognized high-risk features detected via coronary computed tomographic angiography and invasive coronary angiograms are comparable in detecting difficult lesions and chronic total occlusion-percutaneous coronary intervention failure. • Coronary computed tomographic angiography has an additional value to be a safe and effective pre-procedural assessment tool for chronic total occlusion-percutaneous coronary intervention.

Coronary chronic total occlusion on coronary CT angiography: what radiologists should know?

Coronary chronic total occlusion (CTO) often occurs in patients with obstructive coronary artery disease, which remains one of the greatest challenges for interventional cardiologists. Coronary computed tomography angiography (CCTA) with its emerging post-processing techniques can provide a detailed assessment of CTO lesions before percutaneous coronary intervention (PCI), playing an important role in the clinical management of CTO PCI, from early diagnosis, pre-procedural outcome prediction, the crossing algorithm planning, intraprocedural guidance, and finally post-procedural assessment and follow-up. In addition, the feasibility of CT perfusion (CTP) in patients with CTO has been validated. Combined CCTA and CTP have the great potential to be the one-stop-shop imaging modality for assessing both anatomy and function of CTO lesions. This review aims to make radiologists understand the role of CCTA in the diagnosis and assessment of CTO lesions, thus assisting interventionalists in optimizing CTO PCI crossing strategies with the expertise of radiologists.Critical relevance statement The anatomical features of CTO on CCTA can reveal the complexity of CTO lesions and are associated with CTO PCI outcome, thus helping interventionalists optimize CTO PCI crossing strategies.Key points • CTO is the common lesion in invasive coronary angiography, and CTO PCI is technically difficult and its success rate is relatively low.• Length, collaterals, and attenuation-related signs can help distinguish CTO from subtotal occlusion.• The anatomical features of CTO lesions can help grade the difficulty of CTO PCI and predict procedural outcomes and long-term outcomes of CTO PCI.• The real-time fusion of CCTA with fluoroscopic angiography can be applied in highly complicated CTO lesions.• After CTO PCI, CCTA can help guide a second CTO PCI re-entry or follow up stent patency.

Accurate Prediction of Retrograde Collateral Channel Crossing in Coronary Artery Chronic Total Occlusion Intervention

Successful collateral channel (CC) crossing is an essential step in retrograde chronic total occlusion (CTO) percutaneous coronary interventions (PCIs). We previously developed a dedicated CC score based on CC size and tortuosity to facilitate target CC selection. Validation and comparison to other scoring systems were lacking. Thus, the aims of this study were to (1) validate the CC score in a larger independent cohort, and (2) compare its accuracy and clinical usefulness with the J-channel score. All coronary CTO PCIs attempted by experienced high-volume operators from January 2017 to December 2021 were enrolled. The CC and J-channel scores were calculated for all attempted CCs with bi-plane high-resolution cine angiography images. CC crossing success was defined as guidewire reaching the distal true lumen retrogradely. In total, 502 patients who received CTO PCI were included. The retrograde approach was utilized in 244 target CTOs, and a total of 329 CCs were attempted. The overall CC crossing rate was 67.8% (223 of 329) and final technical success rate 92.2% (225 of 244). The average CC score was 2.0 and average J-channel score was 0.71. The sensitivity and specificity of successful CC crossing with the CC score ≥2 were 81.2%, and 84.0%, respectively. Comparison between the CC score (area under the curve 0.87; 95% confidence interval 0.83 to 0.90) and the J-channel score (area under the curve 0.61, 95% confidence interval 0.55 to 0.67) demonstrated superior predictive performance of the CC score (p <0.001). The CC score was an easy-to-use and accurate tool for the prediction of successful CC crossing in retrograde CTO PCI. The CC score can help operators select the ideal target CC, thereby facilitating final procedural success.

Collateral grading systems in retrograde percutaneous coronary intervention of chronic total occlusions

BACKGROUND

The Japanese Channel (J-Channel) score was introduced to aid in retrograde percutaneous coronary intervention (PCI) of chronic total coronary occlusions (CTOs). The predictive value of the J-Channel score has not been compared with established collateral grading systems such as the Rentrop classification and Werner grade.

AIMS

To investigate the predictive value of the J-Channel score, Rentrop classification and Werner grade for successful collateral channel (CC) guidewire crossing and technical CTO PCI success.

METHODS

A total of 600 prospectively recruited patients underwent CTO PCI. All grading systems were assessed under dual catheter injection. CC guidewire crossing was considered successful if the guidewire reached the distal segment of the CTO vessel through a retrograde approach. Technical CTO PCI success was defined as thrombolysis in myocardial infarction flow grade 3 and residual stenosis <30%.

RESULTS

Of 600 patients, 257 (43%) underwent CTO PCI through a retrograde approach. Successful CC guidewire crossing was achieved in 208 (81%) patients. The predictive value of the J-Channel score for CC guidewire crossing (area under curve 0.743) was comparable with the Rentrop classification (0.699, p = 0.094) and superior to the Werner grade (0.663, p = 0.002). Technical CTO PCI success was reported in 232 (90%) patients. The Rentrop classification exhibited a numerically higher discriminatory ability (0.676) compared to the J-Channel score (0.664) and Werner grade (0.589).

CONCLUSIONS

The J-channel score might aid in strategic collateral channel selection during retrograde CTO PCI. However, the J-Channel score, Rentrop classification, and Werner grade have limited value in predicting technical CTO PCI success.

Antegrade Crossing Techniques for Hard Proximal Occlusion Caps Without the Use of Dedicated Chronic Total Occlusion Devices: A Pictorial Review

CLINICAL IMPACT

Infra-inguinal Chronic Total Occlusions recanalisation is considered technically challenging. The conventional manipulation of standard guidewires and catheters has proven to be successful in a considerable percentage of cases but success rate could dramatically drop in presence of challenging lesions. The additional use of retrograde access and re-entry devices could increase technical success but could negatively affect procedural time and overall costs. Twenty different techniques of Chronic Total Occlusions antegrade crossing are hereby described with appropriate schematic representations. The aim is to help operators to apply them in specific anatomy subsets and clinical presentations and ultimately to increase procedural success rate.

A Chinese scoring system for predicting successful retrograde collateral traverse in patients with chronic total coronary occlusion

BACKGROUND

Retrograde approach technique has been challenging in percutaneous coronary interventional treatment of chronic total occlusion (CTO) coronary disease. The present study endeavors to determine a novel Chinese scoring system for predicting successful collateral channels traverse via retrograde approach.

METHODS

The demographic characteristics and angiographic characteristics of 309 CTO patient were analyzed by univariable and multivariable analysis for selecting potential predictors. And the nomogram was used to establish the scoring system. Then it was evaluated by the internal and external validation.

RESULTS

The predictors of Age, Connections between collateral channels and recipient vessels, and Channel Tortuosity (ACT) were identified with univariable and multivariable analysis and employed to the ACT score system. With acceptable calibrations, the area under curve of the scoring system and the external validation were 0.826 and 0.816 respectively. Based on score, the predictors were divided into three risk categories and it showed a consistent prediction power in the validation cohort.

CONCLUSIONS

The novel Chinese ACT score is a reliable tool for predicting successful retrograde collateral traverse.

Overview of Contemporary Chronic Total Occlusion Percutaneous Coronary Intervention Techniques: A Narrative Systematic Review

BACKGROUND

Despite the abundance of coronary chronic total occlusions (CTO) percutaneous coronary intervention (PCI) studies, the literature is not easy to digest for both general PCI operators and CTO PCI specialists because of the many varied terms used for approaches and inconsistency in terminology. This inconsistency makes it challenging to understand the advantages and disadvantages of these different approaches and, most importantly, their downstream clinical outcomes. Accordingly, we conducted a systematic review of all published studies on CTO PCI to describe techniques and algorithms used in the last decade to provide an overview on the efficacy and safety of contemporary CTO PCI techniques.

METHODS

We performed a comprehensive search of the PubMed, EMBASE, and the Cochrane library databases for manuscripts about PCI of CTOs. We included studies published between the years 2005 and 2019. We categorized studies into those using a single approach (antegrade, retrograde) and those with a prespecified algorithm (ie, hybrid approach).

RESULTS

Fifty-five observational studies including 28,907 patients who underwent CTO were included in this review. CTO PCI generally carries low risk of major procedural complications, with angiographic success rates being higher in studies that used an algorithmic vs single technical approach.

CONCLUSIONS

This systematic review highlights the wide variation in definitions and practices in CTO PCI and calls for standardization in terminology and practice.

Procedural Success Prediction Scoring Systems Used in Percutaneous Coronary Interventions for Chronic Total Occlusions: A Systematic Evaluation

(1) Background: Data suggest that patients with coronary chronic total occlusion (CTO) managed with percutaneous coronary intervention (PCI) could have better outcomes than those treated with optimal medical therapy alone. We aimed to systematically review dedicated scoring systems used to predict successful PCI in patients with CTO. (2) Methods: Electronic databases of MEDLINE (PubMed), Embase, and Cochrane were searched. (3) Results: 32 studies were included. We provided insights into all available predictive models of PCI success in CTO including predictive performance, validations, and comparisons between different scores and models' limitations. Considering the differences in the population included, coronary lesions, and techniques applied across clinical studies, the most used scores displayed a modest to good predictive value, as follows: J-CTO (AUC, 0.55-0.868), PROGRESS-CTO (AUC, 0.557-0.788), CL (AUC, 0.624-0.800), CASTLE (AUC, 0.633-0.68), and KCCT (AUC, 0.703-0.776). As PCI for CTO is one of the most complex interventions, using dedicated scoring systems could ensure an adequate case selection as well as preparation for an appropriate recanalization technique in order to increase chances of successful procedure. (4) Conclusion: Clinical models appear to be valuable tools for the prediction of PCI success in CTO patients. Clinicians should be aware of the limitations of each model and should be able to correctly select the most appropriate score according to real-life case particularities such as lesion complexity and operator experience in order to maximize success and achieve the best patients' outcomes.

Preprocedure Planning for Chronic Total Occlusion Percutaneous Coronary Intervention: The Separation Is in the Preparation

To perform chronic total occlusion percutaneous coronary intervention safely, efficiently, and successfully, adequate time must be dedicated to thorough preprocedural planning. This process should encompass a patient encounter, becoming fully familiarized with the patient's clinical traits, a detailed review of coronary anatomy, laying out an algorithmic procedural approach and making any relevant plans for actions that will enhance intraprocedural safety.

Collateral Channel Size and Tortuosity Predict Retrograde Percutaneous Coronary Intervention Success for Chronic Total Occlusion

BACKGROUND

There is little evidence on how to select an interventional collateral channel (CC) in retrograde chronic total occlusion (CTO) percutaneous coronary intervention. We aimed to identify independent angiographic predictors of CC tracking and technical success in retrograde CTO percutaneous coronary intervention.

METHODS AND RESULTS

From January 2012 to December 2015, a total of 216 consecutive retrograde CTO percutaneous coronary intervention attempts by a high-volume operator in a tertiary university-affiliated hospital were enrolled. The clinical, angiographic, and procedural details were collected. The characteristics analyzed included channel type, size, tortuosity, angle of attack, length to emerging point, and the Multicenter CTO Registry of Japan score. The Multicenter CTO Registry of Japan score was 4.2±0.8. A total of 242 CCs were attempted for intervention. CC tracking success rate was 83.5%, and the technical success rate (per CC) was 81.4%. The per-patient technical success rate was 91.2%, and the major procedural complication rate was 4.6%. The atrioventricular groove, epicardial, and septal CCs were used in 36 (14.9%), 84 (34.7%), and 122 (50.4%) tracking attempts, respectively. In multivariable analysis, only large channel size and lack of tortuosity were significant independent predictors of CC tracking and technical success. A new scoring system was developed, while large size was given 1 point and lack of tortuosity was given 2 points. The receiver-operating characteristic area by the new model to predict CC tracking and technical success were 0.800 and 0.752, respectively.

CONCLUSIONS

In retrograde CTO percutaneous coronary intervention, only size and tortuosity of a CC are independent angiographic predictors of CC tracking and technical success.

Use of sodium nitroprusside in retrograde percutaneous coronary intervention for chronic total occlusion: A case report

RATIONALE

Chronic total occlusion continues to be a challenging lesion subset for percutaneous coronary intervention.

PATIENT CONCERNS

A 65-year-old male patient was admitted with symptoms of angina pectoris for 9 months.

DIAGNOSES

Coronary angiography showed a severe stenosis in the proximal left anterior descending artery and a chronic total occlusion (CTO) in the proximal right coronary artery. The complexity of the CTO was stratified using the J-CTO score and the PROGRESS CTO score.

INTERVENTIONS

Antegrade wire escalation for CTO of RCA failed. The septal collaterals to RCA were initially judged to be poor and not suitable for intervention.

OUTCOMES

However, administration of sodium nitroprusside improved collateral flow and enabled the identification of retrograde channels suitable for wire crossing and successful retrograde PCI.

LESSIONS

The study showed that faintly visible to even invisible septal collateral connections can be crossed with the septal "trial and error" surfing technique after the administration of sodium nitroprusside.

Epicardial collateral channel for retrograded recanalization of chronic total occlusion percutaneous coronary intervention: Predictors of failure and procedural outcome

OBJECTIVES

This study set out to identify significant lesion features of chronic total occlusion (CTO) that predict successful retrograde recanalization via epicardial collateral channels (CCs).

BACKGROUND

Epicardial CCs remain essential in retrograde percutaneous coronary intervention (PCI) of CTO. However, the unpredictability of success and occurrence of complications limit the application of epicardial CCs for retrograde PCI technique for CTO.

METHODS

103 retro-recanalization cases were analyzed using epicardial CCs with successful recanalization as an end point. Clinical and angiography data were collected.

RESULTS

The total success rate was 76.3%. Independent predictors associated with technical success included CCs tortuosity, side branch at CCs tortuosity, inadequate CCs Size and inadequate CCs exit location. Assigning a score of one for each variable, four levels of difficulty were obtained and formed the EPI-CTO score (Epicardial CTO). This score had significant predictive value for the likelihood of successful recanalization (AUC: 0.94, 95%CI: 0.89-0.98). Coronary and CCs perforation occurred in 6 and 10 cases respectively. Four cases including two coronary and two CCs perforations had tamponade that needed pericardiocentesis.

CONCLUSIONS

Using epicardial CCs for retrograde approach of CTO PCI is effective. Complication rate was acceptable. We found four independent predictors relative to procedure success.

Usefulness and Safety of a Novel Modification of the Retrograde Approach for the Long Tortuous Chronic Total Occlusion of Coronary Arteries

The aim of this study was to evaluate the feasibility and efficacy of the Guidezilla guide extension catheter in a reverse controlled antegrade and retrograde subintimal tracking (CART) technique for chronic total occlusion (CTO) recanalization.We retrospectively collected 80 CTO cases using reverse CART technology from January 2015 to October 2015 and 20 CTO cases using Guidezilla reverse-CART technology from October 2015 to March 2016. Guidezilla was applied in cases when it was difficult to advance a retro-guidewire through an occlusion segment into the antegrade guide catheter.The Guidezilla group had more cases with an occlusion longer > 20 mm (100.0% versus 72.5%, P = 0.005) and "bending > 45°" (90.0% versus 63.7%, P = 0.029) than the non-Guidezilla group, while the non-Guidezilla group had more retry lesions (25.0% versus 63.8%, P = 0.002). The septal collateral channel was the preferred choice for retro-recanalization in both groups (90.0% in Guidezilla group and 68.8% in non-Guidezilla group). All cases in the Guidezilla group achieved technical success with a TIMI 3 flow in the distal true lumen (100.0% versus 75.0% in non-Guidezilla group, P = 0.010). Cardiac tamponade and perforation in the epicardial artery was observed in 1 case each in the Guidezilla group. In the non-Guidezilla group, 19 complications occurred during the PCI procedure. No target vessel revascularization or in-hospital death occurred in either group.CTO lesions using the Guidezilla guide extension catheter to facilitate entry to an antegrade catheter in reverse CART technology is convenient and safe with a high success rate.

Approach to CTO Intervention: Overview of Techniques

OPINION STATEMENT

Successful percutaneous coronary intervention (PCI) of chronic total occlusions (CTOs) has been associated with significant clinical benefits, but remains technically demanding. Failure to cross the CTO with a guidewire is the most common cause of CTO PCI failure. CTO crossing can be achieved in the antegrade or retrograde direction and can be accomplished by maintaining true lumen position throughout or via subintimal dissection/reentry techniques. A procedural plan should be created prior to the procedure through careful angiographic review of four key parameters: (a) morphology of the proximal occlusion cap; (b) length of the occlusion; (c) quality of the distal vessel and presence of bifurcation at the distal cap; and (d) suitability of collateral circulation for retrograde crossing. Dual coronary injection is recommended in all cases with contralateral collaterals for detailed characterization of the lesion. If one approach fails to progress, a quick transition to the next approach is encouraged to maximize efficacy and efficiency. Procedural complications, including vessel perforation, may occur more frequently in CTO as compared with non-CTO PCI; hence, availability of necessary equipment and expertise in treating such complications are essential.