Update in the Percutaneous Management of Coronary Chronic Total Occlusions

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.

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.

A Novel Strategy for Emergency Treatment of Coronary Perforations by Placing a Drug-Eluting Stent before Sealing off the Leakage with a Covered Stent to Improve Long-Term Outcomes in Patients with Coronary Artery Perforations

We aimed to investigate the safety, feasibility, and long-term results of drug-eluting stent implantation before covered stents for treating coronary artery perforation (CAP). Between 2015 and 2020, 12,733 patients undergoing percutaneous coronary intervention (PCI) were retrospectively analyzed. The primary endpoint was 1-year target lesion revascularization (TLR), whereas secondary endpoints included the rate of major adverse cardiac and cerebrovascular events (MACCE) and all-cause death at 1 year. A total of 159 patients with CAP were identified during the study period, of whom 47.2% (n = 75) were treated with a covered stent (CS group) because of complex and/or severe CAP and 84 (52.8%) without (non-CS group). In the majority of patients, emergency drug-eluting stent placement before covered stent implantation was feasible (n = 69, 82%). There were no significant differences among patients treated with or without a covered stent in terms of primary or secondary clinical endpoints: a similar rate of TLR (18.67% vs. 21.43%, p = 0.6646), MACCE (25.33% vs. 22.62%, p = 0.6887), and 1-year mortality (12.00% vs. 11.90%, p = 0.9853) were identified comparing cases with covered stent implantation and without. In conclusion, our study implicates that the use of covered stents for sealing coronary perforation might not impact the 1-year clinical outcome if used properly. Moreover, the emergent use of drug-eluting stents before covered stent implantation in CAP is a safe and effective method to avoid target lesion revascularization in patients treated with covered stents.

Deep Learning-Based Predictive Model for Revascularization of Chronic Total Occlusions on Angiographic Imaging

Revascularization of chronic total occlusions (CTO) is currently one of the most complex procedures in percutaneous coronary intervention (PCI), requiring the use of specific devices and a high level of experience to obtain good results. Once the clinical indication for extensive ischemia or angina uncontrolled with medical treatment has been established, the decision to perform coronary intervention is not simple, since this procedure has a higher rate of complications than non-PCI percutaneous intervention, higher ionizing radiation doses and a lower success rate. However, CTO revascularization has been shown to be helpful in symptomatic improvement of angina, reduction of ischemic burden, or improvement of ejection fraction. The aim of this work is to determine whether a model developed using deep learning techniques, and trained with angiography images, can better predict the likelihood of a successful revascularization procedure for a patient with a chronic total occlusion (CTO) lesion in their coronary artery (measured as procedure success and the duration of time during which X-ray imaging technology is used to perform a medical procedure) than the scales traditionally used. As a preliminary approach, patients with right coronary artery CTO will be included since they present standard angiographic projections that are performed in all patients and present less technical variability (duration, projection angle, image similarity) among them.The ultimate objective is to develop a predictive model to help the clinician in the decision to intervene and to analyze the performance in terms of predicting the success of the technique for the revascularization of chronic occlusions.Clinical Relevance- The development of a deep learning model based on the angiography images could potentially overcome the gold standard and help interventional cardiologists in the treatment decision for percutaneous coronary intervention, maximizing the success rate of coronary 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.

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.

Computed Tomography Radiomics Model Predicts Procedure Success of Coronary Chronic Total Occlusions

BACKGROUND

Coronary computed tomography (CT) angiography imaging is useful for the preprocedural evaluation of chronic total occlusion (CTO). However, the predictive value of CT radiomics model for successful percutaneous coronary intervention (PCI) has not been studied. We aimed to develop and validate a CT radiomics model for predicting PCI success of CTOs.

METHODS

In this retrospective study, a radiomics-based model for predicting PCI success was developed on the training and internal validation sets of 202 and 98 patients with CTO, collected from 1 tertiary hospital. The proposed model was validated on an external test set of 75 CTO patients enrolled from another tertiary hospital. CT radiomics features of each CTO lesion were manually labeled and extracted. Other anatomical parameters, including occlusion length, entry morphology, tortuosity, and calcification burden, were also measured. Fifteen radiomics features, 2 quantitative plaque features, and CT-derived Multicenter CTO Registry of Japan score were used to train different models. The predictive values of each model were evaluated for predicting revascularization success.

RESULTS

In the external test set, 75 patients (60 men; 65 years [58.5, 71.5]) with 83 CTO lesions were assessed. Occlusion length was shorter (13.00 mm versus 29.30 mm, P=0.007) in PCI success group whereas the presence of tortuous course was more commonly presented in PCI failure group (1.49% versus 25.00%, P=0.004). The radiomics score was significantly smaller in PCI success group (0.10 versus 0.55, P<0.001). The area under the curve of CT radiomics-based model was significantly higher than that of CT-derived Multicenter CTO Registry of Japan score for predicting PCI success (area under the curve=0.920 versus 0.752, P=0.008). The proposed radiomics model accurately identified 89.16% (74/83) CTO lesions with procedure success.

CONCLUSIONS

CT radiomics-based model outperformed CT-derived Multicenter CTO Registry of Japan score for predicting PCI success. The proposed model is more accurate than the conventional anatomical parameters to identify CTO lesions with PCI success.

Patient Selection and Clinical Indication for Chronic Total Occlusion Revascularization-A Workflow Focusing on Non-Invasive Cardiac Imaging

Percutaneous coronary intervention of chronic total occlusion (CTO PCI) is a challenging procedure with high complication rates and, as not yet fully understood long-term clinical benefits. Ischemic symptom relief in patients with high ischemic burden is to date the only established clinical indication to undergo CTO PCI, supported by randomized controlled trials. In this context, current guidelines suggest attempting CTO PCI only in non-invasively assessed viable CTO correspondent myocardial territories, with large ischemic areas. Hence, besides a comprehensive coronary angiography lesion evaluation, the information derived from non-invasive cardiac imaging techniques is crucial to selecting candidates who may benefit from the revascularization of the occluded vessel. Currently, there are no clear recommendations for a non-invasive myocardial evaluation or choice of imaging modality pre-CTO PCI. Therefore, selecting among available options is left to the physician's discretion. As CTO PCI is strongly recommended to be carried out explicitly in experienced centers, full access to non-invasive imaging for risk-benefit assessment as well as a systematic institutional evaluation process has to be encouraged. In this framework, we opted to review the current myocardial imaging tools and their use for indicating a CTO PCI. Furthermore, based on our experience, we propose a cost-effective systematic approach for myocardial assessment to help guide clinical decision-making for patients presenting with chronic total occlusions.

Predicting the Success Rate of Elective Percutaneous Coronary Intervention for Prior Failed Chronic Total Occlusion: a Novel Scoring System

To investigate a scoring system for predicting the risk of successful percutaneous coronary intervention (PCI) after prior failed chronic total occlusion (CTO). Patients with previously attempted CTO-PCI were enrolled in our study retrospectively from January 2016 to December 2019. All clinical and procedural data were collected and analyzed. Univariate and multivariate logistic regression was performed to investigate the predictors of technical success. A total of 194 patients/CTO lesions were studied. The multivariate logistic regression showed that occlusion length < 20 mm (odds ratio (OR) = 2.94, score = 1), non-calcification (OR = 2.93, score = 1), adequate distal landing zone (OR = 4.46, score = 1), Rentrop grade ≥ 2 (OR = 5.98, score = 1), and retrograde approach as the initial strategy (OR = 10.28, score = 2) were predictors of the success of re-attempt PCI. The technical success rate for scores from 0 to ≥ 4 were 0%, 17.9%, 46.2%, 77.8%, and 93.3% respectively. Our scoring system can be used to predict the success rate of re-attempt CTO-PCI.

Clinical Outcomes of Drug-Coated Balloon Treatment After Successful Revascularization of de novo Chronic Total Occlusions

Background

The safety and efficacy of drug-coated balloon (DCB) treatment for de novo coronary chronic total occlusion (CTO) remain uncertain. The aim of this study was to evaluate the outcomes of DCB only treatment for de novo CTO.

Methods

In this retrospective study, 101 vessels with de novo CTO lesions dilated by balloon angioplasty with thrombolysis in myocardial infarction flow grade 3 were included. Among them, 93 vessels successfully treated with DCB only treatment were analyzed. The study endpoint was major adverse cardiac events (MACE) at 2 years, a composite of cardiac death, non-fatal myocardial infarction (MI), target vessel revascularization (TVR), and target vessel thrombosis. The secondary endpoint was late lumen loss (LLL) on follow-up coronary angiography.

Results

All 84 patients were followed up clinically, and 67 vessels underwent scheduled coronary angiography after 6 months. There were no procedural complications, and three vessels required bailout-stenting. The median follow-up was 720 days (interquartile range [IQR]; 406–1,268 days). MACE occurred in 8.3% of the patients after 1 year, including cardiac death (1.2%), TVR (7.1%), and no non-fatal MI and target vessel thrombosis. Two years after treatment, MACE occurred in 16.7% of the patients, including cardiac death (2.4%), non-fatal MI (3.6%), TVR (13.1%), and no target vessel thrombosis. The mean LLL was 0.03 ± 0.53 mm. Binary restenosis occurred in 14.9% of the treated vessels, and 3.0% of the vessels had late re-occlusion on follow-up coronary angiography.

Conclusions

If the result of revascularization using balloon angioplasty is good, the clinical outcomes of DCB only treatment of de novo CTOs at the 2-year follow-up are encouraging, with a low rate of hard endpoints and acceptable MACE rates (Clinical Trial Registration Information; Impact of Drug-coated Balloon Treatment in de novo Coronary Lesion; NCT04619277).

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.

CTO in Contemporary PCI

Percutaneous Coronary Intervention (PCI) of Chronic Total Occlusions (CTO) represents the most challenging procedure in modern endovascular treatments. In recent years, the success rate of CTO PCI has substantially improved, owing to increasing operator expertise and advancements in CTO equipment and algorithms as well as the development of expert consensus documents. In this review, we summarize existing evidence for CTO PCI, its success/ risk prediction scoring tools, procedural principles and complications and provide an insight into the future role of CTO PCI.

Contemporary Strategies and Outcomes of Dedicated Chronic Total Occlusion Percutaneous Coronary Intervention Programs: A Prospective Multicentre Registry

Background

The field of CTO PCI is expanding, but successful and safe percutaneous coronary intervention (PCI) of coronary chronic total occlusions (CTO) requires a substantial resource and experience investment. We aimed to assess temporal trends in strategies and outcomes of 2 dedicated programs for CTO PCI.

Methods

Between 2011 and 2020, 920 CTO PCI procedures were prospectively included at 2 referral centres in Belgium. Temporal trends were assessed, and logistic regression models were built to identify predictors of outcome.

Results

Despite an increase in lesion complexity (the J-CTO score increased from 1.3 in year 1 to 1.7–2.0 in years 8-9, p < 0.001), technical success improved from 70.0% to 85.6% in year 9 (p value for trend <0.001). We observed the most significant improvement starting at years 3-4 (OR 2.3 in year 4 versus year 1, p=0.018). Together with an increase in success rates and lesions complexity, there was an increase in the use of dual injections, retrograde approaches, the number of balloons and stents, and the use of microcatheters. Conversely, there was a decrease in large bore access, an increase in radial approach, and a shift towards contemporary dissection/reentry techniques. This strategy resulted in a stable major complication rate of 4.7% (p value for trend 0.33). The rate of coronary procedure-related myocardial injury was high (71.0%) and was associated with the use of more intracoronary devices.

Conclusions

Three to four years after initiation of a dedicated CTO PCI program with 50 CTO PCIs per year, consistent high technical success and low complication rates are achieved using contemporary strategies.

Clinical Outcomes following Large Vessel Coronary Artery Perforation Treated with Covered Stent Implantation: Comparison between Polytetrafluoroethylene- and Polyurethane-Covered Stents (CRACK-II Registry)

Data on the clinical outcomes comparing synthetic fluorocarbon polymer polytetrafluoroethylene- (PTFE, GraftMaster) and polyurethane- (Papyrus) covered stents (CSs) to seal coronary artery perforations (CAPs) are limited. We aimed to evaluate 30-day and 1-year clinical outcomes after PCI complicated by CAP and treated with CS. We assessed 106 consecutive patients with successful CAP sealing (122 CSs): GraftMaster (51 patients, 57 CSs) or Papyrus CS (55 patients, 65 CSs). The primary endpoint was the occurrence of major adverse cardiac events (MACE), defined as the composite of cardiac death, target lesion revascularisation (TLR), and myocardial infarction (MI). The mean age of subjects was 69 ± 9.6 years (53.8% males). No significant differences were identified between the GraftMaster and Papyrus groups at the 30-day follow-up for MACE, cardiac death, MI and stent thrombosis (ST), while significantly lower rate of TLR and TVR (p = 0.02) were confirmed in the Papyrus group. At one year, differences remained similar between stents for MACE, a trend towards a lower rate of TLR (p = 0.07), MI (p = 0.08), and ST (p = 0.08), and higher for cardiac death (p = 0.07) was observed in the Papyrus group. This real-life registry of CAP illustrated that the use of Papyrus CS is associated with lower rates of TLR and TVR at 30-day follow-up in comparison to the GraftMaster CSs and no significant differences between both assessed CS at one year of follow-up.

A Clinical Score to Predict "Corrected Thrombolysis in Myocardial Infarction Frame Count" in Patients With ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

Corrected thrombolysis in myocardial infarction frame count (cTFC) is an objective, simple, and reproducible method to assess coronary blood flow which is a surrogate for cardiovascular outcomes. It is important to learn which factors are associated with cTFC. The goal of this study was to determine predictive models for epicardial blood flow assessed by cTFC and develop a diagnostic predictive model that indicates the individualized assessment of epicardial blood flow prior to primary percutaneous coronary intervention. This is a retrospective study including 3205 patients with ST-segment elevation myocardial infarction who underwent pPCI. The primary outcome was cTFC. Multivariable linear regression analysis was performed. Subsequently, a nomogram was developed to predict cTFC according to the candidate predictors. Median age was 58; the number of male patients was 2381 (74.3%). Median value of cTFC was 22 and interquartile range (IQR): 16.5-28.0). Age, diabetes mellitus (DM), total ischemic time, systolic blood pressure (SBP), heart rate (HR), and history of statin use remained in both full and reduced models. Our model may potentially allow clinicians to identify patients at high risk for impaired epicardial perfusion.

Percutaneous coronary intervention of totally occluded coronary venous bypass grafts: An exercise in futility?

BACKGROUND

Percutaneous coronary intervention (PCI) of diseased saphenous vein grafts (SVG) continues to pose a clinical challenge. Current PCI guidelines give a class III recommendation against performing PCI on chronically occluded SVG. However, contemporary outcomes after SVG intervention have incrementally improved with distal protection devices, intracoronary vasodilators, drug-eluting stents, and prolonged dual antiplatelet therapy.

AIM

To reassess the procedural and long-term outcomes of PCI for totally occluded SVG with contemporary techniques.

METHODS

This was a retrospective observational study conducted at a single university hospital. The study population consisted of 35 consecutive patients undergoing PCI of totally occluded SVG. Post-procedure dual antiplatelet therapy was continued for a minimum of one year and aspirin was continued indefinitely. Clinical outcomes were assessed at a mean follow-up of 1221 ± 1038 d. The primary outcome was freedom from a major adverse cardiac event (MACE) defined as the occurrence of any of the following: death, myocardial infarction, stroke, repeat bypass surgery, repeat PCI, or graft reocclusion.

RESULTS

The study group included 29 men and 6 women with a mean age of 69 ± 12 years. Diabetes was present in 14 (40%) patients. All patients had Canadian Heart Classification class III or IV angina. Clinical presentation was an acute coronary syndrome in 34 (97%) patients. Mean SVG age was 12 ± 5 years. Estimated duration of occlusion was acute (< 24 h) in 34% of patients, subacute (> 24 h to 30 d) in 26%, and late (> 30 d) in 40%. PCI was initially successful in 29/35 SVG occlusions (83%). Total stent length was 52 ± 35 mm. Intraprocedural complications of distal embolization or no-reflow occurred in 6 (17%) patients. During longer term follow-up, MACE-free survival was only 30% at 3 years and 17% at 5 years.

CONCLUSION

PCI of totally occluded SVG can be performed with a high procedural success rate. However, its clinical utility remains limited by poor follow-up outcomes.

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".

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Procedural and 1-year outcomes following large vessel coronary artery perforation treated by covered stents implantation: Multicentre CRACK registry

Background

Data regarding the clinical outcomes of covered stents (CSs) used to seal coronary artery perforations (CAPs) in the all-comer population are scarce. The aim of the CRACK Registry was to evaluate the procedural, 30-days and 1-year outcomes after CAP treated by CS implantation.

Methods

This multicenter all-comer registry included data of consecutive patients with CAP treated by CS implantation. The primary endpoint was the composite of major adverse cardiac events (MACEs), defined as cardiac death, target lesion revascularization (TLR), and myocardial infarction (MI).

Results

The registry included 119 patients (mean age: 68.9 ± 9.7 years, 55.5% men). Acute coronary syndrome, including: unstable angina 21 (17.6%), NSTEMI 26 (21.8%), and STEMI 26 (21.8%), was the presenting diagnosis in 61.3%, and chronic coronary syndromes in 38.7% of patients. The most common lesion type, according to ACC/AHA classification, was type C lesion in 47 (39.5%) of cases. A total of 52 patients (43.7%) had type 3 Ellis classification, 28 patients (23.5%) had type 2 followed by 39 patients (32.8%) with type 1 perforation. Complex PCI was performed in 73 (61.3%) of patients. Periprocedural death occurred in eight patients (6.7%), of which two patients had emergency cardiac surgery. Those patients were excluded from the one-year analysis. Successful sealing of the perforation was achieved in 99 (83.2%) patients. During the follow-up, 26 (26.2%) patients experienced MACE [7 (7.1%) cardiac deaths, 13 (13.1%) TLR, 11 (11.0%) MIs]. Stent thrombosis (ST) occurred in 6 (6.1%) patients [4(4.0%) acute ST, 1(1.0%) subacute ST and 1(1.0%) late ST].

Conclusions

The use of covered stents is an effective treatment of CAP. The procedural and 1-year outcomes of CAP treated by CS implantation showed that such patients should remain under follow-up due to relatively high risk of MACE.

Preprocedural computed tomography angiography in differentiating chronic total from subtotal coronary occlusions

INTRODUCTION

Differentiation of chronic total occlusion (CTO) from subtotal coronary occlusions (STOs) is often difficult to make from coronary angiography. These differences are very important, as the technical expertise and tools required are significantly different for revascularization of these lesions. We sought to determine if preprocedural computed tomography angiography (CTA) can help better diagnose and differentiate CTO from STO.

METHODS

We searched three databases (Ovid MEDLINE, EMBASE, EBM reviews) from 1 January 1946 to 1 March 2019. Studies reporting on the use of computed tomography (CT) to aid in CTO revascularization were included. Case reports and case series were excluded.

RESULTS

We identified 577 articles, and using the Preferred Reporting Items for Systematic Reviews and Meta-analyses method, 4 articles met prespecified inclusion criteria. A total of 669 patients were included. The statistically significant CT-derived parameters determined to help differentiate CTO from STO were found to include longer lesion length (four out of four studies), larger contrast density difference (one out of four studies), presence of collaterals (two out of four studies) and the presence of the reverse attenuation gradient sign (two out of four studies).

CONCLUSION

This systematic review shows the utility of preprocedural CTA to help differentiate CTO from STO using a number of CT-derived parameters as above. Further, this study highlights the need for further research to develop specific validated parameters for differentiation of CTO and STO.

Complications and failure modes of covered coronary stents: Insights from the MAUDE database

BACKGROUND

Data on the mechanisms of failure of covered coronary stents [Graftmaster, PK Papyrus] are limited.

METHODS

We queried the "Manufacturer and User Facility Device Experience" (MAUDE) database between August 2018 (when the PK Papyrus stent was FDA approved) and December 2020 for reports on covered coronary stents.

RESULTS

We identified 299 reports in the MAUDE database (after excluding duplicates, peripheral vascular reports, and incomplete records) (Graftmaster n = 225, PK Papyrus n = 74). The most common mechanism of failure of covered stents was failure to deliver the stent (46.2%), followed by stent dislodgement (22.4%) and failure to seal the perforation (19.7%). Failure to deliver the stent was more often reported with Graftmaster compared with PK Papyrus (59.1% vs. 6.8%, p < 0.001). Stent dislodgement was more often reported with PK Papyrus compared with Graftmaster (75.7% vs. 4.9%, p < 0.001) and was managed by device retrieval or by crushing the stent.

CONCLUSIONS

The most common failure mechanisms of covered stents are failure of delivery, stent dislodgement, and failure to seal the perforation. Failure of delivery was more common with Graftmaster, while stent dislodgement was more common with PK Papyrus. Further improvements in covered stent design are needed to optimize deliverability and minimize the risk of complications.

Choice of CTO scores to predict procedural success in clinical practice. A comparison of 4 different CTO PCI scores in a comprehensive national registry including expert and learning CTO operators

BACKGROUND

We aimed to compare the performance of the recent CASTLE score to J-CTO, CL and PROGRESS CTO scores in a comprehensive database of percutaneous coronary intervention of chronic total occlusion procedures.

METHODS

Scores were calculated using raw data from 1,342 chronic total occlusion procedures included in REBECO Registry that includes learning and expert operators. Calibration, discrimination and reclassification were evaluated and compared.

RESULTS

Mean score values were: CASTLE 1.60±1.10, J-CTO 2.15±1.24, PROGRESS 1.68±0.94 and CL 2.52±1.52 points. The overall percutaneous coronary intervention success rate was 77.8%. Calibration was good for CASTLE and CL, but not for J-CTO or PROGRESS scores. Discrimination: the area under the curve (AUC) of CASTLE (0.633) was significantly higher than PROGRESS (0.557) and similar to J-CTO (0.628) and CL (0.652). Reclassification: CASTLE, as assessed by integrated discrimination improvement, was superior to PROGRESS (integrated discrimination improvement +0.036, p<0.001), similar to J-CTO and slightly inferior to CL score (- 0.011, p = 0.004). Regarding net reclassification improvement, CASTLE reclassified better than PROGRESS (overall continuous net reclassification improvement 0.379, p<0.001) in roughly 20% of cases.

CONCLUSION

Procedural percutaneous coronary intervention difficulty is not consistently depicted by available chronic total occlusion scores and is influenced by the characteristics of each chronic total occlusion cohort. In our study population, including expert and learning operators, the CASTLE score had slightly better overall performance along with CL score. However, we found only intermediate performance in the c-statistic predicting chronic total occlusion success among all scores.

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

OBJECTIVES

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Clinical Outcomes in Chronic Total Occlusion Revascularization Versus No Chronic Total Occlusion Revascularization: Variability by Target Vessel

We aimed to investigate the impact of target vessel on clinical outcomes in chronic total occlusion (CTO) revascularization versus no CTO revascularization. This multicenter, retrospective, cohort study involves patients with ≥1 CTO. After classification based on different CTO target vessels or multiple CTOs, patients were further categorized as the CTO revascularization group and the no CTO revascularization group based on treatment received. The primary outcome was a composite of death, myocardial infarction, stroke, repeated revascularization, and hospital admission due to ischemic symptoms. From August 2016 to August 2017, 1712 eligible patients were consecutively enrolled. Chronic total occlusion revascularization was associated with lower risk of 1-year major adverse cardiovascular and cerebrovascular events (MACCEs; adjusted hazard ratio [HR]: 0.36; 95% CI: 0.20-0.67; P = .001) compared with no CTO revascularization in left anterior descending (LAD) CTO patients. The benefit of CTO revascularization was not evident among those with left circumflex (LCX; adjusted HR: 0.51; 95% CI: 0.23-1.10; P = .087), right coronary artery (RCA; adjusted HR: 1.17; 95% CI: 0.59-2.33; P = .648), and multiple CTOs (adjusted HR: 1.00; 95% CI: 0.41-2.44; P = .994). Revascularization for LAD CTO, but not LCX, RCA, or multiple CTOs, was associated with lower risk of 1-year MACCEs compared with no CTO revascularization.

A contemporary review of clinical significances of percutaneous coronary intervention for chronic total occlusions, with some Japanese insights

The clinical "significance" of percutaneous coronary intervention for coronary chronic total occlusion (CTO-PCI) has been evaluated. In the beginning, the effects on clinical endpoints were investigated by comparisons between cases of success and failure of CTO-PCI, which mostly demonstrated better long-term outcomes in the successful cases. Similarly, improvement of cardiac function or wall motion was proven by serial observational studies. Accordingly, several prospective randomized trials (RCTs), which should confirm such accumulated potential benefits, were recently conducted by comparison with studies of patients that had received optical medical therapy (OMT) alone. While they mostly demonstrated significant improvement of angina symptoms and quality of life (QOL) in the CTO-PCI group, they failed to prove a reduction of clinical events or improvement of left ventricle wall motion, compared with OMT. Concurrent guidelines or consensus documents emphasize that the principal indication for CTO-PCI is to improve symptoms. To determine strategy, the following must be discussed in each individual case: the probability of procedural success, the expectation of long-term patency, and an assessment of the balance between procedure-related complications and overall benefits. In essence, we believe the following facts to be the current sincere appraisal of CTO-PCI: (1) improvements of symptoms and QOL are established, but the others remain inconclusive, and; (2) their margins for improvement are narrowing and numbers of candidates are shrinking. Precision medicine or individualization may be the right directions to take, to enhance the potential of this treatment. This course of action demands discrimination of those candidates who will truly receive benefits from invasive treatment, and that still requires further clinical studies or actions.

Innovative transcatheter procedures for the treatment of heart failure

The prevalence of heart failure (HF) continues to rise over time, with aging of the population and increased survival of incident cases. Major improvements occurred in drug therapy but morbidity and mortality of HF patients remain high. Some non-pharmacologic approaches to HF are already part of standard treatment for HF, including implantable cardioverter-defibrillators, cardiac resynchronization therapy (CRT) and left ventricular assist devices (LVADs). A number of transcatheter treatments and devices have been developed to improve management of valvular heart diseases (VHD), and some of them are being used or tested in specific HF conditions. For example, transcatheter aortic valve implantation (TAVI) to unload the left ventricle in patients with moderate aortic stenosis (AS) and HF or TAVI for severe aortic regurgitation (AR) in patients with LVADs. Similarly, percutaneous mitral valve repair can be used to improve prognosis and quality of life in patients with functional mitral valve regurgitation, and has been proposed as a bridge-to-LVAD or to heart transplant in selected patients. Other devices have been specifically developed for the treatment of chronic HF. In this review we describe the main devices used in the treatment of HF associated with aortic and mitral valve disease, as well as novel transcatheter interventions for chronic HF with different pathophysiologic targets.

Development and validation of a prediction model for angiographic perforation during chronic total occlusion percutaneous coronary intervention: OPEN-CLEAN perforation score

BACKGROUND

Perforation is the most frequent complication of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) and is associated with adverse events including mortality.

METHODS

Among 1,000 consecutive patients enrolled in 12 center prospective CTO PCI study (OPEN CTO), all perforations were reviewed by the angiographic core-lab. Eighty-nine patients (8.9%) with angiographic perforation were compared to 911 patients without perforation. We sought to describe the clinical and angiographic predictors of angiographic perforation during CTO PCI and develop a risk prediction model.

RESULTS

Among eight clinically important candidate variables, independent risk factors for perforation included prior CABG (OR 2.0 [95% CI, 1.2-3.3], p < .01), occlusion length (OR 1.2 per 10 mm increase [95% CI, 1.1-1.3], p < .01), ejection fraction (OR 1.2 per 10% decrease [95% CI, 1.1-1.5], p < .01), age (OR 1.3 per 5 year increase [95%CI, 1.1-1.5], p < .01), and heavy calcification (OR 1.7 [95% CI, 1.0-2.7], p = .04). Three other potential candidate variables, glomerular filtration rate, proximal cap ambiguity, and target vessel, were not independently associated with perforation. The model was internally validated using bootstrapping methods. From the full model, a simplified perforation prediction score (OPEN-CLEAN score: CABG, Length [occlusion], EF < 50%, Age, CalcificatioN) was developed, which discriminated the risk of angiographic perforation well (c-statistics = 0.75) and demonstrated good calibration.

CONCLUSION

This simple 5-variable prediction score may help CTO operators to risk-stratify patients for angiographic perforation using variables available prior to CTO PCI procedures.

A sex-stratified long-term clinical outcome analysis in coronary chronic total occlusion patients

Background

Differences in outcomes for women and men after percutaneous coronary intervention (PCI) in chronic total occlusion (CTO) patients remain controversial. Herein, we compared the clinical outcomes by sex in CTO patients undergoing PCI.

Methods

A total of 563 consecutive patients (19% women) who were diagnosed with CTO at a single center in China from June 2017 to December 2019 were included in this study. Three hundred patients were revascularized by PCI, and 263 were not revascularized. The clinical outcomes of these patients stratified by sex were examined. The primary endpoints included the risk of major adverse cardiovascular and cerebrovascular events (MACCE); the secondary endpoint was cardiac death; hazard ratios were generated using multivariable Cox regression.

Results

Women represented 19% of the cohort (107/563 patients). Women have lower mean body mass index (BMI) and abdominal circumference compared with men; however, the proportion of hypertension, diabetes, and previous coronary heart disease is higher in female patients. At 2-year follow-up, there were no differences between men and women for MACCE (15.8% vs 20.6%, p = 0.234) and cardiac death (3.1% vs 5.6%, p = 0.202). Predictors of CTO recanalization revealed that age < 65 years, absence of prior CABG, no history of DM, and non-triple vessel were predictors of CTO recanalization. Sex did not predict recanalization in this regression model. Successful CTO PCI was associated with reduced MACCE.

Conclusion

Our study suggests an equal benefit of CTO recanalization with a marked reduction in MACCE in women and men alike. Further dedicated studies are needed to confirm these findings.

Chronic total occlusion percutaneous coronary intervention: managing perforation complications

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Subintimal Plaque Modification and Subintimal Dissection and Reentry: Strategies to Turn Failure into Success

The success of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) depends on the execution of bailout strategies, like subintimal dissection and reentry (STAR) and subintimal plaque modification (SPM). These are invaluable when traditional techniques fail. SPM is a modification of the STAR technique in which angioplasty is performed of the occluded segment without true lumen access in the distal vessel. Available data on SPM has shown favorable outcomes with a greater than 90% success rate when the failed CTO is reattempted in 8-12 weeks after SPM has been performed. Future studies are needed to better assess its role.

The efficacy and safety of transradial and transfemoral approach in treatment of coronary chronic total occlusion: a systematic review and meta-analysis

BACKGROUND

The clinical efficacy and safety of transradial (TR) percutaneous coronary intervention (PCI) in comparison to transfemoral (TF) for chronic total occlusion (CTO) is not well studied in literature. Objectives: We sought to study the outcome and complications associated with TR compared with TF for CTO interventions.

METHODS

After a systematic literature search was done in PubMed and EMBASE, we performed a meta-analysis of studies comparing TF and TR for CTO PCI. Results: Twelve studies with 19,309 patients were included. Compared to those who has TF access, individuals who were treated via TR approach had statistically significant lower access complication rates [odds ratio (OR): 0.33; 95% confidence interval (CI): 0.22 to 0.49; p < 0.0001]. The procedural success was in the favor of TR method (OR: 1.4; 95% CI: 1.31-1. 51; p < 0.0001). The incidence of major adverse cardiovascular and cerebrovascular events (MACCE) and contrast-induced nephropathy were similar in both groups.

CONCLUSION

When compared with TF access interventions in CTO PCI; the TR approach appears to be associated with far less access-site complications, higher procedural success, and comparable MACCE.

Latest developments in chronic total occlusion percutaneous coronary intervention

INTRODUCTION

Chronic Total Occlusion Percutaneous Coronary Intervention (CTO PCI) is now performed with high success rates and acceptable complication rates.

AREAS COVERED

We describe recent clinical and technological developments in CTO PCI from 2018 to 2020.

EXPERT OPINION

After publication of six randomized controlled trials, improving patient symptoms remains the principal indication for CTO PCI. Although good outcomes can be achieved with CTO PCI at experienced centers, success rates are significantly lower at less experienced centers, despite increased use in CTO crossing algorithms and development of novel and improved equipment and techniques.

Equipment utilization in chronic total occlusion percutaneous coronary interventions: Insights from the PROGRESS-CTO registry

BACKGROUND

We examined guidewire and microcatheter utilization during chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

METHODS

We examined device utilization in 2,968 CTO PCIs performed in 2,936 patients at 19 US and two international center between January 2016 and January 2019.

RESULTS

The median number of antegrade guidewires used per case declined (5 in 2016 vs 3 in 2019) and was higher in higher complexity lesions (2 in J-CTO 0 vs. 8 in J-CTO 4 or 5 score). In antegrade-only procedures, the most frequently used guidewires were the Pilot 200 (Abbott Vascular, 37%), Fielder XT (Asahi Intecc, 25%) and Gaia third (Asahi Intecc, 18%), while the most commonly used microcatheters were the Turnpike Spiral (Vascular Solutions, 18%) and Turnpike (Vascular Solutions, 16%). Compared with 2012-2015, during 2016-2019 use of novel equipment such as the Gaia guidewires and the Turnpike microcatheters led to decreased use of Confianza Pro 12 (Asahi Intecc) wire and Corsair (Asahi Intecc) family of microcatheters. In retrograde cases, the guidewires most commonly used were the Sion (44%), Pilot 200 (27%) and Fielder FC (26%), while the Corsair/Corsair Pro, Turnpike LP (Vascular Solutions) and Caravel (Asahi Intecc) were the most frequently used microcatheters for collateral crossing (29%, 26% and 22%, respectively).

CONCLUSIONS

The most commonly used guidewires during CTO PCI are polymer-jacketed guidewires and the most commonly used microcatheters are torquable microcatheters.

Impact of coronary collateralization on long-term clinical outcomes in type 2 diabetic patients after successful recanalization of chronic total occlusion

Background

To assess the prognostic role of coronary collaterals in patients with type 2 diabetes mellitus (T2DM) after successful percutaneous coronary intervention (PCI) for chronic total occlusion (CTO).

Methods

Coronary collateralization was graded according to Rentrop scoring system in 198 type 2 diabetic patients and 335 non-diabetics with stable angina undergoing PCI for at least one CTO lesion. Left ventricular ejection fraction (LVEF) was determined and major adverse cardio-cerebral events (MACCE) were recorded during follow-up.

Results

Poor collateralization was more common in patients with T2DM than in non-diabetics (40% vs 29%, p = 0.008). At 13.5 ± 4.1 months, the rate of composite MACCE (17.3% vs 27.6%, p = 0.034) and repeat revascularization (15.2% vs 25.5%, p = 0.026) was lower and the increase in LVEF (3.10% vs 1.80%, p = 0.024) was greater in patients with good collaterals than in those with poor collaterals for non-diabetic group. The associations were in the same direction for T2DM group (35% vs 44%; 30% vs 36%; 2.14% vs 1.65%, respectively) with a higher all-cause mortality in diabetic patients with poor collaterals (p = 0.034). Multivariable Cox proportional hazards analysis showed that coronary collateralization was an independent factor for time to MACCE (HR 2.155,95% CI 1.290–3.599, p = 0.003) and repeat revascularization (HR 2.326, 95% CI 1.357–3.986, p = 0.002) in non-diabetic patients, but did not enter the model in those with T2DM.

Conclusions

T2DM is associated with reduced coronary collateralization. The effects of the status of coronary collateralization on long-term clinical outcomes and left ventricular function appear to be similar in size in type 2 diabetic patients and non-diabetics after successful recanalization of CTO.

Advances in the treatment of coronary perforations

Coronary artery perforation is an infrequent, but potentially life-threatening complication of percutaneous coronary intervention. There are four types of coronary perforation: (a) large vessel; (b) distal vessel; (c) septal collateral; and (d) epicardial collateral perforation. Implantation of a covered stent is the cornerstone of large vessel perforation treatment and can be used in some distal vessel perforations, when embolization is not feasible. Until now the only available covered stent in the US was the Graftmaster stent (two bare metal stents with a PTFE membrane in-between them), that has high profile and is challenging to deliver and expand. Use of the Graftmaster has been associated with high rates of in-stent restenosis and stent thrombosis. Availability of more deliverable covered stents, such as the BeGraft (Bentley InnoMed GmbH, Hechingen, Germany) and PK Papyrus (BIotronik, Lake Oswego, Oregon, that recently received FDA approval) will greatly facilitate treatment of large vessel coronary perforations.

LncRNA-LUNAR1 Levels Are Closely Related to Coronary Collaterals in Patients with Chronic Total Coronary Occlusion

Coronary collaterals can effectively improve myocardial blood supply to the area of CTO (chronic total coronary occlusion) and can, thus, reduce infarct size. LUNAR1(leukemia-induced noncoding activator RNA-1) is a specific LncRNA regulated by Notch signaling that not only can enhance the expression of IGFR-1 but also can promote angiogenesis and cell survival. Here, we investigated the relationship between LncRNA-LUNAR1 levels in peripheral plasma and the formation of coronary collaterals. In total, 172 patients with CTO were enrolled and followed up for 12 months. Coronary collaterals were scored according to the Rentrop scoring system. Preclinical tests of tube formation were used to address the mechanisms behind the association between LncRNA-LUNAR1 and development of collaterals. Clinical data and inflammatory factors, including comorbidity, CD14⁺⁺CD16^- monocytes, and CCL2 (chemokine motif ligand 2), were compared and analyzed. Real-time PCR was used to detect the expression of LncRNA-LUNAR1 in peripheral blood plasma. The Rentrop score was positively correlated with LncRNA-LUNAR1 levels in patients with CTO (R = 0.47, p < 0.001). Tube formation assay proved the direct association between LncRNA-LUNAR1 and development of collaterals (p = 0.011). The univariate Kaplan-Meier analysis revealed that patients with low LncRNA-LUNAR1 expression exhibited worse clinical outcomes than those with high LncRNA-LUNAR1 levels (p = 0.008). Receiver operating characteristic (ROC) curve and correlation analysis further confirmed that LncRNA-LUNAR1 expression was closely related to chronic inflammatory diseases, especially diabetes (area = 0.644, p = 0.001; 95% CI, 0.562-0.726). Furthermore, both CD14⁺⁺CD16^- monocytes (r = - 0.37; p < 0.001) and CCL2 levels (r = - 0.35; p < 0.001) negatively affected the expression of LncRNA-LUNAR1. LncRNA-LUNAR1 expression was positively correlated with coronary collaterals in patients with CTO. Inflammatory factors, including CD14⁺⁺CD16^- monocytes and CCL2, may be risk factors affecting LncRNA-LUNAR1 expression.

Chronic total occlusion percutaneous coronary intervention in Latin America

OBJECTIVES

To report clinical, angiographic characteristics, outcomes, and predictors of unsuccessful procedures in patients who underwent chronic total occlusion (CTO) percutaneous coronary interventions (PCI) in Latin America.

BACKGROUND

CTO PCI has been increasingly performed worldwide, but there is a lack of information in this region.

METHODS

An international multicenter registry was developed to collect data on CTO PCI performed in centers in Latin America. Patient, angiographic, procedural and outcome data were evaluated. Predictors of unsuccessful procedures were assessed by multivariable analysis.

RESULTS

We have included data related to 1,040 CTO PCIs performed in seven countries in Latin America (Argentina, Brazil, Chile, Colombia, Ecuador, Mexico, and Puerto Rico). The mean age was 64 ± 10 years, and CTO PCI was performed mainly for angina control (81%) or treatment of a large ischemic area (30%). Overall technical success rate was 82.5%, and it was achieved with antegrade wire escalation in 81%, antegrade dissection/re-entry in 8% and with retrograde techniques in 11% of the successful procedures. Multivariable analysis identified moderate/severe calcification, a blunt proximal cap and a previous attempt as independent predictors of unsuccessful procedures. In-hospital major adverse cardiovascular events (MACE) occurred in 3.1% of the cases, death in 1% and cardiac tamponade in 0.9% CONCLUSIONS: CTO PCI in Latin America has been performed mainly for ischemia relief. Procedures were associated with a success rate above 80% and low incidence of MACE. Predictors of unsuccessful procedures were similar to those previously reported in the literature.

Thirty-Day Readmissions After Chronic Total Occlusion Percutaneous Coronary Intervention in the United States: Insights From the Nationwide Readmissions Database

BACKGROUND

Several studies have investigated early readmissions after percutaneous coronary interventions (PCIs). However, studies investigating 30-day readmission following PCI for chronic total occlusion (CTO) are lacking.

METHODS

The National-Readmission-Database (NRD) was queried to identify patients undergoing elective CTO PCI between January 1, 2016 and December 31, 2016. We assessed the incidence, predictors, and cost of 30-day readmissions.

RESULTS

A total of 30,579 CTO PCIs were identified in the NRD. After excluding patients who had acute myocardial infarction (n = 14,852), the final cohort included 15,907 patients. In this group of patients, 254 patients (1.5%) expired during their index admission and, 1600 patients (10%) had an unplanned readmission within 30 days. Cardiac causes constituted 54.2% of all causes of readmission. During the readmission, 15.8% of patients had coronary angiography, 8.4% underwent PCI, and 0.9% underwent bypass grafting. Independent predictors of 30-day readmission included baseline characteristics [age (OR 0.99, 95%CI 0.98-0.99), female (OR 1.14, 95%CI 1.01-1.28), lung disease (OR 1.36, 95%CI 1.20-1.55), heart failure (OR 1.42, 95%CI 1.24-1.62), anemia (OR 1.30, 95%CI 1.12-1.50), vascular disease (OR 1.18, 95%CI 1.03-1.35), history of stroke (OR 1.50, 95%CI 1.28-1.76) and the presence of a defibrillator (OR 1.68, 95%CI 1.39-2.03)], and procedural complications [acute kidney injury (OR 1.55, 95%CI 1.33-1.80) and gastrointestinal bleeding (OR 1.67, 95%CI 1.03-2.71)].

CONCLUSIONS

One-tenth of patients undergoing CTO PCI are readmitted within 30-days, mostly for cardiac causes. The majority undergo angiography but <10% receive revascularization. Certain patient and procedural characteristics independently predicted 30-day readmission.

Percutaneous Coronary Intervention Offers Survival Benefit to Stable Patients With One Single Chronic Total Occlusion and Diabetes: A Propensity Score-Matched Analysis

Studies on chronic total occlusion (CTO) treatment strategy in stable patients have reported conflicting results. We focused on stable diabetic patients with a single CTO (other vessels have been successfully treated before). We attempted to identify which strategy (percutaneous coronary intervention [PCI] or medical therapy [MT]) is optimal; 545 patients were selected from a total of 39 952 patients. Based on the initial treatment strategy, we assigned patients to either the PCI or MT group. The primary end point was a major adverse cardiac event (MACE). After a median follow-up of 45 months (interquartile range: 25.7-79.2 months), we observed (1) no difference in MACE and myocardial infarction between groups, (2) multivariate analysis showed that PCI group was superior to MT group in cardiac death (hazard ratio: 4.758 (1.698-13.334); P = .003) and all-cause death (2.767 [1.157-6.618]; P = .022). The superiority was consistent in propensity score-matched analysis, and (3) a failed PCI group was not associated with higher risks in the clinical end points, except for target vessel revascularization, compared with MT. We concluded that for stable patients with diabetes and one single CTO, initial PCI strategy tended to offer patients survival benefits compared with MT.

Conventional vascular access site approach versus fully trans-wrist approach for chronic total occlusion percutaneous coronary intervention: a multicenter registry

OBJECTIVES

To evaluate the incidence of vascular complication and major bleeding in patients undergoing chronic total occlusion (CTO) percutaneous coronary intervention (PCI) with a fully trans-wrist access (TWA) approach versus a conventional approach based on trans-femoral access (TFA).

BACKGROUND

TFA is the preferred vascular access in CTO PCI, but it has been associated with a non-negligible risk of complications.

METHODS

This retrospective registry included all patients undergoing CTO PCI at five institutions between July 2011 and October 2018. Patients were divided into two groups: Conventional (patients treated with at least one TFA) and Fully TWA (subjects exclusively treated with one or two TWA). The primary safety endpoint was a composite of vascular complications and major bleeding. The primary efficacy endpoint was procedural success.

RESULTS

We included 1,900 patients (Conventional n = 1,496 and Fully TWA n = 404). Conventional patients showed higher occlusion complexity (J-CTO score 2.1 ± 1.2 vs. 1.5 ± 1.1, p < .001). Procedural success showed no significant difference between both groups (85.7 vs. 83.0%, p = .17). The primary safety endpoint occurred more frequently in the Conventional group (10.3 vs. 4.5%, p < .001), driven by vascular complications (9.4 vs. 3.7%, p < .001). On multivariate analysis, not using a Fully TWA approach was an independent predictor of the study endpoint, after adjusting for age, sex, diabetes, body mass index, chronic kidney disease, prior coronary artery bypass graft, and J-CTO score.

CONCLUSIONS

Embracing a Fully TWA approach for CTO PCI might be associated with lower incidence of a composite endpoint of vascular complications and major bleeding, compared with a Conventional approach.