Wire-based antegrade dissection re-entry technique for coronary chronic total occlusions percutaneous revascularization: Experience from the ERCTO Registry.

BACKGROUND: The recent development and widespread adoption of antegrade dissection re-entry (ADR) techniques have been underlined as one of the antegrade strategies in all worldwide CTO consensus documents. However, historical wire-based ADR experience has suffered from disappointing long-term outcomes. AIMS: Compare technical success, procedural success, and long-term outcome of patients who underwent wire-based ADR technique versus antegrade wiring (AW). METHODS: One thousand seven hundred and ten patients, from the prospective European Registry of Chronic Total Occlusions (ERCTO), underwent 1806 CTO procedures between January 2018 and December 2021, at 13 high-volume ADR centers. Among all 1806 lesions attempted by the antegrade approach, 72% were approached with AW techniques and 28% with wire-based ADR techniques. RESULTS: Technical and procedural success rates were lower in wire-based ADR than in AW (90.3% vs. 96.4%, p < 0.001; 87.7% vs. 95.4%, p < 0.001, respectively); however, wire-based ADR was used successfully more often in complex lesions as compared to AW (p = 0.017). Wire-based ADR was used in most cases (85%) after failure of AW or retrograde procedures. At a mean clinical follow-up of 21 ± 15 months, major adverse cardiac and cerebrovascular events (MACCEs) did not differ between AW and wire-based ADR (12% vs. 15.1%, p = 0.106); both AW and wire-based ADR procedures were associated with significant symptom improvements. CONCLUSIONS: As compared to AW, wire-based ADR is a reliable and effective strategy successfully used in more complex lesions and often after the failure of other techniques. At long-term follow-up, patient's MACCEs and symptoms improvement were similar in both antegrade techniques.

Use of the Carlino Technique in Chronic Total Occlusion Percutaneous Coronary Intervention.

We examined the outcomes of the Carlino technique in chronic total occlusion (CTO) percutaneous coronary interventions (PCIs). We analyzed the baseline clinical and angiographic characteristics and outcomes of 128 CTO PCIs that included the Carlino technique at 22 US and no-US centers between 2016 and 2023. The Carlino technique was used in 128 (2.8%) of 4,508 cases that used anterograde dissection and reentry (78.9%) or the retrograde approach (21.1%) during the study period, and it increased steadily over time (from 0.0% in 2016 to 8.3% in 2023). The mean patient age was 65.6 ± 9.7 years, and 88.7% of the patients were men with high prevalence of hypertension (89.1%) and dyslipidemia (80.2%). The Carlino technique was more commonly used in cases with moderate to severe calcification (77.2% vs 55.5%, p <0.001) with higher J-CTO (3.3 ± 0.9 vs 3.0 ± 1.1, p = 0.007), Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS-CTO) (1.7 ± 1.0 vs 1.4 ± 1.0, p = 0.001), PROGRESS-CTO Mortality (2.6 ± 0.9 vs 2.0 ± 0.9, p = 0.013) and PROGRESS-CTO Perforation (3.7 ± 1.1 vs 3.5 ± 1.0, p = 0.029) scores. Carlino cases had longer procedure and fluoroscopy time, and higher contrast volume and radiation dose. Carlino cases had lower technical (65.6% vs 78.5%, p <0.001) and procedural (63.3% vs 76.3%, p <0.001) success, similar major adverse cardiac events (6.2% vs 3.2%, p = 0.101) and higher incidence of pericardiocentesis (3.9% vs 1.3%, p = 0.042), perforation (18.0% vs 8.9%, p = 0.001) and contrast-induced acute kidney injury (2.3% vs 0.4%, p = 0.012). The Carlino technique was associated with higher procedural success when used for retrograde crossing (81.5% vs 58.4%, p = 0.047). The Carlino technique is increasingly being used in CTO PCI especially for higher complexity lesions.

STAR procedure becomes SAFER: First-in-man case series of a new antegrade dissection re-entry technique.

INTRODUCTION: Antegrade dissection and re-entry (ADR) is an integral part of the hybrid algorithm, which has allowed for improved outcomes in chronic total occlusion (CTO) coronary intervention (PCI). METHODS: A new ADR method, Subintimal Antegrade FEnestration and Re-entry (SAFER), is described. The results of a first-in-man series are presented. RESULTS: SAFER was performed on seven consecutive patients with angiographic and clinical success in all patients. CONCLUSIONS: This first-in-man study has shown that the SAFER technique is feasible and effective with the possibility of improving the antegrade PCI CTO success rate.

Gender differences in percutaneous coronary intervention for chronic total occlusions from the ERCTO study.

BACKGROUND: Gender-specific data addressing percutaneous coronary intervention (PCI) of chronic total occlusion (CTO) in female patients are scarce and based on small sample size studies. AIMS: We aimed to analyze gender-differences regarding in-hospital clinical outcomes after CTO-PCI. METHODS: Data from 35,449 patients enrolled in the prospective European Registry of CTOs were analyzed. The primary outcome was the comparison of procedural success rate in the two cohorts (women vs. men), defined as a final residual stenosis less than 20%, with Thrombolysis In Myocardial Infarction grade flow = 3. In-hospital major adverse cardiac and cerebrovascular events (MACCEs) and procedural complications were deemed secondary outcomes. RESULTS: Women represented 15.2% of the entire study population. They were older and more likely to have hypertension, diabetes, and renal failure, with an overall lower J-CTO score. Women showed a higher procedural success rate (adjusted OR [aOR] = 1.115, confidence interval [CI]: 1.011-1.230, p = 0.030). Apart from previous myocardial infarction and surgical revascularization, no other significant gender differences were found among predictors of procedural success. Antegrade approach with true-to-true lumen techniques was more commonly used than retrograde approach in females. No gender differences were found regarding in-hospital MACCEs (0.9% vs. 0.9%, p = 0.766), although a higher rate of procedural complications was observed in women, such as coronary perforation (3.7% vs. 2.9%, p < 0.001) and vascular complications (1.0% vs. 0.6%, p < 0.001). CONCLUSIONS: Women are understudied in contemporary CTO-PCI practice. Female sex is associated with higher procedural success after CTO-PCI, yet no sex differences were found in terms of in-hospital MACCEs. Female sex was associated with a higher rate of procedural complications.

Role of the retrograde Carlino technique for chronic total occlusion percutaneous coronary intervention.

BACKGROUND: There is scarce data on the outcomes of the Carlino technique for chronic total occlusion (CTO) percutaneous coronary intervention (PCI). We aimed to investigate the indications and outcomes of the Carlino technique as performed in the context of the retrograde approach. METHODS: We pooled CTO PCI cases where a retrograde Carlino technique was performed from high-volume operators at four centers. The Carlino technique was characterized according to its indication (achieving plaque/cap modification, clarifying microcatheter location within the vessel, resolving distal cap ambiguity) and was considered successful when it led to the desired outcome. RESULTS: A total of 43 patients were included. Occlusion complexity was very high (mean J-CTO score 3.3 ± 0.8). The two most common indications were understanding the anatomy of the occlusion and clarifying gear location (37.2%) and impenetrable distal cap (34.9%). The Carlino technique was successful in 88.4% of cases. Overall technical and procedural success was 86.0%. The most common successful crossing technique was reverse controlled antegrade and retrograde subintimal tracking (70.3%). No complications were attributed to the Carlino technique. CONCLUSIONS: We observed a high success rate of the retrograde Carlino technique, as well as overall technical and procedural success rates. No Carlino technique-related complications were observed. Additional data from larger registries are warranted to further confirm the safety and efficacy of this technique.

External validation of the PROGRESS-CTO perforation risk score: Individual patient data pooled analysis of three registries.

BACKGROUND: Coronary artery perforation is one of the most feared and common complications of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). METHODS: To assess the usefulness of the recently developed PROGRESS-CTO (NCT02061436) perforation risk score in independent cohorts. Individual patient-level data pooled analysis of three registries was performed. RESULTS: Of the 4566 patients who underwent CTO PCI at 25 centers, 196 (4.2%) had coronary artery perforation. Patients with perforations were older (69 ± 10 vs. 65 ± 10, p < 0.001), more likely to be women (19% vs. 13%, p = 0.009), more likely to have a history of prior coronary artery bypass graft (34% vs. 20%, p < 0.001), and unfavorable angiographic characteristics such as blunt stump (62% vs. 48%, p < 0.001), proximal cap ambiguity (52% vs. 34%, p < 0.001), and moderate-severe calcification (60% vs. 49%, p = 0.002). Technical success was lower in patients with perforations (73% vs. 88%, p < 0.001). The area under the receiver operating characteristic curve of the PROGRESS-CTO perforation risk model was 0.76 (95% confidence interval [CI], 0.72-0.79), with good calibration (Hosmer-Lemeshow p = 0.97). We found that the CTO PCI perforation risk increased with higher PROGRESS-CTO perforation scores: 0.3% (score 0), 2.3% (score 1), 3.1% (score 2), 5.5% (score 3), 7.5% (score 4), 14.6% (score 5). CONCLUSION: Given the good discriminative performance, calibration, and the ease of calculation, the PROGRESS-CTO perforation score may facilitate assessment of the risk of perforation in patients undergoing CTO PCI.

Validation of the OPEN-CLEAN Chronic Total Occlusion Percutaneous Coronary Intervention Perforation Score in a Multicenter Registry.

Coronary artery perforation is one of the most common and feared complications of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). We evaluated the utility of the recently presented OPEN-CLEAN (Coronary artery bypass graft, Length of occlusion, Ejection fraction, Age, calcificatioN) perforation score in an independent multicenter CTO PCI dataset. Of the 2,270 patients who underwent CTO PCI at 7 centers, 150 (6.6%) suffered coronary artery perforation. Patients with perforations were older (69 ± 10 vs 65 ± 10, p <0.001), more likely to be women (89% vs 82%, p = 0.010), more likely to have history of previous coronary artery bypass graft (38% vs 20%, p <0.001), and unfavorable angiographic characteristics such as blunt stump (64% vs 42%, p <0.001), proximal cap ambiguity (51% vs 33%, p <0.001), and moderate-severe calcification (57% vs 43%, p = 0.001). Technical success was lower in patients with perforations (69% vs 85%, p <0.001). The area under the receiver operating characteristic curve of the OPEN-CLEAN perforation risk model was 0.74 (95% confidence interval 0.68 to 0.79), with good calibration (Hosmer-Lemeshow p = 0.72). We found that the CTO PCI perforation risk increased with higher OPEN-CLEAN scores: 3.5% (score 0 to 1), 3.1% (score 2), 5.3% (score 3), 7.1% (score 4), 11.5% (score 5), 19.8% (score 6 to 7). In conclusion, given its good performance and ease of preprocedural calculation, the OPEN-CLEAN perforation score appears to be useful for quantifying the perforation risk for patients who underwent CTO PCI.

External validation of the PROGRESS-CTO complication risk scores: Individual patient data pooled analysis of 3 registries.

BACKGROUND: Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) is associated with a considerable risk of complications, and risk stratification is of utmost importance. AIMS: To assess the clinical usefulness of the recently developed PROGRESS-CTO (NCT02061436) complication risk scores in an independent cohort. METHODS: Individual patient data pooled analysis of 3 registries was performed. RESULTS: Of the 4569 patients who underwent CTO PCI, 102 (2.2%) had major adverse cardiovascular events (MACE). Patients with MACE were older (69 ± 11 vs. 65 ± 10, p < 0.001), more likely to have a history of prior coronary artery bypass graft surgery, and unfavorable angiographic characteristics J-CTO score (2.4 ± 1.2 vs. 2.1 ± 1.3, p = 0.007), including blunt stump (59% vs. 49%, p = 0.047). Technical success was lower in patients with MACE (59% vs. 86%, p < 0.001). The area under the receiver operating characteristic curve of the PROGRESS-CTO complication risk models were as follows: MACE 0.72 (95% confidence interval [CI], 0.67-0.76), mortality 0.73 (95% CI, 0.61-0.85), and pericardiocentesis 0.69 (95% CI, 0.62-0.77) in the validation dataset. The observed complication rates increased with higher PROGRESS-CTO complication scores. The PROGRESS-CTO MACE score showed good calibration in this external cohort, with MACE rates similar to the original study: 0.7% (score 0-1), 1.5% (score 2), 2.2% (score 3), 3.8% (score 4), 4.9% (score 5), 5.8% (score 6-7). CONCLUSION: Given the good discriminative performance, calibration, and ease of calculation, the PROGRESS-CTO complication scores could help assess the risk of complications in patients undergoing CTO PCI.

The origin of the popular iconic heart symbol: fiction or facts?

The heart is generally perceived as the core of emotion, affection, and love. Its universally accepted iconic representation is everywhere these sentiments have to be depicted. However, the question is: where does the popular heart shape comes from? In fact, it is difficult to relate this symbol to the real heart shape. With possible early examples or direct predecessors in the 13th to 14th century, the familiar symbol of the heart representing love developed in the 15th century, and became popular in Europe during the 16th. While performing several coronary total occlusion recanalization procedures, it has become excitingly evident that, during contemporaneous dual injections of both right and left coronary arteries, the iconic shadow of the heart can be effectively observed. The possibility that the evidence of this cardiac shape could already be visible to the eyes of people living at the time of the first iconic appearances of the heart image is difficult to surmise. How could our ancestors connect the iconic form to the real heart shape? In the present article, we discuss how this iconic shape could have been derived from anatomical observations made in the ancient world.

Contemporary Issues in Chronic Total Occlusion Percutaneous Coronary Intervention.

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

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

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

In-Stent CTO Percutaneous Coronary Intervention: Individual Patient Data Pooled Analysis of 4 Multicenter Registries.

OBJECTIVES: The authors sought to examine the outcomes of percutaneous coronary intervention (PCI) for in-stent restenosis (ISR) chronic total occlusions (CTOs). BACKGROUND: The outcomes of PCI for ISR CTOs have received limited study. METHODS: The authors examined the clinical and angiographic characteristics and procedural outcomes of 11,961 CTO PCIs performed in 11,728 patients at 107 centers in Europe, North America, Latin America, and Asia between 2012 and 2020, pooling patient-level data from 4 multicenter registries. In-hospital major adverse cardiovascular events (MACE) included death, myocardial infarction, stroke, and tamponade. Long-term MACE were defined as the composite of all-cause death, myocardial infarction, and target vessel revascularization. RESULTS: ISR represented 15% of the CTOs (n = 1,755). Patients with ISR CTOs had higher prevalence of diabetes (44% vs. 38%; p < 0.0001) and prior coronary artery bypass graft surgery (27% vs. 24%; p = 0.03). Mean J-CTO (Multicenter CTO Registry in Japan) score was 2.32 ± 1.27 in the ISR group and 2.22 ± 1.27 in the de novo group (p = 0.01). Technical (85% vs. 85%; p = 0.75) and procedural (84% vs. 84%; p = 0.82) success was similar for ISR and de novo CTOs, as was the incidence of in-hospital MACE (1.7% vs. 2.2%; p = 0.25). Antegrade wiring was the most common successful strategy, in 70% of ISR and 60% of de novo CTOs, followed by retrograde crossing (16% vs. 23%) and antegrade dissection and re-entry (15% vs. 16%; p < 0.0001). At 12 months, patients with ISR CTOs had a higher incidence of MACE (hazard ratio: 1.31; 95% confidence interval: 1.01 to 1.70; p = 0.04). CONCLUSIONS: ISR CTOs represent 15% of all CTO PCIs and can be recanalized with similar success and in-hospital MACE as de novo CTOs.

Intravascular Ultrasound-Guided Coronary Lithotripsy Treatment of In-Stent Restenosis in Saphenous Venous Graft.

To the best of our knowledge, this is the first description of intravascular-ultrasound guided coronary lithotripsy on saphenous vein graft because of severely calcific in-stent restenosis, showing good result without procedural complications.

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

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

Definitions and Clinical Trial Design Principles for Coronary Artery Chronic Total Occlusion Therapies: CTO-ARC Consensus Recommendations.

Over the past 2 decades, chronic total occlusion (CTO) percutaneous coronary intervention has developed into its own subspecialty of interventional cardiology. Dedicated terminology, techniques, devices, courses, and training programs have enabled progressive advancements. However, only a few randomized trials have been performed to evaluate the safety and efficacy of CTO percutaneous coronary intervention. Moreover, several published observational studies have shown conflicting data. Part of the paucity of clinical data stems from the fact that prior studies have been suboptimally designed and performed. The absence of standardized end points and the discrepancy in definitions also prevent consistency and uniform interpretability of reported results in CTO intervention. To standardize the field, we therefore assembled a broad consortium comprising academicians, practicing physicians, researchers, medical society representatives, and regulators (US Food and Drug Administration) to develop methods, end points, biomarkers, parameters, data, materials, processes, procedures, evaluations, tools, and techniques for CTO interventions. This article summarizes the effort and is organized into 3 sections: key elements and procedural definitions, end point definitions, and clinical trial design principles. The Chronic Total Occlusion Academic Research Consortium is a first step toward improved comparability and interpretability of study results, supplying an increasingly growing body of CTO percutaneous coronary intervention evidence.

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

OBJECTIVES: We aimed to evaluate the efficacy and safety of antegrade fenestration and reentry (AFR) for chronic total occlusion (CTO) recanalization in a multicenter registry. BACKGROUND: Adoption of antegrade dissection/reentry (ADR) for CTO recanalization has been limited, and novel ADR techniques are needed. METHODS: AFR involves the balloon-induced creation of multiple fenestrations between the false and true lumen. A targeted true lumen reentry is subsequently achieved with a low tip-load polymer-jacketed guidewire. Following the initial description and dissemination of AFR, patients undergoing AFR-based CTO recanalization at nine centers were included in the present registry. Study endpoints were AFR success, procedural success, and target-lesion failure (TLF) on follow-up. RESULTS: We included 41 patients. Mean J-CTO score was 2.5 ± 1.4. In 80.5% of cases, AFR was performed after failed antegrade wire escalation. Another ADR technique was used before AFR in one-third of cases. AFR achieved distal true lumen reentry in n = 27/41 (65.9%) cases. In n = 14/41 (34.1%) cases with AFR failure, use of alternative techniques led to successful CTO recanalization in eight additional patients. The overall technical and procedural success rates were 85.4% and 82.9%, respectively. No AFR-related complications were observed. One-year TLF rate was 8.3% overall, with no differences between successful and failed AFR. CONCLUSIONS: We report on AFR feasibility in a multicenter registry of patients undergoing CTO recanalization. We observed a moderate success rate, coupled with the absence of complications. Moreover, even a failed AFR attempt did not preclude the use of alternative techniques to achieve recanalization. Further studies should confirm and extend our findings.

Clinical outcomes of double stent strategy for unprotected left main distal bifurcation lesions using current generation drug eluting stent comparing to early generation drug eluting stent; The Milan and New Tokyo (MITO) registry.

BACKGROUND: There are only little data available on the comparison of clinical outcomes between a early generation drug eluting stent (eDES) and a current generation drug eluting stent (cDES) for percutaneous coronary intervention (PCI) with double stent strategy (DSS) for unprotected distal left main disease (ULMD). METHODS: Between April 2005 and December 2015, we recruited 452 consecutive ULMD patients treated with DSS (eDES, 236 patients; cDES, 216 patients). In this study, eDES included Cipher, Taxus, and Endeavor and cDES included Ultimaster, Resolute family, Xience family, Promus family, Synergy, and Nobori. The primary endpoint was target lesion failure (TLF) defined as a composite of cardiac death, target lesion revascularization (TLR) and myocardial infarction (MI) during the median follow-up period of 1,809(IQR: 1,190-2,510) days. RESULTS: In entire population, the rate of overall TLR was significantly lower in cDES group than that in eDES group (adjusted HR 0.62, 95% CI 0.40-0.96, p = .032). The rate of TLR for the ostium of LCX was significantly lower in cDES group than that in eDES group (adjusted HR 0.63, 95% CI 0.39-0.99, p = .047). Cardiac mortality, the rate of TLR for LM-LAD, MI and definite/probable ST did not significantly differ between both groups. The results were preserved in the propensity adjusted population. CONCLUSIONS: cDES significantly improved the clinical outcomes in population treated with DSS mainly driven by the reduction of TLR for the ostium of LCX.

Cardiac and sudden death after chronic total occlusion percutaneous coronary intervention: Prognostic role of the target vessel.

BACKGROUND: The role of the target vessel in percutaneous revascularization of chronic total occlusion (CTO) is unclear. OBJECTIVE: We sought to assess the long-term results of percutaneous coronary intervention (PCI) for CTO lesions in each coronary artery and to investigate the impact of successful revascularization and previous myocardial infarction (MI) in the territory of the target vessel. METHODS AND RESULTS: Cohort observational study on 1,124 patients who have undergone CTO PCI attempt: 371 on left anterior descending artery (LAD), 485 right coronary artery, and 268 left circumflex. Patients were further stratified by successfully revascularized and not-revascularized CTO (CTO-NR). Vessels affected by a previous MI were defined as infarct-related artery (IRA). The primary endpoint was cardiac death; the secondary endpoint was the combined rate of sudden cardiac-death and sustained ventricular-arrhythmias (SCD/SVAs). Propensity score-matching was performed to evaluate LAD versus NON-LAD CTO. Up to 12-year follow-up, the clinical benefit associated with successful PCI was consistent across the three groups. CTO-NR had the greatest association with cardiac death and SCD/SVAs in each coronary artery and in IRA-CTO patients. CONCLUSIONS: Unsuccessful percutaneous CTO revascularization was associated with lower cardiac survival and freedom from SCD/SVAs, irrespective of the vessel treated. This result was mainly driven by patients with an IRA CTO.