Treatment of the chronic total occlusion: A call to action for the interventional community

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.

Short- and Long-term Outcomes of Percutaneous Coronary Interventions in Chronic and Non-chronic Total Occlusions: A Meta-analysis of 690,123 Patients

The use of percutaneous coronary intervention (PCI) in patients with chronic total occlusion (CTO) is still a subject of debate, with conflicting outcomes reported in different studies when compared to non-CTO lesions. This meta-analysis aims to clarify the clinical outcomes of PCI in CTO cases compared to non-CTO lesions, both in the short and long-term. PubMed, Scopus, Web of Science, Ovid, and Cochrane Central were searched until March 2023 for relevant studies addressing short- and long-term outcomes of PCI in CTO vs non-CTO lesions. Dichotomous data were pooled as odds ratio (OR) with its 95% confidence interval (CI) in a random Der-Simonian lair effect model using STATA 17 MP. Eight studies with a total of 690,123 patients were included. In terms of short-term outcomes, CTO PCI was associated with higher rates of vessel perforation (OR = 2.16, 95% CI: 1.31-3.57) and cardiac tamponade (OR = 5.19, 95% CI: 4.29-6.28). Additionally, CTO PCI showed lower rates of procedural success (OR = 0.84, 95% CI: 0.73-0.96). Moreover, in the long-term, CTO PCI had higher rates of MACE (OR = 1.02, 95% CI: 1.01-1.04), however, it showed lower rates of cardiac death (OR = 0.61, 95% CI: 0.38-0.98), with no significant difference in other reported outcomes. Our findings underscore the challenges and adverse outcomes associated with using PCI to treat CTO lesions in the short term. This suggests that interventional cardiologists should carefully evaluate the risks and benefits before proceeding with PCI in CTO lesions.

Association of Successful Percutaneous Revascularization of Chronic Total Occlusions With Quality of Life: A Systematic Review and Meta-Analysis

Importance

Chronic total occlusion percutaneous coronary intervention (CTO-PCI) is not usually offered because of skepticism about long-term clinical benefits.

Objective

To assess the association of successful CTO-PCI with quality of life by analyzing the relevant domains of the Seattle Angina Questionnaire (SAQ).

Data Sources

PubMed, EMBASE, Web of Science, Google Scholar, and Cochrane databases were searched to identify randomized trials and observational studies specifically addressing quality of life domains of SAQ from January 2010 to June 2022.

Study Selection

Studies included reporting SAQ metrics such as angina frequency, physical limitation, and quality of life, before and after CTO-PCI.

Data Extraction and Synthesis

The present study was performed according to the Cochrane Collaboration and Preferred Reporting Items for Systematic Reviews and Meta-Analyses statements, in which fixed-effect or random-effect models with generic inverse-variance weighting depending on statistical homogeneity were applied. Data were extracted by 3 independent reviewers.

Outcomes and Measures

The primary outcome was angina frequency; physical limitation and quality of life were assessed as secondary outcomes.

Results

Seven prospective randomized or observational studies (2500 patients) were included, with a mean (SD) participant age of 61.2 (2.1) years. CTO-PCI was associated with significantly improved quality-of-life metrics during a mean (SD) follow-up of 14.8 (16.3) months. In patients with successful procedures, angina episodes became less frequent (mean [SD] difference for SAQ angina frequency of 12.9 [3.1] survey points [95% CI, 7.1-19.8 survey points]; standardized mean difference was 0.54 [95% CI, 0.21-0.92]; P = .002; I2 = 86.4%) and they experienced less physical activity limitation (mean [SD] difference for SAQ physical limitation of 9.7 [6.2] survey points [95% CI, 3.5-16.2 survey points]; standardized mean difference was 0.42 [95% CI, 0.24-0.55]; P < .001; I2 = 20.9%), and greater quality-of-life domain (mean [SD] difference for SAQ quality of life of 14.9 [3.5] survey points [95% CI, 7.7-22.5 survey points]; standardized mean difference was 0.41 [95% CI, 0.25-0.61]; P < .001; I2 = 58.8%) compared with patients with optimal medical therapy or failed procedure. Furthermore, follow-up duration (point estimate, 0.03; 95% CI, 0.01-0.04; P = .01) was associated with a significant decrease in angina frequency in meta-regression analysis.

Conclusions and Relevance

In this systematic review and meta-analysis examining quality of life following CTO-PCI, successful procedures were associated with improved quality-of-life parameters compared with patients on optimal medical therapy or after failed CTO-PCI. These findings suggest support for using PCI to treat CTOs in symptomatic patients unresponsive to medical treatment.

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.

Overview of Contemporary Chronic Total Occlusion Percutaneous Coronary Intervention Techniques: A Narrative Systematic Review

BACKGROUND

Despite the abundance of coronary chronic total occlusions (CTO) percutaneous coronary intervention (PCI) studies, the literature is not easy to digest for both general PCI operators and CTO PCI specialists because of the many varied terms used for approaches and inconsistency in terminology. This inconsistency makes it challenging to understand the advantages and disadvantages of these different approaches and, most importantly, their downstream clinical outcomes. Accordingly, we conducted a systematic review of all published studies on CTO PCI to describe techniques and algorithms used in the last decade to provide an overview on the efficacy and safety of contemporary CTO PCI techniques.

METHODS

We performed a comprehensive search of the PubMed, EMBASE, and the Cochrane library databases for manuscripts about PCI of CTOs. We included studies published between the years 2005 and 2019. We categorized studies into those using a single approach (antegrade, retrograde) and those with a prespecified algorithm (ie, hybrid approach).

RESULTS

Fifty-five observational studies including 28,907 patients who underwent CTO were included in this review. CTO PCI generally carries low risk of major procedural complications, with angiographic success rates being higher in studies that used an algorithmic vs single technical approach.

CONCLUSIONS

This systematic review highlights the wide variation in definitions and practices in CTO PCI and calls for standardization in terminology and practice.

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.

Indications and Patient Selection for Percutaneous Coronary Intervention of Chronic Total Occlusions

The most common indication for chronic total occlusion (CTO) percutaneous coronary intervention (PCI) is angina relief, which translates into improved physical function and quality of life. As the risk of the procedure is higher compared with non CTO PCI, it is important for operators to understand the current state of literature and have a detailed discussion with patients regarding risks and benefits prior to the procedure. This article discusses indications for the procedure and how to appropriately select patients for CTO PCI, in hopes of inspiring the reader to consistently offer this approach to indicated patients regardless of anatomic complexity.

Circulating CD34+VEGFR-2+ endothelial progenitor cells correlate with revascularization-mediated long-term improvement of cardiac function in patients with coronary chronic total occlusions

BACKGROUND

Endothelial progenitor cells (EPCs) participate in angiogenesis and neocollateralization. This study assessed if circulating EPCs can predict long-term improvement of global left ventricular systolic function in patients with coronary chronic total occlusions (CTOs) underwent successful percutaneous coronary intervention (PCI).

METHODS

In this single-center, prospective, observational study, 115 consecutive patients with CTOs were evaluated by standard transthoracic echocardiography (ECHO) before and 9-12 months after PCI. Numbers of circulating putative EPCs were determined by flow cytometry analysis of mononuclear cells isolated from peripheral blood samples drawn before and 72 h after PCI.

RESULTS

At mean 11.3 ± 2.5 months post vs. before PCI (all P < .05): by SAQ-7 summary scores, angina frequency, physical limitation and quality of life scores were greater; by ECHO, LVEDd decreased and LVEF increased, which were more significant in patients with Rentrop grades 2/3 vs. 0/1. At 72 h post vs. before PCI, CD34⁺VEGFR-2⁺CD133^- (0.82 ± 0.32 × 10⁶/L vs. 1.00 ± 0.39 × 10⁶/L, P = .003), CD34⁺VEGFR-2⁺CD133⁺ (0.24 ± 0.12 × 10⁶/L vs. 0.27 ± 0.14 × 10⁶/L, P = .028), and CD14⁺Tie2⁺VEGFR-2⁺ (6.60 ± 3.32 × 10⁶/L vs. 7.82 ± 3.91 × 10⁶/L, P = .006) cell numbers were lower. The baseline levels of CD34⁺VEGFR-2⁺cells (P = .001) and CD14⁺Tie2⁺VEGFR-2⁺cells (P < .001) were association with the grade of collateralization. In addition, the baseline and peri-procedural decrease of circulating CD34⁺VEGFR-2⁺ cells correlated with the increase of LVEF (P < .001, P < .001, respectively) and the decrease of LVEDd (P = .022, P = .029, respectively) at follow-up.

CONCLUSIONS

In this small study, the baseline levels of circulating CD34⁺VEGFR-2+ EPCs and its reduction after successful revascularization of CTOs correlated with long-term improvement in global LV systolic function.

Determinants of Greater Peak radiation skin dose in percutaneous coronary intervention for chronic total occlusion

BACKGROUND

Peak skin dose (PSD) is closely associated with skin radiation injuries such as skin ulcers in percutaneous coronary intervention (PCI). Although PSD is greater in PCI for chronic total occlusion (CTO) lesions as compared with non-CTO lesions, the determinants of PSD in CTO-PCI are not fully understood. The purpose of this study was to investigate the clinical factors associated with excess PSD in PCI for CTO.

METHODS

The study population included a total of 220 CTO-PCI cases that were divided into a standard PSD group (<2 Gy, n = 187) and an excess PSD group (≥2 Gy, n = 33). Clinical, lesion, and procedural characters were compared between the 2 groups. Multivariate logistic regression was performed to investigate the clinical factors associated with excess PSD.

RESULTS

Body surface area (BSA) was significantly higher in the excess PSD group (1.85 ± 0.24 m²) than the standard PSD group (1.71 ± 0.18 m²) (p = 0.001). The J-CTO score was significantly higher in the excess PSD group (2.51 ± 1.28) than the standard PSD group (1.60 ± 1.13) (p < 0.001). Multivariate logistic regression analysis revealed that BSA (0.1 mm increase: OR 1.663, 95% CI 1.300-2.128, p < 0.001) and J-CTO score (1-point increase: OR 2.015, 95% CI 1.322-3.071, p = 0.001) were significantly associated with excess PSD.

CONCLUSIONS

A large BSA and high J-CTO score were significantly associated with excess PSD. It is important to pay special attention to CTO patients who have a large BSA and/or high J-CTO score to reduce patient's PSD.

Evaluation of contrast nephropathy in percutaneous treatment of chronic total occlusions

Background

Contrast-induced nephropathy (CIN) is a leading cause of morbidity and mortality in patients undergoing percutaneous coronary intervention (PCI). Chronic total occlusions (CTO) are frequently observed among patients undergoing coronary angiography.

Methods

A total of 128 CTO patients were included. Mehran score, lesion characteristics, interventional procedure, serological specimens and devices were recorded. The first group was administered with 1 ml · kg^-1 · h^-1 saline (0.9% NaCl) infusion that started 12 h before the procedure and continued 12 h post procedure as recommended by the guidelines. The second group was administered with saline infusion of 12 ml · kg^-1 · h^-1 only during CTO-PCI procedure, which is called as intensive infusion.

Results

CIN development was similar in two groups (four patients in standard hydration group and five patients in intensive hydration group). The amount of saline was significantly higher in the standard group (1,767 ± 192.2 vs. 1,043.6 ± 375; p < 0.001). Patients with higher creatinine levels prior to PCI had a higher rate of CIN development after procedure. Interestingly, age, left ventricular ejection fraction, and diabetes mellitus independently predicted CIN.

Conclusion

Intensive hydration administration appears to be an effective and cost-effective method in CTO-PCI patients, especially in patients without left ventricular function failure.

Percutaneous Coronary Intervention With Drug-Eluting Stent Versus Optimal Medical Therapy for Chronic Total Occlusion: Systematic Review and Meta-Analysis

The optimal treatment strategy for coronary chronic total occlusion (CTO) has not been well established. The benefit of percutaneous coronary intervention (PCI) was inferred mainly from observational studies comparing successful versus failed PCI without a control group receiving optimal medical therapy (OMT). We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) and observational studies comparing PCI using drug-eluting stent (DES) versus OMT alone in patients with CTO. Eight studies were identified: 3 RCTs and 5 observational studies. Among a total of 4784 included patients, 2461 patients underwent PCI and 2323 patients received OMT. There was a significant association between PCI and lower cardiac mortality (odds ratio = 0.62; 95% confidence interval 0.42-0.93; P = .02). There was no significant difference between PCI and OMT regarding major adverse cardiac events, recurrent myocardial infarction (MI), repeat revascularization, or stroke. In the RCT subset (1399 patients), there was no significant difference between PCI and OMT regarding clinical outcomes. Compared with OMT alone, PCI with DES for CTO was associated with lower cardiac mortality, mainly driven by observational studies, without significant difference in recurrent MI or repeated revascularization. Further RCTs are needed to investigate the role of PCI for management of patients with CTO.

Full stent expansion of chronic total occlusion lesions requires prolonged inflation

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has been associated in some studies with higher target vessel revascularization (TVR) rates than non-CTO PCI. Optimal stent inflation time and its effect on TVR in CTO PCI is unknown. We investigated the time required for stent deployment using the previously described pressure optimized protocol (POP), which uses stent balloon pressure stability rather than an arbitrary inflation time as an end point for balloon deflation. We also compared TVR with CTO PCI vs non-CTO using the POP protocol in both groups.

METHODS

Patients with successful CTO PCI using POP between 2012 and 2015 were included. Patients having non-CTO PCI using POP and matched for stent diameter and length and temporal proximity constituted the control group to compare inflation time (n=83 each). TVR at 1year was compared between PCI during the time period using POP (CTO=83, non-CTO=263).

RESULTS

Stent inflation time to achieve optimal stent inflation using POP was longer in CTO vs non-CTO lesions (136±60 vs 108±51s, p=0.001). TVR at 365days was similar in CTO and non-CTO cohorts (2.4% vs 2.6%, p=0.9).

CONCLUSION

Stent expansion using POP in CTO lesions requires longer inflation duration but leads to similar TVR rates at 1year in CTO PCI compared with non-CTO PCI.

Angiographic predictors of success in antegrade approach of Chronic Total Occlusion interventions in a South Indian population in the contemporary era

Chronic Total Occlusion (CTO) intervention is a challenging area in interventional cardiology. Presently about 70% of CTO interventions are successful.

MATERIALS AND METHODS

This was a single center prospective study of a cohort of all patients undergoing percutaneous coronary intervention (PCI) as elective or adhoc procedure for CTO from August 2014 to June 2015. Only antegrade CTO interventions were included. In all patients the following data were recorded.

RESULTS

A total of 210 (8.9% of total PCI (2353) during the study period) CTO patients were followed up. The mean age was 56.54±8.9. In the study sixty nine patients (32.9%) presented with chronic stable angina and rest of the patients had history of acute coronary syndrome of which 22.9% (n=48) had unstable angina (UA) or non ST elevation myocardial infarction (NSTEMI) and 44.2% (n=93) had ST Elevation Myocardial Infarction (STEMI). In those with history of ACS, 64.78% (n=92) had ACS during the previous year and remaining 35.22% (n=49) had ACS prior to that. Single vessel CTO was seen in 89.5% (n=188) and two vessel CTO in 10.5% (n=22). LAD was involved in 36.7% (n=77), RCA in 48.1% (n=101), and LCX in 15.2% (n=32). Procedural success in the first attempt was 68.1% (n=143), which increased to 71.42% (n=150) after the second attempt. CTO interventions were more frequently successful when the calcium was absent or minimal (p-0.05), CTO length was <10mm (p<0.01) and good distal reformation (p<0.01).

Effects of Percutaneous Coronary Intervention on Viable Myocardium and Heart Function of Diabetic Patients With Chronic Total Occlusion

OBJECTIVE

The aim of this study was to compare the effects of percutaneous coronary intervention (PCI) on coronary chronic total occlusion patients with (DM) or without (NDM) diabetes mellitus.

METHODS

A total of 78 patients were divided into DM group and NDM group according to whether the patient has DM. The results of PCI were analyzed using quantitative coronary analysis. In addition, all the patients underwent Tc-MIBI (methoxyisobutylisonitrile) single-photon emission computed tomography (SPECT) and ultrasonic cardiogram in the first week and the sixth month after PCI to evaluate PCI results. During the 6-month follow-up, major adverse cardiac event (MACE) was recorded and analyzed as well.

RESULTS

The first and second classes of collateral circulation between the 2 groups have significant differences (P < 0.05). Left ventricular end-diastolic volume index and left ventricular end-systolic volume index were decreased at the sixth month compared with those at the first week. Left ventricular ejection fraction was significantly increased. In both groups, the defect size significantly reduced, and percentage of radionuclide scintigraphic count significantly increased between rest and nitroglycerin interventional SPECT. After 6 months, both groups repeated nitroglycerin interventional SPECT, which showed that defect size was significantly reduced, and the percentage of radionuclide scintigraphic count was significantly increased compared with those of the first week. During the 6-month follow-up, the incidence of MACE between the 2 groups had no significant difference.

CONCLUSIONS

Percutaneous coronary intervention has beneficial effects on heart functions and MACE when performed on chronic total occlusion patients with and without DM.

Approach to CTO Intervention: Overview of Techniques

OPINION STATEMENT

Successful percutaneous coronary intervention (PCI) of chronic total occlusions (CTOs) has been associated with significant clinical benefits, but remains technically demanding. Failure to cross the CTO with a guidewire is the most common cause of CTO PCI failure. CTO crossing can be achieved in the antegrade or retrograde direction and can be accomplished by maintaining true lumen position throughout or via subintimal dissection/reentry techniques. A procedural plan should be created prior to the procedure through careful angiographic review of four key parameters: (a) morphology of the proximal occlusion cap; (b) length of the occlusion; (c) quality of the distal vessel and presence of bifurcation at the distal cap; and (d) suitability of collateral circulation for retrograde crossing. Dual coronary injection is recommended in all cases with contralateral collaterals for detailed characterization of the lesion. If one approach fails to progress, a quick transition to the next approach is encouraged to maximize efficacy and efficiency. Procedural complications, including vessel perforation, may occur more frequently in CTO as compared with non-CTO PCI; hence, availability of necessary equipment and expertise in treating such complications are essential.

Association of β-blocker therapy with long-term clinical outcomes in patients with coronary chronic total occlusion

There are limited data regarding the efficacy of β-blockers for secondary prevention in patients with coronary chronic total occlusion (CTO). Therefore, we investigated the association of β-blocker therapy with long-term clinical outcomes in CTO patients. From March 2003 to February 2012, a total of 2024 CTO patients treated with either medical therapy alone or revascularization were enrolled in the study. We assessed 1596 patients with stable ischemic heart disease and divided them into the β-blocker group (n = 932) and the no-β-blocker group (n = 664). The primary outcome was all-cause death. The median follow-up duration was 3.9 (interquartile range: 2.0-6.2) years. All-cause death occurred in 11.6% patients in the β-blocker group and 13.6% patients in the no-β-blocker group (hazard ratio [HR]: 0.81, 95% confidence interval [CI]: 0.61-1.08; P = 0.15). In the propensity score-matched population (570 pairs), all-cause death occurred in 12.3% patients in the β-blocker group and 12.8% patients in the no-β-blocker group (HR: 0.93, 95% CI: 0.67-1.29; P = 0.66). In subgroup analysis, β-blocker therapy was associated with better outcome, in terms of all-cause death, in patients with CTO of the left anterior descending coronary artery and Synergy Between PCI with Taxus and Cardiac Surgery (SYNTAX) score ≥23 (P for interaction = 0.01 and 0.02, respectively). In conclusion, β-blocker therapy was not associated with favorable long-term clinical outcomes in stable CTO patients, regardless of treatment strategy. However, β-blocker therapy might be beneficial in a highly selective group of CTO patients with a high ischemic burden.

CT Angiography for Revascularization of CTO: Crossing the Borders of Diagnosis and Treatment

Coronary computed tomography angiography (CTA) is increasingly used to diagnose and rule out coronary artery disease. Beyond stenosis detection, the ability of CTA to visualize and characterize coronary atherosclerotic plaque, as well as to obtain 3-dimensional coronary vessel trajectories, has generated considerable interest in the context of pre-procedural planning for revascularization of chronic total occlusions (CTOs). Coronary CTA can characterize features that influence the success rate of percutaneous coronary intervention (PCI) for CTOs such as the extent of calcification, vessel tortuosity, stump morphology, presence of multiple occlusions, and lesion length. Single features and combined scoring systems based on CTA may be used to grade the level of difficulty of the CTOs before PCI and have been shown to predict procedural success rates in several trials. In addition, the procedure itself may be facilitated by real-time integration of 3-dimensional CTA data and fluoroscopic images in the catheterization laboratory. Finally, the ability of coronary CTA to assess anatomy, perfusion, and viability in 1 single examination makes it a potential "one stop shop" that predicts not only the likelihood of successful PCI but also the clinical benefit of CTO revascularization. Further research is clearly needed, but many experienced sites have already integrated coronary CTA into the routine planning and guiding of CTO procedures.

Percutaneous Coronary Revascularization for Chronic Total Occlusions: A Novel Predictive Score of Technical Failure Using Advanced Technologies

OBJECTIVES

The aims of this study were to describe the 10-year experience of a single operator dedicated to chronic total occlusion (CTO) and to establish a model for predicting technical failure.

BACKGROUND

During the last decade, the interest in percutaneous coronary interventions (PCIs) of chronic total occlusions (CTOs) has increased, allowing the improvement of success rate.

METHODS

One thousand nineteen patients with CTO underwent 1,073 CTO procedures performed by a single CTO-dedicated operator. The study population was subdivided into 2 groups by time period: period 1 (January 2005 to December 2009, n = 378) and period 2 (January 2010 to December 2014, n = 641). Observations were randomly assigned to a derivation set and a validation set (in a 2:1 ratio). A prediction score was established by assigning points for each independent predictor of technical failure in the derivation set according to the beta coefficient and summing all points accrued.

RESULTS

Lesions attempted in period 2 were more complex in comparison with those in period 1. Compared with period 1, both technical and clinical success rates significantly improved (from 87.8% to 94.4% [p = 0.001] and from 77.6% to 89.9% [p < 0.001], respectively). A prediction score for technical failure including age ≥75 years (1 point), ostial location (1 point), and collateral filling Rentrop grade <2 (2 points) was established, stratifying procedures into 4 difficulty groups: easy (0), intermediate (1), difficult (2), and very difficult (3 or 4), with decreasing technical success rates. In derivation and validation sets, areas under the curve were comparable (0.728 and 0.772, respectively).

CONCLUSIONS

With growing expertise, the success rate has increased despite increasing complexity of attempted lesions. The established model predicted the probability of technical failure and thus might be applied to grading the difficulty of CTO procedures.

Impact of Crossing Strategy on Intermediate-term Outcomes After Chronic Total Occlusion Percutaneous Coronary Intervention

BACKGROUND

There is ongoing controversy about the optimal crossing strategy selection for chronic total occlusion (CTO) percutaneous coronary intervention (PCI), especially regarding the relative merits of antegrade dissection/re-entry and the retrograde approach.

METHODS

We retrospectively examined the clinical outcomes of 173 consecutive patients who underwent successful CTO PCI at our institution between January 2012 and March 2015.

RESULTS

The mean age was 65 ± 8 years, and 98% of the patients were men with a high prevalence of diabetes (60%), previous coronary artery bypass grafting (CABG) (31%), and previous PCI (54%). The successful CTO crossing strategy was antegrade wire escalation in 79 patients (45.5%), antegrade dissection/re-entry in 58 patients (33.5%), retrograde wire escalation in 11 patients (6.4%), and retrograde dissection and re-entry in 25 patients (14.5%). The retrograde approach was more commonly used in lesions with interventional collaterals (P < 0.0001), moderate/severe calcification (P = 0.02), blunt stump (P = 0.01), and a higher Japan Chronic Total Occlusion score (P = 0.0002). Use of dissection and re-entry (both antegrade and retrograde) was associated with bifurcation and the distal cap (P = 0.004), longer CTO occlusion length (P < 0.0001), and longer stent length (P < 0.0001). Median follow-up was 11 months. The 12-month incidence of death, myocardial infarction, and the composite of acute coronary syndrome/target lesion revascularization/target vessel revascularization was 2.5%, 4.9%, and 24.4%, respectively, and was similar with intimal and subintimal crossing strategies.

CONCLUSIONS

Antegrade dissection/re-entry and retrograde approaches are frequently used during CTO PCI and were associated with similarly favorable intermediate-term outcomes as antegrade wire escalation.

Application and outcomes of a hybrid approach to chronic total occlusion percutaneous coronary intervention in a contemporary multicenter US registry

BACKGROUND

A hybrid approach to chronic total occlusion (CTO) percutaneous coronary intervention (PCI) prioritizing and combining all available crossing techniques was developed to optimize procedural efficacy, efficiency, and safety, but there is limited published data on its outcomes.

METHODS

We examined the procedural techniques and outcomes of 1036 consecutive CTO PCIs performed using a hybrid approach between 2012 and 2015 at 11 US centers.

RESULTS

Mean age was 65 ± 10 years and 86% of the patients were men, with a high prevalence of diabetes mellitus (43%) and prior coronary artery bypass graft surgery (34%). Most target CTOs were located in the right coronary artery (59%), followed by the left anterior descending artery (23%) and the circumflex (19%). Dual injection was used in 71%. Technical success was achieved in 91% and a major procedural complication occurred in 1.7% of cases. The final successful crossing technique was antegrade wire escalation in 46%, antegrade dissection/re-entry in 26%, and retrograde in 28%. The initial crossing strategy was successful in 58% of the lesions, whereas 39% required an additional approach. Overall, antegrade wire escalation was used in 71%, antegrade dissection/re-entry in 36%, and the retrograde approach in 42% of procedures. Median contrast volume, fluoroscopy time, and air kerma radiation dose were 260 (200-360) ml, 44 (27-72) min, and 3.4 (2.0-5.4) Gray, respectively.

CONCLUSION

Application of a hybrid approach to CTO crossing resulted in high success and low complication rates across a varied group of operators and hospital practice structures, supporting its expanding use in CTO PCI.

Answer the call: let's make 2015 the year of magical thinking in CTO PCI

Prevalence of chronic total occlusions (CTO's) is as high as 50% in angiographic series Patients are helped with successful recanalization of CTO's In spite of current improved success rates in CTO percutaneous coronary intervention (PCI), only 10-12% of CTO's are currently attempted.