Outcomes of Percutaneous Coronary Interventions for Chronic Total Occlusion Performed by Highly Experienced Japanese Specialists

Impact of successful antegrade and retrograde CTO PCI on short-term prognosis

BACKGROUND

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) carries risk of complications and should be attempted when the anticipated benefits exceed the potential risks. The primary indication for CTO-PCI is symptom improvement. However, the impact of CTO-PCI on angina and subsequent incidence of major adverse cardiovascular event (MACE) rate remains controversial. Our aim was to study the impact of technically successful elective CTO-PCI on the procedural success rate and short-term MACE. The current study was a prospective cohort study that included a total of 80 patients who were referred to our center (Ain Shams University Hospitals) for elective CTO-PCI and underwent technically successful CTO-PCI. Data were collected on patient arrival to our department, and then, the patients were observed during hospital admission to record any In-Hospital MACE. These patients were then followed up for 6 months to record improvement or worsening of their symptoms and to assess occurrence of any MACE including hospitalization and undergoing symptom-driven coronary angiography.

RESULTS

The mean age of our patients was 56 ± 9.6 years, and 73 patients (91%) were men. Sixty-two patients (77.5%) were done via an antegrade approach, and 18 patients (22.5%) were done via a retrograde approach with an overall procedural success rate of 91.25% (antegrade 93.5%, retrograde 83.3%). The overall mean procedure time was 102 min, the mean contrast volume used was 371 ml, and the mean cumulative air kerma dose was 7.2 Gy. The retrograde group required longer procedure times, larger volumes of contrast and higher exposure to radiation. The overall in-hospital MACE was 8.75%. Sixty-five patients in our study (81.25%) showed an improvement in the grade of their exertional dyspnea or angina within the 6-month follow-up period. Thirteen patients in our study (16.25%) needed re-hospitalization within a 6-month period after PCI. The overall target lesion revascularization rate at 6 months was 8.75%.

CONCLUSIONS

Technically successful CTO PCI in a well-equipped center with highly qualified CTO operators resulted in high procedural success rates and low incidence of short-term MACE.

The Characteristics of Primary Retrograde Approach Selection for Native Coronary Chronic Occlusion With Short Occlusion Length from the Japanese CTO-PCI Expert Registry

Although the coronary chronic total occlusion (CTO) crossing algorithm has been published, the characteristics associated with the first strategy selection for short-length lesions <20 mm is still debatable. This study aimed to determine the characteristics associated with primary retrograde approach (PRA) for native CTO with short occlusion length in percutaneous coronary intervention (PCI). Between January 2014 and December 2021, we examined data on 4,088 lesions in the Japanese CTO-PCI Expert Registry with occlusion lengths <20 mm. Then, the characteristics for short-length CTO, which was performed by way of the PRA, were assessed. PRA was performed in 785 patients (19.2%). The guidewire success rate was 93.6%, and the technical success rate was 91.3%. Previous coronary artery bypass grafting, chronic kidney disease, and 6 lesion/anatomic characteristics (i.e., blunt stump, distal runoff <1 mm, CTO lesion tortuosity, reattempt procedures, ostial location, and the presence of collateral channel grade 2) were associated with PRA (p <0.05). Moreover, hemodialysis was an independent factor of unsuccessful anterograde guidewire crossing, along with distal runoff <1 mm, the existence of calcification, and CTO lesion tortuosity (all p <0.05). In clinical settings, these independent factors for PRA in short-length CTO can help in selecting the CTO-PCI strategy.

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 objective 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.

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.

Contemporary outcomes of chronic total occlusion percutaneous coronary intervention in Europe: the ERCTO registry

BACKGROUND

Percutaneous coronary interventions (PCI) of chronic total occlusions (CTO) have reached high procedural success rates thanks to dedicated equipment, evolving techniques, and worldwide adoption of state-of-the-art crossing algorithms.

AIMS

We report the contemporary results of CTO PCIs performed by a large European community of experienced interventionalists. Furthermore, we investigated the impact of different risk factors for procedural major adverse cardiac and cerebrovascular events (MACCE) and trends of employment of specific devices like dual lumen microcatheters, guiding catheter extensions, intravascular ultrasound and calcium-modifying tools.

METHODS

We evaluated data from 8,673 CTO PCIs included in the European Registry of Chronic Total Occlusion (ERCTO) between January 2021 and October 2022.

RESULTS

The overall technical success rate was 89.1% and was higher in antegrade as compared with retrograde cases (92.8% vs 79.3%; p<0.001). Compared with antegrade procedures, retrograde procedures had a higher complexity of attempted lesions (Japanese CTO [J-CTO] score: 3.0±1.0 vs 1.9±1.2; p<0.001), a higher procedural and in-hospital MACCE rate (3.1% vs 1.2%; p<0.018) and a higher perforation rate with and without tamponade (1.5% vs 0.4% and 8.3% vs 2.1%, respectively; p<0.001). As compared with mid-volume operators, high-volume operators had a higher technical success rate in antegrade and retrograde procedures (93.4% vs 91.2% and 81.5% vs 69.0%, respectively; p<0.001), and had a lower MACCE rate (1.47% vs 2.41%; p<0.001) despite a higher mean complexity of the attempted lesions (J-CTO score: 2.42±1.28 vs 2.15±1.27; p<0.001).

CONCLUSIONS

The adoption of different recanalisation techniques, operator experience and the use of specific devices have contributed to a high procedural success rate despite the high complexity of the lesions documented in the ERCTO.

Interventions in chronic total occlusions with bifurcation lesions: incidence, treatment, and in-hospital outcome

INTRODUCTION AND OBJECTIVES

Coronary chronic total occlusions (CTO) involving bifurcation lesions are a challenging lesion subset that is understudied in the literature. This study analyzed the incidence, procedural strategy, in-hospital outcomes and complications of percutaneous coronary interventions (PCI) for bifurcation-CTO (BIF-CTO).

METHODS

We assessed data from 607 consecutive CTO patients treated at the Institut Cardiovasculaire Paris Sud (ICPS), Massy, France between January 2015 and February 2020. Procedural strategy, in-hospital outcomes and complication rates were compared between 2 patient subgroups: BIF-CTO (n=245=and non-BIF-CTO (n=362).

RESULTS

The mean patient age was 63.2±10.6 years; 79.6% were men. Bifurcation lesions were involved in 40.4% of the procedures. Overall lesion complexity was high (mean J-CTO score 2.30±1.16, mean PROGRESS-CTO score 1.37±0.94). The preferred bifurcation treatment strategy was a provisional approach (93.5%). BIF-CTO patients presented with higher lesion complexity, as assessed by J-CTO score (2.42±1.02 vs 2.21±1.23 in the non-BIF-CTO patients, P=.025) and PROGRESS-CTO score (1.60±0.95 vs 1.22±0.90 in the non-BIF-CTO patients, P<.001). Procedural success was 78.9% and was not affected by the presence of bifurcation lesions (80.4% in the BIF-CTO group, 77.8% in the non-BIF-CTO-CTO group, P=.447) or the bifurcation site (proximal BIF-CTO 76.9%, mid-BIF-CTO 83.8%, distal BIF-CTO 85%, P=.204). Complication rates were similar in BIF-CTO and non-BIF-CTO.

CONCLUSIONS

The incidence of bifurcation lesions is high in contemporary CTO PCI. Patients with BIF-CTO present with higher lesion complexity, with no impact on procedural success or complication rates when the predominant strategy is provisional stenting.

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.

Impact of calcium on the procedural techniques and outcomes of chronic total occlusion percutaneous coronary intervention

BACKGROUND

Coronary calcification is common and increases the difficulty of chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

METHODS

We examined the impact of calcium on procedural outcomes of 13,079 CTO PCIs performed in 12,799 patients at 46 US and non-US centers between 2012 and 2023.

RESULTS

Moderate or severe calcification was present in 46.6% of CTO lesions. Patients whose lesions were calcified were older and more likely to have had prior coronary artery bypass graft surgery. Calcified lesions were more complex with higher J-CTO score (3.0 ± 1.1 vs. 1.9 ± 1.2; p < 0.001) and lower technical (83.0% vs. 89.9%; p < 0.001) and procedural (81.0% vs. 89.1%; p < 0.001) success rates compared with mildly calcified or non-calcified CTO lesions. The retrograde approach was more commonly used among cases with moderate/severe calcification (40.3% vs. 23.5%; p < 0.001). Balloon angioplasty (76.6%) was the most common lesion preparation technique for calcified lesions, followed by rotational atherectomy (7.3%), laser atherectomy (3.4%) and, intravascular lithotripsy (3.4%). The incidence of major adverse cardiovascular events (MACE) was higher in cases with moderate or severe calcification (3.0% vs. 1.2%; p < 0.001), as was the incidence of perforation (6.5% vs. 3.4%; p < 0.001). On multivariable analysis, the presence of moderate/severe calcification was independently associated with lower technical success (odds ratio, OR = 0.73, 95% CI: 0.63-0.84) and higher MACE (OR = 2.33, 95% CI: 1.66-3.27).

CONCLUSIONS

Moderate/severe calcification was present in nearly half of CTO lesions, and was associated with higher utilization of the retrograde approach, lower technical and procedural success rates, and higher incidence of in-hospital MACE.

Long-term clinical outcomes following successful percutaneous coronary intervention in patients with extremely long coronary chronic total occlusion lesions

BACKGROUND

Lesion length is related to worse clinical outcomes following percutaneous coronary intervention (PCI) for the treatment of chronic total occlusion (CTO). However, the data to confirm the association between extremely long lesions and clinical hard endpoints have been limited. Therefore, we investigated the impact of extremely long CTO lesions (≥50 mm, treated lesion length) on the long-term clinical outcomes following successful PCI.

METHODS

A total of 333 consecutive patients with CTO who underwent successful PCI with drug-eluting stents (DESs) were allocated to either the extremely long or the short CTO group according to their CTO lesion length. The 5-year clinical outcomes were compared between the two groups. The incidence of myocardial infarction, cardiac death (CD), revascularization, and major adverse cardiovascular events (MACE) was higher in the extremely long CTO group. The 5-year clinical outcomes were analyzed using the Cox hazard ratio (HR) model.

RESULTS

In the entire study population, the extremely long CTO lesion was an independent predictor for higher rate of revascularization, MACE, CD, or mortality.

CONCLUSIONS

In our study, CTO patients with extremely long lesions (≥50 mm) who underwent successful PCI were associated with a higher risk of worse long-term clinical outcomes, including hard clinical endpoints such as CD and mortality even in the DESs era.

Outcomes of chronic total occlusion percutaneous coronary intervention from the RAIAN (RAjaie - Iran) registry

OBJECTIVE

While most of the evidence in CTO interventions emerge from Western and Japanese studies, few data have been published up today from the Middle East. Objective of this study was to evaluate technical success rates and clinical outcomes of an Iranian population undergoing CTO PCI in a tertiary referral hospital. Moreover, we sought to evaluate the efficacy of our CTO teaching program.

METHODS

This is a retrospective single-center cohort study including 790 patients who underwent CTO PCI performed by operators with different volumes of CTOs PCI performed per year. According to PCI result, all patients have been divided into successful (n = 555, 70.3 %) and unsuccessful (n = 235, 29.7 %) groups. Study endpoints were Major Adverse Cardiovascular Events and Health Status Improvement evaluated using the Seattle Angina Questionnaire at one year.

RESULTS

A global success rate of 70 % for antegrade and 80 % for retrograde approach was shown despite the lack of some CTO-dedicated devices. During the enrollment period, the success rate increased significantly among operators with a lower number of CTO procedures per year. One-year MACE rate was similar in both successful and unsuccessful groups (13.5 % in successful and 10.6 % in unsuccessful group, p = 0.173). One year patients' health status improved significantly only in successful group.

CONCLUSIONS

No significant differences of in-hospital and one-year MACE were found between the successful and unsuccessful groups. Angina symptoms and quality of life significantly improved after successful CTO PCI. The RAIAN registry confirmed the importance of operator expertise for CTO PCI success.

New Angiographic Difficulty Score for First-Attempt Chronic Total Occlusion in the 3 Major Coronary Arteries

BACKGROUND

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) is still challenging due to complex lesion morphology. Success rates may vary among the 3 major coronary arteries, influenced by clinical and angiographic characteristics.

OBJECTIVES

This study sought to evaluate the differences in the predictors of unsuccessful PCI in first-attempt CTO lesions of the 3 major coronary arteries compared with the J-CTO (Japanese CTO) score.

METHODS

This study assessed 6,408 first-attempt CTO patients from the Japanese CTO-PCI expert registry between January 2014 and December 2021, randomly assigned to derivation and validation sets. Difficulty scores for each artery were determined by assigning points to predictive unsuccessful factors.

RESULTS

The CTO lesions were distributed as follows: left anterior descending coronary artery: 2,245 (35%), left circumflex coronary artery: 1,131 (18%), and right coronary artery (RCA): 3,032 (47%). Regarding success rates, left circumflex coronary artery CTO had the lowest procedural success rate (90%) followed by RCA CTO (92%) and left anterior descending coronary artery CTO (94%). RCA CTO was significantly longer and more severely angulated, requiring more often the retrograde approach. A multivariate logistic analysis revealed that predictors of failed PCI were different in CTO lesions among the 3 major coronary arteries, respectively. Moreover, our difficulty score for RCA CTO was superior to the J-CTO score in predicting unsuccessful PCI.

CONCLUSIONS

Clinical and angiographic differences might explain the discrepancies of success rates in CTO lesions among the 3 major coronary arteries. Our novel difficulty score was comparable to the J-CTO score in predicting unsuccessful CTO-PCI with a superior discriminatory capacity.

Antegrade wire escalation in chronic total occlusions: State of the art review

Coronary chronic total occlusion percutaneous coronary intervention treatment algorithms have helped to standardize crossing strategy sequence to improve efficacy and efficiency of CTO interventions based on angiographic criteria. Unfortunately, advanced crossing techniques such as a retrograde and subintimal guidewire tracking and reentry that have accelerated procedural success in more difficult lesions are associated with higher major adverse cardiac event rates as compared with traditional antegrade and intimal guidewire tracking. In this regard, antegrade wire escalation (AWE) remains the most common CTO crossing strategy. In this state of the art review, we outline the techniques employed to maximize the clinical utility of AWE crossing strategy for both novice operators as well as those experienced with the advanced crossing strategies. For the less experienced operator, these techniques may provide a framework to treat more patients safely and effectively without the need to refer to a more advanced operator. Whereas these same techniques may be employed by an advanced operator to improve the technical success in procedures requiring more advanced crossing strategies.

Temporal trends of case-fatality in patients undergoing dual-injection coronary chronic total occlusion recanalization

AIMS

Recently, interventional techniques and material to treat chronic total occlusion (CTO) with percutaneous coronary intervention (PCI) have evolved significantly. Nevertheless, it is still unknown whether this progress improved treatment success and patients' outcome. In a nationwide sample, we sought to analyze trends of patients' characteristics, complications and in-hospital case-fatality of patients undergoing CTO revascularization in Germany.

METHODS AND RESULTS

We analyzed data on characteristics, treatments, and in-hospital outcomes for all coronary artery disease (CAD) patients (ICD-code I25) undergoing dual-injection CTO recanalization (OPS procedural code: 8-839.9) in Germany from 2009 to 2020. Overall, 4,998,457 inpatients aged ≥ 18 years with diagnosis of CAD were treated in German hospitals in this period. Among these, 52,879 patients (1.1%) underwent CTO recanalization. Annual number of CTO PCIs increased from 1263 in 2009 to 6435 in 2020 (β 3.48 [95% CI 3.44-3.52]; p < 0.001) in parallel with a significant decrease of case-fatality (2.2% in 2009 to 1.4% in 2020; β  - 0.60 [95% CI  - 0.82 to  - 0.39]; p < 0.001). Overall, 754 (1.4%) patients with CTO recanalization died during the in-hospital stay and in-hospital case-fatality grew exponentially with age (β 0.82 [95% CI 0.73-0.90]; p < 0.001). Significant predictors of in-hospital case fatality with an OR > 3 were cancer, stroke, hemopericardium, acute renal failure, pulmonary embolism and shock.

CONCLUSION

Annual number of CTO procedures performed in Germany increased from 2009 to 2020 with a concomitant anti-proportional decrease in the case-fatality. Our findings may help to draw more attention to predictors of in-hospital case fatality in patients hospitalized for CTO recanalization.

Development of a Novel Score to Predict Urgent Mechanical Circulatory Support in Chronic Total Occlusion Percutaneous Coronary Intervention

Estimating the likelihood of urgent mechanical circulatory support (MCS) can facilitate procedural planning and clinical decision-making in chronic total occlusion (CTO) percutaneous coronary intervention (PCI). We analyzed 2,784 CTO PCIs performed between 2012 and 2021 at 12 centers. The variable importance was estimated by a bootstrap applying a random forest algorithm to a propensity-matched sample (a ratio of 1:5 matching cases with controls on center). The identified variables were used to predict the risk of urgent MCS. The performance of the risk model was assessed in-sample and on 2,411 out-of-sample procedures that did not require urgent MCS. Urgent MCS was used in 62 (2.2%) of cases. Patients who required urgent MCS were older (70 [63 to 77] vs 66 [58 to 73] years, p = 0.003) compared with those who did not require urgent MCS. Technical (68% vs 87%, p <0.001) and procedural success (40% vs 85%, p <0.001) was lower in the urgent MCS group compared with cases that did not require urgent MCS. The risk model for urgent MCS use included retrograde crossing strategy, left ventricular ejection fraction, and lesion length. The resulting model demonstrated good calibration and discriminatory capacity with the area under the curve (95% confidence interval) of 0.79 (0.73 to 0.86) and specificity and sensitivity of 86% and 52%, respectively. In the out-of-sample set, the specificity of the model was 87%. The Prospective Global Registry for the Study of Chronic Total Occlusion Intervention CTO MCS score can help estimate the risk of urgent MCS use during CTO PCI.

Antegrade versus Retrograde Approach for Recanalization of Ostial or Stumpless Coronary Chronic Total Occlusion

Purpose

This research aimed to evaluate the procedural and in-hospital clinical outcomes of percutaneous coronary intervention (PCI) for ostial or stumpless chronic total occlusion (CTO) utilizing both the antegrade-only and retrograde approaches.

Methods

A comprehensive retrospective examination was conducted on the procedural and in-hospital clinical outcomes of 89 consecutive patients subjected to ostial or stumpless CTO PCI at our institution between April 2015 and October 2022.

Results

The antegrade-only technique demonstrated a superior technical success rate (92.0% vs 71.9%, p = 0.041) and procedural success rate (92.0% vs 68.8%, p = 0.022) in comparison to the retrograde approach (RA). The RA group presented a notably elevated Japanese-CTO (J-CTO) score relative to the antegrade-only approach group (2.45±0.73 vs 1.64±0.70, p < 0.001). The antegrade-only approach group manifested an increased frequency of microchannels at the proximal stump relative to the RA group (56.0% vs 10.9%, p < 0.001). In-hospital major adverse cardiac events (MACE) and in-hospital myocardial infarction (MI) were observed more prevalently in the RA group (18.8% vs 0, p = 0.003; 15.6% vs 0, p = 0.008; respectively). A J-CTO score below 2 and the manifestation of microchannels at the proximal stump were identified as predictors for successful antegrade-only approach PCI for ostial or stumpless CTO (OR: 2.79 [95% CI: 1.92-5.03, P =0.003]; OR: 2.89 [95% CI: 1.32-6.03, P =0.001]; respectively).

Conclusion

Relative to RA PCI for ostial or stumpless CTO, the antegrade-only approach is utilized for less complex CTO lesions and is associated with a diminished probability of in-hospital MACE.

Distal Target Vessel Quality and Outcomes of Chronic Total Occlusion Percutaneous Coronary Intervention

BACKGROUND

Distal vessel quality is a key parameter in the global chronic total occlusion (CTO) crossing algorithm.

OBJECTIVES

The study sought to evaluate the association of distal vessel quality with the outcomes of CTO percutaneous coronary intervention.

METHODS

We examined the clinical and angiographic characteristics and procedural outcomes of 10,028 CTO percutaneous coronary interventions performed at 39 U.S. and non-U.S. centers between 2012 and 2022. A poor-quality distal vessel was defined as <2 mm diameter or with significant diffuse atherosclerotic disease. In-hospital major adverse cardiac events (MACE) included death, myocardial infarction, urgent repeat target vessel revascularization, tamponade requiring pericardiocentesis or surgery, and stroke.

RESULTS

A total of 33% of all CTO lesions had poor-quality distal vessel. When compared with good-quality distal vessels, CTO lesions with a poor-quality distal vessel had higher J-CTO (Japanese chronic total occlusion) scores (2.7 ± 1.1 vs 2.2 ± 1.3; P < 0.01), lower technical (79.9% vs 86.9%; P < 0.01) and procedural (78.0% vs 86.8%; P < 0.01) success, and higher incidence of MACE (2.5% vs 1.7%; P < 0.01) and perforation (6.4% vs 3.7%; P < 0.01). A poor-quality distal vessel was independently associated with technical failure and MACE. Poor-quality distal vessels were associated with higher use of the retrograde approach (25.2% vs 14.9%; P < 0.01) and higher air kerma radiation dose (2.4 [IQR: 1.3-4.0] Gy vs 2.0 [IQR: 1.1-3.5] Gy; P < 0.01).

CONCLUSIONS

A poor-quality distal vessel in CTO lesions is associated with higher lesion complexity, higher need for retrograde crossing, lower technical and procedural success, higher incidence of MACE and coronary perforation, and higher radiation dose.

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.

Machine Learning for Prediction of Technical Results of Percutaneous Coronary Intervention for Chronic Total Occlusion

(1) Background: The probability of technical success in percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) represents essential information for specifying the priority of PCI for treatment selection in patients with CTO. However, the predictabilities of existing scores based on conventional regression analysis remain modest, leaving room for improvements in model discrimination. Recently, machine learning (ML) techniques have emerged as highly effective methods for prediction and decision-making in various disciplines. We therefore investigated the predictability of ML models for technical results of CTO-PCI and compared their performances to the results from existing scores, including J-CTO, CL, and CASTLE scores. (2) Methods: This analysis used data from the Japanese CTO-PCI expert registry, which enrolled 8760 consecutive patients undergoing CTO-PCI. The performance of prediction models was assessed using the area under the receiver operating curve (ROC-AUC). (3) Results: Technical success was achieved in 7990 procedures, accounting for an overall success rate of 91.2%. The best ML model, extreme gradient boosting (XGBoost), outperformed the conventional prediction scores with ROC-AUC (XGBoost 0.760 [95% confidence interval {CI}: 0.740-0.780] vs. J-CTO 0.697 [95%CI: 0.675-0.719], CL 0.662 [95%CI: 0.639-0.684], CASTLE 0.659 [95%CI: 0.636-0.681]; p < 0.005 for all). The XGBoost model demonstrated acceptable concordance between the observed and predicted probabilities of CTO-PCI failure. Calcification was the leading predictor. (4) Conclusions: ML techniques provide accurate, specific information regarding the likelihood of success in CTO-PCI, which would help select the best treatment for individual patients with CTO.

Single vs. multiple operators for chronic total occlusion percutaneous coronary interventions: From the PROGRESS-CTO Registry

BACKGROUND

There is limited data on the impact of a second attending operator on chronic total occlusion (CTO) percutaneous coronary intervention (PCI) outcomes.

METHODS

We analyzed the association between multiple operators (MOs) (>1 attending operator) and procedural outcomes of 9296 CTO PCIs performed between 2012 and 2021 at 37 centers.

RESULTS

CTO PCI was performed by a single operator (SO) in 85% of the cases and by MOs in 15%. Mean patient age was 64.4 ± 10 years and 81% were men. SO cases were more complex with higher Japan-CTO (2.38 ± 1.29 vs. 2.28 ± 1.20, p = 0.005) and Prospective Global Registry for the Study of Chronic Total Occlusion Intervention scores (1.13 ± 1.01 vs. 0.97 ± 0.93, p < 0.001) compared with MO cases. Procedural time (131 [87, 181] vs. 112 [72, 167] min, p < 0.001), fluoroscopy time (49 [31, 76] vs. 42 [25, 68] min, p < 0.001), air kerma radiation dose (2.32 vs. 2.10, p < 0.001), and contrast volume (230 vs. 210, p < 0.001) were higher in MO cases. Cases performed by MOs and SO had similar technical (86% vs. 86%, p = 0.9) and procedural success rates (84% vs. 85%, p = 0.7), as well as major adverse complication event rates (MACE 2.17% vs. 2.42%, p = 0.6). On multivariable analyses, MOs were not associated with higher technical success or lower MACE rates.

CONCLUSION

In a contemporary, multicenter registry, 15% of CTO PCI cases were performed by multiple operators. Despite being more complex, SO cases had lower procedural and fluoroscopy times, and similar technical and procedural success and risk of complications compared with MO 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.

Impact of Timing and Treatment Strategy on Coronary Perforation During Percutaneous Coronary Intervention for Chronic Total Occlusion

Coronary perforations during chronic total occlusion percutaneous coronary intervention (CTO-PCI) are potential complications and reportedly associated with adverse events. This study aimed to describe the clinical characteristics and timing of perforations during CTO-PCI. Data from the Japanese CTO-PCI expert registry included 8,760 patients who underwent CTO-PCI between January 2014 and January 2019. The major adverse cardiac and cerebrovascular events were defined as death, tamponade, myocardial infarction, stent thrombosis, stroke, and revascularization. The guidewire manipulation time was defined as the time required to cross the CTO without perforation. Among these patients, 333 (3.8%) developed perforation during the CTO crossing attempt. Of the 333 patients, 29 developed cardiac tamponades (8.7%). Perforations more frequently occurred in a retrograde wiring than in an anterograde wiring (6.6% vs 1.7%, p <0.0001). A longer guidewire manipulation time was associated with the occurrence of perforation (median 101 minutes [interquartile range 59 to 150 minutes] in the perforation group vs 54.9 minutes [interquartile range 21.1 to 112.7 minutes] in the nonperforation group, p <0.0001). Risk factors for perforation were age, history of coronary bypass graft, right coronary artery lesion, de novo lesion, use of a stiff guidewire, and guidewire manipulation time of >60 minutes during anterograde wiring and age, non-left anterior descending artery lesion, use of a polymer-jacketed guidewire, and use of epicardial channel during retrograde wiring. In conclusion, risk factors for perforation were different between anterograde and retrograde wirings. A prolonged guidewire manipulation time was associated with the occurrence of perforation, especially during anterograde wiring.

Procedural results and in-hospital outcomes of percutaneous coronary intervention for chronic total occlusion in patients with reduced left ventricular ejection fraction: Sub-analysis of the Japanese CTO-PCI Expert Registry

OBJECTIVES

To evaluate the procedural results and in-hospital outcomes of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) in patients with reduced left ventricular ejection fraction (LVEF).

BACKGROUND

While the technical success of general CTO-PCI has improved, CTO-PCI patients with reduced LVEF remain at high-risk for adverse events.

METHODS

The data of 820 patients with LVEF ≤ 35% (Group 1), 1816 patients with LVEF = 35%-50% (Group 2), and 5503 patients with LVEF ≥ 50% (Group 3), registered in the Japanese CTO-PCI Expert Registry from January 2014 to December 2019, were retrospectively analyzed. The primary endpoint was in-hospital major adverse cardiac or cerebrovascular events (MACCEs), including death, myocardial infarction, stent thrombosis, stroke, and emergent revascularization. Secondary endpoints included procedural details, guidewire success, and technical success.

RESULTS

There were no differences in guidewire and technical success rates between the groups. In-hospital MACCEs was significantly higher in Group 1 (Group 1 vs. Group 2 vs. Group 3: 3.4% vs. 1.7% vs. 1.5%, p = 0.001) and was especially driven by death (1.3% vs. 0.3% vs. 0.1%, p < 0.001) and stroke (0.7% vs. 0.2% vs. 0.2%, p = 0.007). Multivariate analysis showed that LVEF ≤ 35% (odds ratio [OR]; 1.58, 95% confidence interval [CI]; 1.04-2.41, p = 0.03) and New York Heart Association (NYHA) class ≥ 3 (OR; 2.01, 95% CI; 1.03-3.93, p = 0.04) were predictors of in-hospital MACCEs.

CONCLUSIONS

In-hospital MACCEs were significantly higher in patients with LVEF ≤ 35%. LVEF ≤;35% and NYHA class ≥ 3 were predictors of in-hospital MACCEs after CTO-PCI.

Predictors of success in primary retrograde strategy in chronic total occlusion percutaneous coronary intervention: insights from the PROGRESS-chronic total occlusion registry

BACKGROUND

An upfront (primary) retrograde strategy is often used in complex chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

METHODS

We examined the clinical, angiographic characteristics, and procedural outcomes of CTO PCIs that were approached with a primary retrograde strategy in the Prospective Global Registry for the Study of CTO Intervention (PROGRESS-CTO, NCT02061436).

RESULTS

Of 10,286 CTO PCIs performed between 2012 and 2022, a primary retrograde strategy was used in 1329 (13%) with an initial technical success of 66%, and a final success of 83%. Patients who underwent successful versus unsuccessful primary retrograde cases had similar characteristics: age (65 ± 10 vs. 65 ± 9, years, p = 0.203), men (83% vs. 87%, p = 0.066), prior PCI (71% vs. 71%, p = 0.809), and prior coronary artery bypass graft surgery (52% vs. 53%, p = 0.682). The PROGRESS-CTO score (1.3 ± 0.9 vs. 1.6 ± 0.9, p < 0.001), air kerma radiation (3.9 ± 2.8 vs. 3.4 ± 2.6, gray, p = 0.013), and contrast use (294 ± 148 ml vs. 248 ± 128, ml, p < 0.001) were higher in the unsuccessful group, whereas the presence of interventional collaterals (95% vs. 72%, p < 0.001) and Werner collateral connection grade 2 (43% vs. 31%, p < 0.001) were higher in the successful group. On multivariable logistic regression analysis, the only variable associated with a successful primary retrograde strategy was the presence of interventional collaterals: odds ratio: 6.52 (95% confidence intervals; 3.5-12.1, p < 0.001).

CONCLUSION

Presence of interventional collaterals is independently associated with higher success rates with a primary retrograde strategy in CTO PCI.

Operator experience and clinical outcomes of percutaneous coronary intervention for chronic total occlusion: insights from a pooled analysis of the Japanese CTO PCI Expert Registry and the Retrograde Summit General Registry

There have not been enough studies to examine the association between difference in operator experience and technical success rate in contemporary percutaneous coronary intervention for chronic total occlusion (CTO-PCI). The present study sought to provide insights into the impact of operator experience on clinical outcomes of CTO-PCI through a comparison of two largest Japanese CTO-PCI registries consisting of operators with different CTO-PCI experience. After combining clinical data from the Japanese CTO-PCI Expert Registry (ER) 2014-2016 (N = 4316) including CTO-PCI performed by highly experienced operators and the Retrograde Summit General Registry (RSGR) 2014-2016 (N = 2230) including CTO-PCI performed by less experienced operators, a pooled analysis was performed to compare clinical outcomes of CTO-PCI in 2 registries. The overall technical success rate and the incidence of in-hospital major adverse events were comparable between ER and RSGR (90.1% vs 88.9%, p = 0.133, 1.7% vs 1.5%, p = 0.606, respectively). Technical success rate in ER was significantly higher among the patients treated with primary antegrade approach (91.8% vs 89.5%, p = 0.009), whereas there was no significant difference among the patients treated with the primary retrograde approach (85.7% vs 85.3%, p = 0.857). Multivariate analysis suggested ER operator could not be an independent predictor for technical success. CTO-PCI performed by less experienced but appropriately trained operators could achieve similarly high technical success rate with comparable safety compared with those performed by highly experienced specialists in contemporary Japanese context.

A Case Report: Directional coronary atherectomy supported with optical coherence tomography is useful for the slit lesion

Background: Directional coronary atherectomy (DCA) was revived in Japan in 2014. DCA is a special procedure to remove the atherosclerotic plaque of coronary artery during percutaneous coronary intervention. We present the case of a 91-year-old woman with symptoms of angina. Coronary angiography revealed significant stenosis with a slit lesion of the proximal left anterior descending artery. Because she had a high risk of bleeding, we did not want to implant a stent to prevent bleeding events. Then, we performed optical coherence tomography (OCT) and intravascular ultrasound to evaluate the morphology of the slit lesion in more detail. OCT showed clearly that the direction of the flap was counterclockwise and the edge of the flap was located in the epicardium. Since we could understand the localization of plaque distribution fully by OCT examination, we successfully removed the flap by DCA based on information from OCT. After that, we performed balloon dilatation with a 3.0-mm drug-coated balloon and finished without implanting the stent successfully. Her symptoms completely disappeared and postoperative course was good.

DCA supported with OCT might be one of the options in high bleeding risk patients, suggesting a potential stent-less therapeutic option.

<Learning objective: There may be hesitation about implantation of stents in patients with high risk of bleeding, such as the elderly. Stent-less percutaneous coronary intervention using directional coronary atherectomy followed by drug-coated balloon under optical coherence tomography (OCT) guidance may be the one of the option for patients with a high risk of bleeding, because OCT can more clearly show the feature of the lesion and the effect of treatment compared to intravascular ultrasound.>

The evolution of the CTO-PCI landscape in Belgium and Luxembourg: a four-year appraisal

BACKGROUND

To chart the evolution of the CTO-PCI landscape in Belgium and Luxembourg, the Belgian Working Group on Chronic Total Occlusions (BWGCTO) was established in 2016.

METHODS

Between May 2016 and December 2019, patients undergoing a CTO-PCI treatment were prospectively and consecutively enrolled. Twenty-one centres in Belgium and one in Luxembourg participated. Individual operators had mixed levels of expertise in treating CTO lesions. Demographic, angiographic, procedural parameters and incidence of major adverse cardiac and cerebrovascular events (MACCE) were systematically registered.

RESULTS

Over a four-year enrolment period, 1832 procedures were performed in 1733 patients achieving technical success in 1474 cases (80%), with an in-hospital MACCE rate of 2.3%. Fifty-nine (3%) cases were re-attempt procedures of which 41 (69%) were successful. High-volume centres treated more complex lesions (mean J-CTO score: 2.15 ± 1.21) as compared to intermediate (mean J-CTO score: 1.72 ± 1.23; p < 0.001) and low-volume centres (mean J-CTO score: 0.99 ± 1.21; p = 0.002). Despite this, success rates did not differ between centres (p = 0.461). Overall success rates did not differ over time (p = 0.810). High-volume centres progressively tackled more complex CTOs while keeping success rates stable. In all centres, the most applied strategy was antegrade wire escalation (83%). High-volume centres more often successfully applied antegrade dissection and re-entry and retrograde techniques in lesions with higher complexity.

CONCLUSION

With variable experience levels, operators treated CTOs with high success and relatively few complications. Although AWE remains the most used technique, it is paramount for operators to be skilled in all contemporary techniques in order to be successful in more complex CTOs.

Predictors and trends of contrast use and radiation exposure in a large cohort of patients treated with percutaneous coronary interventions: Chronic total occlusion analysis based on a national registry

BACKGROUND

The aim herein, was to assess predictors and current trends of radiation exposure and total contrast amount use in patients treated with percutaneous coronary intervention within chronic total occlusion (CTO PCI) and non-CTO PCI.

METHODS

Based on a nationwide registry (ORPKI), 535,857 patients treated with PCI between 2014 and 2018 were analysed. The study included 12,572 (2.34%) patients treated with CTO PCI. The CTO PCI and non-CTO PCI groups were compared before and after propensity score matching (PSM). Multifactorial mixed regression models were used to assess predictors of contrast amount use and radiation exposure.

RESULTS

The mean total contrast dose and radiation exposure decrease reached statistical significance in following years for the CTO PCI (p = 0.002 and p < 0.001) and non-CTO PCI groups (p < 0.001 and p < 0.001). Multifactorial analysis revealed that non-CTO PCI was a strong independent predictor of lower total contrast dose (estimate: -17.41; 95% confidence interval [CI]: -18.45 to -16.49, p < 0.001) and radiation exposure (estimate: -264.28; 95% CI: -273.75 to -254.81, p < 0.001). After PSM, it was confirmed that CTO PCI was an independent predictor of greater radiation exposure (estimate: 328.6; 95% CI: 289.1-368.1; p < 0.001) and total contrast dose (estimate: 30.5; 95% CI: 27.28-33.74; p < 0.001).

CONCLUSIONS

Contrast dose and radiation exposure have decreased in previous years with regard to the CTO PCI and non-CTO PCI groups. CTO PCI was found to be an independent predictor of greater total contrast dose and radiation exposure in the overall group of patients treated with PCI.

Appropriateness of Percutaneous Coronary Intervention Performed by Japanese Expert Operators in Patients With Chronic Total Occlusion

BACKGROUND

The appropriateness of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) lesions has rarely been investigated.Methods and Results:The Japanese CTO-PCI Expert Registry enrolled consecutive patients undergoing CTO-PCI carried out by highly experienced Japanese CTO specialists who performed more than 50 CTO-PCIs per year and 300 CTO-PCIs in total. This study included patients undergoing CTO-PCI between January 2014 and December 2019. The appropriateness, trends, and differences among the procedures performed by the operators using the 2017 appropriate use criteria were analyzed. Furthermore, we performed a logistic regression analysis to assess whether the appropriateness was associated with in-hospital major adverse cardiovascular and cerebrovascular events (MACCE). Of the 5,062 patients who underwent CTO-PCI, 4,309 (85.1%) patients who did not undergo the non-invasive stress test were classified as having no myocardial ischemia. Of the total cases, 3,150 (62.2%) were rated as "may be appropriate," and 642 (12.7%) as "rarely appropriate" CTO-PCI cases. The sensitivity analyses showed that the number (%) of "may be appropriate" ranged from 4,125 (57.8%) to 4,744 (66.4%) and the number of "rarely appropriate" ranged from 843 (11.8%) to 970 (13.6%) among best and worst scenarios.

CONCLUSIONS

In a large Japanese CTO-PCI registry, approximately 13% of CTO-PCI procedures were classified as "rarely appropriate". Substantial efforts would be required to decrease the number of "rarely appropriate" CTO-PCI procedures.

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.

Occlusion patterns, strategies and procedural outcomes of percutaneous coronary intervention for in-stent chronic total occlusion

BACKGROUND

In-stent chronic total occlusion (CTO) presents various occlusion patterns, which complicate percutaneous coronary intervention (PCI).

AIMS

The aim of the study was to investigate the initial outcome and strategy of PCI for in-stent CTO according to the angiographic occlusion patterns.

METHODS

This study assessed 791 in-stent CTOs from the Japanese CTO-PCI Expert Registry from 2015 to 2018. They were divided into four patterns: pattern A (n=419), CTO within the stent segment; pattern B (n=196), CTO beyond the distal edge; pattern C (n=85), CTO beyond the proximal edge; and pattern D (n=69) CTO beyond both the proximal and distal edges.

RESULTS

There were significant differences in the technical success rates (96.2%, 86.2%, 92.9%, and 75.4% for patterns A-D, respectively; p<0.001), guidewire crossing times (22 [interquartile range: 10-46], 52 [24-102], 40 [20-78], and 86 [45-127] min, respectively; p<0.001), and the rates of antegrade approach alone (90.9%, 61.2%, 67.1%, and 31.9%, respectively; p<0.001).

CONCLUSIONS

PCI for CTO within the stent segment was associated with excellent initial outcomes with the antegrade approach. However, PCI for CTO beyond both the proximal and distal edges was associated with the poorest outcomes, even with the bidirectional approach.

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.

Tunnelling a calcified total occlusion

Among the complex and high-risk coronary intervention cases, a calcified total occlusion of coronary artery poses a great challenge. We came across a 48 years old male who had calcified total occlusion of the right coronary artery. The chronic total occlusion was crossed using Nic-Nano balloon and the calcific plaque was modified using intravascular lithotripsy as an alternative technique to rotational atherectomy which we felt as an evolving alternative approach to treat the calcified total occlusion.

Complications during chronic total occlusion percutaneous coronary intervention: a sign- and symptom-based approach to early diagnosis and treatment

Coronary chronic total occlusions (CTO) are frequently found in patients undergoing coronary angiography. Despite their high prevalence and indication for revascularization in a relevant proportion of cases, CTO recanalization is attempted only in a minority of cases. This is due to higher risk of procedural complications compared to non-CTO interventions and because the CTO-PCIs are the most complex procedures in interventional cardiology. In particular, the perceived higher risk of complications during CTO intervention might discourage new operators from engaging in this challenging field. The aim of this work is to review the potential complications of CTO percutaneous coronary intervention, and to provide an algorithmic, sign- and symptom-based approach to facilitate early recognition and effective management.

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

OBJECTIVES

This study aimed to identify the predictive factors for the guidewire manipulation time (GWMT) of ≥20 and 30 min for chronic total occlusion-percutaneous coronary intervention (CTO-PCI) via the primary antegrade approach (PAA).

BACKGROUND

Selection of primary retrograde approach (PRA) and the optimal timing to switch from antegrade to retrograde approach for coronary CTO-PCI is still debatable.

METHODS

Using the Japanese CTO-PCI expert registry data, we selected and analyzed 4461 patients who underwent CTO-PCI via PAA alone. The considerable lesion/anatomical factors for GWMT ≥20 and 30 min were analyzed. The risks of prolonged GWMT ≥20 and 30 min were stratified as easy, intermediate, difficult, and very difficult according to the multivariate analysis.

RESULTS

Nine lesion/anatomical characteristics (blunt stump, side branch at proximal cap, bifurcation at the exit point, calcification, tortuosity, occlusion length ≥ 20 mm, reattempt, nonleft anterior descending artery (nonleft anterior descending artery [LAD]), and tandem CTO) were independent predictors of GWMT ≥20 min (all p < 0.05). Excluding the nonLAD and tandem CTO, the same factors of GWMT ≥20 min correlated with GWMT ≥30 min (all p < 0.05). The distributions were increased in easy, intermediate, difficult, and very difficult subsets of GWMT ≥20 min (58.3%, 77.2%, 89.1%, and 100%) and GWMT ≥30 min (47.5%, 69.2%, 83.9%, and 100%).

CONCLUSIONS

These predictive factors of prolonged GWMT should be assessed before CTO-PCI via PAA and when considering an adequate timing to switch the retrograde or PRA if clinically available.

Effect of Coronary CTA on Chronic Total Occlusion Percutaneous Coronary Intervention: A Randomized Trial

OBJECTIVES

The purpose of this study was to test whether the success rate of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) increased with pre-procedural coronary computed tomography angiography (CTA).

BACKGROUND

Coronary CTA provides valuable information before and during CTO-PCI. However, there are no randomized data that explore whether coronary CTA increases its success rate.

METHODS

In this multicenter, randomized trial, a total of 400 patients with CTO were randomized to receive PCI with pre-procedural coronary CTA (coronary CTA-guided group; n = 200) or without coronary CTA (angiography-guided group; n = 200) between January 2014 and September 2019. The primary endpoint was the successful recanalization rate, a final TIMI (Thrombolysis In Myocardial Infarction) grade ≥2, and ≤30% residual stenosis on the final angiogram.

RESULTS

A total of 10 operators performed PCI. Successful recanalization was achieved in 187 patients (93.5%) in the coronary CTA-guided group and in 168 patients (84.0%) in the angiography-guided group (absolute difference, 9.5% [95% confidence interval: 3.4% to 15.6%]; p = 0.003). When comparing the success rates according to the Multicenter CTO Registry of Japan score (J-CTO), the coronary CTA guidance was favored over the angiography-guidance in the subset of J-CTO ≥2 versus in the subset of J-CTO <2 (p interaction = 0.035). Coronary perforations occurred in 2 (1%) and 8 patients (4%) in the coronary CTA- and angiography-guided groups, respectively (p = 0.055). Periprocedural myocardial infarction was not observed in the coronary CTA-guided group, whereas it occurred in 4 patients (2%) in the angiography-guided group (p = 0.123). Total procedure and fluoroscopic times were not different. There were no differences between the groups in the occurrences of cardiac death, target vessel-related myocardial infarction, or target-vessel revascularization at 1 year.

CONCLUSIONS

Pre-procedural coronary CTA-guidance for CTO resulted in higher success rates with numerically fewer immediate periprocedural complications such as coronary perforations or periprocedural myocardial infarction than angiography guidance. Higher success rates were more prominently observed in patients with CTO who had a high J-CTO score than those who did not. (Role of CT Scan for the Successful Recanalization of Chronic Total Occlusion; a Randomized Comparison Between 3D CT-guided PCI vs. Conventional Treatment [CT-CTO Trial]; NCT02037698).

A prospective study on the incidence of contrast-associated acute kidney injury after recanalization of chronic total coronary occlusions with contemporary interventional techniques

BACKGROUND

Contrast-associated acute kidney injury (CA-AKI) is a potential risk associated with the percutaneous coronary interventions (PCI) for chronic total coronary occlusions (CTO). This study should evaluate the incidence of CA-AKI in an era of advanced strategies of recanalization techniques and identify modifiable determinants.

METHODS

We analysed 1924 consecutive CTO procedures in 1815 patients between 2012 and 2019. All patients were carefully monitored at least up to 48 h after a CTO procedure for changes in renal function.

RESULTS

The incidence of CA-AKI was 5.6%, but there was no relation to the technical approach such as frequency of the retrograde technique, intravascular ultrasound or radial access. Procedures with CA-AKI had longer fluoroscopy times (37.6 vs 46.1 min; p = 0.005). The major determinants of CA-AKI were age, presence of diabetes and reduced ejection fraction, as well as chronic kidney disease stage ≥2, serum haemoglobin, and fluoroscopy time. Contrast volume or contrast volume/GFR ratio were not independent determinants of CA-AKI. Periprocedural perforations were more frequent in CA-AKI patients (11.3 vs 2.3%; p < 0.001), and in-hospital mortality was higher (2.8 vs 0.4%; p < 0.001).

CONCLUSIONS

CA-AKI was associated with the risk of in-hospital adverse events. Established patient-related risk factors for CA-AKI (age, diabetes, preexisting chronic kidney disease, low ejection fraction) were confirmed in this study. In addition, the length of the procedure, coronary perforations and low preprocedural serum haemoglobin were risk factors that might be preventable in patients at high risk for CA-AKI.

Outcomes of retrograde chronic total occlusion percutaneous coronary intervention: A report from the OPEN-CTO registry

OBJECTIVES

We sought to assess in-hospital and long-term outcomes of retrograde compared with antegrade-only percutaneous coronary intervention for chronic total occlusion (CTO PCI).

BACKGROUND

Procedural and clinical outcomes following retrograde compared with antegrade-only CTO PCI remain unknown.

METHODS

Using the core-lab adjudicated OPEN-CTO registry, we compared the outcomes of retrograde to antegrade-only CTO PCI. Primary endpoints included were in-hospital major adverse cardiac and cerebrovascular events (MACCE) (all-cause death, stroke, myocardial infarction [MI], emergency cardiac surgery, or clinically significant perforation) and MACCE at 1-year (all-cause death, MI, stroke, target lesion revascularization, or target vessel reocclusion).

RESULTS

Among 885 single CTO procedures from the OPEN-CTO registry, 454 were retrograde and 431 were antegrade-only. Lesion complexity was higher (J-CTO score: 2.7 vs. 1.9; p < .001) and technical success lower (82.4 vs. 94.2%; p < .001) in retrograde compared with antegrade-only procedures. All-cause death was higher in the retrograde group in-hospital (2 vs. 0%; p = .003), but not at 1-year (4.9 vs. 3.3%; p = .29). Compared with antegrade-only procedures, in-hospital MACCE rates (composite of all-cause death, stroke, MI, emergency cardiac surgery, and clinically significant perforation) were higher in the retrograde group (10.8 vs. 3.3%; p < .001) and at 1-year (19.5 vs. 13.9%; p = .03). In sensitivity analyses landmarked at discharge, there was no difference in MACCE rates at 1 year following retrograde versus antegrade-only CTO PCI. Improvements in Seattle Angina Questionnaire Quality of Life scores at 1-year were similar between the retrograde and antegrade-only groups (29.9 vs 30.4; p = .58).

CONCLUSIONS

In the OPEN-CTO registry, retrograde CTO procedures were associated with higher rates of in-hospital MACCE compared with antegrade-only; however, post-discharge outcomes, including quality of life improvements, were similar between technical modalities.

Current challenges and prevention strategies for chronic total occlusion (CTO) complications

Introduction: Percutaneous coronary intervention (PCI) of chronic total occlusion (CTO) can be challenging, but high success rates (85-90%) are currently achieved at experienced centers with approximately 3% risk for a major periprocedural complication.Areas covered: CTO PCI complications can be categorized according to location such as cardiac and non-cardiac (vascular access complications, thromboembolic complications, contrast-related and radiation injury) complications. Cardiac complications are further subdivided into coronary (acute closure, perforation, and equipment loss or entrapment) and non-coronary (hypotension, myocardial infarction, tamponade, arrhythmias).Expert opinion: In this article, we review strategies to prevent and treat CTO PCI complications. Careful monitoring throughout the case enables prevention and early detection of a complication. If a complication occurs, rapid implementation of treatment using an algorithmic approach can minimize its adverse impact.

Reattempt Percutaneous Coronary Intervention of Chronic Total Occlusions after Prior Failures: A Single-Center Analysis of Strategies and Outcomes

OBJECTIVE

The initial recanalization rate of coronary chronic total occlusions (CTOs) is >85% when performed by experienced operators, but only 10% of prior failed CTO patients receive reattempted recanalization. This retrospective study analyzed the success rate and strategies used in reattempt percutaneous coronary intervention (PCI) of CTOs after prior failures.

METHODS

Overall, 206 patients with 212 CTOs were enrolled. All patients with prior recanalization failures received reattempt PCIs from January 2015 to March 2019 at Zhongshan Hospital, Fudan University. Data on clinical factors (age, sex, comorbidities, left ventricular ejection fraction, history of cigarette usage, and revascularization), angiographic characteristics of CTOs (target lesion, Japanese Chronic Total Occlusion (J-CTO) score, the morphology of CTO lesions, and collateral channel scale), strategies (procedural approach and use of devices), and major adverse events were obtained and analyzed.

RESULTS

The mean age of enrolled patients was 60.96 ± 12.36 years, with a male predominance of 90.3%. Of the patients, 47.1% had a prior myocardial infarction and 70.4% underwent stent implantation previously, while the in-stent occlusion rate was 6.6%. CTOs were primarily localized in the left anterior descending artery (43.9%) and the right coronary artery (43.9%). 80.7% of lesions were classified as very difficult (J-CTO score ≥3), and the overall success rate was 81.1%. In multivariable regression analysis, J-CTO score, collateral channel scale, application of coronary multispiral computed tomography angiography, dual injection, intravascular ultrasound, active greeting technique, parallel wiring, and CTO morphology were predictors of recanalization success. There were no significant differences in rates of procedural complications between the final recanalization success and failure groups.

CONCLUSIONS

Recanalization of complex CTOs is associated with high success rate and low complication rates when performed by high-volume CTO operators and after multiple reattempts.

Real world perspective of coronary chronic total occlusion in third world countries: A tertiary care centre study from northern India

OBJECTIVES

The aim of this study is to determine the prevalence, clinical characteristics, angiographic profile and predictors of outcome for percutaneous coronary interventions (PCI) of coronary chronic total occlusions (CTO) in a tertiary referral centre of north India.

BACKGROUND

There is no data on the prevalence and very few reports on clinical characteristics, angiographic profile and outcome of PCI in CTO from India.

METHODS

Retrospective analysis was done for the data of 12,020 patients undergoing coronary angiography (CAG) between January 2018 to January 2019 at our centre. Detailed baseline clinical, angiographic and revascularization data was collected. Outcome of CTO PCI was also noted. All baseline parameters were analysed for predicting the outcome of CTO PCI.

RESULTS

CTO was identified in 16.3% (1968) patients undergoing CAG and in 24.4% of patients with hemodynamically significant CAD. CTO was predominantly found in LAD (48%) followed by RCA (42.9%) and LCx (25.3%) arterial distribution. Mean JCTO score was 1.93 ± 0.7. PCI as a management strategy was adopted in 456 of 1968 patients (23.1%) and was successful in 340 of 456 (74.6%) of patients. Almost all CTO PCI were attempted by an antegrade approach only. Increasing age, male sex, CTO in LCx arterial distribution and higher J CTO score were associated with poorer outcome in CTO PCI.

CONCLUSIONS

CTO's are commonly encountered during CAG procedures. In patients undergoing CTO PCI, a fair success rate can be achieved in a high volume experienced centre.

Clinical Factors Associated with Long Fluoroscopy Time in Percutaneous Coronary Interventions to the Culprit Lesion of Non-ST-Segment Elevation Myocardial Infarction

The clinical outcomes of patients with non-ST-segment elevation myocardial infarction (NSTEMI) were comparable or even worse than those with ST-segment elevation myocardial infarction (STEMI). Although successful percutaneous coronary intervention (PCI) to the culprit lesions of NSTEMI would improve the clinical outcomes, some PCI require long fluoroscopy time, reflecting the difficulty of PCI. This study aims to find clinical factors associated with long fluoroscopy time in PCI to the culprit lesion of NSTEMI. We included 374 patients and divided those into the conventional fluoroscopy time (n = 302) and long fluoroscopy time (n = 72) groups according to the quintiles of fluoroscopy time. Clinical and angiographic parameters were compared between the two groups. Calcification and tortuosity were significantly more severe in the long fluoroscopy time group than in the conventional fluoroscopy time group. The prevalence of previous coronary artery bypass grafting (CABG) and bifurcation lesions was significantly greater in the long fluoroscopy time group than in the conventional fluoroscopy time group. In the multivariate stepwise logistic regression analysis, previous CABG (odds ratio [OR], 3.368; 95% confidence interval [CI], 1.407-8.064; P = 0.006), bifurcation lesion (OR, 2.407; 95% CI, 1.285-4.506; P = 0.006), excessive tortuosity (versus mild to moderate tortuosity; OR, 4.095; 95% CI, 1.159-14.476; P = 0.029), and moderate to severe calcification (versus none to mild; OR, 5.792; 95% CI, 3.254-10.310; P < 0.001) were significantly associated with long fluoroscopy time. In conclusion, previous CABG, bifurcation, excessive tortuosity, and moderate to severe calcification were associated with long fluoroscopy time. Our study provided a reference for PCI operators to identify the difficulties in PCI to the culprit lesion of NSTEMI.

Chronic total occlusion percutaneous coronary intervention in everyday clinical practice - an expert opinion of the Association of Cardiovascular Interventions of the Polish Cardiac Society

Coronary chronic total occlusions (CTO) are increasingly encountered during invasive and non-invasive coronary angiography and remain the most challenging lesions for percutaneous revascularization. During recent years success rates and safety outcomes of CTO percutaneous coronary intervention (PCI) have substantially improved, particularly due to the introduction of new techniques and dedicated equipment as well as specialized training programs of CTO operators. Significantly, the steady advances in CTO PCI techniques have coincided with the new data from randomized clinical trials supporting the role of percutaneous recanalization of CTO in relieving angina and improving the quality of life. The current expert consensus document outlines the rationale, clinical outcomes as well as technical, safety and reimbursement issues of CTO PCI. In addition, the requirements for achieving and maintaining competency in CTO PCI among interventional cardiologists are discussed. Finally, we present the modified hybrid algorithm (the so-called Polish hybrid algorithm) providing some unique refinements to the contemporary CTO PCI strategies. Continuous efforts (including active engagement with the payer) are urgently needed to increase guideline-recommended referrals to CTO PCI, and thus improve the quality of life of CTO patients in Poland.

Revascularization of Coronary Artery Chronic Total Occlusion by Active Antegrade Reverse Wire Technique

Objectives

To assess the effectiveness and safety of ARW for vascular recanalization in CTO patients.

Background

Chronic total occlusion (CTO) of coronary artery accompanied with large branch distal to the occluded segment (<2 mm) is one of the challenges physicians are facing during the coronary intervention. In cases where the antegrade wire passed the occluded segment reaching the branch vessel, but could not access the main vessel through various adjustments, application of active antegrade reverse wire technique (ARW) could be considered. Patients and Methods. A total of 301 consecutive CTO patients who received the antegrade percutaneous coronary intervention (PCI) between December 2015 and December 2019 at our institution were included, of whom 11 were treated with ARW (10 successfully) for vascular recanalization. The applicability and safety of ARW were assessed.

Results

Among the 301 CTO patients who received antegrade vascular recanalization, 11 were treated with ARW. ARW was successful in 10 patients as follows: from the diagonal branch (D) to anterior descending branch (LAD) in 4 patients; from the septal branch (S) to LAD in 1 patient; from D to S and LAD in 1 patient; from the circumflex branch (LCX) to obtuse marginal branch (OM) in 1 patient; from OM to LCX in 1 patient; from a posterior descending artery (PDA) to the posterior lateral vein (PLV) in 2 patients. Yet, ARW in patient with RCAm CTO failed, while the consequent retrograde PCI succeeded. The mean J-CTO score of the 11 patients was 2.7 ± 0.65, among whom eight were accompanied with calcifications. Sion Black and Fielder XTR reverse wires were used in 9 and 2 patients, respectively. No loss of side branches or severe procedure-related complications occurred in 11 patients.

Conclusion

Therefore, ARW can improve procedural efficiency and should be popularized for further application.