A Percutaneous Treatment Algorithm for Crossing Coronary Chronic Total Occlusions

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

OBJECTIVES

We aimed to evaluate the efficacy and safety of antegrade fenestration and reentry (AFR) for chronic total occlusion (CTO) recanalization in a multicenter registry.

BACKGROUND

Adoption of antegrade dissection/reentry (ADR) for CTO recanalization has been limited, and novel ADR techniques are needed.

METHODS

AFR involves the balloon-induced creation of multiple fenestrations between the false and true lumen. A targeted true lumen reentry is subsequently achieved with a low tip-load polymer-jacketed guidewire. Following the initial description and dissemination of AFR, patients undergoing AFR-based CTO recanalization at nine centers were included in the present registry. Study endpoints were AFR success, procedural success, and target-lesion failure (TLF) on follow-up.

RESULTS

We included 41 patients. Mean J-CTO score was 2.5 ± 1.4. In 80.5% of cases, AFR was performed after failed antegrade wire escalation. Another ADR technique was used before AFR in one-third of cases. AFR achieved distal true lumen reentry in n = 27/41 (65.9%) cases. In n = 14/41 (34.1%) cases with AFR failure, use of alternative techniques led to successful CTO recanalization in eight additional patients. The overall technical and procedural success rates were 85.4% and 82.9%, respectively. No AFR-related complications were observed. One-year TLF rate was 8.3% overall, with no differences between successful and failed AFR.

CONCLUSIONS

We report on AFR feasibility in a multicenter registry of patients undergoing CTO recanalization. We observed a moderate success rate, coupled with the absence of complications. Moreover, even a failed AFR attempt did not preclude the use of alternative techniques to achieve recanalization. Further studies should confirm and extend our findings.

Outcomes of Chronic Total Occlusion Percutaneous Coronary Intervention in Patients With Renal Dysfunction

Although contemporary chronic total occlusion (CTO) percutaneous coronary intervention (PCI) is performed with high success rates, 10% to 13% of patients presenting with CTOs have chronic kidney disease (CKD), and the comparative safety, efficacy, and health status benefit of CTO PCI in these patients, has not been well defined. We examined the association of baseline renal function with periprocedural major adverse cardiovascular and cerebral events and health status outcomes in 957 consecutive patients (mean age 65.3 ± 10.3 years, 19.4% women, 90.3% white, 23.6 CKD [estimated glomerular filtration rate {eGFR} < 60]) in the OPEN-CTO (Outcomes, Patients Health Status, and Efficiency in Chronic Total Occlusions Registry) study. Hierarchical multivariable regression models were used to examine the independent association of baseline eGFR with technical success, periprocedural complications and change in health status, using Seattle Angina Questionnaire (SAQ) over 1 year. Crude rates of acute kidney injury were higher (13.5% vs 4.4%, p <0.001) and technical success lower (81.8% vs 88.4%, p = 0.01) in patients with CKD. There were no significant differences in other periprocedural complications. After adjustment for confounding factors, there was no significant association of baseline eGFR with technical success or periprocedural major adverse cardiovascular and cerebral events (death, myocardial infarction, emergent bypass surgery, stroke, perforation), whereas patients with lower eGFR had higher rates of acute kidney injury. The difference in SAQ summary score, between patients on the 10th and 90th percentile for baseline eGFR distribution was not clinically significant (1 month: -0.91; 1 year: -3.06 points). In conclusion, CTO PCI success, complication rates, and the health status improvement after CTO PCI are similar in patients across a range of baseline eGFRs.

Percutaneous coronary intervention in aorto-ostial coronary chronic total occlusion: outcomes and technical considerations in a multicenter registry

INTRODUCTION AND OBJECTIVES

Percutaneous coronary intervention (PCI) for aorto-ostial chronic total coronary occlusion (CTO) can be a particularly challenging lesion subset. The aim of this study was to analyze the technical aspects and outcomes of aorto-ostial CTO PCI in a multicenter registry.

METHODS

Patients undergoing aorto-ostial CTO PCI at 4 centers between February 2013 and December 2018 were included. Success rates, as well as procedural aspects and outcomes, were analyzed.

RESULTS

A total of 103 patients were included. Mean age was 64±10 years and the mean J-CTO score was 3.1±1.1. Thirty-one lesions (30.4%) were flush ostial CTOs. Technical and procedural success were achieved in 79 (76.7%) and 78 (75.7%) of the patients, respectively. The retrograde approach was the most frequent successful crossing technique (n=49; 62.0%), especially in flush vs nonflush aorto-ostial CTOs (82.6% vs 53.5%; P=.02). The only variable independently associated with technical failure was the absence of interventional collaterals (OR, 12.38; 95%CI, 4.02-38.15; P <.001). Coronary perforation occurred in 4 patients (3.9%) requiring covered stent implantation (without subsequent cardiac tamponade) and 2 patients (1.9%) had a stroke (one of which was a transient ischemic attack). During a median follow-up of 31 months, 3 (2.9%) patients died from cardiovascular causes and 13 (12.6%) required repeat target vessel revascularization.

CONCLUSIONS

Aorto-ostial occlusions represent a challenging subset for PCI. However, an acceptable success rate with favorable outcomes during follow-up can be achieved by experienced operators. The presence of interventional collaterals allowing the use of the retrograde approach is key for achieving procedural success.

The impact of dissection and re-entry versus wire escalation techniques on long-term clinical outcomes in patients with chronic total occlusion lesions following percutaneous coronary intervention: An updated meta-analysis

BACKGROUND

The meta-analysis was performed to evaluate the effect of dissection and re-entry (DR) vs. wire escalation (WE) techniques on long-term clinical outcomes in patients with chronic total occlusion (CTO) lesions undergoing percutaneous coronary intervention.

METHODS

Studies were searched in electronic databases from inception to September, 2019. Results were pooled using random effects model and fixed effects model and are presented as risk ratios (RR) with 95% confidence intervals (CI).

RESULTS

Pooled analyses revealed that patients with DR techniques had overall higher complexity CTO lesions than patients with WE techniques and required a greater number of stents and a greater mean stent length. The "extensive" DR techniques may have a higher incidence of target vessel revascularization (TVR) (RR = 2.30, 95% CI: 1.77-2.98), in-stent restenosis (RR = 1.71, 95% CI: 1.30-2.23), in-stent reocclusion (RR = 1.86, 95% CI: 1.03-3.3) and death/myocardial infarction/TVR (RR = 2.10, 95% CI: 1.71-2.58), when compared with WE techniques, during the long-term follow-up. However, "limited" DR techniques result in more promising outcomes, and are comparable to conventional WE techniques.

CONCLUSIONS

Dissection and re-entry techniques were associated with increased risk of long-term negative clinical events, especially "extensive" DR techniques. However, "limited" DR techniques resulted in good long-term outcomes, comparable to WE techniques.

Appropriate Use Criteria and Health Status Outcomes Following Chronic Total Occlusion Percutaneous Coronary Intervention: Insights From the OPEN-CTO Registry

BACKGROUND

The American College of Cardiology/American Heart Association Appropriate Use Criteria were designed to aid clinical decision-making, yet their association with health status outcomes after chronic total occlusion percutaneous coronary intervention (PCI) is unknown.

METHODS

We analyzed 769 patients with baseline and 1-year health status data after chronic total occlusion PCI. Procedures were categorized as appropriate, may be appropriate, or rarely appropriate. Mean changes in patient-reported health status, assessed by the Seattle Angina Questionnaire (SAQ), were compared across appropriate use criteria categories from baseline to 1 year. Change in SAQ summary score was stratified as little to no benefit (≤10 points), intermediate (10-19 points), large (20-29 points), and very large (≥30 points).

RESULTS

The appropriate use criteria indication was appropriate in 573 patients (74.5%), may be appropriate in 191 (24.8%), and rarely appropriate in 5 (0.7%). Patients in the appropriate group reported greater improvement in SAQ summary scores (27.3±21.3 points) at 1 year compared with the may be appropriate (22.5±20.9; P=0.01). A similar pattern was noted for SAQ angina frequency (mean change 24.0±27.2 versus 18.7±25.6; P=0.02). The appropriate group had the highest proportion of very large improvements in SAQ summary scores (44.5% versus 33.3%; P=0.01).

CONCLUSIONS

Among patients undergoing chronic total occlusion PCI, the rate of rarely appropriate PCI was low. The rate of appropriate PCI was high and was associated with the greatest health status improvement at 1 year. A substantial proportion of patients in the may be appropriate group experienced meaningful health status benefits as well.

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.

Transcoronary Rapid Pacing Solving a Complex Retrograde Chronic Total Occlusion Procedure

We report a case of revascularization of the right coronary artery via the epicardial collateral, for which we used transcoronary rapid pacing to obtain cardiac standstill while puncturing the distal chronic total occlusion (CTO) cap. To our knowledge, this is the first case in which this technique has been used in CTO. (Level of Difficulty: Advanced.)

Outcomes with retrograde versus antegrade chronic total occlusion revascularization

OBJECTIVES

The aim of the study was to evaluate the outcomes of retrograde versus antegrade approach in chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

BACKGROUND

The retrograde approach has increased the success rate of CTO PCI but has been associated with a higher risk for complications.

METHODS

We conducted a meta-analysis of studies published between 2000 and August 2019 comparing the in-hospital and long-term outcomes with retrograde versus antegrade CTO PCI.

RESULTS

Twelve observational studies (10,240 patients) met our inclusion criteria (retrograde approach 2,789 patients, antegrade approach 7,451 patients). Lesions treated with the retrograde approach had higher J-CTO score (2.8 vs. 1.9, p < .001). Retrograde CTO PCI was associated with a lower success rate (80.9% vs. 87.4%, p < .001). Both approaches had similar in-hospital mortality, urgent revascularization, and cerebrovascular events. Retrograde CTO PCI was associated with higher risk of in-hospital myocardial infarction (MI; odds ratio [OR] 2.37, 95% confidence intervals [CI] 1.7, 3.32, p < .001), urgent pericardiocentesis (OR 2.53, 95% CI 1.41-4.51, p = .002), and contrast-induced nephropathy (OR 2.12, 95% CI 1.47-3.08; p < .001). During a mean follow-up of 48 ± 31 months retrograde crossing had similar mortality (OR 1.79, 95% CI 0.84-3.81, p = .13), but a higher incidence of MI (OR 2.07, 95% CI 1.1-3.88, p = .02), target vessel revascularization (OR 1.92, 95% CI 1.49-2.46, p < .001), and target lesion revascularization (OR 2.08, 95% CI 1.33-3.28, p = .001).

CONCLUSIONS

Compared with antegrade CTO PCI, retrograde CTO PCI is performed in more complex lesions and is associated with a higher risk for acute and long-term adverse events.

Advances in CrossBoss/Stingray use in antegrade dissection reentry from the Asia Pacific Chronic Total Occlusion Club

Antegrade dissection reentry with Stingray device (Boston Scientific, Marlborough, MA) accounts for 20–34% of the chronic total occlusion (CTO) cases in the various hybrid operators' CTO registries and is an important component of CTO crossing algorithms. The Stingray device can facilitate antegrade dissection and reentry, however its use is low outside North America and Europe. The Asia Pacific CTO Club along with three experience Stingray operators from the US, Europe and India, created an algorithm guiding use of the CrossBoss and Stingray catheter. This APCTO Stingray algorithm defines when to use the CrossBoss and Stingray device recommending a reduction in CrossBoss use except for in‐stent restenosis lesions and immediate transition from knuckle wiring to the Stingray device. When antegrade wiring fails, choice of Stingray‐facilitated reentry versus parallel wiring depends on operator experience, device availability, cost concerns, and anatomical factors. When the antegrade wire enters the subintimal space, we recommend using a rotational microcatheter to produce a channel and deliver the Stingray balloon—so called the “bougie technique.” We recommend early switch to Stingray rather than persisting with single wire redirection or parallel wire. We recommend choosing a suitable reentry zone based on preprocedural computer tomography or angiogram, routine use of stick and swap, routine use of Subintimal TRAnscatheter Withdrawal (STRAW) through the Stingray balloon, and the multi stick and swap technique. We believe these techniques and algorithm can facilitate incorporation of the Stingray balloon into the practice of CTO interventionists globally.

Impact of Specific Crossing Techniques in Chronic Total Occlusion Percutaneous Coronary Intervention on Recovery of Absolute Myocardial Perfusion

Background:

Multiple crossing techniques in chronic total occlusion (CTO) percutaneous coronary intervention have been developed. This study compared recovery of quantitative myocardial blood flow (MBF) after different CTO percutaneous coronary intervention techniques.

Methods:

Consecutive patients with [ 15 O]H 2 O positron emission tomography perfusion imaging before and 3 months after successful CTO percutaneous coronary intervention between 2013 and 2018 were included. Changes in hyperemic MBF, coronary flow reserve, and perfusion defect size were compared between antegrade wire escalation, retrograde wire escalation, antegrade dissection and reentry (ADR), and retrograde dissection and reentry.

Results:

One hundred ninety-three patients were treated with antegrade wire escalation (N=90), retrograde wire escalation (N=24), ADR (N=35), and retrograde dissection and reentry (N=44). Increase in hyperemic MBF (1.19±0.77, 0.94±0.65, 1.09±0.63, and 1.02±0.75 mL·min -1 ·g -1 , respectively; P =0.40) and coronary flow reserve (1.34±1.08, 1.14±1.09, 1.31±0.96, and 1.24±0.99, respectively; P =0.84) and decrease in defect size (3.2±2.1, 3.0±2.2, 2.7±2.1, and 2.9±1.9 segments, respectively; P =0.77) were comparable between the 4 approaches. In addition, recovery of hyperemic MBF was less pronounced after subintimal crossing with knuckle-wire-technique compared with CrossBoss in controlled ADR and retrograde dissection and reentry (0.93±0.69 versus 1.54±0.65 mL·min -1 ·g -1 , P =0.02), and less after reentry using subintimal tracking and reentry in ADR compared with controlled ADR (Stingray) or limited antegrade subintimal tracking (0.60±0.53 versus 1.18±0.54 [ P =0.04] and versus 1.49±0.57 mL·min -1 ·g -1 , [ P <0.01]).

Conclusions:

Recovery of hyperemic MBF, coronary flow reserve, and perfusion defect size after CTO percutaneous coronary intervention was comparable between different approaches. Although sometimes necessary to cross a complex CTO lesion, subintimal knuckle wiring and subintimal tracking and reentry resulted in less hyperemic MBF improvement compared with other subintimal crossing and reentry techniques.

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.

Current approaches for treatment of coronary chronic occlusions

Introduction: Coronary chronic total occlusions (CTO) represent a challenging subset in interventional cardiology.Areas covered: During the last decade, improvements in materials, techniques, and meticulous pre-procedural lesion assessment have increased the success rate in CTO lesions. Several scores have been developed to address overall lesion evaluation and help select the most appropriate treatment strategy. In addition, specific algorithms such as the hybrid algorithm have been introduced to provide a framework for CTO operators and a rapid management of the various challenging aspects of the procedure. The hybrid approach requires operator's ability to switch from one treatment strategy to another when the first one appears to be unsuccessful. Adequate training and operators' experience remain crucial to improve the likelihood of success.Expert opinion: The aim of this review is to provide insights and guidance for operators on current approaches for treatment of CTO and complication management.

Modified subintimal transcatheter withdrawal: A novel technique for hematoma decompression to facilitate distal reentry during coronary chronic total occlusion recanalization

A controlled antegrade dissection and reentry technique is the most commonly employed crossing strategy for long coronary chronic total occlusions. The development of compressive hematoma is a recognized complication and results in the impairment of distal vessel visualization and hinders successful reentry attempts. We describe a novel technique utilizing a widely available microcatheter to decompress the subintimal hematoma to restore distal visualization and allow successful reentry.

Assessment of reattempted percutaneous coronary intervention strategy for chronic total occlusion after prior failed procedures: Analysis of the Japanese CTO-PCI Expert Registry

OBJECTIVES

We aimed to investigate strategies for reattempted percutaneous coronary interventions (PCIs) for chronic total occlusions (CTOs) by highly skilled operators after a failed attempt.

BACKGROUND

Development of complex techniques and algorithms has been standardized for CTO-PCI. However, there is no appropriate strategy for CTO-PCI after a failed procedure.

METHOD

From 2014 to 2016, the Japanese CTO-PCI Expert Registry included 4,053 consecutive CTO-PCIs (mean age: 66.8 ± 10.9 years; male: 85.6%; Japanese CTO [J-CTO] score: 1.92 ± 1.15). Initial outcomes and strategies for reattempted CTO-PCIs were evaluated and compared with first-attempt CTO-PCIs.

RESULTS

Reattempt CTO-PCIs were performed in 820 (20.2%) lesions. The mean J-CTO score of reattempt CTO-PCIs was higher than that of first-attempt CTO-PCIs (2.86 ± 1.03 vs. 1.68 ± 1.05, p < .001). The technical success rate of reattempt CTO-PCIs was lower than that of first-attempt CTO-PCIs (86.7% vs. 90.8%, p < .001). Regarding successful CTO-PCIs, the strategies comprised antegrade alone (reattempt: 36.1%, first attempt: 63.8%), bidirectional approach (reattempt: 54.4%, first attempt: 30.3%), and antegrade approach following a failed bidirectional approach (reattempt: 9.4%, first attempt: 5.4%). Parallel wire technique, intravascular ultrasound guide crossing, and bidirectional approach technique were frequently performed in reattempt CTO-PCIs. Reattempt CTO-PCIs showed higher rates of myocardial infarction (2.1% vs. 0.9%, p < .001) and coronary perforation (6.9% vs. 4.2%, p = .002) than first-attempt CTO-PCIs.

CONCLUSIONS

The technical success rate of reattempt CTO-PCIs is lower than that of first-attempt CTO-PCIs. However, using more complex strategies, the success rate of reattempt CTO-PCI can be improved by highly skilled operators.

Subintimal Versus Intraplaque Recanalization of Coronary Chronic Total Occlusions: Mid-Term Angiographic and OCT Findings From the ISAR-OCT-CTO Registry

OBJECTIVES

The aim of this study was to compare angiographic and optical coherence tomography findings following subintimal as opposed to intraplaque recanalization of chronic total occlusions (CTOs).

BACKGROUND

There is ongoing controversy regarding outcomes of intraplaque versus subintimal CTO recanalization.

METHODS

Consecutive patients undergoing angiography and intravascular optical coherence tomography following CTO recanalization were included in the ISAR-OCT-CTO (Intracoronary Stenting and Angiographic Results - Optical Coherence Tomography for Chronic Total Occlusions) registry. The study endpoints were percent diameter stenosis and late lumen loss as well as rate of uncovered and malapposed struts. Independent correlates of uncovered and malapposed struts were assessed by multivariate analysis.

RESULTS

The study included 75 patients. Intraplaque and dissection and re-entry techniques (DART) were used in 46 and 29 patients, respectively. There were no differences in terms of in-segment percent diameter stenosis (median 36.9 [interquartile range (IQR): 26.4 to 43.1] vs. 31.2 [IQR: 23.2 to 49.5]; p = 0.656), in-stent late lumen loss (0.215 mm [IQR: 0.063 to 0.495 mm] vs. 0.230 mm [IQR: 0.060 to 0.645 mm]; p = 0.837), or in-segment late lumen loss (0.030 mm [IQR: -0.278 to 0.510 mm] vs. 0.130 mm [IQR: -0.120 to 0.500 mm]; p = 0.395) at follow-up between the 2 techniques. Optical coherence tomography analysis showed comparable strut coverage (79.9% vs. 71.3%; p = 0.255) but significantly higher strut malapposition (6.6% vs. 13.6%; p < 0.001) following DART. Use of DART independently correlated with presence of strut malapposition (odds ratio: 3.41; 95% confidence interval: 1.24 to 9.36; p = 0.017) but not of strut coverage (odds ratio: 0.65; 95% confidence interval: 0.28 to 1.49; p = 0.314).

CONCLUSIONS

Intraplaque and subintimal recanalization techniques are associated with comparable mid-term angiographic results. Although the rate of uncovered struts is high following CTO recanalization, the recanalization technique does not independently correlate with presence of uncovered struts. There is a high rate of strut malapposition following CTO recanalization, particularly if achieved by means of DART.

Initial report of safety and procedure duration of robotic-assisted chronic total occlusion coronary intervention

BACKGROUND

No previous reports have examined the impact of robotic-assisted (RA) chronic total occlusion (CTO) PCI on procedural duration or safety compared to totally manual CTO PCI.

METHODS

Among 95 patients who underwent successful PCI of a single CTO lesion at two centers, 49 (52%) were performed RA and were performed 46 (48%) totally manually. Cockpit time was the time the primary operator entered to robotic cockpit until the procedure was complete. "Theoretical" cockpit time in the control group was time the primary operator would have entered the cockpit after lesion crossing until the procedure was complete. Major adverse events (MAEs) were the composite of death, myocardial infarction, clinical perforation, significant vessel dissection, arrhythmia, acute thrombosis, and stroke.

RESULTS

The lesion characteristics, procedural time, and contrast dose were similar. All procedures except for one (2%) selected for robotic completion after lesion crossing were completed successfully. The frequency of MAE was similar between groups and there were no in-hospital deaths. The cockpit time was 8 min longer in RA CTO PCI than the theoretical cockpit time in totally manual CTO PCI (40.6 ± 12.7 vs. 32.1 ± 17.8, p < .01).

CONCLUSION

RA CTO PCI was not associated with excess adverse events compared with totally manual CTO PCI and resulted in an average 41 min cockpit time equaling to 48% of procedure time without radiation exposure or requirement for the primary operator to wear a lead apron. Understanding the relationship between cockpit time and reductions in radiation exposure and lead apron-related orthopedic complications for operators requires future study.

Examining the Operator Learning Curve for Percutaneous Coronary Intervention of Chronic Total Occlusions

Background:

Advances in chronic total occlusion percutaneous coronary intervention (CTO PCI) techniques have led to increased procedural success rates among operators. While utilization of CTO PCI has disseminated widely, the learning curve for new operators has not been well-defined.

Methods:

Between July 2009 and December 2015, 93 875 CTO PCI cases were extracted from the CathPCI Registry. We delineated a cohort of new CTO operators performing <10 CTO PCI cases per given year. In-hospital outcomes for subsequent CTO PCIs were stratified by the number of prior cases accrued by each operator. Multivariable regression models were used to estimate differences in outcomes with increasing experience. The primary outcome was major adverse cardiovascular events defined as the composite of death, myocardial infarction, stroke, tamponade, or urgent coronary artery bypass grafting.

Results:

Among 70 916 cases performed by 7251 new operators, procedure success rate was 61.4% and major adverse cardiovascular event rate was 4.2%. Meanwhile, the rate of major bleeding was 4.0%, myocardial infarction 2.0%, mortality 0.6%, tamponade 0.3%, and renal failure 0.2%. Adjusted regression models demonstrated piecewise linear improvements in guidewire crossing, stent placement, and procedure success with accrued volume, albeit with increased contrast use, fluoroscopy time, and bleeding. Major adverse cardiovascular event rates were stable beyond the 12th case (odds ratio per 5 case increase 1.00; 95% CI, 0.98–1.03, P =0.7980).

Conclusions:

Among a large number of new CTO PCI operators in the United States, there exists an experiential learning curve for procedural success. However, there were higher rates of bleeding despite case experience, while major adverse cardiovascular events remained relatively unchanged after initiation.

Collateral Channel Size and Tortuosity Predict Retrograde Percutaneous Coronary Intervention Success for Chronic Total Occlusion

BACKGROUND

There is little evidence on how to select an interventional collateral channel (CC) in retrograde chronic total occlusion (CTO) percutaneous coronary intervention. We aimed to identify independent angiographic predictors of CC tracking and technical success in retrograde CTO percutaneous coronary intervention.

METHODS AND RESULTS

From January 2012 to December 2015, a total of 216 consecutive retrograde CTO percutaneous coronary intervention attempts by a high-volume operator in a tertiary university-affiliated hospital were enrolled. The clinical, angiographic, and procedural details were collected. The characteristics analyzed included channel type, size, tortuosity, angle of attack, length to emerging point, and the Multicenter CTO Registry of Japan score. The Multicenter CTO Registry of Japan score was 4.2±0.8. A total of 242 CCs were attempted for intervention. CC tracking success rate was 83.5%, and the technical success rate (per CC) was 81.4%. The per-patient technical success rate was 91.2%, and the major procedural complication rate was 4.6%. The atrioventricular groove, epicardial, and septal CCs were used in 36 (14.9%), 84 (34.7%), and 122 (50.4%) tracking attempts, respectively. In multivariable analysis, only large channel size and lack of tortuosity were significant independent predictors of CC tracking and technical success. A new scoring system was developed, while large size was given 1 point and lack of tortuosity was given 2 points. The receiver-operating characteristic area by the new model to predict CC tracking and technical success were 0.800 and 0.752, respectively.

CONCLUSIONS

In retrograde CTO percutaneous coronary intervention, only size and tortuosity of a CC are independent angiographic predictors of CC tracking and technical success.

Guiding Principles for Chronic Total Occlusion Percutaneous Coronary Intervention

Outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) have improved because of advancements in equipment and techniques. With global collaboration and knowledge sharing, we have identified 7 common principles that are widely accepted as best practices for CTO-PCI.  1. Ischemic symptom improvement is the primary indication for CTO-PCI.  2. Dual coronary angiography and in-depth and structured review of the angiogram (and, if available, coronary computed tomography angiography) are key for planning and safely performing CTO-PCI.  3. Use of a microcatheter is essential for optimal guidewire manipulation and exchanges.  4. Antegrade wiring, antegrade dissection and reentry, and the retrograde approach are all complementary and necessary crossing strategies. Antegrade wiring is the most common initial technique, whereas retrograde and antegrade dissection and reentry are often required for more complex CTOs.  5. If the initially selected crossing strategy fails, efficient change to an alternative crossing technique increases the likelihood of eventual PCI success, shortens procedure time, and lowers radiation and contrast use.  6. Specific CTO-PCI expertise and volume and the availability of specialized equipment will increase the likelihood of crossing success and facilitate prevention and management of complications, such as perforation.  7. Meticulous attention to lesion preparation and stenting technique, often requiring intracoronary imaging, is required to ensure optimum stent expansion and minimize the risk of short- and long-term adverse events. These principles have been widely adopted by experienced CTO-PCI operators and centers currently achieving high success and acceptable complication rates. Outcomes are less optimal at less experienced centers, highlighting the need for broader adoption of the aforementioned 7 guiding principles along with the development of additional simple and safe CTO crossing and revascularization strategies through ongoing research, education, and training.

Chronic Total Occlusion Wiring: A State-of-the-Art Guide From The Asia Pacific Chronic Total Occlusion Club

OBJECTIVE

Despite the advances in wire technology and development of algorithm-driven methodology for chronic total occlusion (CTO) intervention, there is a void in the literature about the technical aspects of CTO wiring. The Asia Pacific CTO Club, a group of 10 experienced operators in the Asia Pacific region, has tried to fill this void with this state-of-the-art review on CTO wiring.

METHODS

This review explains, for proximal cap puncture: choices of wires, shaping of the wire, use of dual lumen catheter, and method of step-down of wire penetration force for successful wiring. In wiring the CTO body, the techniques of loose tissue tracking, intentional intimal plaque tracking, and intentional subintimal wiring are described in detail. For distal lumen wiring, a blunt distal cap, presence of a distal cap side branch, calcium, and sharp tapered distal stump predict cap toughness, and wire penetration force should be stepped-up in these cases. The importance of choosing between redirection, parallel wiring, and Stingray (Boston Scientific, Marlborough, MA, USA) for angiographic guidance is discussed along with which will be more successful. On the retrograde side, the problems encountered with distal cap puncture and methods to overcome these problems are explained. The method of wiring the CTO body through a retrograde approach depending on the morphology of the CTO is described. Different reverse controlled antegrade and retrograde tracking (CART) wiring methods - including end balloon wiring, side balloon entry, and conventional reverse CART - are explained in detail.

CONCLUSION

This is a systematic CTO wiring review, which is believed to be beneficial for CTO operators worldwide.

Effects of Curcuminoids on Myocardial Injury After Percutaneous Coronary Intervention

The rise of cardiac troponin post-percutaneous coronary intervention (PCI) is associated with a high risk of long-term cardiovascular events. Previous studies have shown that curcuminoids decreased myocardial injury post-coronary bypass graft surgery through anti-oxidant and anti-inflammatory effects. We sought to examine whether curcuminoids could prevent PCI-related myocardial injury. One-hundred enrolled patients receiving elective PCI were randomized to obtain curcuminoids or placebo 4 g/day at least 1 day before and after the scheduled PCI. Cardiac troponin-T and 12-lead electrocardiogram were evaluated before PCI and at 24 and 48 h post-PCI. The definitions of PCI-related myocardial injury and myocardial infarction were in line with the third universal definition of myocardial infarction. Baseline characteristics of patients and procedures did not differ between the curcuminoids and placebo groups. The mean age was 63.9 ± 10.8 years. The incidence of PCI-related myocardial injury was not different between curcuminoids and placebo groups (32% vs. 38%, P = .675). The peak high-sensitive cardiac troponin T levels after PCI were not different between the curcuminoids and placebo groups (201.0 ± 547.0 ng/L vs. 187.0 ± 703.9 ng/L respectively, P = .912). Further, the high-sensitive C-reactive protein levels post-PCI were similar in patients receiving curcuminoids and placebo (7.2 ± 18.8 mg/dL vs. 6.6 ± 17.5 mg/dL, respectively, P = .873). We found that short-term treatment with curcuminoids did not reduce the occurrence of PCI-related myocardial injury. We did not observe the role of anti-oxidative and anti-inflammatory effects of curcuminoids in the PCI-related myocardial injury.

Chronic total occlusion or non-chronic total occlusion percutaneous coronary intervention: Do myocytes really care?

Chronic total occlusions subtend a more extensive perfusion defect size compared to non-chronic total occlusion lesions. Chronic total occlusion percutaneous coronary intervention (CTO PCI) results in significant improvement in myocardial blood flow and reduction in perfusion defect size. Improvement in hyperemic myocardial blood Flow (MBF), coronary flow reserve (CFR) and perfusion defect size is comparable in CTO and hemodynamically significant non-CTO PCI.

Adverse events in patients with high platelet reactivity following successful chronic total occlusion PCI: The Assessment of Dual AntiPlatelet Therapy with Drug-Eluting Stents (ADAPT-DES) study

BACKGROUND

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) typically requires a greater number of stents and longer stent length than non-CTO PCI, placing these patients at greater risk for adverse ischemic events. We sought to determine whether the association between high platelet reactivity (HPR) and the risk of ischemic events is stronger after CTO than non-CTO PCI.

METHODS

Patients undergoing successful PCI in the multicenter ADAPT-DES study were stratified according to whether they underwent PCI of a CTO. HPR was defined as VerifyNow platelet reaction units >208. The study primary endpoint was the 2-year risk target vessel failure ([TVF] defined as cardiac death, myocardial infarction, or target lesion revascularization).

RESULTS

CTO PCI was performed in 400 of 8448 patients. HPR was present in 34.5% of CTO PCI patients and 43.1% of non-CTO PCI patients (P = .0007). Patients undergoing CTO PCI with versus without HPR had significantly higher 2-year rates of TVF (15.0% versus 8.3%, P = .04) without significant differences in bleeding. HPR was an independent predictor of 2-year TVF (adjusted HR 1.16, 95% CI 1.02-1.34, P = .03) whereas CTO PCI was not (adjusted HR 0.89, 95% CI 0.65-1.22, P = .48). There was a significant interaction between CTO versus non-CTO PCI and PRU as a continuous variable for 2-year TVF (P_interaction = 0.02).

CONCLUSIONS

In ADAPT-DES, HPR was associated with an increased 2-year risk of TVF after PCI, an association that was at least as strong after CTO PCI compared with non-CTO PCI.

Anti-anginal medication titration among patients with residual angina 6-months after chronic total occlusion percutaneous coronary intervention: insights from OPEN CTO registry

Aims

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has been shown to reduce angina and improve quality of life, but the frequency of new or residual angina after CTO PCI and its relationship with titration of anti-anginal medications (AAMs) has not been described.

Methods and results

Among consecutive CTO PCI patients treated at 12 US centres in the OPEN CTO registry, angina was assessed 6 months after the index PCI using the Seattle Angina Questionnaire (SAQ) Angina Frequency scale (a score <100 defined new or residual angina). We then compared the proportion of patients with AAM escalation (defined as an increase in the number or dosage of AAMs between discharge and follow-up) between those with and without 6-month angina. Of 901 patients who underwent CTO PCI, 197 (21.9%) reported angina at 6-months, of whom 80 (40.6%) had de-escalation, 66 (33.5%) had no change, and only 51 (25.9%) had escalation of their AAM by the 6-month follow-up. Rates of AAM escalation were similar when stratifying patients by the ultimate success of the CTO PCI, completeness of physiologic revascularization, presence or absence of angina at baseline, history of heart failure, and by degree of symptomatic improvement after CTO PCI.

Conclusions

One in five patients reported angina 6 months after CTO PCI. Although patients with new or residual angina were more likely to have escalation of AAMs in follow-up compared with those without residual symptoms, only one in four patients with residual angina had escalation of AAMs. Although it is unclear whether this finding reflects maximal tolerated therapy at baseline or therapeutic inertia, these findings suggest an important potential opportunity to further improve symptom control in patients with complex stable ischaemic heart disease.

Percutaneous Coronary Intervention of Chronic Total Occlusions in Patients with Diabetes Mellitus: a Treatment-Risk Paradox

PURPOSE OF REVIEW

Diabetes mellitus (DM) is highly prevalent among patients undergoing percutaneous coronary intervention (PCI) for chronic total occlusions (CTOs). This review aims to summarize the available evidence on CTO recanalization in patients with DM.

RECENT FINDINGS

Coronary artery bypass grafting (CABG) surgery is the recommended revascularization modality for patients with DM and multivessel coronary artery disease (CAD). However, the optimal management strategy in diabetic patients with CTO and single-vessel disease or prior CABG remains a clinical dilemma. Contemporary, large-scale, observational registries support the notion that CTO PCI, if performed at high-volume CTO PCI centers by highly experienced operators, conveys similar high procedural success and low complication rates in patients with and without DM. Although DM patients have more frequently CTOs and may derive greater benefit from complete revascularization, they are less frequently exposed to CTO PCI than non-DM patients (treatment-risk paradox). CTO PCI performed by highly experienced operators constitutes a safe and effective treatment option for selected diabetic CTO patients who are not candidates for CABG. Randomized studies are warranted to compare long-term outcomes of CTO PCI and medical therapy in this high-risk subset.

Impact of diabetes mellitus on 5-year clinical outcomes in patients with chronic total occlusion lesions

BACKGROUND

Diabetes mellitus (DM) is a major predictor of cardiovascular morbidity and mortality. However, there are limited data on the impact of DM in patients who have chronic total occlusion (CTO) lesion on long-term outcomes.

PATIENTS AND METHODS

A total of 822 CTO patients who underwent coronary angiography, treated by either percutaneous coronary intervention or optimal medical therapy, were enrolled and divided into two groups: (i) diabetic group (n=363) and (ii) nondiabetic group (n=459). Individual and composite major clinical outcomes were compared up to 5 years.

RESULTS

Propensity score matching analysis was carried out generating two groups (298 pairs, n=596, C-statistic=0.655) with balanced baseline characteristics. Up to 5 years, the DM group showed a higher trend toward revascularization (19.5 vs. 13.5%, P=0.051) and major adverse cardiovascular events (MACE) (24.7 vs. 19.1%, P=0.097) compared with the nondiabetic group. However, there was no difference in the incidence of death and myocardial infarction between the two groups. Subgroup analysis showed that the chronic kidney disease (CKD) subgroup was associated with a higher incidence of all-cause death, cardiac death, myocardial infarction, revascularization, and MACE in comparison with diabetic patients without CKD and nondiabetic patients, respectively (total MACE: 39 vs. 20.5 vs. 19.2% , P=0.001). Insulin-dependent diabetic patients had a significantly higher incidence of MACE (hazard ratio=1.58; 95% confidence interval: 1.04-2.40; P=0.03) compared with the nondiabetic patients.

CONCLUSION

Diabetic patients with CTO were associated with a trend toward a higher incidence of revascularization and total MACE up to 5 years. Insulin-dependent and diabetic patients with CKD subgroups had a significantly higher incidence of total MACE.

Contemporary Approach to Chronic Total Occlusion Interventions

PURPOSE OF REVIEW

Chronic total occlusion (CTO) poses one of the greatest technical challenges to interventional cardiologists. Despite recent advancements in techniques and clinical trials showing significant benefits of CTO percutaneous coronary interventions (PCI), the proportion of patients with untreated CTOs remains high. We therefore aim to perform a comprehensive review of the various techniques available, recent advancements, benefits, and complications associated with CTO PCI.

RECENT FINDINGS

Three randomized clinical trials examining the benefits of CTO PCI have recently been presented. Scoring systems have been developed to facilitate pre-procedural estimation of success and complications of CTO PCI. Technological enhancements in coronary wires and other interventional equipment along with dedicated training for CTO operators have improved the likelihood of successful recanalization of CTOs. CTO PCI has been shown to improve patient symptoms and quality of life. It is therefore important to have an in-depth knowledge of the various CTO techniques, appropriate equipment, and complications when performing these complex procedures. Clinicians should weigh the risks and benefits and choose the appropriate patient population who may benefit from revascularization.