Temporal Trends in Chronic Total Occlusion Interventions in Europe

Intravascular Imaging Improves Clinical Outcomes of Percutaneous Coronary Intervention for Chronic Total Occlusions: A Meta-Analysis of Randomized Controlled Trials

Clinical data comparing intravascular imaging (IVI)-guided percutaneous coronary intervention (PCI) with angiography-guided PCI for chronic total occlusions (CTOs) are limited. This study aimed to compare clinical outcomes of IVI-guided versus angiography-guided PCI in patients with CTOs. A systematic review and meta-analysis were conducted to identify randomized controlled trials (RCTs) comparing IVI-guided with angiography-guided PCI in CTO populations. The primary endpoint was the incidence of major adverse cardiac events (MACE), a composite of death/cardiac death, myocardial infarction (MI), and target-vessel revascularization (TVR). Secondary outcomes included the individual components of MACE. A prespecified subgroup analysis was performed for intravascular ultrasound (IVUS) and optical coherence tomography (OCT). Five RCTs, including 1,296 patients, were analyzed, with 713 (55%) undergoing IVI-guided PCI. Over 1 to 3 years, MACE was significantly lower in the IVI-guided PCI group (7.2% vs 13%; relative risk [RR] 0.55; 95% confidence interval [CI] 0.35 to 0.88; p = 0.012; I² = 31%). In the secondary analysis, TVR incidence was lower in the IVI group (3.1% vs 6.7%; RR 0.52; 95% CI 0.29 to 0.97; p = 0.038). No statistical differences were observed for MI or death/cardiac death. In the IVUS subgroup, MACE was also lower in the IVI-guided PCI group (8.4% vs 14.3%; RR 0.59; 95% CI 0.37 to 0.91; p = 0.019). A trial sequential analysis suggested a low likelihood of type I error. In conclusion, IVI-guided PCI is associated with improved clinical outcomes compared with angiography-guided PCI for the treatment of CTOs.

Comparative Analysis of SYNTAX and BCIS Jeopardy Score of Diabetics Versus Non-Diabetic Patients with Complex Coronary Artery Disease

Background: Diabetic patients tend to have complex coronary artery disease (CAD). Understanding their procedural risk may help to guide treatment strategies. SYNTAX and the British Cardiovascular Intervention Society Jeopardy Score (BCIS-JS) have been used to define complex CAD, but their use has not been compared in diabetic patients. Methods: This is a retrospective analysis of prospectively collected data of consecutive patients who underwent complex percutaneous coronary intervention (PCI) and were deemed unsuitable for surgical revascularization. Both SYNTAX and BCIS-JS were calculated by experienced operators who were blinded to patient's outcome. The primary endpoint was all-cause mortality at 12 months. Results: Of 452 patients included in the study, diabetes was present in 35% patients. There was a modest relationship between BCIS-JS and SYNTAX score (Spearman r = 0.44, p < 0.001) and this relationship was even weaker in patients with diabetes (Spearman r = 0.32, p < 0.001). The primary endpoint was comparable in the non-diabetic group, irrespective of the score system (SYNTAX or BCIS-JS) used to define complex CAD. In contrast, there was a differential prognostic outcome in the diabetic group, whereby the primary endpoint was more frequently reported in diabetic patients with high versus low SYNTAX scores [HR 4.96, 95% CI (1.44-17.03), p = 0.011] but not when BCIS-JS was used. Conclusions: There was a modest relationship between BCIS-JS and SYNTAX score. Unlike BCIS-JS, the SYNTAX score identified those who are at increased risk of death among diabetic patients. Both scoring systems did not effectively differentiate mortality risk in non-diabetic patients. Future research is needed to confirm this study's findings.

ECG-derived DETERMINE score can provide information about procedure success in chronic total occlusion patients

BACKGROUND

Successful chronic total occlusion (CTO) interventions may provide symptomatic relief, improve left ventricular ejection fraction (LVEF), and improve clinical outcomes. In contrast, unsuccessful interventions may increase major adverse cardiovascular event rates. Several studies have investigated various scoring systems used to predict procedural success. The DETERMINE score is an electrocardiography (ECG) score that includes Q waves, fragmented QRS, and T wave inversions. This study aimed to investigate the relationship between the procedural success of CTO and the ECG-derived DETERMINE score system.

METHODS

Our study included 301 patients. The patients were divided into successful revascularization (69 %) and unsuccessful revascularization (31 %).

RESULTS

The unsuccessful revascularization group had a higher history of coronary artery disease, lower glomerular filtration rate (GFR) levels, lower left LVEF, higher j-CTO score, less good coronary collateral, higher retrograde approach, longer QRS interval, longer QT and QTc interval, and higher DETERMINE score than the successful revascularization group. The multivariate logistic regression test results indicated LVEF, j-CTO score, absence of good coronary collateral, and DETERMINE score as independent predictive parameters for unsuccessful revascularization.

CONCLUSION

Predicting procedural success in CTO patients is crucial, especially when selecting patients. The DETERMINE score, obtained from the ECG, may aid in decision-making.

Ventricular arrhythmias in patients with chronic total occlusion of coronary arteries: a review focused on interventional treatments

A chronic total occlusion (CTO) of a coronary artery is present in almost one-fifth of patients undergoing a scheduled coronary angiography. A CTO may be classified as infarct related when there is evidence of myocardial dysfunction in the territory of the obstructed vessel or as non-infarct related when the myocardial substrate has preserved its systolic function. The presence of a CTO has been associated with an increased risk of malignant ventricular arrhythmias (VAs), appropriate ICD shocks, and cardiac mortality, with infarct-related CTOs exhibiting a worse prognosis. During the last decade, technological advancements have improved the success rates of transcatheter revascularization, a treatment that has been proven valuable for persistently symptomatic patients. However, the role of revascularization in reducing the arrhythmic burden is unclear. On the contrary, catheter ablation of VAs has been suggested to be effective, despite the presence of a CTO. As for device therapies, an increased prevalence of appropriate ICD shocks should be expected in this population, bringing into consideration the implementation of the presence of CTO as a risk modifier in sudden cardiac death prevention algorithms. The aim of this review is to present the existing literature on the role of all kinds of interventions in the management of patients with CTOs and VAs.

Machine Learning-Based Algorithm to Predict Procedural Success in a Large European Cohort of Hybrid Chronic Total Occlusion Percutaneous Coronary Interventions

CTOs are frequently encountered in patients undergoing invasive coronary angiography. Even though technical progress in CTO-PCI and enhanced skills of dedicated operators have led to substantial procedural improvement, the success of the intervention is still lower than in non-CTO PCI. Moreover, the scores developed to appraise lesion complexity and predict procedural outcomes have shown suboptimal discriminatory performance when applied to unselected cohorts. Accordingly, we sought to develop a machine learning (ML)-based model integrating clinical and angiographic characteristics to predict procedural success of chronic total occlusion (CTO)-percutaneous coronary intervention(PCI). Different ML-models were trained on a European multicenter cohort of 8904 patients undergoing attempted CTO-PCI according to the hybrid algorithm (randomly divided into a training set [75%] and a test set [25%]). Sixteen clinical and 16 angiographic variables routinely assessed were used to inform the models; procedural volume of each center was also considered together with 3 angiographic complexity scores (namely, J-CTO, PROGRESS-CTO and RECHARGE scores). The area under the curve (AUC) of the receiver operating characteristic curve was employed, as metric score. The performance of the model was also compared with that of 3 existing complexity scores. The best selected ML-model (Light Gradient Boosting Machine [LightGBM]) for procedural success prediction showed an AUC of 0.82 and 0.73 in the training and test set, respectively. The accuracy of the ML-based model outperformed those of the conventional scores (J-CTO AUC 0.66, PROGRESS-CTO AUC 0.62, RECHARGE AUC 0.64, p-value <0.01 for all the pairwise comparisons). In conclusion, the implementation of a ML-based model to predict procedural success in CTO-PCIs showed good prediction accuracy, thus potentially providing new elements for a tailored management. Prospective validation studies should be conducted in real-world settings, integrating ML-based model into operator decision-making processes in order to validate this new approach.

Clinical and subclinical acute brain injury caused by invasive cardiovascular procedures

Over the past 50 years, the number and invasiveness of percutaneous cardiovascular procedures globally have increased substantially. However, cardiovascular interventions are inherently associated with a risk of acute brain injury, both periprocedurally and postprocedurally, which impairs medical outcomes and increases health-care costs. Current international clinical guidelines generally do not cover the area of acute brain injury related to cardiovascular invasive procedures. In this international Consensus Statement, we compile the available knowledge (including data on prevalence, pathophysiology, risk factors, clinical presentation and management) to formulate consensus recommendations on the prevention, diagnosis and treatment of acute brain injury caused by cardiovascular interventions. We also identify knowledge gaps and possible future directions in clinical research into acute brain injury related to cardiovascular interventions.

Recent advances and clinical implications of intravascular imaging

Coronary artery disease (CAD) remains a major contributor to the global mortality rate. Accurate and detailed evaluation of atherosclerotic plaque characteristics is essential for effective risk assessment and treatment planning. Although conventional coronary angiography excels at quantifying luminal stenosis, information on plaque composition and structure remains limited. Recent advances in intravascular imaging (IVI) have bridged this gap by enabling high-resolution visualization of the vessel wall and plaque morphology, thereby enhancing treatment strategies and facilitating comprehensive risk stratification. Among the principal IVI modalities, intravascular ultrasound (IVUS), optical coherence tomography (OCT), and near-infrared spectroscopy (NIRS) provide distinct benefits. IVUS accurately measures vessel diameter and plaque burden, offering critical guidance for managing complex lesions and left main artery disease. The extremely high spatial resolution of OCT allows precise identification of high-risk plaque features, such as thin fibrous caps. NIRS complements these techniques by quantitatively assessing lipid components within plaques, making it particularly useful in predicting future cardiovascular events. In this review, we summarize the latest evidence on applying IVI modalities to the evaluation and treatment of CAD. We focus on the assessment of plaque morphology, identification of high-risk lesions, and the role of IVI-guided percutaneous coronary intervention (PCI). The continued development of hybrid imaging systems and artificial intelligence-based image analysis may produce more precise and safer PCI approaches. Consequently, IVI is poised to become indispensable in managing CAD, paving the way for more personalized treatment strategies tailored to the specific lesion characteristics of each patient.

Indications, Management, and Short- and Medium-Term Outcomes of Patients with Chronic Coronary Occlusion Treated with Percutaneous Revascularization-A Single-Center Study

The diagnosis of chronic total occlusion (CTO), characterized by the complete obstruction of a coronary artery for at least three months, remains challenging and can be entirely asymptomatic. Since the indications for performing a recanalization procedure for CTO do not originate from randomized controlled trials, this study aimed to assess the indications, management, and procedural outcomes of patients undergoing percutaneous revascularization (PCI) for a CTO, ensuring that the population was as uniform as possible regarding technologies and methodological approaches. Forty-one consecutive patients who underwent PCI for CTO recanalization were enrolled from January 2021 to 2024. Additional outcomes included mortality, major adverse cardiovascular events, and the presence of residual cardiac symptoms, with a median follow-up of 449 days and an interquartile range of 230-643 days. Our real-life study confirmed that PCI for CTO has a high success rate and a low incidence of major complications.

New Frontiers in Antegrade Wiring From the Asia Pacific Chronic Total Occlusion Club

Antegrade wiring (AW) is the prevailing chronic total occlusion (CTO) crossing technique. For proximal cap ambiguity, the Global CTO consensus group uses the "anatomy dictates strategy" method: 1) intravascular ultrasound; 2) move the cap; or 3) retrograde. For CTO body crossing, anatomy dictates 4 strategies: 1) CTOs with tapered stump-loose tissue tracking; 2) CTOs with clear intimal path-intentional intimal tracking with 3-dimensional (3D) wiring; 3) CTOs without a clear intimal path-intentional intimal tracking with intermediate penetration wire; and 4) the "long plus CTOs"-intentional subintimal wiring. The new angiographic 3D antegrade puncture technique from the APCTO (Asia Pacific Chronic Total Occlusion) Club is presented for distal cap puncture. angiographic 3D antegrade puncture technique can be used as a 3D wiring technique as well as an antegrade dissection and re-entry technique. Based on these new frontiers, we have updated our APCTO algorithm in this paper. This update can form a basis for research and training.

Computed Tomography Angiography in the Catheterization Laboratory: A Guide Towards Optimizing Coronary Interventions

Cardiac computed tomography (CT) has become an essential tool in the pre-procedural planning and optimization of coronary interventions. Its non-invasive nature allows for the detailed visualization of coronary anatomy, including plaque burden, vessel morphology, and the presence of stenosis, aiding in precise decision making for revascularization strategies. Clinicians can assess not only the extent of coronary artery disease but also the functional significance of lesions using techniques like fractional flow reserve (FFR-CT). By providing comprehensive insights into coronary structure and hemodynamics, cardiac CT helps guide personalized treatment plans, ensuring the more accurate selection of patients for percutaneous coronary interventions or coronary artery bypass grafting and potentially improving patient outcomes.

Retrograde approach to chronic total occlusion percutaneous coronary interventions- Technique and outcomes

The retrograde approach to chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has significantly contributed to the success rates of CTO PCI. It is usually performed in complex CTO lesions, in which the antegrade approach is not feasible or fails. In this article we discuss the steps to perform retrograde CTO PCI and its complications and success rates. Considering the moderate to high success rates of the retrograde approach in the hands of experienced operators and higher complication rates than antegrade only procedures, optimizing the safety of retrograde CTO PCI is of paramount importance.

Sub-Intimal Tracking and Re-Entry and Investment Procedures: Current Applications and Future Directions

In seeking to improve upon chronic total occlusion (CTO) percutaneous coronary intervention success rates and minimize risk, CTO modification procedures (investment procedures) have been developed and utilized with increasing frequency. Two key techniques have emerged: subintimal tracking and re-entry (STAR) and subintimal plaque modification (SPM). Both require a staged approach with an index procedure for plaque modification and a second procedure weeks later for stenting. Both approaches require entry and wiring with a polymer-jacketed wire in the extra-plaque space, yet unlike SPM, which exclusively requires angioplasty of the extra-plaque space throughout the CTO segment, STAR also involves re-entry into the true luminal distal to the CTO before angioplasty. STAR and SPM, in many ways, represent a paradigm shift in our approach to CTO percutaneous coronary intervention from a 1-step to a 2-step approach in complex cases. In this review, we discuss the technical aspects of the procedures, and controversies and ongoing trials pointing to the future of these techniques. We also highlight non-device-based and intravascular ultrasound-based approaches to anterograde dissection and re-entry, which add to the CTO operator's toolkit for challenging cases.

Wire Escalation And De-escalation Techniques in Antegrade and Retrograde Approaches to Chronic Total Occlusion Percutaneous Coronary Interventions

Coronary chronic total occlusions (CTO) are frequently identified during coronary angiography and remain the most challenging subset of coronary artery lesions to treat; however, advancements in techniques and materials have greatly improved success rates. Various crossing algorithms have been developed to standardise the approach to CTO interventions based on angiographic criteria. Antegrade wiring is typically the initial strategy of choice, particularly in cases of short and straight CTOs with tapered proximal cap. Similarly, retrograde crossing can be achieved through retrograde wiring, although this approach has a very low success rate. This review aims to outline how to perform a CTO analysis, clarify the fundamental features of guidewires and provide insights into both antegrade and retrograde wire-based approaches.

The impacts of percutaneous coronary intervention to treat chronic total occlusion of right coronary artery on the 5-year prognosis: A single-centered retrospective study

BACKGROUND

Chronic total occlusions (CTO) occur in about 20% of patients referred for coronary angiography, and right coronary artery (RCA) CTO has been reported in 38-50% of the entire CTO population. Limited data on angiographic and procedural characteristics of RCA-CTO and the risk of adverse cardiac events asks for a detailed study.

METHODS

From 2010 to 2013, patients with attempted revascularization of at least one CTO lesion were included and followed up to 5 years after PCI. Eligible patients are assigned to RCA-CTO and non-RCA-CTO groups based on their target vessels. The primary endpoint was major adverse cardiovascular events (MACEs; a composite of all-cause death, myocardial infarction (MI) or rehospitalization for heart failure), and secondary endpoints were cardiac death, target lesion revascularization (TLR) and target vessel revascularization (TVR).

RESULTS

The present study included 2659 eligible patients, among which 1285 patients were assigned to the RCA-CTO group, whereas 1374 patients were assigned to the non-RCA-CTO group. Lesions in RCA had longer lesion length, higher J-CTO score, higher rates of severe vessel tortuosity, a higher percentage of Rentrop grade 2-3, and more likely to be re-try lesion than those in LAD or LCX (all P < 0.01). CTO lesions in RCA reached less successful recanalization and post-procedural TIMI 3 flow (all <0.01). Multivariate Cox analysis revealed that RCA-CTO was not associated with primary outcome MACEs. Besides MACEs, RCA-CTO was also not associated with cardiac death, but was significantly associated with TLR and TVR (adjusted HR: 1.37 [95% CI:1.07-1.76], P = 0.01; adjusted HR: 1.43 [95% CI:1.13-1.82], P = 0.003).

CONCLUSION

RCA-CTO lesions, which had more complex angiographic features, independently contributed to TLR and TVR but not to MACEs or cardiac death in the 5 years of follow-up.

Intravascular lithotripsy in heavily calcified chronic total occlusion: procedural and one-year clinical outcomes

BACKGROUND

Calcification within chronic total occlusions (CTO) is strongly associated with worse outcomes. Despite the excellent success and safety of intravascular lithotripsy (IVL) in heavily calcified lesions, evidence in CTO remains scarce.

AIM

This study aimed to evaluate the procedural and long-term clinical outcomes of IVL in heavily calcified CTO.

METHODS

Patients who underwent IVL between 2019 and 2024 from an ongoing prospective multicenter registry were eligible for inclusion. Patients were therefore classified in CTO and non-CTO groups. The efficacy and safety endpoints of CTO percutaneous coronary interventions were defined according to the CTO-ARC consensus. In-hospital major adverse cardiovascular events (MACE) included cardiac death, nonfatal myocardial infarction and target lesion revascularization (TVR).

RESULTS

A total of 404 patients underwent IVL, of which the treated lesion was a CTO in 33 (8.2%). The mean J-CTO score was 2.3 ± 1.1. Device success showed no significant difference between CTO and non-CTO groups (100% vs 98.4%; p = 0.35). Comparable technical success with residual stenosis <30% was observed in both groups (90.1% in CTO vs 89.2% in non-CTO, p = 0.83). The incidence of MACE was similar across groups during hospital stays (CTO 6.0% vs. non-CTO 1.9%, p = 0.12), at 30-day (CTO 9.1% vs. non-CTO 3.0%, p = 0.07), and at 12-month follow-up (CTO 9.1% vs. non-CTO 7.3%, p = 0.70).

CONCLUSION

IVL provides high procedural success and consistent clinical outcomes in both CTO and non-CTO cases, reinforcing its role in managing heavily calcified coronary lesions.

The impact of successful chronic total occlusion percutaneous coronary intervention on clinical outcomes: a tertiary single-center analysis

Background

The benefit of chronic total occlusion (CTO)-percutaneous coronary intervention (PCI) is controversial because of a lack of high-quality evidence. We aim to evaluate the impact of CTO-PCI on symptoms, quality of life and mortality.

Methods

We conducted a retrospective single center study of patients with CTO-PCI in a tertiary center in Austria. The study outcomes were Canadian Cardiovascular Society (CCS) angina score, quality of life measured by Seattle Angina Questionnaire (SAQ), and death at median follow up for patients with successful vs. failed CTO-PCI.

Results

A total of 300 patients underwent CTO-PCI for coronary artery disease, of which 252 (84%) were technically successful with median follow up of 3.4 years. There were no significant differences in in-hospital or all-cause mortality, major adverse cardiovascular event, or stent-related complications between the groups of failed and successful CTO-PCI. Among patients with successful CTO-PCI there was a significant improvement in CCS score, which was not found for the group with failed CTO-PCI. Successful reopening was associated with significant benefits of the SAQ domains of angina with stressful activity [3.7 ± 0.9 vs. 3.1 ± 0.5, p = 0.004, use of nitrates (4.7 ± 0.5 vs. 3.0 ± 1.0) p = 0.005] and satisfaction from angina relief (4.4 ± 1.1 vs. 3.6 ± 1.4 p < 0.001).

Conclusion

While there was no significant difference in mortality, successful CTO-PCI was associated with greater reduction in angina and the use of nitrates compared to unsuccessful CTO-PCI.

Who Should Undergo Chronic Total Occlusions Percutaneous Coronary Intervention and When?: An Evidence-Based Approach to the Patient Referred for Percutaneous Coronary Intervention of Chronic Total Occlusion

Chronic total occlusions (CTO) of the coronary arteries are common among patients presenting to the cardiac catheterization laboratory, and data suggests a worse overall prognosis in patients with CTOs. Percutaneous coronary intervention (PCI) of CTOs has been shown to improve anginal symptoms in observational studies and in a limited number of randomized trials. However, CTO PCI has not been shown to lead to a reduction in other important end points such as myocardial infarction or death. Furthermore, despite recent advances in the field, CTO PCI still carries higher risks and a lower likelihood of success compared with non-CTO PCI. Thus, determining which patients may be appropriate for CTO PCI is challenging and must involve a comprehensive risk-benefit analysis and discussion with the patient. Therefore, we review the currently available data regarding CTO PCI, including the clinical outcomes, the role of preprocedural ischemia testing, and various procedural success and risk stratification scores. Finally, we present our approach to the patient referred for CTO PCI.

Current evidence for prognostic benefit of intravascular imaging-guided percutaneous coronary intervention in chronic total occlusion intervention

Although percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) has been increasing in recent years, CTO PCI is still one of the most challenging procedures with relatively higher rates of procedural complications and adverse clinical events after PCI. Due to the innate limitations of invasive coronary angiography, intravascular imaging (IVI) has been used as an adjunctive tool to complement PCI, especially in complex coronary artery disease. Considering the complexity of CTO lesions, the role of IVI is particularly important in CTO intervention. IVI has been a useful adjunctive tool in every step of CTO PCI including assisted wire crossing, confirmation of wire location within CTO segment, and stent optimization. The meticulous use of IVI has been one of the greatest contributors to recent progress of CTO PCI. Nevertheless, studies evaluating the role of IVI during CTO PCI are limited. The current review provides a comprehensive overview of the mechanistic advantages of IVI in CTO PCI, summarizes previous studies and trials, and presents future perspective of IVI in CTO PCI.

Annual operator volume and procedural outcomes of chronic total occlusions treated with percutaneous coronary interventions: analysis based on 14,899 patients

BACKGROUND

Low operator and institutional volume is associated with poorer procedural and long-term clinical outcomes in patients treated with percutaneous coronary interventions (PCI). This study was aimed at evaluating the relationship between operator volume and procedural outcomes of patients treated with PCI for chronic total occlusion (CTO).

METHODS

Data were obtained from the national registry of percutaneous coronary interventions (ORPKI) collected from January 2014 to December 2020. The primary endpoint was a procedural success, defined as restoration of thrombolysis in myocardial infarction (TIMI) II/III flow without in-hospital cardiac death and myocardial infarction, whereas secondary endpoints included periprocedural complications.

RESULTS

Data of 14,899 CTO-PCIs were analyzed. The global procedural success was 66.1%. There was a direct relationship between the annual volume of CTO-PCIs per operator and the procedural success (OR: 1.006 [95% CI: 1.003-1.009]; P<0.001). The nonlinear relationships of annualized CTO-PCI volume per operator and adjusted outcome rates revealed that operators performing 40 CTO cases per year had the best procedural outcomes in terms of technical success (TIMI flow II/III after PCI), coronary artery perforation rate and any periprocedural complications rate (P<0.0001). Among the other factors associated with procedural success, the following can be noted: multi-vessel, left main coronary artery disease (as compared to single-vessel disease), the usage of rotablation as well as PCI within bifurcation.

CONCLUSIONS

High-volume CTO operators achieve greater procedural success with a lower frequency of periprocedural complications. Higher annual caseload might increase the overall quality of CTO-PCI.

Impact of Bifurcation Involvement and Location in Chronic Total Occlusion Percutaneous Coronary Intervention: Insights From the EuroCTO Registry

Bifurcation involvement close to or within the occluded segment poses increasing difficulties for chronic total occlusion (CTO)-percutaneous coronary intervention (PCI). However, this variable is not considered in the angiography-based CTO scoring systems nor has been extensively investigated in large multicenter series. Accordingly, we analyzed a CTO-PCI registry involving 92 European centers to explore the incidence, angiographic and procedural characteristics, and outcomes specific to CTO-PCIs with bifurcation involvement. A total of 3,948 procedures performed between January and November 2023 were examined (33% with bifurcation involvement). Among bifurcation lesions, 38% and 37% were located within 5 mm of the proximal and distal cap, respectively, 16% within the CTO body, and in 9% of cases proximal and distal bifurcations coexisted. When compared with lesions without bifurcation involvement, CTO bifurcation lesions had higher complexity (J-CTO 2.33 ± 1.21 vs 2.11 ± 1.27, p <0.001) and were associated with higher use of additional devices (dual-lumen microcatheter in 27.6% vs 8.4%, p <0.001, and intravascular ultrasound in 32.2% vs 21.7%, p <0.001). Radiation dose (1,544 [836 to 2,819] vs 1,298.5 [699.1 to 2,386.6] mGy, p <0.001) and contrast volume (230 [160 to 300] vs 190 [130 to 250] ml, p <0.001) were also higher. Technical success was similar (91.5% with bifurcation involvement vs 90.4% without bifurcation involvement, p = 0.271). However, the bifurcation lesions within the CTO segment (intralesion) were associated with lower technical success than the other bifurcation-location subgroups (83.7% vs 93.3% proximal, 93.4% distal, and 89.0% proximal and distal, p <0.001). On multivariable analysis, the presence of an intralesion bifurcation was independently associated with technical failure (odds ratio 2.04, 95% confidence interval 1.24 to 3.35, p = 0.005). In conclusion, bifurcations are present in approximately one-third of CTOs who underwent PCI. PCI of CTOs with bifurcation can be achieved with high success rates except for bifurcations within the occluded segment, which were associated with higher technical failure.

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.

Global Consensus Recommendations on Improving the Safety of Chronic Total Occlusion Interventions

Safety is of critical importance to chronic total occlusion (CTO) percutaneous coronary intervention (PCI). This global consensus statement provides guidance on how to optimise the safety of CTO) PCI, addressing the following 12 areas: 1. Set-up for safe CTO PCI; 2. Guide catheter--associated vessel injuries; 3. Hydraulic dissection, extraplaque haematoma expansion, and aortic dissections; 4. Haemodynamic collapse during CTO PCI; 5. Side branch occlusion; 6. Perforations; 7. Equipment entrapment; 8. Vascular access considerations; 9. Contrast-induced acute kidney injury; 10. Radiation injury; 11 When to stop; and, 12. Proctorship. This statement complements the global CTO crossing algorithm; by advising how to prevent and deal with complications, this statement aims to facilitate clinical practice, research, and education relating to CTO PCI.

Ionizing radiation exposure in complex percutaneous coronary intervention: Defining local diagnostic reference levels in the catheterization laboratory

INTRODUCTION AND OBJECTIVES

Concerns regarding the consequences of ionizing radiation (IR) have been increasing in the field of interventional cardiology (IC). There is little information on reported national and local radiation diagnostic reference levels (DRLs) in catheterization laboratories in Portugal. This study was designed to assess the IR dose exposure during complex percutaneous coronary intervention (PCI), and to set the respective DRLs and future achievable doses (ADs).

METHODS

This was a retrospective cohort study which took place between 2019 and 2020, including patients who underwent complex PCI. Complex PCI was defined as all procedures that encompass treatment of chronic total occlusions (CTO) or left main coronary artery. DRLs were defined as the 75th percentile of the distribution of the median values of air kerma area product (PKA) and cumulative air kerma (Ka,r). ADs were set at the 50th percentile of the study dose distribution. Multivariate analysis was performed using linear regression to identify predictors significantly associated with radiation dose (Ka,r).

RESULTS

A total of 242 patients were included in the analysis. Most patients underwent a CTO procedure (146, 60.3%). Patients were aged 67.9±11.2 years and mostly male (81.4%). DRLs were set in Ka,r (3012 mGy) and PKA (162 Gy cm2) for complex PCI. ADs were also set in Ka,r (1917 mGy) and PKA (101 Gy cm2). Independent predictors of Ka,r with a positive correlation were PKA (0.893, p<0.001), fluoroscopy time (0.520, p<0.001) and PCI time (0.521, p<0.001).

CONCLUSIONS

This study reports the results of IR in complex PCI. DRLs were set for IR dose exposure measured in Ka,r (3012 mGy) and PKA (162 Gy cm2). ADs, values to be achieved in future assessment, were set to Ka,r (1917 mGy) and PKA (101 Gy cm2).

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.

Coronary Chronic Total Occlusion Revascularization: When, Who and How?

Coronary chronic total occlusions (CTO) are an increasingly frequent entity in clinical practice and represent a challenging percutaneous coronary intervention (PCI) scenario. Despite data from randomized trials that have not yet demonstrated a clear benefit of CTO recanalization, the widespread of CTO-PCI has substantially increased. The improvement in operators' techniques, equipment, and training programs has led to an improvement in the success rate and safety of these procedures, which will represent an important field of future development of PCI. The present review will summarize clinical outcomes and technical and safety issues of CTO revascularization with the aim to guide clinical daily cath-lab practice.

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.

Performance of the minimalistic hybrid approach algorithm versus other conventional algorithms in the percutaneous treatment of chronic total occlusions

BACKGROUND

The "Minimalistic Hybrid Approach" (MHA) has been proposed to reduce the invasiveness of chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

AIMS

This study aims to assess whether MHA may also reduce the utilization of PCI resources (devices, radiations, and contrast) by comparing it with other conventional algorithms.

METHODS

We aimed to assess the impact of MHA on device, radiation, and contrast usage during CTO-PCI analyzing data from the Belgian Working Group on CTO (BWG-CTO) registry. Patients were divided, depending on the algorithm used, into two groups: Conventional versus Minimalistic. Primary objectives were procedure performance measures such as device usage (microcatheters and guidewires), radiological parameters, and contrast use. At 1-year follow-up, patients were evaluated for target vessel failure (TVF), defined as a composite of cardiac death, new myocardial infarction, and target vessel revascularization.

RESULTS

Overall, we analyzed 821 CTO-PCIs (Conventional n = 650, Minimalistic n = 171). The Minimalistic group demonstrated higher complexity of CTO lesions. After adjusting for propensity score, the Minimalistic group had a significantly lower number of microcatheters used (1.49 ± 0.85 vs. 1.24 ± 0.64, p = 0.026), while the number of guidewires was comparable (4.80 ± 3.29 vs. 4.35 ± 2.94, p = 0.30). Both groups had similar rates of success and procedural complications, as well as comparable procedural and fluoroscopic times and contrast volume used. At the 1-year follow-up, both groups showed comparable rates of TVF (hazard ratio: 0.57; 95% confidence interval: 0.24-1.34, p = 0.195).

CONCLUSION

The MHA may slightly reduce the number of dedicated devices used during CTO-PCI, without adversely affecting the procedural success or long-term outcome.

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.

Prevalence of Collateral Typology in Coronary Chronic Total Occlusion and Its Impact on Percutaneous Intervention Performance

The presence of collateral channels providing distal blood supply is a distinctive characteristic of chronic total occlusion (CTO) lesions. However, data about the distinct baseline and procedural characteristics of each collateral subset are scarce. Accordingly, we sought to explore the procedural aspects specific for each collateral typology (ipsilateral collaterals [ICs], contralateral collaterals [CCs] or mixed) in CTO-percutaneous coronary intervention (PCI). A retrospective analysis of our CTO-PCI registry was performed to investigate the prevalence, procedural characteristics, and outcomes specific for each CTO-PCI subset, defined according to the inter-arterial connection anatomy. A total of 209 cases were included. Of the included cases, 45 (22%) and 92 (44%) patients displayed solely IC or CC, respectively, whereas in 72 (34%) both IC and CC were present (mixed). The procedural success rate was high (91.1%) and comparable among the different groups, despite greater lesion complexity in the CC group. The most frequent target vessel was the left circumflex in the IC group (51% of cases) and the right coronary artery in the CC (63%) and mixed (57%) groups. Among the IC cases, 42% showed a poor collateral connection function (2% and 10% for the CC and mixed group, respectively), and 46% showed a suboptimal collateral recipient artery filling (21% and 20% for the CC and mixed group, respectively). Most of the IC cases were performed using a single access (96%). In conclusion, the success and complication rates were comparable among the collateral typology groups, irrespective of the differences in the baseline and procedural characteristics. Phenotyping CTO as hereby proposed might be helpful for targeted procedural considerations.

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.

Early and long-term prognosis in patients with remaining chronic total occlusions after revascularization attempt. A cohort study from the SKEJ-CTO registry

OBJECTIVES

The present study aimed to compare safety and long-term prognosis of patients with chronic total coronary occlusions (CTO) stratified for remaining CTOs after percutaneous coronary intervention (PCI).

DESIGN

The study cohort consisted of patients with coronary artery disease who underwent CTO PCI in a high volume tertiary center from 2009 to 2019 and were registered in Danish high-quality registers. Patients with successful PCI of all CTOs were compared to patients with ≥1 remaining CTO post-procedural. Primary endpoints were analysed using Cox-regression and Kaplan-Meier estimates, and included all-cause mortality, major adverse cardio- and cerebrovascular events (MACCE) and a 30-day safety endpoint.

RESULTS

Procedural success rate was 87.7%, and 76.5% of patients had all CTO(s) opened post-PCI. Safety endpoint occurred in 4.6% of patients, and more frequently in patients with remaining CTO(s) (RD 4.9, 95%CI 0.1, 9.8). All-cause mortality was higher in patients with remaining CTO(s) (Unadjusted HR 1.65, 95% CI 1.03, 2.47, p = .015. Adjusted HR 1.32, 95%CI 0.88-1.99, p = .18) after eight years of follow-up. Risk of MACCE was significantly higher in patients with remaining CTO(s) (Unadjusted HR 1.79, 95% CI 1.34-2.41, p < .001. Adjusted HR 1.51, 95% CI 1.11-2.05, p = .009).

CONCLUSIONS

In our centre, CTO PCI was associated with high success rate and low risk of 30-days complications. Presence of remaining CTO(s) after final revascularization attempt was associated with higher but statistically insignificant long-term mortality but was an independent predictor of MACCE.

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.

Gender-Based Differences in Outcomes After Percutaneous Coronary Intervention of Chronic Total Occlusions (Insights from a Large Single-Center Registry)

Patients who undergo percutaneous coronary intervention (PCI) of chronic total occlusions (CTO) are at a high risk for both periprocedural and post-procedural adverse events. Whether gender-differences in outcomes exist after PCI of CTO remain unclear. Therefore, we sought to investigate gender-based differences in outcomes after CTO-PCI. All patients who underwent elective CTO intervention from January 2012 to December 2017 at The Mount Sinai Hospital (New York, New York) were included. The primary end point of interest was major adverse cardiac events defined as the composite of death, myocardial infarction, and target vessel revascularization at 1 year of follow-up. A total 1,897 patients were included, of which 368 were women (19.4%). Mean follow-up time was 174 days. Women were older (66.8 ± 11.3 years vs 62.6 ± 10.9 years) and had a higher prevalence of co-morbidities including diabetes and chronic kidney disease. There were no significant differences in the rate of successful CTO-PCI between groups (73.5% vs 73.2%, p = 0.91). Women had higher rates of procedure-related complications including increased risk of post-procedural bleeding (4.1% vs 1.8%, p = 0.009) and acute vessel closure (1.36% vs 0.2%, p = 0.009). In multivariable-adjusted analysis, female gender was associated with higher risk of major adverse cardiac event and target vessel revascularization at 1 year. In conclusion, in this large single-center study, women who underwent percutaneous CTO revascularization experienced higher rates of periprocedural complications and worse clinical outcomes at 1 year compared with men. Further research is needed to address disparities in gender-specific outcomes of CTO-PCI.

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.

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.

Contemporary In-Hospital Outcomes of Chronic Total Occlusion Percutaneous Coronary Interventions: Insights from the MENATA (Middle East, North Africa, Turkey, and Asia) Chapter of the PROGRESS-CTO Registry

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has been rapidly evolving in different parts of the world. We examined the clinical and angiographic characteristics and procedural outcomes of 1,079 consecutive CTO PCIs performed in 1,063 patients at 10 centers in the Middle East, North Africa, Turkey, and Asia regions between 2018 and 2022. The mean age was 61 ± 10 years and 82% of the patients were men. The prevalence of diabetes (49%) and previous PCI (50%) was high. The most common target vessel was the right coronary artery (51%), followed by the left anterior descending artery (33%) and the circumflex artery (15%). The mean Japanese CTO score was 2.1 ± 1.2 and mean PROGRESS-CTO (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention) score was 1.2 ± 1.0. The technical and procedural success rates were high (91% and 90%, respectively) with a low incidence (1.6%) of in-hospital major adverse cardiac events. The incidence of perforation was 4.6% (n = 50): guidewire exit was the most common mechanism of perforation (48%) and 14 patients required pericardiocentesis (28%). Antegrade wire escalation was the most common crossing strategy used (91%), followed by retrograde approach (24%) and antegrade dissection and re-entry (12%). Median contrast volume, air kerma radiation dose, and fluoroscopy time were 300 (200 to 400) ml, 3.7 (2.0 to 6.3) Gy, and 40 (25 to 65) minutes, respectively. In conclusion, high success and acceptable complication rates are currently achieved at experienced centers in the Middle East, North Africa, Turkey, and Asia regions using a combination of crossing strategies.

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

Background

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

Case summary

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

Discussion

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

Trends and Inhospital Outcomes of Intravascular Imaging on Single-Vessel Coronary Chronic Total Occlusion Treated With Percutaneous Coronary Intervention

Intravascular imaging (IVI), including intravascular ultrasound (IVUS) and optical coherence tomography (OCT), improves outcomes of percutaneous coronary intervention (PCI) for chronic total occlusions (CTOs). We sought to quantify temporal trends in the uptake of IVI for CTO-PCI in the United States. We identified adults who underwent single-vessel PCI for CTO between 2008 and 2020. We quantified yearly trends in the number of IVUS-guided and OCT-guided single-vessel CTO-PCIs by Cochran-Armitage and linear regression tests. We also examined the rates of inhospital mortality and other prespecified inhospital outcomes in patients who underwent CTO-PCIs with and without IVI, using logistic regression. Our study included a total of 151,998 PCIs on single-vessel CTOs, with the absolute number of CTO-PCIs decreasing from 12,345 in 2008 to 8,525 in 2020 (p trend <0.001). IVUS use has increased dramatically from 6% in 2008 to 18% in 2020 for single-vessel CTO-PCIs (p trend <0.001). Rates of OCT use have increased as well, from 0% in 2008 to 7% in 2020 (p trend <0.001). There was no difference in inhospital mortality between patients who underwent CTO-PCI with and without IVI (p logistic = 0.60). In the largest national analysis of single-vessel CTO-PCI trends to date, we found that the use of IVUS has increased substantially accompanied by a similar but lesser increase in the use of OCT. There were no differences in rates of inhospital mortality between patients who underwent single-vessel CTO-PCIs with and without IVI.

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

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

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.

Transcatheter recanalization of chronic total occlusion in congenital heart disease: case reports and lessons from percutaneous coronary interventions

Background

Chronic complete vascular occlusion causes significant morbidity and mortality in patients with congenital heart disease (CHD). The diversity of lesions, lack of dedicated equipment, and small number of procedures performed by individual operator continue to pose a challenge to congenital interventional cardiologists.

Case summary

We report two cases of percutaneous recanalization in CHD using percutaneous coronary intervention (PCI) equipment for chronic total occlusion (CTO).

Discussion

Careful pre-procedural planning, access site choice, use of catheter guiding systems for support, and selection of penetrating guidewires and techniques used in CTO-PCIs are key steps to a successful outcome.

Single versus Dual-Operator Approaches for Percutaneous Coronary Interventions within Chronic Total Occlusion-An Analysis of 27,788 Patients

(1) Background: Since the treatment of chronic total occlusion (CTO) with percutaneous coronary intervention (PCI) is associated with high procedural complexity, it has been suggested to use a multi-operator approach. This study was aimed at evaluating the procedural outcomes of single (SO) versus dual-operator (DO) CTO-PCI approaches. (2) Methods: This retrospective analysis included data from the Polish Registry of Invasive Cardiology Procedures (ORPKI), collected between January 2014 and December 2020. To compare the DO and SO approaches, propensity score matching was introduced with equalized baseline features. (3) Results: The DO approach was applied in 3604 (13%) out of 27,788 CTO-PCI cases. Patients undergoing DO CTO-PCI experienced puncture-site bleeding less often than the SO group (0.1% vs. 0.3%, p = 0.03). No differences were found in the technical success rate (successful revascularization with thrombolysis in myocardial infarction flow grade 2/3) of the SO (72.4%) versus the DO approach (71.2%). Moreover, the presence of either multi-vessel (MVD) or left main coronary artery disease (LMCA) (odds ratio (OR), 1.67 (95% confidence interval (CI), 1.20-2.32); p = 0.002), as well as lower annual and total operator volumes of PCI and CTO-PCI, could be noted as factors linked with the DO approach. (4) Conclusions: Due to the retrospective character, the findings of this study have to be considered only as hypothesis-generating. DO CTO-PCI was infrequent and was performed on patients who were more likely to have LMCA lesions or MVD. Operators collaboratively performing CTO-PCIs were more likely to have less experience. Puncture-site bleeding occurred less often in the dual-operator group; however, second-operator involvement had no impact on the technical success of the intervention.

National Trends of Percutaneous Mechanical Support Utilization During Percutaneous Coronary Interventions in Chronic Total Occlusion

Coronary chronic total occlusion (CTO) is common in patients with multivessel coronary artery disease. Percutaneous coronary artery (PCI) interventions have shown favorable outcomes in patients with CTO. Nevertheless, the data regarding the utilization of mechanical circulatory support in CTO PCIs is not well established. We sought to investigate the trends in utilization and periprocedural complications in this population. Using the National Inpatient Sample database from 2011 to 2019, we identified patients diagnosed with CTO who underwent PCI. We investigated the presence of a linear trend in the utilization of mechanical circulatory support (MCS) during those procedures and the associated periprocedural complications using the Cochran-Armitage method. A total of 208,123 patients who were diagnosed with CTO and underwent PCI from 2011 to 2019, of which in 6,319 patients MCS was used during the procedure. Patients in the MCS group were older (67.4 vs 66.4 years), less likely to be women (24.0% vs 26.4%), and equally likely to be African-American (9.4% vs 8.8%) with a higher burden of co-morbidities in terms of coronary artery disease, congestive heart failure, and atrial fibrillation (p <0.001 for all). Using the Cochrane-Armitage method, we found a statistically significant linear uptrend in the utilization of MCS from 269 (1.4%) to 990 cases (7.0%) from 2011 to 2019. Using multivariable logistic regression, female gender, renal failure, alcohol abuse, coagulopathy, and fluid and electrolyte disorders were identified as independent predictors of mortality in CTO PCI procedures assisted with MCS (p ≤0.007). In conclusion, the utilization of MCS in CTO PCI procedures has been increasing over the years. Female gender and renal failure are independently associated with a higher mortality risk.

Percutaneous Coronary Intervention for Chronic Total Occlusion-Contemporary Approach and Future Directions

In the aging society, the issue of coronary chronic total occlusion (CTO) has become a challenge for invasive cardiologists. Despite the lack of clear indications in European and American guidelines, the rates of percutaneous coronary interventions (PCI) for CTO increased over the last years. Well-conducted randomized clinical trials (RCT) and large observational studies brought significant and substantial progress in many CTO blind spots. However, the results regarding the rationale behind revascularization and the long-term benefit of CTO are inconclusive. Knowing the uncertainties regarding PCI CTO, our work sought to sum up and provide a comprehensive review of the latest evidence on percutaneous recanalization of coronary artery chronic total occlusion.

Overview of Percutaneous Coronary Interventions for Chronic Total Occlusions Treated at Brazilian Centers Participating in the LATAM CTO Registry

BACKGROUND

Major advances have been seen in techniques and devices for performing percutaneous coronary interventions (PCIs) for chronic total occlusions (CTOs), but there are limited real-world practice data from developing countries.

OBJECTIVES

To report clinical and angiographic characteristics, procedural aspects, and clinical outcomes of CTO PCI performed at dedicated centers in Brazil.

METHODS

Included patients underwent CTO PCI at centers participating in the LATAM CTO Registry, a Latin American multicenter registry dedicated to prospective collection of these data. Inclusion criteria were procedures performed in Brazil, age 18 years or over, and presence of CTO with PCI attempt. CTO was defined as a 100% lesion in an epicardial coronary artery, known or estimated to have lasted at least 3 months.

RESULTS

Data on 1196 CTO PCIs were included. Procedures were performed primarily for angina control (85%) and/or treatment of moderate/severe ischemia (24%). Technical success rate was 84%, being achieved with antegrade wire approaches in 81% of procedures, antegrade dissection and re-entry in 9%, and retrograde approaches in 10%. In-hospital adverse cardiovascular events occurred in 2.3% of cases, with a mortality rate of 0.75%.

CONCLUSIONS

CTOs can be treated effectively in Brazil by using PCI, with low complication rates. The scientific and technological development observed in this area in the past decade is reflected in the clinical practice of dedicated Brazilian centers.

Contemporary Management Before Chronic Total Occlusion Percutaneous Coronary Interventions: Insights From the Veterans Affairs Clinical Assessment, Reporting, and Tracking Program

BACKGROUND

Guidelines recommend maximal antianginal medical therapy before attempted coronary artery chronic total occlusion (CTO) percutaneous coronary intervention (PCI). The degree to which this occurs in contemporary practice is unknown. We aimed to characterize the frequency and variability of preprocedural use of antianginal therapy and stress testing within 3 months before PCI of CTO (CTO PCI) across a nationally integrated health care system.

METHODS

We identified patients who underwent attempted CTO PCI from January 2012 to September 2018 within the Veterans Affairs Healthcare System. Patients were categorized by management before CTO PCI: presence of ≥2 antianginals, stress testing, and ≥2 antianginals and stress testing within 3 months of PCI attempt. Multivariable logistic regression and inverse propensity weighting were used for adjustment before trimming, with median odds ratios calculated for variability estimates.

RESULTS

Among 4250 patients undergoing attempted CTO PCI, 40% received ≥2 antianginal medications and 24% underwent preprocedural stress testing. The odds of antianginal therapy with more than one medication before CTO PCI did not change over the years of the study (odds ratio [OR], 1.0 [95% CI, 0.97-1.04]), whereas the odds of undergoing preprocedural stress testing decreased (OR, 0.97 [95% CI, 0.93-0.99]), and the odds of antianginal therapy with ≥2 antianginals and stress testing did not change (OR, 0.98 [95% CI, 0.93-1.04]). Median odds ratios (MOR) showed substantial variability in antianginal therapy across hospital sites (MOR, 1.3 [95% CI, 1.26-1.42]) and operators (MOR, 1.35 [95% CI, 1.26-1.63]). Similarly, preprocedural stress testing varied significantly by site (MOR, 1.68 [95% CI, 1.58-1.81]) and operator (MOR, 1.80 [95% CI, 1.56-2.38]).

CONCLUSIONS

Just under half of patients received guideline-recommended management before CTO PCI, with significant site and operator variability. These findings suggest an opportunity to reduce variability in management before CTO PCI.

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.

The challenges of a randomised placebo-controlled trial of CTO PCI vs. placebo with optimal medical therapy: The ORBITA-CTO pilot study design and protocol

Background

Percutaneous coronary intervention (PCI) for coronary chronic total occlusion (CTO) has been performed for the improvement of symptoms and quality of life in patients with stable angina. The ORBITA study demonstrated the role of the placebo effect in contemporary PCI in non-CTO chronic coronary syndromes. However, the benefit of CTO PCI beyond that of a placebo has not been demonstrated.

Aims

The ORBITA-CTO pilot study will be a double-blind, placebo-controlled study of CTO PCI randomising patients who have: (1) been accepted by a CTO operator for PCI; (2) experienced symptoms due to a CTO; (3) evidence of ischaemia; (4) evidence of viability within the CTO territory; and (5) a J-CTO score ≤3.

Methods

Patients will undergo medication optimisation that will ensure they are on at least a minimum amount of anti-anginals and complete questionnaires. Patients will record their symptoms on an app daily throughout the study. Patients will undergo randomisation procedures, including an overnight stay, and be discharged the following day. All anti-anginals will be stopped after randomisation and re-initiated on a patient-led basis during the 6-month follow-up period. At follow-up, patients will undergo repeat questionnaires and unblinding, with a further 2-week unblinded follow-up.

Results

The co-primary outcomes are feasibility (blinding) in this cohort and angina symptom score using an ordinal clinical outcome scale for angina. Secondary outcomes include changes in quality-of-life measures, Seattle Angina Questionnaire (SAQ), peak VO2, and anaerobic threshold on the cardiopulmonary exercise test.

Conclusion

The feasibility of a placebo-controlled CTO PCI study will lead to future studies assessing efficacy. The impact of CTO PCI on angina measured using a novel daily symptom app may provide improved fidelity in assessing symptoms in patients with CTO's.