Chronic Total Occlusion Length Research Articles

Clinical validity of the Japanese below-the-knee chronic total occlusion scoring system for the prediction of successful guidewire crossing

ObjectiveTo validate the Japanese below-the-knee (J-BTK) chronic total occlusion (CTO) score for the prediction of successful guidewire crossing (S-GC) in angiographic evaluation. MethodsA prospective, multicenter, nonrandomized study examined 751 consecutive BTK CTOs in 497 patients treated with endovascular therapy in 16 Japanese medical centers from April 2021 to March 2022. The cohort was classified into 2 groups: an S-GC group and a failed guidewire crossing group. ResultsThe J-BTK CTO score, which assigned one point to “Blunt type at the proximal entry point,” one point to “Calcification at the proximal entry point,” one point to “Reference vessel diameter <2.0 mm,” one point to “CTO length ≥200 mm,” and two points to “No outflow of the target vessel,” was used to categorize BTK CTOs into 4 grades with varying probabilities of S-GC: grade A (J-BTK CTO score of 0 and 1), grade B (score of 2 and 3), grade C (score of 4 and 5), and grade D (score of 6). Rates of S-GC in each grade (grades A, B, C, and D) were 97.5%, 89.1%, 62.5%, and 27.3%, respectively. The area under the receiver-operating characteristic curve for S-GC was 0.8304. Although the previous J-BTK CTO study enrolled only de novo lesions, both de novo and restenotic lesions were evaluated in this study. De novo lesions have a lower chance of S-GC (odds ratio: 0.24, 95% confidence interval: 0.09-0.67) in the multivariate analysis, and the area under the receiver-operating characteristic curve of the modified J-BTK CTO score, which additionally assigned two points to “De novo lesion,” was 0.846. The modified J-BTK CTO score showed an appropriate calibration (Hosmer-Lemeshow P = .957). ConclusionsThe J-BTK CTO score and the modified J-BTK CTO score predict the probability of an S-GC of BTK CTOs and stratify the difficulty of endovascular therapy for BTK CTOs in angiographic evaluation.

New scoring system for predicting percutaneous coronary intervention of chronic total occlusion success: Impact of operator's experience.

Several scoring systems have been developed in order to predict percutaneous coronary intervention (PCI) result of chronic total occlusion (CTO). The scores principally include anatomic and clinical variables. Operator experience is a decisive factor for achieving successful result. We sought to assess the real impact of operator growing experience on CTO-PCI success. The angiographic and clinical variables of CTO-PCIs performed in our center between May 2007 and April 2021 were collected, and variables with potential association with procedural result were thoroughly reviewed. The influence of operator experience based on the number of previous CTO-PCIs was statistically assessed. A scoring system with combination of anatomic variables and operator experience was devised. A total of 540 PCIs in 457 patients were performed in our institution. The scoring model was developed from the derivation set (2/3 of the cohort). The final variables in logistic regression model were CTO length ≥ 20 mm, blunt stump, vessel tortuosity > 45o and operator experience < 100 PCIs. The model showed good performance in the derivation set (area under curve [AUC]: 0.768; confidence interval [CI]: 0706-0.830; p < 0.001) with no significant shrinkage in the validation set (AUC: 0.704; CI: 0.613-0.796; p < 0.001). This new score (E-CTO score) adequately predict the probability of CTO-PCI failure. The model includes a variable representing operator experience along with other anatomic variables.

Prevalence, predictors, and management for balloon uncrossable or undilatable lesions in patients undergoing percutaneous coronary intervention with in-stent restenosis chronic total occlusion.

Percutaneous coronary intervention for in-stent restenosis (ISR) chronic total occlusion (CTO) has been a great challenge. There are occasions when the balloon is uncrossable or undilatable (BUs) even though the guidewire has passed, leading to failure of the procedure. Few studies have focused on the incidence, predictors, and management of BUs during ISR-CTO intervention. Patients with ISR-CTO were recruited consecutively between January 2017 and January 2022 and divided into two groups based on the presence of BUs. The clinical data of the two groups (BUs group and non-BUs group) were retrospectively analyzed and compared to explore the predictors and clinical management strategies of BUs. A total of 218 patients with ISR-CTO were included in this study, 23.9% (52/218) of whom had BUs. The percentage of ostial stents, stent length, CTO length, the presence of proximal cap ambiguity, moderate to severe calcification, moderate to severe tortuosity, and J-CTO score were higher in the BUs group than in the non-BUs group (p < 0.05). The technical success rate and the procedural success rate were lower in the BUs group than in the non-BUs group (p < 0.05). Multivariable logistic regression analysis showed that ostial stents (OR: 2.011, 95% CI: 1.112-3.921, p = 0.031), the presence of moderate to severe calcification (OR: 3.383, 95% CI: 1.628-5.921, p = 0.024) and moderate to severe tortuosity (OR: 4.816, 95% CI: 2.038-7.772, p = 0.033) were independent predictors of BUs. The initial rate of BUs in ISR-CTO was 23.9%. Ostial stents, presence of moderate to severe calcification, and moderate to severe tortuosity were independent predictors of BUs.

Success rate of endovascular recanalization for femoropopliteal artery total occlusion using the wingman catheter system.

Chronic total occlusion (CTO) in the femoropopliteal artery is challenging to treat. The Wingman catheter system is a novel device for CTO penetration with a nitinol/stainless steel beveled tip. There is a lack of real-world clinical data indicating the success rate. We evaluated the efficacy of the Wingman system. This was a single-center retrospective study. We enrolled 27 consecutives patients who underwent treatment for femoropopliteal CTO using the Wingman system in 2021. The primary outcome was success of CTO-crossing and secondary outcomes were success of the procedure, Wingman-related complications, and predictors for success of Wingman crossing. The mean age of the study population was 76years and the mean CTO length was 122mm. The success rate of Wingman crossing was 40.7% and the overall procedure success rate was 100%. Only one case of embolism and one of perforation associated with the Wingman procedure were seen; both were successfully recovered. Univariate analysis revealed in-stent occlusion and non-severe calcification to be factors associated with success (16.7% vs 0%, p = 0.012 and 12.5% vs 50.0%, p = 0.036, respectively). These real-world data of the Wingman system demonstrate it to be a safe and one of option for treating femoropopliteal CTO.

Preprocedural coronary computed tomography angiography in chronic total occlusion percutaneous coronary intervention: Insights from the PROGRESS-CTO registry

BackgroundPreprocedural coronary computed tomography angiography (CCTA) can be useful in procedural planning for chronic total occlusion (CTO) percutaneous coronary intervention (PCI). MethodsWe examined the clinical, angiographic and procedural characteristics and outcomes of cases with vs. without preprocedural CCTA in PROGRESS-CTO (NCT02061436). Multivariable logistic regression was used to adjust for confounding factors. ResultsOf 7034 CTO PCI cases, preprocedural CCTA was used in 375 (5.3%) with increasing frequency over time. Patients with preprocedural CCTA had a higher prevalence of prior coronary artery bypass graft surgery (39% vs. 27%, p < 0.001) and angiographically unfavorable characteristics including higher prevalence of proximal cap ambiguity (52% vs. 33%, p < 0.001) and moderate/severe calcification (59% vs. 41%, p < 0.001) compared with those without CCTA. CCTA helped resolve proximal cap ambiguity in 27%, identified significant calcium not seen on diagnostic angiography in 18%, changed estimated CTO length by >5 mm in 10%, and was performed as part of initial coronary artery disease work up in 19%. CCTA cases had higher J-CTO (2.6 ± 1.2 vs. 2.3 ± 1.3, p < 0.001) and PROGRESS-CTO (1.3 ± 1.0 vs. 1.2 ± 1.0 p = 0.027) scores. After adjusting for potential confounders, cases with preprocedural CCTA had similar technical success (odds ratio [OR]: 1.18, 95% confidence interval [CI], 0.83–1.67) and incidence of major adverse cardiovascular events (OR: 1.47, 95% CI, 0.72–3.00). ConclusionPreprocedural CCTA was used in ~5% of CTO PCI cases. While CCTA may help with procedural planning, especially in complex cases, technical success and MACE were similar with or without CCTA.

A novel initial wiring technique for chronic total occlusion of the superficial femoral artery using the structural features of a polymer jacket guidewire

BackgroundTo evaluate the efficacy of the GLadIus MG drilLINg technique (GLIMGLIN), a novel initial wiring technique using the Gladius MG™ structural features, for crossing the superficial femoral artery (SFA) with chronic total occlusion (CTO).MethodsThis retrospective, single-center study enrolled 27 symptomatic patients (mean age 77.4 ± 8.5 years; 20 men) with de novo SFA CTO (mean CTO length 16.1 ± 8.9 cm) who underwent GLIMGLIN as the initial wiring between January 2020 and December 2021. The success of GLIMGLIN was defined when the wire crossing was completed using a Gladius MG™ and a microcatheter without any additional devices and techniques.ResultsThe success rate of GLIMGLIN was 48.1%. Intravascular ultrasound findings showed complete true lumen passage in the GLIMGLIN success group. Compared to the failure group, the proximal (6.3 ± 0.8 vs. 5.5 ± 0.9 mm, p = 0.02) and distal (5.9 ± 0.5 vs. 5.4 ± 0.6 mm, p = 0.02) reference vessel diameters were significantly larger, and the rate of calcium angle > 180° was significantly lower (30.8 vs. 71.4%, p = 0.04) in the success group. No significant difference was shown in the CTO length between two groups. Total wiring time, total procedure time, and fluoroscopic time were significantly shorter in the success group.ConclusionsGLIMGLIN may enable operators to perform CTO wiring easily and efficiently in selected cases.

Comparative Analysis of Patient Characteristics in Chronic Total Occlusion Revascularization Studies: Trials vs Real-World Registries.

The few randomized controlled trials (RCTs) on chronic total occlusion (CTO) percutaneous coronary intervention (PCI) are subject to selection bias. The purpose of this study was to evaluate the differences between real-world CTO patients and those enrolled in RCTs. This study performed a meta-analysis of national and dedicated CTO PCI registries and compared patient characteristics and outcomes with those of RCTs that randomized patients to CTO PCI versus medical therapy. Given the large sample size differences between RCTs and registries, the study focused on the absolute numbers and their clinical significance. The study considered a 5% relative difference between groups to be potentially clinically relevant. From 2012 to 2022, 6 RCTs compared CTO PCI versus medical therapy (n=1,047) and were compared with 15 registries (5 national and 10 dedicated CTO PCI registries). Compared with registry patients, RCT patients had fewer comorbidities, including diabetes, hypertension, previous myocardial infarction, and prior coronary artery bypass graft surgery. RCT patients had shorter CTO length (29.6 ± 19.7mm vs 32.6 ± 23.0mm, a relative difference of 9.2%) and lower Japan-Chronic Total Occlusion Score scores (2.0 ± 1.1 vs 2.3 ± 1.2, a relative difference of 13%) compared with those enrolled in dedicated CTO registries. Procedural success was similar between RCTs (84.5%) and dedicated CTO registries (81.4%) but was lower in national registries (63.9%). There is a paucity of randomized data on CTO PCI outcomes (6 RCTs, n=1,047). These patients have lower risk profiles and less complex CTOs than those in real-world registries. Current evidence from RCTs may not be representative of real-world patients and should be interpreted within its limitation.

The Role of Multimodality Imaging for Percutaneous Coronary Intervention in Patients With Chronic Total Occlusions.

BackgroundPercutaneous coronary intervention (PCI) of Chronic total occlusions (CTOs) has been traditionally considered a challenging procedure, with a lower success rate and a higher incidence of complications compared to non-CTO-PCI. An accurate and comprehensive evaluation of potential candidates for CTO-PCI is of great importance. Indeed, assessment of myocardial viability, left ventricular function, individual risk profile and coronary lesion complexity as well as detection of inducible ischemia are key information that should be integrated for a shared treatment decision and interventional strategy planning. In this regard, multimodality imaging can provide combined data that can be very useful for the decision-making algorithm and for planning percutaneous CTO recanalization.AimsThe purpose of this article is to appraise the value and limitations of several non-invasive imaging tools to provide relevant information about the anatomical characteristics and functional impact of CTOs that may be useful for the pre-procedural assessment and follow-up of candidates for CTO-PCI. They include echocardiography, coronary computed tomography angiography (CCTA), nuclear imaging, and cardiac magnetic resonance (CMR). As an example, CCTA can accurately delineate CTO location and length, distal coronary bed, vessel tortuosity and calcifications that can predict PCI success, whereas stress CMR, nuclear imaging and stress-CT can provide functional evaluation in terms of myocardial ischemia and viability and perfusion defect extension.

Risk Factor Analysis for Crossing Failure in Primary Antegrade Wire-Catheter Approach for Femoropopliteal Chronic Total Occlusions

Introduction: Antegrade wire-catheter crossing remains the primary approach for femoropopliteal interventions. Nonetheless, data reporting on crossing failure are limited. Aim of this study is to identify risk factors for antegrade crossing failure in patients with femoropopliteal chronic total occlusions (CTOs). Methods: This is a single-center, retrospective analysis. Patients with femoropopliteal CTOs treated between May 2018 and February 2020 were included into this study. Primary endpoint of this analysis was primary crossing success defined as successful antegrade crossing without the use of retrograde access, crossing or re-entry devices. The assisted crossing success was additionally analyzed. A logistic regression analysis identified risk factors for failed primary antegrade crossing. Results: Data from 300 patients were analyzed. The majority (n=183, 61%) presented with lifestyle limiting claudication. The mean lesion length was 180 mm [interquartile range (IQR) 100–260 mm], whereas the median CTO length was 100 mm (IQR=50–210 mm). A chronic total occlusion crossing approach based on plaque morphology (CTOP) type I configuration was observed in 9% (n=26) of the lesions, type II in 61% (n=183), type III in 8% (n=25), and type IV in 66 CTOs (n= 66, 22%). Severe calcification based on the Peripheral Arterial Calcium Scoring Scale (PACSS), Peripheral Academic Research Consortium (PARC), and 360° grading systems was identified in 17%, 24%, and 28% of the lesions, respectively. A contralateral femoral access was used in 278 cases (93%). The primary crossing success amounted to 70% (n=210). The use of a re-entry device in 28 patients (9%) or of a combined antegrade–retrograde approach in 11% (n=34) of the cases increased the assisted crossing success to 89% (n=267). The presence of calcification (odds ratio [OR]=4.2, 95% CI=1.7–10.2) or of circumferential calcium (OR=2.5, 95% CI=1.3–4.9), a CTOP class ΙΙΙ or ΙV (OR=1.9, 95% CI=1.4–2.6), a proximal superficial femoral artery (SFA) occlusion (OR=3.5, 95% CI=1.7–7.4) and a CTO at P3 (OR=4.1, 95% CI=1.5–10.8) were associated with an increased risk for antegrade crossing failure. Conclusions: In this study, chronic total occlusions (CTO) morphology, calcification burden, and lesion’s location were identified as independent risk factors for failed antegrade crossing. Nonetheless, the use of alternative crossing strategies significantly increased the overall crossing success.

Safety and efficacy of dedicated guidewire, microcatheter, and guide catheter extension technologies for chronic total coronary occlusion revascularization: Primary results of the Teleflex Chronic Total Occlusion Study.

Description of procedural outcomes using contemporary techniques that apply specialized coronary guidewires, microcatheters, and guide catheter extensions designed for chronic total occlusion (CTO) percutaneous revascularization is limited. A prospective, multicenter, single-arm study was conducted to evaluate procedural and in-hospital outcomes among 150 patients undergoing attempted CTO revascularization utilizing specialized guidewires, microcatheters and guide extensions. The primary endpoint was defined as successful guidewire recanalization and absence of in-hospital cardiac death, myocardial infarction (MI), or repeat target lesion revascularization (major adverse cardiac events, MACE). The prevalence of diabetes was 32.7%; prior MI, 48.0%; and previous bypass surgery, 32.7%. Average (mean ± standard deviation) CTO length was 46.9 ± 20.5 mm, and mean J-CTO score was 1.9 ± 0.9. Combined radial and femoral arterial access was performed in 50.0% of cases. Device utilization included: support microcatheter, 100%; guide catheter extension, 64.0%; and mean number of study guidewires/procedure was 4.8 ± 2.6. Overall, procedural success was achieved in 75.3% of patients. The rate of successful guidewire recanalization was 94.7%, and in-hospital MACE was 19.3%. Achievement of TIMI grade 2 or 3 flow was observed in 93.3% of patients. Crossing strategies included antegrade (54.0%), retrograde (1.3%) and combined antegrade/retrograde techniques (44.7%). Clinically significant perforation resulting in hemodynamic instability and/or requiring intervention occurred in 16 (10.7%) patients. In a multicenter, prospective registration study, favorable procedural success was achieved despite high lesion complexity using antegrade and retrograde guidewire maneuvers and with acceptable safety, yet with comparably higher risk than conventional non-CTO PCI.

Impact of Guidewire Route on Severe Dissection After Balloon Angioplasty for Femoropopliteal Chronic Total Occlusion Lesions: An Intravascular Ultrasound Analysis

To determine the impact of the guidewire route on severe dissection after balloon angioplasty for femoropopliteal chronic total occlusion (CTO) lesions using a new intravascular ultrasound (IVUS) assessed classification scheme corresponding to a conventional angiographic classification scheme. Images for 21 femoropopliteal CTO lesions treated endovascularly between May 2018 and December 2019 were used for analysis. IVUS images after guidewire passage and those after balloon angioplasty were evaluated at 1 cm intervals. Cross sectional images were obtained (n = 219) and divided into two groups by the guidewire route: those in which the guidewire passed through the inner half of the luminal radius (central wiring group, 139 cross sectional images) and those in which the guidewire passed through the outer half of the luminal radius (eccentric wiring group, 80 cross sectional images). Angiographically severe dissection was defined as Type C or greater according to the National Heart, Lung, and Blood Institute classification, to which six dissection morphology patterns were applied based on IVUS images (Types A - E2). Central wiring was achieved in an average of 69.6 ± 28.0% of the CTO length from per limb analysis. Among the IVUS assessed dissection morphology patterns, Types D - E2 were more frequently correlated with angiographically severe dissection than were Types A - C (57.5% vs. 13.7%, p < .001). Multivariable analysis showed that soft plaque was a predictive factor for (odds ratio [OR] 2.14; 95% confidence interval [CI] 1.007 - 4.72; p= .048) and central wiring was a protective factor (OR 0.27; 95% CI 0.14 - 0.49; p < .001) against Type D - E2 dissection patterns assessed by IVUS after balloon angioplasty. Lesions with Type D - E2 dissection patterns assessed by IVUS were correlated with angiographically severe dissection. Central wiring may be useful for preventing severe dissection after balloon angioplasty for femoropopliteal CTO lesions.

Prediction of successful guidewire crossing of below-the-knee chronic total occlusions using a Japanese scoring system

ObjectiveTo develop a scoring system that can adequately predict a successful guidewire crossing (S-GC) of below-the-knee (BTK) chronic total occlusions (CTOs) in angiographic evaluation. MethodsA retrospective, multicenter, nonrandomized study examined 448 consecutive BTK CTOs in 299 patients treated with endovascular therapy in seven Japanese medical centers from April 2012 to April 2020. The cohort was classified into two groups: an S-GC group and a failed guidewire crossing group. ResultsThe final logistic regression model created by a backward stepwise multivariate logistic regression model included five variables: “No outflow of the target vessel,” “CTO length ≥200 mm,” “Reference vessel diameter <2.0 mm,” “Calcification at the proximal entry point,” and “Blunt type at entry point.” Optimisms were adjusted using 1000 bootstrap samples with replacement and candidate's risk score models developed according to optimism-adjusted correlation coefficients of risk factors. Choosing the best model as the Japanese-BTK (J-BTK) CTO score by comparing the optimism-adjusted area under receiver-operating characteristic curves it was decided to assign one point to “Blunt type at the proximal entry point,” one point to “Calcification at the proximal entry point,” one point to “Reference vessel diameter <2.0 mm,” one point to “CTO length ≥200 mm,” and two points to “No outflow of the target vessel.” This rule was then used to categorize BTK CTOs into four grades with varying probabilities of S-GC: grade A (J-BTK CTO score of 0 and 1), grade B (score of 2 and 3), grade C (score of 4 and 5), and grade D (score of 6). Rates of S-GC in each grade (grades A, B, C, and D) were 97.3%, 76.8%, 19.3%, and 0%, respectively. Lesions categorized as grade C or D have a lower chance of S-GC. Internal validation was performed using the Hosmer-Lemeshow test (P = .99). ConclusionsThe J-BTK CTO score predicts the probability of an S-GC of BTK CTOs and stratifies the difficulty of endovascular therapy for BTK CTOs in angiographic evaluation.

Identification of micro-channels within chronic total occlusions using contrast-enhanced ultrasound

BackgroundVascular micro-channels within chronic total occlusions (CTO) have been identified in histopathology and animal studies. They have been proposed as a potential path for achieving endovascular crossing via the lumen. There are currently no noninvasive means of imaging these structures. The aim of this study was to investigate whether contrast-enhanced ultrasound (CEUS) examination can identify micro-channels within CTO in humans. MethodsCTO within the femoropopliteal arteries were imaged with CEUS examination in 38 patients. Segments containing micro-channels were identified and their length measured. The proportion of occlusion length containing micro-channels was assessed for each case. Micro-channel appearances including linear or tortuous configuration, crossing of occlusion caps, and connections to vasa vasorum were recorded. ResultsThe median CTO length was 17.0 cm (interquartile range [IQR], 6.9-27.9 cm) and median age of CTO was 12 months (IQR, 6-16 months). Micro-channels were identified in 92.1% of cases (35/38). The median length within a lesion containing micro-channels was 6.4 cm (IQR, 2.4-14.3 cm) and median proportion of CTO containing micro-channels was 47.9% (IQR, 1.7%-28.5%). A linear micro-channel configuration was seen in 84.2% of cases and a tortuous configuration was seen in 57.9% of cases. Micro-channel connections through the cap were seen in 50% (19/38 cases) and connections to the vasa vasorum in 71.1% (27/38 cases). No association was found between the proportion of each lesion containing micro-channels and CTO age, lesion length or calcification severity. There were no adverse effects related to contrast use. ConclusionsCEUS can be used to detect micro-channels in CTO in human femoropopliteal arteries. This imaging technique is safe and minimally invasive and may represent a practical method for selection of occlusion crossing method. Further work is required to determine whether identification of micro-channels can be used to improve treatment decision-making and provide a better understanding of the natural history of femoropopliteal CTO.

A Novel Algorithm for Treating Chronic Total Coronary Artery Occlusion

BackgroundGuidewire manipulation time is rarely used in chronic total occlusion (CTO) percutaneous coronary intervention (PCI) strategies. ObjectivesThis study sought to develop an algorithm based on angiographic characteristics and guidewire manipulation time. MethodsThis study assessed 5,843 patients undergoing CTO PCI between January 2014 and December 2017 and enrolled in the Japanese CTO-PCI expert registry and analyzed their CTO-PCI strategies, procedural outcomes, and guidewire manipulation time. ResultsPrimary retrograde approach was performed on 1,562 patients. The average Japanese CTO score of primary antegrade approach and primary retrograde approach were 1.7 ± 1.1 and 2.3 ± 1.1, respectively (p < 0.001). The overall guidewire and technical success rates were 92.8% and 90.6%, respectively. Median guidewire manipulation time of guidewire success and failure were 56 min (interquartile range [IQR]: 22 to 111 min) and 176 min (IQR: 130 to 229 min), respectively. Median successful guidewire crossing time of single wiring and parallel wiring in the antegrade alone were 23 min (IQR: 11 to 44 min) and 60 min (IQR: 36 to 97 min), and rescue retrograde approach and primary retrograde approach were 126 min (IQR: 87 to 174 min) and 107 min (IQR: 70 to 161 min), respectively (p < 0.001). Significant predictors for antegrade guidewire failure in primary antegrade approach, which were reattempt, CTO length of ≥20 mm, and no stump, did not predict guidewire failure after collateral channel crossing in primary retrograde approach. ConclusionsResults from a large registry with information on guidewire manipulation time as well as CTO characteristics suggest a redefinition of the current strategy algorithms.

IVUS Assessment of the Crossing Pathway of an Intraluminal Reentry Device Used in the Primary Treatment of Infrainguinal Chronic Total Occlusions

Purpose: To examine with intravascular ultrasound (IVUS) the crossing pathways of the TruePath reentry device during primary antegrade recanalization of infrainguinal chronic total occlusions (CTOs). Methods: Between July 2017 and September 2018, a prospective multicenter study enrolled 143 consecutive patients (mean age 75±9 years; 101 men) with 146 CTOs treated in an antegrade approach using the TruePath reentry device with IVUS assessment of the crossing pathway in successful cases. Outcome measures were complete success (reentry device reached the distal true lumen), assisted success (reentry device use followed by a conventional guidewire to reach the distal true lumen), reentry device crossing route by IVUS assessment, and procedure- and device-related complications. Regression analyses were employed to identify any relevant associations between baseline patient variables and the outcome measures; results are presented as the odds ratio (ORs) and 95% confidence interval (CI). Results: Complete success was achieved in 82 (56.2%) lesions; any success (complete plus assisted) was documented in 117 (80.1%) lesions. Four (3%) perioperative device-related complications were observed. The crossing route was intraplaque for most of the total crossing distance in both complete success cases (95.3%±13.2%) and any success cases (94.8%±14.4%), with relatively short subintimal (3.6%±10.2% and 4.2%±11.2%, respectively) or intramedial (1.2%±5.8% and 1.0%±5.4%, respectively) crossing. CTO length was a significant risk factor for not achieving complete success (OR 1.74, 95% CI 1.13 to 2.68, p=0.012), and a history of failed revascularization was associated with not achieving any success (OR 6.40, 95% CI 1.28 to 28.9, p=0.038). Conclusion: The intraplaque route was the primary pathway taken by the TruePath reentry device as it crossed infrainguinal CTOs. Crossing rates were acceptable, with few device-related complications. However, a longer CTO length and a failed revascularization history negatively affected the success rate.

P5750Manipulation strategy for crossing coronary chronic total occlusion: an update from the Japanese CTO-PCI expert registry

Abstract Background The percutaneous coronary intervention (PCI) strategy for chronic total occlusion (CTO) based on the guidewire manipulation time remains infrequent. Purpose We aimed to assess CTO-PCI strategy on the basis of guidewire manipulation time. Methods A total of 5843 patients undergoing CTO PCI between January 2014 and December 2017 and enrolled in the Japanese CTO-PCI expert registry were assessed. Their CTO-PCI strategies, procedural outcomes, and guidewire manipulation time were analysed. Results The primary retrograde approach was performed on 1562 patients (26.7%). The overall guidewire and technical success rates were 92.8% and 90.6%, respectively. Median guidewire manipulation time of guidewire success and failure were 56 (interquatile range [IQR]: 22 to 111) min and 176 (IQR: 130 to 229) min, respectively. The average Japanese CTO score of the primary antegrade approach with the antegrade alone, the primary antegrade approach with the retrograde approach, and the primary retrograde approach were 1.7±1.1, 2.1±1.2, and 2.3±1.1, respectively (p&lt;0.001). Median successful guidewire crossing time of single wiring in the antegrade alone was 23 (IQR: 11 to 44) min, and that of the primary retrograde approach was significantly shorter than that of the primary antegrade approach with the retrograde approach (107 [IQR: 70 to 161] min vs. 126 [IQR: 87 to 174] min; p&lt;0.001). Reattempt, CTO length ≥20 mm, and proximal cap ambiguity were the predictors of guidewire failure in the primary antegrade approach with antegrade alone, but were not those in the primary retrograde approach. Conclusions Although successful guidewire crossing time of the primary antegrade approach with the antegrade alone is short, that of the primary retrograde approach can be shorter than that of the primary antegrade approach with the retrograde approach. Choosing an appropriate CTO-PCI strategy leads to shortening of successful guidewire crossing time.

Impact of Elevated Serum Uric Acid Level on Target Lesion Revascularization After Percutaneous Coronary Intervention for Chronic Total Occlusion

Elevated serum uric acid (SUA) level is reportedly associated with subsequent cardiovascular events including revascularization in patients with coronary artery disease. However, the impact of SUA level on revascularization in patients with chronic total occlusion (CTO), one of the highest risk subsets in coronary artery disease, is unclear. The aim of this study was to evaluate the impact of SUA level on target lesion revascularization (TLR) in contemporary percutaneous coronary intervention (PCI) for CTO. A total of 165 patients who underwent successful PCI with new-generation drug-eluting stent for CTO under intravascular ultrasound guidance were included. Patients were classified into 3 groups according to the tertiles of SUA level at baseline. Coronary angiography was qualitatively and quantitatively assessed, and gray-scale intravascular ultrasound was also analyzed. The primary end point was TLR. The tertiles of SUA level were as follows: low tertile, ≤5.2 mg/dl; intermediate tertile, 5.3 to 6.4 mg/dl; and high tertile, ≥6.5 mg/dl. During a median follow-up of 34 months, TLR was observed in 5 patients (8.8%) in the low tertile, in 5 (9.4%) in the intermediate tertile, and in 14 (25.5%) in the high tertile (p = 0.02). Kaplan-Meier analysis demonstrated a significantly higher incidence of TLR in patients with high tertile than the low and intermediate groups. Multivariable analysis showed SUA ≥6.5 mg/dl, diabetes mellitus, and longer CTO length as independent predictors of TLR. In conclusion, in patients who underwent PCI with drug-eluting stent, elevated SUA level was associated with TLR after successful recanalization of CTO.

Impact of recanalization of chronic total occlusion on left ventricular electrical remodeling

BackgroundSuccessful percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) is associated with reduction of cardiac mortality, as well as reducing fatal ventricular arrhythmias. The aim of this study was to evaluate the effect of recanalization of CTO on endocardial left ventricular voltages by paired electrophysiological studies.MethodsSixteen consecutive patients who underwent PCI for de novo CTO lesions were included. High‐density mapping was performed during sinus rhythm before and 8 months after PCI. According to the amplitude of bipolar electrograms, the left ventricular endocardium was classified into a preserved normal voltage (>1.5 mV), border zone (0.5–1.5 mV), and dense scar areas (<0.5 mV).ResultsThe border zone area had a significant positive correlation with CTO length, as well as a significant negative correlation observed in the preserved voltage region. In the successful PCI patient, the median dense scar area did not change significantly (reported as [median difference: 95% confidence interval]) between baseline and after PCI (0.1 cm2: –2.8 to 2.9). However, the area of the border zone decreased (–10.5 cm2: –16.8 to –4.1) and the preserved voltage area increased significantly (19.2 cm2: 7.7–30.6). In addition, successful PCI was related to slight, but significant, increase in the amplitude of unipolar and bipolar voltage (1.55 mV: 0.88–3.33, 0.23 mV: 0.08–0.36).ConclusionsRecanalization of CTO may promote reverse electrical remodeling in the border zone of the left ventricle, without affecting the dense scar tissue.

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 methodsThis 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. ResultsA 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).

HOW TO SELECT CORONARY WIRE FOR ANTEGRADE RECANALIZATION OF CHRONIC TOTAL OCCLUSIONS

Aim. To define principles of coronary wire choice during coronary artery chronic total occlusion (CTO) recanalization by antegrade approach. Material and methods. From 2009 to 2013 the attempt of coronary artery CTO recanalization by antegrade approach was undertaken for 217 patients. Depending on success of CTO crossing by coronary wire patients were divided into 2 groups: group 1 (n=164) - successful wire crossing, group 2 (n=53) -unsuccessful attempt of CTO recanalization by coronary wire.Results. In the group 2 there were more frequent CTO localization in the right coronary artery (p&lt;0,05 as compared to group 1), presence of blunt stump, higher frequency of side branches in the zone of proximal CTO cup, and large CTO length (p&lt;0,001 as compared to group 1). CTO recanalization in 47% cases begun from soft wire with polymeric coating and tapered tip, successful recanalization by these wire type was achieved in 49,02% patients. Using non-tapered tip intermediate stiffness wire as the first choice wire was associated with the failure of recanalization (p=0,0440 in intergroup comparison). At impossibility of CTO recanalization by soft wire with polymeric coating and tapered tip used as a first choice, it replacement on non-tapered tip intermediate stiffness wire allowed to achieve successful recanalization in 36,67% patients. In the cases of this strategy uneffectiveness using stiff wire with polymeric coating and tapered tip as a third choice allowed additionally to attain successful recanalization in 60% cases. Replacement of the soft wire with polymeric coating and tapered tip on stiff wire with polymeric coating and tapered tip, executable at presence of meaningful rigidity in the proximal CTO cup zone associated with the achievement the successful recanalization in 60% cases.Conclusion. On the basis of the obtained data it was created the conception of step-up wire stiffness increase during the CTO recanalization by antegrade approach.