Procedural characteristics and outcomes following chronic total occlusion coronary intervention: pooled analysis from 5 registries

BACKGROUND

Recent improvements in clinical skills, technology, and hardware have resulted in improved success rates with chronic total occlusion (CTO) percutaneous coronary intervention (PCI). We performed a study level pooled analysis from the five largest registries of percutaneous coronary intervention (PCI) of CTO.

RESEARCH DESIGN AND METHODS

We conducted pooled analysis of 9500 patients in registries and data on procedural characteristics, technical success, and MACCE was collected.

RESULTS

A total of 9500 patients were included in the analysis. Mean age was 65.4 years with previous CABG in 24.8%, reattempt procedure in 24.8% and mean JCTO score was 2.2. Final wiring strategy in hybrid algorithm-based registries was AWE in 40.8-58%, Retrograde in 24-35%, ADR in 16-25% and in Expert JCTO and EURO CTO was AWE in 72-75% and retrograde in 25-28%. Technical success was achieved in 87.8%. In hospital MACCE was 2.5% (95% CI: 1.8- 3.4%), mortality 0.44% (95% CI: 0.23-0.84%), stroke 0.2% (95% CI: 0.1-0.3%); myocardial infraction 1.6% (95% CI: 1.1-2.2%); and cardiac tamponade 0.8% (95% CI: 0.5 to 1.3%).

CONCLUSION

CTO PCI is currently performed with high technical success rates and low complication rates in experienced hands utilizing various techniques.

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.

Advances in percutaneous coronary intervention for chronic total occlusions: current antegrade dissection and reentry techniques and updated algorithm

Percutaneous coronary intervention (PCI) for chronic total occlusions (CTO) is considered relatively complex with low success rates and high complication rates. Treating a CTO with PCI using the hybrid algorithm increases success rates with acceptable complication rates. An essential part of the hybrid algorithm is antegrade dissection and reentry (ADR). In PCI of a non-CTO coronary lesion, the guidewire over which the stent is advanced and placed stays within the true lumen of the coronary artery. ADR techniques make it possible to cross the lesion through the wall of the coronary artery, the subintimal space, thus creating a small bypass within the architecture of the coronary artery and restoring antegrade blood flow. ADR increases success rates, especially in more difficult CTO procedures. In the last decade, new materials and techniques have been introduced in quick succession, which are summarised in this review. Consequently an updated ADR algorithm is presented, which can support the CTO operator during an ADR procedure.

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.

The Hybrid Approach to Chronic Total Occlusion Percutaneous Coronary Intervention: Update From the PROGRESS CTO Registry

OBJECTIVES

The aim of this study was to determine the techniques and outcomes of hybrid chronic total occlusion (CTO) percutaneous coronary intervention (PCI) in a diverse group of patients and operators on 2 continents.

BACKGROUND

CTO PCI has been evolving with constant improvement of equipment and techniques.

METHODS

Contemporary outcomes of CTO PCI were examined by analyzing the clinical, angiographic, and procedural characteristics of 3,122 CTO interventions performed in 3,055 patients at 20 centers in the United States, Europe, and Russia.

RESULTS

The mean age was 65 ± 10 years, and 85% of the patients were men, with high prevalence of diabetes (43%), prior myocardial infarction (46%), prior coronary artery bypass graft surgery (33%), and prior PCI (65%). The CTO target vessels were the right coronary artery (55%), left anterior descending coronary artery (24%), and left circumflex coronary artery (20%). The mean J-CTO (Multicenter Chronic Total Occlusion Registry of Japan) and PROGRESS CTO (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention) scores were 2.4 ± 1.3 and 1.3 ± 1.0, respectively. The overall technical and procedural success rate was 87% and 85%, respectively, and the rate of in-hospital major complications was 3.0%. The final successful crossing strategy was antegrade wire escalation in 52.0%, retrograde in 27.1%, and antegrade dissection re-entry in 20.9%; >1 crossing strategy was required in 40.9%. Median contrast volume, air kerma radiation dose, and procedure and fluoroscopy time were 270 ml (interquartile range: 200 to 360 ml), 2.9 Gy (interquartile range: 1.7 to 4.7 Gy), 123 min (interquartile range: 81 to 188 min) and 47 min (interquartile range: 29 to 77 min), respectively.

CONCLUSIONS

CTO PCI is currently being performed with high success and acceptable complication rates among various experienced centers in the United States, Europe, and Russia. (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention [PROGRESS CTO]; NCT02061436).

Outcomes With the Use of the Retrograde Approach for Coronary Chronic Total Occlusion Interventions in a Contemporary Multicenter US Registry

BACKGROUND

We sought to examine the efficacy and safety of chronic total occlusion percutaneous coronary intervention using the retrograde approach.

METHODS AND RESULTS

We compared the outcomes of the retrograde versus antegrade-only approach to chronic total occlusion percutaneous coronary intervention among 1301 procedures performed at 11 experienced US centers between 2012 and 2015. The mean age was 65.5±10 years, and 84% of the patients were men with a high prevalence of diabetes mellitus (45%) and previous coronary artery bypass graft surgery (34%). Overall technical and procedural success rates were 90% and 89%, respectively, and in-hospital major adverse cardiovascular events occurred in 31 patients (2.4%). The retrograde approach was used in 539 cases (41%), either as the initial strategy (46%) or after a failed antegrade attempt (54%). When compared with antegrade-only cases, retrograde cases were significantly more complex, both clinically (previous coronary artery bypass graft surgery prevalence, 48% versus 24%; P<0.001) and angiographically (mean Japan-chronic total occlusion score, 3.1±1.0 versus 2.1±1.2; P<0.001) and had lower technical success (85% versus 94%; P<0.001) and higher major adverse cardiovascular events (4.3% versus 1.1%; P<0.001) rates. On multivariable analysis, the presence of suitable collaterals, no smoking, no previous coronary artery bypass graft surgery, and left anterior descending artery target vessel were independently associated with technical success using the retrograde approach.

CONCLUSIONS

The retrograde approach is commonly used in contemporary chronic total occlusion percutaneous coronary intervention, especially among more challenging lesions and patients. Although associated with lower success and higher major adverse cardiovascular event rates in comparison to antegrade-only crossing, retrograde percutaneous coronary intervention remains critical for achieving overall high success rates.

Impact of diabetes mellitus on acute outcomes of percutaneous coronary intervention in chronic total occlusions: insights from a US multicentre registry

AIM

To examine the impact of diabetes mellitus on procedural outcomes of patients who underwent percutaneous coronary intervention for chronic total occlusion.

METHODS

We assessed the impact of diabetes mellitus on the outcomes of percutaneous coronary intervention for chronic total occlusion among 1308 people who underwent such procedures at 11 US centres between 2012 and 2015.

RESULTS

The participants' mean ± sd age was 66 ± 10 years, 84% of the participants were men and 44.6% had diabetes. As compared with participants without diabetes, participants with diabetes were more likely to have undergone coronary artery bypass graft surgery (38 vs 31%; P = 0.006), and to have had previous heart failure (35 vs 22%; P = 0.0001) and peripheral arterial disease (19 vs 13%; P = 0.002). They also had a higher BMI (31 ± 6 kg/m² vs 29 ± 6 kg/m² ; P = 0.001), similar Japanese chronic total occlusion scores (2.6 ± 1.2 vs 2.5 ± 1.2; P = 0.82) and similar final successful crossing technique: antegrade wire escalation (46 vs 47%; P = 0.66), retrograde (30 vs 28%; P = 0.66) and antegrade dissection re-entry (24 vs 25%; P = 0.66). Technical (91 vs 90%; P = 0.80) and procedural (89 vs 89%; P = 0.93) success was similar in the two groups, as was the incidence of major adverse cardiac events (2.2 vs 2.5%; P = 0.61).

CONCLUSIONS

In a contemporary cohort of people undergoing percutaneous coronary intervention for chronic total occlusion, nearly one in two (45%) had diabetes mellitus. Procedural success and complication rates were similar in people with and without diabetes.

One-year outcomes after successful chronic total occlusion percutaneous coronary intervention: The impact of dissection re-entry techniques

We aimed to determine clinical outcomes 1 year after successful chronic total occlusion (CTO) PCI and, in particular, whether use of dissection and re-entry strategies affects clinical outcomes. Hybrid approaches have increased the procedural success of CTO percutaneous coronary intervention (PCI) but longer-term outcomes are unknown, particularly in relation to dissection and re-entry techniques. Data were collected for consecutive CTO PCIs performed by hybrid-trained operators from 7 United Kingdom (UK) centres between 2012 and 2014. The primary endpoint (death, myocardial infarction, unplanned target vessel revascularization) was measured at 12 months along with angina status. One-year follow up data were available for 96% of successful cases (n = 805). In total, 85% of patients had a CCS angina class of 2-4 prior to CTO PCI. Final successful procedural strategy was antegrade wire escalation 48%; antegrade dissection and re-entry (ADR) 21%; retrograde wire escalation 5%; retrograde dissection and re-entry (RDR) 26%. Overall, 47% of CTOs were recanalized using dissection and re-entry strategies. During a mean follow up of 11.5 ± 3.8 months, the primary endpoint occurred in 8.6% (n = 69) of patients (10.3% (n = 39/375) in DART group and 7.0% (n = 30/430) in wire-based cases). The majority of patients (88%) had no or minimal angina (CCS class 0 or 1). ADR and RDR were used more frequently in more complex cases with greater disease burden, however, the only independent predictor of the primary endpoint was lesion length. CTO PCI in complex lesions using the hybrid approach is safe, effective and has a low one-year adverse event rate. The method used to recanalize arteries was not associated with adverse outcomes. © 2017 Wiley Periodicals, Inc.

The first clinical experience with a novel "locking" microcatheter in chronic coronary total occlusions

AIMS

A novel "locking" microcatheter has been developed to address residual failure modes in chronic total occlusion (CTO) percutaneous coronary intervention (PCI). The aim of this study was to report the first clinical experience of this device.

METHODS AND RESULTS

The microcatheter was assessed prospectively in 92 unselected CTO cases across six European sites. Overall technical success was 85.9% (79/92) and 97.5% for patients with a J-CTO score of <3 (39/40). Within-CTO tortuosity was the only lesion characteristic to predict reduced technical success (OR 0.10 [0.01-0.97], p=0.047). Calcification (OR 0.45 [0.04-5.31], p=0.53), lesion length >20 mm (OR 0.58 [0.05-6.81], p=0.66) and a blunt proximal cap (OR 0.47 [0.08-2.90], p=0.42) were not associated with technical failure in this case series. Locking facilitated guidewire crossing (after initial failure) of the proximal cap in 23 cases, distal cap in 11 cases and CTO body in 10 cases, and delivery of the microcatheter through to the distal vessel in 22 cases. The overall procedural complication rate was 1.1% (1/92) with no major events.

CONCLUSIONS

Guidewire locking with this novel microcatheter assists penetration and crossing of fibrocalcific anatomy with a high degree of safety. Using this device in CTO PCI may lead to improved primary wiring and overall procedural success rates.

Retrograde Approach is as Effective and Safe as Antegrade Approach in Contemporary Percutaneous Coronary Intervention for Chronic Total Occlusion: A Taiwan Single-Center Registry Study

BACKGROUND

In percutaneous coronary intervention (PCI) for chronic total occlusion (CTO), most experts regard the antegrade approach as the default initial strategy, reserving the retrograde approach for reattempts following antegrade failure. In this study, we aimed to compare the efficacy and safety between the antegrade and retrograde approaches in CTO PCI.

RESULTS

Between 2012 and 2013, patients that underwent 321 consecutive attempts by high-volume operators (> 75 total CTO PCI cases during the period) in a tertiary university-affiliated hospital were enrolled. The antegrade approach was used in 152 patients, and retrograde in 169 patients. The duration of occlusion was significantly longer and the J-CTO score higher in the retrograde group. Technical success was achieved in 148 patients of the antegrade group (97.4%), and 163 patients in the retrograde group (96.4%) (p = 0.75). A major procedural complication occurred in 3 patients of the antegrade group (2.0%) and in 6 patients of the retrograde group (3.6%) (p = 0.51). In-hospital major adverse cardiac events (MACE) rates (antegrade 0.7%, n = 152; retrograde 0.6%, n = 169) were comparable. The procedure and fluoroscopy times were significantly longer, with more radiation exposure and contrast medium consumption, in the retrograde group. In the retrograde group, similar success, procedural complication and in-hospital MACE rates were achieved in the 3 collateral subgroups.

CONCLUSIONS

In selected cases and with highly experienced operators, retrograde approach in CTO PCI is as effective and safe as antegrade approach at the expense of longer procedure time, more radiation exposure and contrast medium consumption. For retrograde approach, either septal, epicardial or AV groove collaterals can be used with similarly success, complication and in-hospital MACE rates.

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.

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.

The Hybrid Approach to Intervention of Chronic Total Occlusions

The “hybrid” approach to chronic total occlusion (CTO) percutaneous coronary intervention (PCI) was developed to provide guidance on optimal crossing strategy selection. Dual angiography remains the cornerstone of clinical decision making in CTO PCI. Four angiographic parameters are assessed: (a) morphology of the proximal cap (clear-cut or ambiguous); (b) oc-clusion length; (c) distal vessel size and presence of bifurcations beyond the distal cap; and (d) location and suitability of a retrograde con-duit (collateral channels or bypass grafts) for retrograde access. Antegrade wire escalation is favored for short (<20 mm) occlusions, usually escalating rapidly from a soft tapered-tip polymer-jacketed guidewire to a stiff polymer-jacketed or tapered-tip guidewire. Antegrade dissection/re-entry is favored in long (≥20 mm long) occlusions, try-ing to minimize the dissection length by re-entering into the distal true lumen immediately after the occlusion. Primary retro-grade approach is preferred for lesions with an ambiguous proximal cap, poor distal target, good interventional collaterals, and heavy calcification, as well as chronic kidney disease. The “hybrid” approach advocates early change between strategies to enable CTO crossing in the most efficacious, efficient, and safe way. Several early studies are demonstrating high success and low complication rates with use of the “hybrid” approach, supporting its expanding use in CTO PCI. .

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.

Procedural failure of chronic total occlusion percutaneous coronary intervention: Insights from a multicenter US registry

BACKGROUND

The hybrid approach to chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has significantly increased procedural success rates, yet some cases still fail. We sought to evaluate the causes of failure in a contemporary CTO PCI registry.

METHODS

We examined 380 consecutive patients who underwent CTO-PCI at 4 high volume CTO PCI centers in the United States using the "hybrid" approach. Clinical, angiographic, complication, and efficiency outcomes were compared between successful and failed cases. Failed cases were individually reviewed by an independent reviewer to determine the cause of failure.

RESULTS

Procedural success was 91.3%. Compared with patients in whom CTO PCI was successful, those in whom CTO PCI failed had similar baseline clinical characteristics, but were more likely to have longer occlusion length, more tortuosity, more proximal cap ambiguity and blunt stump, and higher mean J-CTO scores (2.8 ± 1.1 vs. 3.5 ± 1.0, P < 0.001), and less likely to have collaterals suitable for the retrograde approach (66% vs. 45%, P = 0.021). Failure was due to a complication in 10 cases (30%). In the remaining 23 cases (70%) failure was due to inability to wire the lesion (n = 21, 4 of which were CTOs due to in-stent restenosis), or poor antegrade flow after PCI (n = 5).

CONCLUSIONS

Compared with successful cases, failed CTO-PCI cases are more likely to have higher J-CTO scores, longer occlusion length, ambiguous proximal cap and no appropriate collaterals for retrograde crossing. Development of novel CTO crossing techniques is needed to further increase CTO PCI success rates.

Advances in the management of coronary chronic total occlusions

Chronic total occlusions (CTOs) have been called "the last frontier" of percutaneous coronary intervention (PCI) due to traditionally low success rates and high risk for restenosis and re-occlusion. Recent advances in equipment and crossing techniques have significantly increased CTO PCI success rates while maintaining low risk of complications. Specifically, the retrograde approach and controlled antegrade dissection and re-entry in conjunction with advanced guidewires and microcatheters have significantly improved procedural success rates. Moreover, the introduction of the "hybrid" approach has created a unified framework for operators to approach CTOs in a systematic and efficient fashion. Finally, drug-eluting stents, especially second generation, have improved long-term patency after CTO PCI.

Percutaneous Treatment of Coronary Chronic Total Occlusion Part 2: Technical Approach

Dual injection is recommended for nearly all chronic total occlusion (CTO) percutaneous coronary intervention (PCI) to determine the optimal crossing strategy and guide wire advancement into the distal true lumen. Strategies that provide enhanced guide catheter support (such as long sheaths, large-bore guiding catheters, use of guide catheter extensions, and anchor techniques) are important for maximising the success rate and efficiency of CTO PCI. Use of a microcatheter or over-the-wire balloon is strongly recommended in CTO PCI for enhancing the penetrating power of the guidewire, enabling change in tip shape and allowing guidewire change (stiff CTO guidewires are not optimal for crossing non-occluded coronary segments). Adherence to a procedural strategy that standardises CTO technique and facilitates procedural success is recommended. Such a strategy would permit stepwise decision-making for antegrade and retrograde methods; inform guidewire selection; and incorporate alternative approaches for instances of initial failure. Given the paucity of long-term outcomes with use of novel crossing techniques (antegrade dissection/re-entry and retrograde), antegrade wire escalation is the preferred CTO crossing technique, if technically feasible. Using measures to minimise radiation exposure (including but not limited to use of 7.5 frames per second fluoroscopy and use of low magnification) and contrast administration is recommended. CTO PCI is best performed at centres with dedicated CTO PCI experience and expertise. Use of crossing difficulty prediction tools, such as the J-CTO score, can facilitate the selection of cases with a high likelihood of quick crossing that can be attempted at less experienced centres.