CrossBoss Catheter Research Articles

Randomized Comparison of a CrossBoss First Versus Standard Wire Escalation Strategy for Crossing Coronary Chronic Total Occlusions: The CrossBoss First Trial

ObjectivesThe authors performed a multicenter, randomized-controlled, clinical trial comparing upfront use of the CrossBoss catheter versus antegrade wire escalation for antegrade crossing of coronary chronic total occlusions. BackgroundThere is equipoise about the optimal initial strategy for crossing coronary chronic total occlusions. MethodsThe primary endpoints were the time required to cross the chronic total occlusion or abort the procedure and the frequency of procedural major adverse cardiovascular events. The secondary endpoints were technical and procedural success, total procedure time, fluoroscopy time required to cross and total fluoroscopy time, total air kerma radiation dose, total contrast volume, and equipment use. ResultsBetween 2015 and 2017, 246 patients were randomized to the CrossBoss catheter (n = 122) or wire escalation (n = 124) at 11 U.S. centers. The baseline clinical and angiographic characteristics of the study groups were similar. Technical and procedural success were 87.8% and 84.1%, respectively, and were similar in the 2 groups. Crossing time was similar: 56 min (interquartile range: 33 to 93 min) in the CrossBoss group and 66 min (interquartile range: 36 to 105 min) in the wire escalation group (p = 0.323), as was as the incidence of procedural major adverse cardiovascular events (3.28% vs. 4.03%; p = 1.000). There were no significant differences in the secondary study endpoints. ConclusionsAs compared with wire escalation, upfront use of the CrossBoss catheter for antegrade crossing of coronary chronic total occlusions was associated with similar crossing time, similar success and complication rates, and similar equipment use and cost.

Use of antegrade dissection re-entry in coronary chronic total occlusion percutaneous coronary intervention in a contemporary multicenter registry.

We assessed efficacy and safety of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) using antegrade dissection re-entry (ADR). We examined outcomes of ADR among 1313 CTO PCIs performed at 11 US centers between 2012-2015. 84.1% of patients were men. Prevalence of prior coronary artery bypass graft surgery was 34.3%. Overall technical and procedural success were 90.1% and 88.7%, respectively. In-hospital major adverse cardiovascular events (MACE) occurred in 31 patients (2.4%). ADR was used in 458 cases (34.9%), and was the first strategy in 169 cases (12.9%). ADR cases were angiographically more complex than non-ADR cases (mean J-CTO score: 2.8±1.2 vs. 2.4±1.2, p<0.001). ADR was performed using the CrossBoss catheter in 246 of 458 (53.7%) and the Stingray system in 251 ADR cases (54.8%). Compared with non-ADR cases, ADR cases had lower technical (86.9% vs. 91.8%, p=0.005) and procedural success (85.0% vs. 90.7%, p=0.002), but similar risk for MACE (2.9% vs. 2.2%, p=0.42). ADR was associated with longer procedure and fluoroscopy time, and higher patient air kerma dose and contrast volume (all p<0.001). After excluding retrograde cases, ADR and antegrade wire escalation (AWE) had similar technical success (92.7% vs. 94.2%, p=0.43), procedural success (91.8% vs. 94.1%, p=0.23), and MACE (2.1% vs. 0.6%, p=0.12). ADR is used relatively frequently in contemporary CTO PCI, especially for challenging lesions and after failure of other strategies. ADR is associated with similar success rates and risk for complications as compared with AWE, and is important for achieving high procedural success.

Advances in procedural techniques--antegrade.

There have been many technological advances in antegrade CTO PCI, but perhaps most importantly has been the evolution of the “hybrid’ approach where ideally there exists a seamless interplay of antegrade wiring, antegrade dissection re-entry and retrograde approaches as dictated by procedural factors. Antegrade wire escalation with intimal tracking remains the preferred initial strategy in short CTOs without proximal cap ambiguity. More complex CTOs, however, usually require either a retrograde or an antegrade dissection re-entry approach, or both. Antegrade dissection re-entry is well suited to long occlusions where there is a healthy distal vessel and limited “interventional” collaterals. Early use of a dissection re-entry strategy will increase success rates, reduce complications, and minimise radiation exposure, contrast use as well as procedural times. Antegrade dissection can be achieved with a knuckle wire technique or the CrossBoss catheter whilst re-entry will be achieved in the most reproducible and reliable fashion by the Stingray balloon/wire. It should be avoided where there is potential for loss of large side branches. It remains to be seen whether use of newer dissection re-entry strategies will be associated with lower restenosis rates compared with the more uncontrolled subintimal tracking strategies such as STAR and whether stent insertion in the subintimal space is associated with higher rates of late stent malapposition and stent thrombosis. It is to be hoped that the algorithms, which have been developed to guide CTO operators, allow for a better transfer of knowledge and skills to increase uptake and acceptance of CTO PCI as a whole.

A novel approach to the management of occlusive in-stent restenosis (ISR)

Chronic total occlusions (CTO) secondary to in-stent restenosis (ISR) represent challenging lesions with low PCI success rates. The CrossBoss is an over-the-wire blunt catheter which has emerged as a useful tool in occlusive ISR. We aimed to review the utility of this device in the treatment of occlusive ISR within the United Kingdom. The CrossBoss catheter was used as the primary strategy in 30 patients (31 CTOs) with a median CTO duration of 24 months, a mean CTO length of 39 mm and a previous unsuccessful PCI attempt in 48% of cases. Procedural success was 90% (27/30) and the CrossBoss catheter directly facilitated success in 81% of cases, with direct lumen-to-lumen crossing of the catheter in most cases. Identifiable predictors of failure were evident in the unsuccessful cases. When successful, crossing time was short (median eight minutes, range one to 40 minutes), as were procedural time (mean 99±29 minutes) and fluoroscopy time (mean 26.9±12.2 minutes), whilst radiation dose (median 5,738 cGycm2, range 3,430-64,122 cGycm2) and contrast dose (mean 271±79 mL) were low. There were no procedural complications. In our experience, use of the CrossBoss catheter is associated with high procedural success rates, short crossing times and low complication rates in the setting of occlusive ISR.

059 IMPACT OF PROCTORING AND NEW TECHNIQUES ON SUCCESS RATES FOR OPERATORS UNDERTAKING PERCUTANEOUS INTERVENTION OF CHRONIC TOTAL OCCLUSIONS

Background The incidence of chronic total occlusion (CTO) in coronary arteries can be as high as 35%. These lesions are considered technically challenging. New tools and techniques have been developed to aid in re-opening these lesions and may contribute to increased interventional success rates. Aim To assess methods utilised for Percutaneous Intervention (PCI) of coronary CTOs at our regional tertiary cardiac centre and determine the effect of proctoring on success rates. Methods: Our tertiary centre performs 1200 PCIs annually. Nationally recognised experts in CTO PCI attended as proctors on three separate occasions over a period of 4 months. They demonstrated the use of the CrossBoss catheter and the Sting Ray balloon in selected cases to three of the seven local PCI operators. Success rates and techniques of the operators who had been proctored were compared to those who were pre or non-proctored. Sequential patients who underwent PCI for CTO in 2011 and 2012 were included in the analysis. Those who did not meet the criteria for definition of (‘true’ or ‘functional’) CTO or whose occlusion was in the infarct related artery in the context of an ST Elevation Myocardial Infarction (STEMI) were excluded. Disparity in the definition of a CTO was corroborated or refuted by a second independent observer. The latter was further confirmed by a third independent observer. Data was collected retrospectively from the British Cardiovascular Intervention Society (BCIS) audit database. The Japanese-CTO (J-CTO) score was applied retrospectively to all patients. Continuous variables were presented as mean (±SD) and categorical variables as percentage. The χ 2 test or Fisher9s exact test was utilised for testing the difference between categorical variables. Results There were 116 patients in total (n=59 for proctored operators and n=57 for pre/non-proctored operators), mean age was 60.8 years (±11) for the former group and 64.8 years (±11) for the latter group with a greater percentage of female patients in the latter (11.8%, n=7/59 vs 19.3%, n=11/57, p=0.31). Operators who were proctored saw a significant increase in their overall success rates in 2012 compared to non/pre-proctored operators (77.9%, n=46/59 vs 54.3%, n=31/57, p=0.010, respectively). Proctored operators were more likely to use antegrade dissection/re-entry, new tools (eg, Tornus, microcatheters) or the retrograde technique in attempts to re-open CTOs. This was significantly associated with greater success rates in all patients, irrespective of J-CTO score (65.2%, n=30/46 vs 18.75%, 6/31, p Conclusion In this observational study, proctoring was associated with a significant increase in subsequent technical success. This is mostly accounted for by results in the complex cases with J-CTO scores ≥2 where success rates increased from 28% to 70%.

Use of the crossboss catheter in coronary chronic total occlusion due to in‐stent restenosis

We describe treatment of six chronic total occlusions due to in-stent restenosis with the CrossBoss catheter (BridgePoint Medical, Minneapolis, Minnesota). The CrossBoss catheter allowed successful CTO crossing in 5 of 6 lesions (83%): in 50% the catheter entered the distal true lumen, whereas in 33% a wire was required for distal true lumen crossing. No complications were observed. Use of the CrossBoss catheter can facilitate treatment of coronary chronic total occlusions due to in-stent restenosis.

Use of the CrossBoss catheter for crossing superficial femoral artery chronic total occlusions

The CrossBoss chronic total occlusion catheter has been developed for the treatment of coronary chronic total occlusions. We report a novel use of the CrossBoss catheter for the crossing of a superficial femoral artery chronic total occlusion in three patients after conventional guidewire techniques failed.