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

Applicability of J-CTO channel score to predict microcatheter tracking during retrograde percutaneous coronary intervention of chronic total occlusions: Insights from the SURFING MICRO registry

BACKGROUND

The J-chronic total occlusion (CTO) channel score can predict guidewire tracking of the collateral channels (CCs), but its efficacy in predicting microcatheter tracking has never been tested in the setting of retrograde CTO-percutaneous coronary intervention (PCI).

AIMS

Predicting microcatheter collateral tracking during retrograde CTO-PCIs.

METHODS

A total of 189 patients undergoing retrograde CTO-PCI from April 2017 to August 2021 were screened. The primary outcome of interest was a correlation between J-CTO channel score and microcatheter tracking failure (MTF) after successful CC tracking by the guidewire. The independent association between anatomical features of the J-CTO channel score and the primary outcome of interest was explored.

RESULTS

After adjustment, only small size (adjusted OR: 12.70, 95% confidence interval [CI]: 1.79-89.82; p = 0.01) and continuous bends (adjusted OR: 14.15, 95% CI: 2.77-72.34; p < 0.001) remained significantly associated with an increased risk of MTF for septal collaterals. The small size was the only predictor of the MTF for epicardial collaterals (OR: 6.39, 95% CI: 1.13-35.96; p = 0.020) at univariate analysis. Patients in the MTF group had a lower incidence of procedural success compared with patients in the microcatheter tracking success (MTS) group (40.0% vs. 93.9%, p < 0.001) and had a higher incidence of collateral perforations (20.0% vs. 3.0%, p < 0.001).

CONCLUSION

Small and tortuous septal collaterals, identified by a score ≥3, are associated with an increased risk of MTF, lower incidence of procedural success, and higher risk of procedural complications driven by collateral perforations.

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.

Chronic total occlusion percutaneous coronary intervention: managing perforation complications

INTRODUCTION

Coronary artery perforation (CAP) is an infrequent (<1%) complication of percutaneous coronary intervention (PCI), that can lead to dramatic consequences, including tamponade and death. The incidence of CAP is higher (4-9%) in chronic total occlusion (CTO) PCI due higher complexity of these lesions and the techniques used to recanalized them.

AREAS COVERED

In this Expert Review, we discuss the specific features of CTO PCI predisposing to CAP. We also describe the typical procedural scenarios in which CAP can occur and provide a universal management algorithm. Currently available devices and techniques for CAP treatment are presented in detail. Finally, we discuss imaging support for diagnosis of pericardial effusion in CAP as well as medical and surgical management.

EXPERT OPINION

With increasing volumes and complexity of CTO PCI, the incidence of CAP is likely to rise. Adherence to good catheterization laboratory practices, availability of dedicated equipment to seal CAP, perform pericardiocentesis, and provide hemodynamic support, as well as adequate training, are pillars for the prevention and optimal management of CAP during CTO PCI.

Incidence, Predictors, and Strategies for Failure of Retrograde Microcatheter Tracking After Successful Wiring of Septal Collateral Channels in Chronic Total Occlusions

Background

Retrograde microcatheter collateral channel (CC) tracking after successful wiring of septal CC is crucial for retrograde revascularization of coronary chronic total occlusion (CTO). However, the incidence, predictors, and strategies for failure of retrograde microcatheter CC tracking after successful wiring of septal CC remain unclear.

Methods

In total, 298 patients with CTO who underwent retrograde septal CC PCI between January 2015 and May 2019 were retrospectively analyzed. Clinical data were compared to investigate the predictors of initial microcatheter tracking failure.

Results

The initial and final microcatheter tracking success rates were 79.2% (236/298) and 96.6% (288/298), respectively. The procedural success rate was 94.0% (280/298). The right coronary artery-to-left anterior descending artery septal ratio (48.4% vs 33.1%, p=0.037) and CC tortuosity (34.6% vs 20.8%, p=0.045) were significantly higher in the initial microcatheter CC tracking failure group than in the successful tracking group. Multivariate logistic regression analysis revealed that severe collateral tortuosity (odds ratio [OR]: 13.241, 95% confidence interval [CI]: 3.429–27.057, p=0.038), CC entry angle of <90° (OR:4.921, 95% CI: 1.128–9.997, p=0.002), CC exit angle of <90° (OR:5.037, 95% CI: 2.237–11.182, p=0.004), use of Finecross MG as initial microcatheter (OR:1.826, 95% CI: 1.127–3.067, p=0.035), and shunning initial retrograde application of Guidezilla (OR:0.321, 95% CI: 0.267–0.915, p=0.024) were variables independently associated with initial microcatheter CC tracking failure in patients with CTO undergoing retrograde septal CC PCI.

Conclusion

The overall initial microcatheter CC tracking failure was 20.8%. Severecollateral tortuosity, CC entry, and exit angle of <90°, use of Finecross MG as initial microcatheter, and shunning initial retrograde application of Guidezilla were variables independently associated with initial microcatheter CC tracking failure in patients with CTO undergoing retrograde septal PCI.

Active Retrograde Extra Backup with a Mother-and-Child Catheter to Facilitate Retrograde Microcatheter Collateral Channel Tracking in Recanalization of Coronary Chronic Total Occlusion

OBJECTIVE

To explore the feasibility and safety of the active retrograde backup (ARB) for treatment of chronic total occlusion (CTO) during retrograde percutaneous coronary intervention (PCI).

BACKGROUND

Guiding support plays an important role in guidewire and microcatheter coronary channel (CC) tracking in retrograde PCI therapy for patients with CTO. However, the feasibility and safety of retrograde active use of a mother-and-child catheter are still unclear. Patients and Methods. A total of 271 consecutive patients with CTO who underwent retrograde PCI between January 2015 and January 2020 were retrospectively analyzed. Clinical data of two groups were compared to evaluate the feasibility and safety of ARB.

RESULTS

Of the 271 patients, 69.0% (187/271) underwent therapy through the septal branch, 31.0% (84/271) through the epicardial collateral channel, and 47.6% (129/271) through active retrograde extra backup with a mother-and-child catheter to facilitate retrograde microcatheter collateral CC tracking. The time of wire CC tracking was shorter in the ARB group than that in the non-ARB group (25.4 ± 8.5 vs 26.4 ± 9.7, p=0.348), but there was no significant difference. The duration of the retrograde microcatheter tracking (10.2 ± 3.8 vs 15.5 ± 6.8, p=0.012) and the retrograde approach (62.8 ± 20.3 vs 70.4 ± 24.3, p=0.026) in the ARB group was significantly shorter than that in the non-ARB group. The radiation dose (223.6 ± 112.7 vs. 295.2 ± 129.3, p=0.028), fluoroscopy time (50.6 ± 21.3 vs 62.3 ± 32.1, p=0.030), and contrast volume (301.8 ± 146.7 vs 352.2 ± 179.5, p=0.032) in the ARB group were significantly lower than that in the non-ARB group. There were no life-threatening procedural complications in either group. Complications unrelated to ARB included two cases of donor-vessel dissection, one case of CC perforation, and two cases of target-vessel perforation. There was no statistically significant difference in major adverse cardiac and cerebrovascular events between the groups during hospitalization (p > 0.05).

CONCLUSION

ARB is feasible, safe, and conducive to guidewire and microcatheter CC tracking in the recanalization of coronary CTO. It improves procedural efficiency and is worthy of further promotion.

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.

Predictors, treatment, and long-term outcomes of coronary perforation during retrograde percutaneous coronary intervention via epicardial collaterals for recanalization of chronic coronary total occlusion

OBJECTIVE

To investigate predictors, treatment, and long-term outcomes associated with coronary perforation (CP) in patients who underwent retrograde percutaneous coronary intervention (PCI) through epicardial collaterals for chronic total occlusion (CTO).

BACKGROUND

Data regarding CP during retrograde PCI through epicardial collaterals for CTO are scarce.

METHODS

We included 155 patients who underwent retrograde CTO PCI through epicardial collaterals at Guangdong Cardiovascular Institute from August 2011 to December 2017. The median follow-up was 2.5 years. Major adverse cardiac events (MACEs) were analyzed using the Kaplan-Meier method, and independent predictors of long-term MACE were determined using a multivariable Cox model.

RESULTS

CP occurred in 24 (15.5%) patients, with the frequency of Ellis classes 1 or 2 and 3 being 41.7% and 58.3%, respectively. Seven (4.5%) patients had tamponade, which was effectively managed using coil embolization and pericardiocentesis. Renal dysfunction (odds ratio [OR]: 5.27; 95% confidence interval [CI]: 1.47-18.88; P = 0.011), right coronary artery (RCA) CTO (OR: 4.34; 95% CI: 1.29-14.63; P = 0.018), and Epi-CTO score ≥ 2 (OR: 3.27; 95% CI: 1.12-9.58; P = 0.030) were independent predictors of CP. At the 7-year follow-up, 17 patients had MACE. Multivariable analysis revealed that CP was not associated with worse long-term clinical outcomes (hazard ratio: 1.55; 95% CI: 0.45-5.32, P = 0.484).

CONCLUSIONS

Retrograde CTO PCI through epicardial collaterals is at increased risk of CP, which is associated with renal dysfunction, RCA CTO, and Epi-CTO score ≥ 2. Prompt and proper management of CP is important. CP is not significantly associated with adverse clinical outcomes.