Applicability of J-CTO channel score to predict microcatheter tracking during retrograde percutaneous coronary intervention of chronic total occlusions: Insights from the SURFING MICRO registry.

BACKGROUND: The J-chronic total occlusion (CTO) channel score can predict guidewire tracking of the collateral channels (CCs), but its efficacy in predicting microcatheter tracking has never been tested in the setting of retrograde CTO-percutaneous coronary intervention (PCI). AIMS: Predicting microcatheter collateral tracking during retrograde CTO-PCIs. METHODS: A total of 189 patients undergoing retrograde CTO-PCI from April 2017 to August 2021 were screened. The primary outcome of interest was a correlation between J-CTO channel score and microcatheter tracking failure (MTF) after successful CC tracking by the guidewire. The independent association between anatomical features of the J-CTO channel score and the primary outcome of interest was explored. RESULTS: After adjustment, only small size (adjusted OR: 12.70, 95% confidence interval [CI]: 1.79-89.82; p = 0.01) and continuous bends (adjusted OR: 14.15, 95% CI: 2.77-72.34; p < 0.001) remained significantly associated with an increased risk of MTF for septal collaterals. The small size was the only predictor of the MTF for epicardial collaterals (OR: 6.39, 95% CI: 1.13-35.96; p = 0.020) at univariate analysis. Patients in the MTF group had a lower incidence of procedural success compared with patients in the microcatheter tracking success (MTS) group (40.0% vs. 93.9%, p < 0.001) and had a higher incidence of collateral perforations (20.0% vs. 3.0%, p < 0.001). CONCLUSION: Small and tortuous septal collaterals, identified by a score ≥3, are associated with an increased risk of MTF, lower incidence of procedural success, and higher risk of procedural complications driven by collateral perforations.

Intravascular ultrasound-guided STAR 2.0: A new technique for chronic total occlusion recanalization.

The use of the subintimal space has allowed a massive advancement in the field of chronic total occlusion percutaneous coronary intervention (PCI). The STAR technique is the first of subintimal techniques. Despite a high acute success rate, follow-up results showed unfavorable outcomes with half of the treated patients showing restenosis/reocclusion at 6 months. We present three cases in which a modification of the STAR technique guided by intravascular ultrasound (IVUS), namely the STAR 2.0, was used as a bailout for successful PCI of chronic total occlusions.

Management of iatrogenic ascending aortic dissection after percutaneous intervention of chronic total occlusion.

BACKGROUND: This study highlights the prevalence and conservative management strategies of iatrogenic ascending aortic dissection after percutaneous intervention (PCI) of chronic total occlusion (CTO). METHODS: Retrospective analysis on patients who underwent CTO PCI from one medical center from 2020 to 2022 was performed by two operators. Data was obtained from the Prospective Global Registry for the Study of CTO database. RESULTS: Out of 318 patients, there were six reported cases of iatrogenic ascending aortic dissection. The causes of dissection included guiding catheter trauma, antegrade injection, two retrograde injection, and two cases of balloon rupture after lithotripsy. IVUS-guided stenting of the coronary back to the origin to seal the entry of the dissection flap occurred in two patients. All patients had a conservative management approach. No patient had to undergo urgent surgery. CONCLUSION: While the incidence remains rare, complications, including aortic dissection, are more frequent in CTO PCI as compared to non-CTO PCI. IVUS can be used to complete coronary intervention so long as the patient remains clinically and hemodynamically stable. Patients should have formal imaging with either transesophageal echocardiogram or computed tomography angiography. The outcomes of patients who experience iatrogenic aortic dissection during CTO PCI with stable coronary disease seem to be better than in patients with acute coronary syndrome.

Electrocautery-assisted re-entry to resolve bilateral aorto-ostial chronic total occlusions due to leaflet obstruction following transcatheter aortic valve replacement.

Coronary artery obstruction is a rare but life-threatening complication of transcatheter aortic valve replacement (TAVR). While urgent percutaneous coronary intervention has been described in cases of acute occlusion, little is known about the interventional management of obstruction once it has occurred in the chronic setting. We describe a case in which electrocautery-assisted re-entry was successfully utilized to manage the right coronary artery and left main chronic total occlusion due to leaflet-induced coronary artery obstruction after TAVR.

Stingray CART (K14 technique): A novel antegrade dissection reentry strategy.

A novel device based CART technique (K14 technique) has been described with 2 case examples to illustrate the same. This CART has been performed after ADR and Reverse-CART were unsuccessful.

Coils embolization use for coronary procedures: Basics, indications, and techniques.

The use of coils is fundamental in interventional cardiology and can be lifesaving in selected settings. Coils are classified by their materials into bare metal, fiber coated, and hydrogel coated, or by the deliverability method into, pushable or detachable coils. Coils are delivered through microcatheters and the choice of coil size is important to ensure compatibility with the inner diameter of the delivery catheter, firstly to be able to deliver and secondly to prevent the coil from being stuck and damaged. Clinically, coils are used in either acute or in elective setting. The most important acute indication is typically the sealing coronary perforation. In the elective settings, coils can be used for the treatment of certain congenital cardiac abnormalities, aneurysms, fistulas or in the treatment of arterial side branch steal syndrome after CABG. Coils must always be delivered under fluoroscopy guidance. There are some associated complications with coils that can be acute or chronic, that nictitates regular followed-up. There is a need for education, training and regular workshops with hands-on to build the experience to use coils in situations that are infrequently encountered.

Outcomes of contemporary versus conventional reverse controlled and antegrade and retrograde subintimal tracking in chronic total occlusion revascularization.

BACKGROUND: Chronic total occlusion (CTO) lesions remain technically challenging for percutaneous coronary intervention (PCI). The introduction of a retrograde approach has allowed marked improvement in the success rate of CTO recanalization. Reverse controlled anterograde and retrograde sub-intimal tracking (reverse CART) is the predominant retrograde wire crossing technique and can be broadly classified into three categories: (1) conventional (2) contemporary and (3) extended. The present study aimed to compare the safety and efficacy of conventional and contemporary reverse CART techniques. METHODS: From March 2015 to May 2020, 303 patients achieving successful retrograde guidewire crossing with conventional or contemporary reverse CART during CTO PCI were included in the study. The patient characteristics, procedural outcomes and in-hospital and 1-year clinical events were compared between the conventional and contemporary groups. RESULTS: The distributions of the baseline and angiographic characteristics were similar in both study arms, except the CTO lesions of the conventional group were more complex, as reflected by borderline significantly higher mean J-CTO scores (3.4 ± 0.7 vs. 3.3 ± 0.8; p = 0.059). Recanalization using contemporary reverse CART was associated with a short procedure time (189.8 ± 44.4 vs. 181.7 ± 37.3 min; p = 0.044) and decreased procedural complications, particularly target vessel perforation (3.6% vs. 0.6%; p = 0.063) and major side-branch occlusion (36.7% vs. 28.0%; p = 0.051). Technical and procedural success and the in-hospital and 1-year outcomes were not significantly different between the groups. CONCLUSIONS: Contemporary reverse CART is associated with favorably high efficiency and low-complication rates and carries a comparable success rate and 1-year clinical outcomes as conventional reverse CART.

Collagenase to facilitate guidewire crossing in chronic total occlusion PCI-The Total Occlusion Study in Coronary Arteries-5 (TOSCA-5) trial.

BACKGROUND: Chronic total occlusions (CTO) are common and are associated with lower percutaneous coronary intervention (PCI) success rates, often due to failure of antegrade guidewire crossing. Local, intralesional delivery of collagenase (MZ-004) may facilitate guidewire crossing in CTO. AIMS: To evaluate the effect of MZ-004 in facilitating antegrade wire crossing in CTO angioplasty. METHODS: A total of 76 patients undergoing CTO PCI were enrolled at 13 international sites: 38 in the randomized training stage (collagenase [MZ-004] 900 or 1200 µg) and 38 in the placebo-controlled stage (MZ-004 900 or 1200 µg or placebo). Patients received the MZ-004 or identical volume saline (placebo group) in a double-blind design, injected via microcatheter directly into the proximal cap of the CTO. The following day patients underwent CTO PCI using antegrade wire techniques only. RESULTS: Patients were generally similar except for a trend for higher Japanese chronic total occlusion (J-CTO) score in the MZ-004 group (MZ-004 J-CTO score 1.9 vs. 1.4, p = 0.07). There was a numerical increase in the rates of guidewire crossing in the MZ-004 groups compared to placebo (74% vs. 63%, p = 0.52). Guidewire crossing with a soft-tip guidewire (≤1.5 g tip load) was significantly higher in the MZ-004 groups (0% in placebo, 17% in 900 µg, and 29% in 1200 µg MZ-004 group, p = 0.03). Rates of the major adverse cardiovascular event were similar between groups. CONCLUSION: Local delivery of MZ-004 into coronary CTOs appears safe and may facilitate CTO crossing, particularly with softer tipped guidewires. These data support the development of a pivotal trial to further evaluate this agent.

Minimalistic hybrid approach for the percutaneous treatment of chronic coronary total occlusions: An in-depth analysis of the whole algorithm.

INTRODUCTION: The minimalistic hybrid approach (MHA) is an algorithm to perform chronic total occlusion (CTO) percutaneous coronary intervention (PCI). The current study aims to evaluate the distribution of patients among the five different treatment strategies, the different techniques used in each strategy, the overall procedural success, and the safety of the MHA algorithm. METHODS: Data from a consecutive series of patients with a CTO who underwent elective PCI between February 2019 and July 2021 were prospectively collected and retrospectively analyzed. RESULTS: One hundred and forty-three CTOPCI in 135 patients were approached according to the MHA algorithm: 134 CTO (93.7%) were successfully recanalized and 9 procedures failed. About half of the procedures (48.3%) were approached using strategy A: antegrade "blind wiring" with contralateral retrograde options, making this the most popular strategy. A total of 89 procedures (62.2%) were completed with a single guiding catheter; in 86 (96.6%) a forearm approach was used. The remaining 54 cases were performed with dual access; in the majority of these patients (90.7%), a bilateral forearm approach was used. The only reason to use the femoral access was inadequate forearm access. One hundred and fifty-four out of 197 (78.2%) access sites were 6 French sheaths. CONCLUSION: MHA is a stepwise approach focused on the forearm approach to reduce the number of access sites and catheter size used in CTOPCI while maintaining proficiency and safety. Operators should be warned that this approach should be adopted only by experienced CTO operators who master all the strategies of the classic hybrid algorithm and the forearm approach.

Grade 3 coronary artery perforations in chronic total occlusion-percutaneous coronary intervention: Mechanisms, locations, and outcomes from the G3CAP Registry.

AIM: The impact of Grade III coronary perforations (G3-CP) in the setting of CTO-PCI is not well assessed. METHODS AND RESULTS: We reviewed 7773 CTO-PCI and 98,819 non CTO-PCI performed in 10 European centers: G3 perforation occurred in 87 patients (1.1%) during CTO PCI and 224 patients (0.22%) during non CTO-PCI (p < 0.001). G3-CP involved the CTO segment in 68% of patients and the retrograde channels in 14% of cases. In the CTO PCI group, wire induced G3-CP (50.5% vs. 32.5%, p = 0.02) occurred predominantly when dedicated CTO tapered and highly penetrative wires were used. Intra-procedural and in-hospital death rates were 4.6% vs. 5.8% and 3.6% vs. 7.5% respectively for CTO PCI and non-CTO PCI groups (p = NS). At a median follow up of 24 months, the overall mortality and MAE were respectively 7.8% and MAE 19% without difference among groups. CONCLUSIONS: We showed similar in-hospital and long-term outcomes when G3 perforations occurred during CTO PCI and non CTO-PCI.

Impact of prior coronary artery bypass grafting in patients undergoing chronic total occlusion-percutaneous coronary intervention: Procedural and clinical outcomes from the REgistry of Crossboss and Hybrid procedures in FrAnce, the NetheRlands, BelGium, and UnitEd Kingdom (RECHARGE).

AIM: Chronic total occlusions (CTO) in patients with history of coronary artery bypass graft (CABG) show more advanced and complex atherosclerotic pathology. Aim of our study is to compare outcomes in patients undergoing CTO percutaneous coronary intervention (PCI) with previous CABG versus those without in the REgistry of Crossboss and Hybrid procedures in FrAnce the NetheRlands, BelGium and UnitEd Kingdom (RECHARGE). METHODS & RESULTS: The RECHARGE cohort (1,252 patients) was divided in two groups according to the presence of previous CABG (217) or not. We also focused, in the post-CABG group, on a comparison between CTO in previously grafted vessels versus non-grafted vessels. The CTO complexity scores were higher and the success rate (71.9% vs. 88.7%, p < .001) was lower in the CABG group, this difference was driven by higher failure rates in high-complexity-score CTO. The rate of in-hospital complications was similar. In the post-CABG group, the procedural success of CTO located in previously grafted vessels versus those in vessels not previously grafted, was comparably suboptimal (73.1% vs. 68%, p = .47). CONCLUSION: Patients undergoing CTO PCI with prior CABG have a higher prevalence of comorbidities and more complex lesion characteristics. In the post-CABG population the success rate was significantly lower, particularly in high CTO complexity scores, though complication rates were comparable. In the post-CABG population, the CTO success rate was independent of the presence of a previous graft on the CTO vessel.

The "double stingray technique" for recanalizing chronic total occlusions with bifurcation at the distal cap.

Antegrade dissection re-entry is often discouraged for chronic total occlusions (CTOs) with a bifurcation at the distal cap due to risk of side branch occlusion that can lead to periprocedural myocardial infarction and incomplete revascularization. Antegrade dissection re-entry, however, is often needed, especially in complex cases. We present the novel "double Stingray technique" for CTOs involving bifurcations, in which the Stingray system is used twice for re-entry into both vessel branches, followed by two-stent bifurcation stenting to maintain the patency of both branches.

Incidence, predictors and longer-term impact of troponin elevation following hybrid chronic total occlusion percutaneous coronary intervention.

OBJECTIVES: We examined the incidence of periprocedural cardiac enzyme rise (PCER) [troponin T (TnT) or high-sensivity (hs)TnT >5× the upper limit of normal (ULN)] and periprocedural myocardial infarction (PMI), predictors of PCER and impact of PCER on the longer-term major adverse cardiac events (MACE) following hybrid chronic total occlusion (CTO) percutaneous coronary intervention (PCI). BACKGROUND: PCER and PMI after CTO PCI, risk factors for PCER and its impact on longer-term MACE are not fully understood. METHODS: Among 469 CTO PCI cases performed between 01/2010 and 12/2015, next-day TnT or hsTnT was measured in 455 (97%). We examined the incidence of PCER and PMI (with clinical context or TnT ≥70× ULN). In 269 successful cases who had TnT measured, longer-term MACE (death, MI or target-vessel revascularisation/re-occlusion) were assessed. RESULTS: Overall, 420 CTOs (92.3%) were treated successfully. PCER was documented in 34%, while PMI in 2.9%. By multivariable analyses, higher J-CTO score (OR = 1.3 per point; P = 0.002), lower creatinine clearance (OR = 1.01 per each cc/min decrease; P < 0.0001) and recent MI (OR = 2.4; P = 0.007) were independent pre-PCI risk factors for PCER. Among procedural variables, retrograde approach (OR = 1.9; P = 0.014) and procedure duration (OR = 1.2 per 30 min; P = 0.007) were associated with PCER. At a median follow-up of 396 days following successful CTO PCI, PCER was not associated with higher MACE (9.3% vs. 8.1%; P = 0.60), and was not a predictor of MACE in multivariable analysis. CONCLUSIONS: PCER following hybrid CTO PCI is detected in 1/3 of patients. However, true PMI occurs in 2.9%. PCER does not predict adverse long-term outcomes.

Antegrade fenestration and re-entry: The legacy continues.

Subintimal guidewire entry during antegrade wiring attempts can be approached with various techniques, such as: (a) withdraw and redirect the guidewire; (b) parallel wire technique; (c) re-entry using the Stingray system or guidewires; or (d) using the retrograde approach Antegrade fenestration and re-entry is a creative novel technique for antegrade re-entry that uses balloon angioplasty at the distal cap to create fenestrations between the false lumen and the distal true lumen, followed by advancement of a soft-polymer jacketed guidewire through the fenestrations to achieve distal true lumen re-entry Antegrade fenestration and re-entry is an intuitive, simple, and low-cost technique, but balloon inflation may cause subintimal hematoma that could hinder re-entry. Additional study is needed to refine how antegrade fenestration and re-entry should optimally be performed and to better understand its strengths and shortcomings.

Use of intravascular ultrasound for optimal vessel sizing in chronic total occlusion percutaneous coronary intervention.

Aim: The aim of this study is to provide evidence on how use of standardized intravascular ultrasound (IVUS) use impacts stent size choice in the setting of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) compared to visual estimation. Methods and results: Data of 82 consecutive patients who had successfully undergone IVUS-guided revascularization of CTO at the University Medical Center Mainz were analyzed. Angiography-based stent size prediction for the proximal and distal vessels was compared to the implanted stent diameter after IVUS assessment. Angiography-based stent size prediction for the proximal vessel was 3.09 ± 0.41, whereas IVUS use demonstrated larger vessel diameter, resulting in larger implanted stent diameter (3.24 ± 0.45, p < 0.001). Proximal vessel stent size prediction was underestimated in the majority of patients by angiographic estimation. Angiography-based stent size prediction for the distal vessel was 2.79 ± 0.38, whereas IVUS use demonstrated larger vessel diameter, resulting in larger implanted stent diameter (2.92 ± 0.39, p < 0.001). Conclusion: Pre-stent IVUS assessment in CTO PCI provides important information on vessel morphology and size. Angiography-based stent size prediction for the proximal and distal vessels was frequently underestimated, IVUS use demonstrated larger vessel diameter, resulting in significantly larger implanted stent diameter.

Comparison of long-term clinical outcomes of percutaneous coronary intervention for chronic total occlusion between patients with and without diabetes mellitus: a single-center retrospective observational study.

BACKGROUND: The prognosis of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) between patients with diabetes mellitus (DM) and those without DM is unknown. This study aimed to investigate whether DM has adverse effects on CTO PCI patients. METHODS: This single-center retrospective study included consecutive patients who underwent PCI for CTO at the China-Japan Friendship Hospital (Beijing, China) between January 2016 and April 2019. The clinical outcomes during follow-up were compared between patients with DM and those without DM. RESULTS: The analysis included 187 patients (152 males) aged 62.6±11.5 years. A total of 99 participants (52.9%) had DM, which involved a higher body mass index (BMI) and triglyceride level than those without DM (P<0.05). Participants with DM and those without DM had similar PCI success rates (89.9% vs. 95.4%, respectively) and complete revascularization rates (82.8% vs. 84.1%, respectively). There were no significant differences between groups in the rates of all-cause mortality, cardiac death, major adverse cardiovascular events (MACEs), readmission, recurrence of angina, target vessel revascularization (TVR), or myocardial infarction (MI) during a median follow-up of 20.5 months. Multivariable logistic regression revealed that CTO in a coronary branch vessel was associated with higher odds of all-cause death (odds ratio (OR): 53.56; 95% confidence interval (CI): 2.48 to 1,155.41; P<0.05) and failure of PCI for CTO (OR: 5.40; 95% CI: 1.263 to 23.098; P<0.05). Additionally, PCI for single CTO was associated with lower odds of MACEs (OR: 0.300; 95% CI: 0.118 to 0.765; P<0.05). CONCLUSIONS: The performance of PCI for CTO has a high success rate in both patients with DM and those without DM, and clinical outcomes are comparable between groups.