Outcomes with retrograde versus antegrade chronic total occlusion revascularization

Antegrade approach versus retrograde approach percutaneous coronary intervention for chronic total occlusion: An updated meta-analysis

BACKGROUND

Retrograde approach has notably improved success rates of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). However, longer procedural time, increase use of fluoroscopy and contrast dye have been reported in retrograde techniques in CTO PCI. We aimed to study in-hospital and long-term outcomes of retrograde approach versus antegrade approach in CTO PCI.

METHODS

We searched PubMed, Scopus, WOS, and Cochrane Central until June 2023 to include all relevant studies that compared retrograde approach versus antegrade approach in patients with CTO PCI. We synthesized the outcome data using a random-effects model, expressing the effect estimates as odds ratios (OR) or mean difference (MD) with corresponding 95 % confidence intervals (CI).

RESULTS

A total of 18 studies comprising 21,276 patients were included in the analysis. Regarding in-hospital outcomes, antegrade approach was associated with lower odds of MACE (OR= 0.34, 95 % CI: 0.23 to 0.51), all-cause mortality (OR= 0.35, 95 % CI: 0.19 to 0.64), MI (OR= 0.36, 95 % CI: 0.25 to 0.53), urgent pericardiocentesis (OR= 0.27, 95 % CI: 0.16 to 0.46), CIN (OR= 0.46, 95 % CI: 0.33 to 0.65), procedural complications (OR= 0.52, 95 % CI: 0.33 to 0.83), target vessel perforation (OR= 0.45, 95 % CI: 0.32 to 0.64). while antegrade was associated with higher success rates (OR= 1.16, 95 % CI: 1.1 to 1.22).

CONCLUSION

Compared to antegrade technique, retrograde was associated with higher risk for in-hospital and long-term adverse events, and preferably should be performed in more complex CTO lesions.

Short- and long-term outcomes of antegrade versus retrograde approaches in patients undergoing percutaneous coronary intervention for chronic total occlusion: A meta-analysis

BACKGROUND

Chronic Total Occlusion (CTO) involves severe coronary artery blockage that impairs blood flow and affects 15-20 % of patients undergoing coronary angiography and over 40 % with diabetes or heart failure. Percutaneous Coronary Intervention (PCI) is used to restore blood flow in such cases. The retrograde approach, developed due to lower success with the antegrade method in complex cases, improves outcomes but increases complications. This meta-analysis compares the efficacy and safety of both approaches to guide clinical practice.

METHODS

A comprehensive literature search was conducted on PubMed, Embase, Google Scholar, and Scopus until June 5, 2024, to find studies comparing antegrade and retrograde approaches in CTO-PCI patients. Pooled risk ratios (RR) with 95 % confidence intervals (CI) were calculated using R software (version 4.4.1), with significance set at p < 0.05. Random-effects models were used for all analyses.

RESULTS

Our analysis included 22 observational studies with 49,152 CTO-PCI patients: 35,844 in the antegrade arm and 13,308 in the retrograde arm. The antegrade approach showed significantly lower risks of in-hospital outcomes, including mortality [RR: 0.45; p < 0.001], myocardial infarction [RR: 0.37; p < 0.001], major adverse cardiovascular events [RR: 0.34; p < 0.001], and cerebrovascular events [RR: 0.50; p = 0.011]. Long-term outcomes, such as all-cause mortality [RR: 0.71; p = 0.157] and myocardial infarction [RR: 0.76; p = 0.438], were comparable between both approaches.

CONCLUSION

The antegrade technique shows better outcomes and procedural advantages over retrograde revascularization, though long-term outcomes are similar. Further studies, especially randomized controlled trials are needed to confirm these findings.

Comparison of Clinical Outcomes Between Antegrade and Retrograde Techniques for Chronic Total Occlusion Revascularizations: A Systematic Review and Meta-Analysis

Chronic total occlusions (CTOs) present significant challenges in interventional cardiology. This meta-analysis aims to compare the efficacy and safety of retrograde versus antegrade techniques in CTO percutaneous coronary intervention (PCI). A systematic review and meta-analysis were conducted following PRISMA guidelines. Electronic databases were searched through June 20, 2024. Studies comparing outcomes between antegrade and retrograde methods for CTO-PCI were included. Primary outcomes were procedural and technical success. Secondary outcomes included major adverse cardiac events (MACE), all-cause mortality, and myocardial infarction. The final analysis included seventeen studies. The antegrade approach showed a 5% higher likelihood of technical success (OR: 1.05, 95% CI: 1.02-1.09) and 14% higher odds of procedural success (OR: 1.14, 95% CI: 1.10-1.19) compared to the retrograde approach. The antegrade group also demonstrated lower risks of MACE, all-cause mortality, and myocardial infarction (RR: 0.40, 95% CI: 0.26-0.63). This meta-analysis suggests that the antegrade approach in CTO-PCI is associated with higher success rates and lower risks of adverse outcomes compared to the retrograde approach. However, the retrograde technique remains crucial for complex lesions and patients with multiple comorbidities.

Effects of a prior failed attempt on the outcomes of subsequent chronic total occlusion-percutaneous coronary intervention

Objectives

Patients undergoing a prior failed attempt of chronic total occlusion-percutaneous coronary intervention (CTO-PCI) represent a challenging subgroup across all patients undergoing CTO-PCI. There are limited data on the effects of a prior failed attempt on the outcomes of subsequent CTO-PCI. We aimed to compare the procedural results and 24-month outcomes of prior-failed-attempt CTO-PCI with those of initial-attempt CTO-PCI.

Methods

Patients who underwent attempted CTO-PCI between January 2017 and December 2019 were prospectively enrolled. We analyzed the procedural results and 24-month major adverse cardiac events (MACE) between patients who underwent prior-failed-attempt and initial-attempt CTO-PCI. MACE was defined as a composite of cardiac death, target vessel-related myocardial infarction, and ischemia-driven target vessel revascularization (TVR) during follow-up.

Results

In total, 484 patients who underwent CTO-PCI (prior-failed-attempt, n = 49; initial-attempt, n = 435) were enrolled during the study period. After propensity score matching (1:3), 147 patients were included in the initial-attempt group. The proportion of the Japanese-CTO (J-CTO) score ≥2 was higher in the patients who underwent prior failed attempt than in those who underwent initial attempt (77.5% vs. 38.8%, p < 0.001). The retrograde approach was more often adopted in the prior-failed-attempt group than in the initial-attempt group (32.7% vs. 3.4%,  [P< 0.001). Successful CTO revascularization rates were significantly lower in the prior-failed attempt-group than in the initial attempt group (53.1% vs. 83.3%, P < 0.001). The multivariate analysis revealed that J-CTO score ≥2 [odds ratio (OR), 0.359; 95% confidence interval (CI), 0.159-0.812; P = 0.014], intravascular ultrasound procedure (OR, 4.640; 95% CI, 1.380-15.603; P = 0.013), and prior failed attempt (OR, 0.285; 95% CI, 0.125-0.648; P = 0.003) were the independent predictors for successful CTO revascularization. There were no significant differences in major procedural complications (2.0% vs. 0.7%, p = 0.438) and MACE rates (4.1% vs. 8.8%, p = 0.438) between the groups, mainly due to the TVR rate (4.1% vs. 8.2%, P = 0.522).

Conclusions

Compared with initial-attempt CTO-PCI, prior-failed-attempt CTO-PCI deserves more attention, since it is associated with a lower successful CTO revascularization rate. Prior failed attempt, J-CTO score ≥2, and IVUS procedure are the determining factors for predicting successful CTO revascularization. There are no significantly different unfavorable outcomes between patients who undergo prior-failed-attempt and initial-attempt CTO-PCI.

Impact of successful antegrade and retrograde CTO PCI on short-term prognosis

BACKGROUND

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) carries risk of complications and should be attempted when the anticipated benefits exceed the potential risks. The primary indication for CTO-PCI is symptom improvement. However, the impact of CTO-PCI on angina and subsequent incidence of major adverse cardiovascular event (MACE) rate remains controversial. Our aim was to study the impact of technically successful elective CTO-PCI on the procedural success rate and short-term MACE. The current study was a prospective cohort study that included a total of 80 patients who were referred to our center (Ain Shams University Hospitals) for elective CTO-PCI and underwent technically successful CTO-PCI. Data were collected on patient arrival to our department, and then, the patients were observed during hospital admission to record any In-Hospital MACE. These patients were then followed up for 6 months to record improvement or worsening of their symptoms and to assess occurrence of any MACE including hospitalization and undergoing symptom-driven coronary angiography.

RESULTS

The mean age of our patients was 56 ± 9.6 years, and 73 patients (91%) were men. Sixty-two patients (77.5%) were done via an antegrade approach, and 18 patients (22.5%) were done via a retrograde approach with an overall procedural success rate of 91.25% (antegrade 93.5%, retrograde 83.3%). The overall mean procedure time was 102 min, the mean contrast volume used was 371 ml, and the mean cumulative air kerma dose was 7.2 Gy. The retrograde group required longer procedure times, larger volumes of contrast and higher exposure to radiation. The overall in-hospital MACE was 8.75%. Sixty-five patients in our study (81.25%) showed an improvement in the grade of their exertional dyspnea or angina within the 6-month follow-up period. Thirteen patients in our study (16.25%) needed re-hospitalization within a 6-month period after PCI. The overall target lesion revascularization rate at 6 months was 8.75%.

CONCLUSIONS

Technically successful CTO PCI in a well-equipped center with highly qualified CTO operators resulted in high procedural success rates and low incidence of short-term MACE.

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.

The role of intravascular imaging in chronic total occlusion percutaneous coronary intervention

Chronic total occlusions (CTOs) represent the most complex subset of coronary artery disease and therefore careful planning of CTO percutaneous coronary recanalization (PCI) strategy is of paramount importance aiming to achieve procedural success, and improve patient's safety and post CTO PCI outcomes. Intravascular imaging has an essential role in facilitating CTO PCΙ. First, intravascular ultrasound (IVUS), due to its higher penetration depth compared to optical coherence tomography (OCT), and the additional capacity of real-time imaging without need for contrast injection is considered the preferred imaging modality for CTO PCI. Secondly, IVUS can be used to resolve proximal cap ambiguity, facilitate wire re-entry when dissection and re-entry strategies are applied and most importantly to guide stent deployment and optimization post implantation. The role of OCT during CTO PCI is currently limited to stent sizing and optimization, however, due to its high spatial resolution, OCT is ideal for detecting stent edge dissections and strut malapposition. In this review, we describe the use of intravascular imaging for lesion crossing, plaque characterization and wire tracking, extra- or intra-plaque, and stent sizing and optimization during CTO PCI and summarize the findings of the major studies in this field.

Antegrade versus Retrograde Approach for Recanalization of Ostial or Stumpless Coronary Chronic Total Occlusion

Purpose

This research aimed to evaluate the procedural and in-hospital clinical outcomes of percutaneous coronary intervention (PCI) for ostial or stumpless chronic total occlusion (CTO) utilizing both the antegrade-only and retrograde approaches.

Methods

A comprehensive retrospective examination was conducted on the procedural and in-hospital clinical outcomes of 89 consecutive patients subjected to ostial or stumpless CTO PCI at our institution between April 2015 and October 2022.

Results

The antegrade-only technique demonstrated a superior technical success rate (92.0% vs 71.9%, p = 0.041) and procedural success rate (92.0% vs 68.8%, p = 0.022) in comparison to the retrograde approach (RA). The RA group presented a notably elevated Japanese-CTO (J-CTO) score relative to the antegrade-only approach group (2.45±0.73 vs 1.64±0.70, p < 0.001). The antegrade-only approach group manifested an increased frequency of microchannels at the proximal stump relative to the RA group (56.0% vs 10.9%, p < 0.001). In-hospital major adverse cardiac events (MACE) and in-hospital myocardial infarction (MI) were observed more prevalently in the RA group (18.8% vs 0, p = 0.003; 15.6% vs 0, p = 0.008; respectively). A J-CTO score below 2 and the manifestation of microchannels at the proximal stump were identified as predictors for successful antegrade-only approach PCI for ostial or stumpless CTO (OR: 2.79 [95% CI: 1.92-5.03, P =0.003]; OR: 2.89 [95% CI: 1.32-6.03, P =0.001]; respectively).

Conclusion

Relative to RA PCI for ostial or stumpless CTO, the antegrade-only approach is utilized for less complex CTO lesions and is associated with a diminished probability of in-hospital MACE.

Efficiency of the Guide Extension Catheter-Facilitated Tip-in Technique in the Recanalization of Coronary Chronic Total Occlusion

Background

The tip-in technique, which involves advancing an antegrade microcatheter cross the lesion over a retrograde guidewire, is an elaborated maneuver in the recanalization of coronary chronic total occlusion (CTO). We seek to assess the efficiency of a guide extension catheter-facilitated tip-in technique in comparison to the traditional retrograde approach, which is accomplished by an externalization wire.

Methods

Thirty-three CTO patients successfully revascularized using guide extension catheter-facilitated "tip-in" were included and matched with another 33 patients by J-CTO score and operators, whose CTO was recanalized using an externalized wire. The manipulation time from the first retrograde wire entering the antegrade guide to the first antegrade balloon inflation in the occlusion was calculated.

Results

Compared with the wire-externalization group, the manipulation time in the tip-in group was significantly shortened [389s; interquartile range (IQR), 272-478 vs 706s; IQR, 560-914; p < 0.001]. There was a trend in decreasing total operation time and radiation dose, but it did not reach statistical significance.

Conclusion

Guide extension catheter-facilitated tip-in is an efficient method to achieve the recanalization of CTO in a retrograde way, which would be pivotal when the retrograde microcatheter could not be advanced into the antegrade guide catheter.

Complex Retrograde Chronic Occlusion Percutaneous Coronary Intervention via a Gastroepiploic Artery Graft

Surgical bypass grafts are commonly used retrograde conduits to facilitate chronic total occlusion (CTO) percutaneous coronary intervention (PCI). While extensive experience exists using saphenous vein grafts as retrograde conduits in CTO PCI, information on the utilization of arterial grafts is more limited. In particular, the gastroepiploic artery (GEA) is a very uncommonly used arterial graft in contemporary bypass surgery and its role for retrograde CTO recanalization has received little study. We describe a case of right coronary artery CTO that was recanalized using the retrograde approach via a GEA graft to the posterior descending artery and highlight the specific challenges of this approach.

Impact of minimum contrast media volumes during percutaneous coronary intervention for chronic total occlusion lesion

Contrast media exposure is associated with contrast-induced nephropathy (CIN) following percutaneous coronary intervention (PCI) of chronic total occlusion (CTO). Aim of this study is to assess the utility of minimum contrast media volume (CMV ≤ 50 mL) during CTO-PCI for CIN prevention in patients with chronic kidney disease (CKD). We extracted data from the Japanese CTO-PCI expert registry; 2863 patients with CKD who underwent CTO-PCI performed from 2014 to 2020 were divided into two groups: minimum CMV (n = 191) and non-minimum CMV groups (n = 2672). CIN was defined as an increased serum creatinine level of ≥ 25% and/or ≥ 0.5 mg/dL compared with baseline levels within 72 h of the procedure. In the minimum CMV group, the CIN incidence was lower than that in the non-minimum CMV group (1.0% vs. 4.1%; p = 0.03). Patient success rate was higher and complication rate was lower in the minimum CMV group than in the non-minimum CMV group (96.8% vs. 90.3%; p = 0.02 and 3.1% vs. 7.1%; p = 0.03). In the minimum CMV group, the primary retrograde approach was more frequent in the case of J-CTO = 1,2 and 3-5 groups compared to that in non-minimum CMV-PCI group (J-CTO = 0; 11% vs. 17.7%, p = 0.06; J-CTO = 1; 22% vs. 35.8%, p = 0.01; J-CTO = 2; 32.4% vs. 46.5%, p = 0.01; and J-CTO = 3-5; 44.7% vs. 80.0%, p = 0.02). Minimum CMV-PCI for CTO in CKD patients could reduce the incidence of CIN. The primary retrograde approach was observed to a greater extent in the minimum CMV group, especially in cases of difficult CTO.

Percutaneous Coronary Intervention for Chronic Total Occlusion-Contemporary Approach and Future Directions

In the aging society, the issue of coronary chronic total occlusion (CTO) has become a challenge for invasive cardiologists. Despite the lack of clear indications in European and American guidelines, the rates of percutaneous coronary interventions (PCI) for CTO increased over the last years. Well-conducted randomized clinical trials (RCT) and large observational studies brought significant and substantial progress in many CTO blind spots. However, the results regarding the rationale behind revascularization and the long-term benefit of CTO are inconclusive. Knowing the uncertainties regarding PCI CTO, our work sought to sum up and provide a comprehensive review of the latest evidence on percutaneous recanalization of coronary artery chronic total occlusion.

Anemia and periprocedural complications determine contrast-associated acute kidney injury after recanalization of chronic coronary occlusions in chronic kidney disease

BACKGROUND

Contrast-associated acute kidney injury (CA-AKI) is a potential risk associated with the percutaneous coronary interventions (PCI) for chronic total coronary occlusions (CTO) particularly with pre-existing chronic kidney disease (CKD). The determinants of CA-AKI in patients with pre-existing CKD in an era of advanced strategies of CTO recanalization techniques need to be considered for a risk evaluation of the procedure.

METHODS

A consecutive cohort of 2504 recanalization procedures for a CTO between 2013 and 2022 was analyzed. Of these, 514 (20.5%) were done in patients with CKD (estimated glomerular filtration rate < 60 ml/min based on the most recently used CKD Epidemiology Collaboration equation).

RESULTS

The rate of patients classified to have CKD would be lower with 14.2% using the Cockcroft-Gault equation, and 18.1% using the modified Modification of Diet in Renal Disease equation. The technical success was high with 94.9% and 96.8% (p = 0.04) between patients with and without CKD. The incidence of CA-AKI was 9.9% versus 4.3% (p < 0.001). The major determinants of CA-AKI in patients with CKD were the presence of diabetes and a reduced ejection fraction, as well as periprocedural blood loss, whereas a higher baseline hemoglobin and the use of the radial approach prevented CA-AKI.

CONCLUSIONS

In patients with CKD CTO PCI could be performed successfully at a higher cost of CA-AKI. Correcting preprocedural anemia and avoiding intraprocedural blood loss may reduce the incidence of CA-AKI.

Prognostic implication of lipidomics in patients with coronary total occlusion undergoing PCI

BACKGROUND

Predictors of prognosis in patients with coronary chronic total occlusion (CTO) undergoing elective percutaneous coronary intervention (PCI) have remained lacking. Lipidomic profiling enables researchers to associate lipid species with disease progression and may improve the prediction of cardiovascular events.

METHODS

In the present study, 781 lipids were measured by targeted lipidomic profiling in 350 individuals (50 healthy controls, 50 patients with coronary artery disease and 250 patients with CTO). L1-regularized logistic regression was used to identify lipid species associated with adverse cardiovascular events and create predicting models, which were verified by 10-fold cross-validation (200 repeats). Comparisons were made between a traditional model constructed with clinical characteristics alone and a combined model built with both lipidomic data and traditional factors.

RESULTS

Twenty-four lipid species were dysregulated exclusively in patients with CTO, most of which belonged to sphingomyelin (SM) and triacylglycerol (TAG). Compared with traditional risk factors, new model combining lipids and traditional factors had significantly improved performance in predicting adverse cardiovascular events in CTO patients after PCI (area under the curve, 0.870 vs. 0.726, p < .05; Akaike information criterion, 129 versus 156; net reclassification improvement, 0.312, p < .001; integrated discrimination improvement, 0.244, p < .001). Nomogram was built based on the incorporated model and proved efficient by Kaplan-Meier method.

CONCLUSIONS

Lipidomic profiling revealed lipid species which may participate in the formation of CTO and could contribute to the risk stratification in CTO patients undergoing PCI.

Extraplaque versus intraplaque tracking in chronic total occlusion percutaneous coronary intervention

OBJECTIVE

To compare the clinical outcomes after extraplaque (EP) versus intraplaque (IP) tracking in chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

BACKGROUND

The impact of modern dissection and reentry (DR) techniques on the long-term outcomes of CTO PCI remains controversial.

METHODS

We performed a systematic review and meta-analysis of studies that compared EP versus IP tracking in CTO PCI. Odds ratios (ORs) with 95% confidence intervals (CIs) are calculated using the Der-Simonian and Laird random-effects method.

RESULTS

Our meta-analysis included seven observational studies with 2982 patients. Patients who underwent EP tracking had significantly more complex CTOs with higher J-CTO score, longer lesion length, and more severe calcification and had significantly longer stented segments. During a median follow-up of 12 months (range 9-12 months), EP tracking was associated with a higher risk of major adverse cardiovascular events (MACE) (OR 1.50, 95% CI (1.10-2.06), p = 0.01) and target vessel revascularization (TVR) (OR 1.69, 95% CI (1.15-2.48), p = 0.01) compared with IP tracking. There was no difference in the incidence of all-cause death (OR 1.37, 95% CI (0.67-2.78), p = 0.39), myocardial infarction (MI) (OR 1.48, 95% CI (0.82-2.69), p = 0.20), stent thrombosis (OR 2.09, 95% CI (0.69-6.33), p = 0.19), or cardiac death (OR 1.10, 95% CI (0.39-3.15), p = 0.85) between IP and EP tracking.

CONCLUSION

EP tracking is utilized in more complex CTOs and requires more stents. EP tracking is associated with a higher risk of MACE, driven by a higher risk of TVR at 1 year, but without an increased risk of death or MI compared with IP tracking. EP tracking is critically important for contemporary CTO PCI.

One 6-F Guiding Catheter and One Microcatheter to Accomplish a Retrograde Chronic Total Occlusion Approach: The “Reverse Tip-In” or “Introspect” Technique

The retrograde approach has significantly increased the overall success rate of chronic total occlusion (CTO) percutaneous coronary intervention (PCI), up to 90% in the hands of experienced CTO operators. The “tip-in” technique involves inserting an antegrade microcatheter over the retrograde guidewire, allowing for antegrade intervention on the CTO segment. Through the presentation of the following case, we want to illustrate how to undertake a retrograde approach to bridge the occluded segment via the “reverse tip-in” or “introspect” technique, using a single guiding catheter with one microcatheter inside.

Predictors of success in primary retrograde strategy in chronic total occlusion percutaneous coronary intervention: insights from the PROGRESS-chronic total occlusion registry

BACKGROUND

An upfront (primary) retrograde strategy is often used in complex chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

METHODS

We examined the clinical, angiographic characteristics, and procedural outcomes of CTO PCIs that were approached with a primary retrograde strategy in the Prospective Global Registry for the Study of CTO Intervention (PROGRESS-CTO, NCT02061436).

RESULTS

Of 10,286 CTO PCIs performed between 2012 and 2022, a primary retrograde strategy was used in 1329 (13%) with an initial technical success of 66%, and a final success of 83%. Patients who underwent successful versus unsuccessful primary retrograde cases had similar characteristics: age (65 ± 10 vs. 65 ± 9, years, p = 0.203), men (83% vs. 87%, p = 0.066), prior PCI (71% vs. 71%, p = 0.809), and prior coronary artery bypass graft surgery (52% vs. 53%, p = 0.682). The PROGRESS-CTO score (1.3 ± 0.9 vs. 1.6 ± 0.9, p < 0.001), air kerma radiation (3.9 ± 2.8 vs. 3.4 ± 2.6, gray, p = 0.013), and contrast use (294 ± 148 ml vs. 248 ± 128, ml, p < 0.001) were higher in the unsuccessful group, whereas the presence of interventional collaterals (95% vs. 72%, p < 0.001) and Werner collateral connection grade 2 (43% vs. 31%, p < 0.001) were higher in the successful group. On multivariable logistic regression analysis, the only variable associated with a successful primary retrograde strategy was the presence of interventional collaterals: odds ratio: 6.52 (95% confidence intervals; 3.5-12.1, p < 0.001).

CONCLUSION

Presence of interventional collaterals is independently associated with higher success rates with a primary retrograde strategy in CTO PCI.

Update on chronic total occlusion percutaneous coronary intervention

Chronic total occlusion (CTO) percutaneous coronary interventions (PCI) can be challenging to perform. The main indication for CTO PCI is to improve symptoms. Several contemporary studies have reported high CTO PCI success rates at experienced centers but success rates in all-comer registries remain low. Several scores can estimate the difficulty and the likelihood of success of CTO PCI. Dual arterial access and use of CTO crossing algorithms can improve the success and safety of CTO PCI. Intracoronary imaging can optimize stent expansion and minimize adverse cardiovascular events. While complications are more common in CTO PCI, careful planning and prompt diagnosis and treatment can prevent them or minimize their adverse consequences. In this article, we review contemporary data on the indications, safety and efficacy of CTO PCI.

Primary versus rescue retrograde approach for chronic total coronary occlusion

OBJECTIVES

We aimed to assess the advantages of using the retrograde approach as an initial strategy rather than as a rescue strategy for complex chronic total occlusions (CTOs).

BACKGROUND

Even for complex CTOs where a retrograde approach is deemed necessary, an antegrade approach is frequently used as an initial strategy in real-world practice.

METHODS

We evaluated 352 retrograde procedures for CTO conducted at our high-volume center between January 2007 and January 2019. Procedural efficiency and safety was assessed based on the guidewire manipulation time (GWMT) and the occurrence of procedure-related adverse events for the primary retrograde approach (PRA) and the rescue retrograde approach (RRA).

RESULTS

PRA and RRA were used in 191 (54.3%) and 161 (45.7%) of the CTO procedures, respectively. The complexity of the CTO lesion was significantly higher in the PRA group than in the RRA group (Japanese-CTO score, 2.62 ± 1.07 vs. 2.38 ± 1.06, p = 0.037). The technical success rate of two groups was similar (p = 0.47). The median GWMT required for PRA was significantly shorter than that for RRA (85 [interquartile range, 55-126] vs. 120 [85-157] min, p < 0.001). The total duration of the procedure and fluoroscopic time were shorter, and the number of guidewires and amount of contrast used during the index procedure were smaller in the PRA group. The incidence of procedure-related adverse events was not significantly different between the two groups.

CONCLUSIONS

PRA showed higher procedural efficiency than RRA with comparable safety. Opting for PRA for complex CTOs might be a rational decision to enhance the procedural efficiency.

Procedural Results and Long-Term Outcomes of Percutaneous Coronary Intervention for in-Stent Restenosis Chronic Total Occlusion Compared with de novo Chronic Total Occlusion

Background

In-stent restenosis (ISR) chronic total occlusion (CTO) represents a challenging subgroup for revascularization of CTO by percutaneous coronary intervention (PCI). There are limited data on the treatment and outcomes of PCI for ISR CTO.

Objective

We aimed to evaluate the procedural results and 2-year outcomes of PCI for ISR CTO compared with de novo CTO.

Methods

Patients undergoing attempted CTO PCI between January 2017 and December 2019 were prospectively enrolled. We analyzed the procedural results and 2-year major adverse cardiac events (MACE) in patients undergoing ISR CTO and those undergoing de novo CTO PCI.

Results

A total of 426 patients undergoing 484 consecutive CTO PCI (ISR CTO PCI, n=84; de novo CTO, n=400) were enrolled during the study period. Patients undergoing de novo CTO PCI had a significantly greater syntax score than those undergoing ISR CTO PCI [23.0 (17.5, 30.5) vs 21.5 (14.5, 27.0), p=0.039]. Technical (73.8% vs 79.0%, p=0.296) and procedural (73.8% vs 78.0, p=0.405) success rates, as well as the incidence of major procedural complications (1.2% vs 2.3%, p=0.842), were comparable between the two groups. After a median follow-up of 20 months, patients who underwent ISR CTO PCI had a significantly higher incidence of MACE (33.3% vs 10.3%, p<0.001), mainly attributed to the higher TVR rates (24.7% vs 7.6%, p<0.001). ISR CTO was the only independent predictor of MACE (hazard ratio, 4.124; 95% confidence interval, 1.951–8.717; p<0.001) during follow-up in patients who underwent CTO PCI.

Conclusion

ISR CTO PCI shows comparable technical and procedural success, as well as major procedural complications compared with de novo CTO PCI. However, patients who underwent ISR CTO PCI had a significantly worse prognosis than those who underwent de novo CTO PCI, in terms of MACE, driven by TVR. ISR CTO was the only independent predictor of MACE during the follow-up.

Anesthetic Considerations for Percutaneous Coronary Intervention for Chronic Total Occlusions-A Narrative Review

Advancing stent technology has enabled interventional cardiologists to perform percutaneous coronary intervention (PCI) to open chronic total occlusions (CTOs). Because PCI for CTOs improve patient anginal symptoms and quality of life, these procedures have been increasing over the past decade. Compared to standard PCI, these procedures are technically more difficult, with prolonged procedure time and increased risk of complications. Accordingly, anesthesiologists are increasingly being asked to provide sedation for these patients in the cardiac catheterization suite. In CTO PCI, anesthesiologists are more likely to encounter complications such as coronary artery perforation, malignant arrhythmias, non-target vessel ischemia, bleeding and shock. Additionally, CTO PCI may be supported by mechanical circulatory support devices. Understanding the procedural techniques of these complex PCI procedures is important to enable optimal anesthetic care in these patients. This narrative review discusses the pathophysiology, risks, benefits, procedural steps, and main anesthetic considerations for patients undergoing CTO PCI. Despite a growing body of literature, future research is still required to elucidate optimal anesthetic and mechanical support strategies in patients undergoing CTO PCI.

Complications during chronic total occlusion percutaneous coronary intervention: a sign- and symptom-based approach to early diagnosis and treatment

Coronary chronic total occlusions (CTO) are frequently found in patients undergoing coronary angiography. Despite their high prevalence and indication for revascularization in a relevant proportion of cases, CTO recanalization is attempted only in a minority of cases. This is due to higher risk of procedural complications compared to non-CTO interventions and because the CTO-PCIs are the most complex procedures in interventional cardiology. In particular, the perceived higher risk of complications during CTO intervention might discourage new operators from engaging in this challenging field. The aim of this work is to review the potential complications of CTO percutaneous coronary intervention, and to provide an algorithmic, sign- and symptom-based approach to facilitate early recognition and effective management.

Antegrade versus retrograde techniques for Chronic Total Occlusions (CTO): a review and comparison of techniques and outcomes

Introduction: As the field of chronic total occlusion percutaneous coronary intervention has evolved, technical approaches have evolved and been refined.Areas covered: In this review, we discuss the major techniques utilized in modern CTO PCI including antegrade wiring, antegrade dissection reentry, retrograde wiring, and retrograde dissection reentry. Retrograde techniques have been extensively studied in comparison to antegrade techniques. Retrograde techniques have contributed to increases in CTO PCI success rates and are generally used in higher complexity lesions. Observational data ssuggestincreased sshort-termcomplications in procedures requiring the use of retrograde techniques; however, llong-termCTO PCI durability and patient outcomes have been shown to be similar among procedures using antegrade only versus retrograde techniques.Expert opinion: Retrograde techniques play a vital role in the technical success of CTO PCI, particularly among more complex lesions and in patients with high burdens of comorbidities. Increases in procedural safety with equipment iteration and in the use of adjunctive imaging will play an important role in the selection of appropriate retrograde conduits and the overall success rates of CTO PCI.

Current challenges and prevention strategies for chronic total occlusion (CTO) complications

Introduction: Percutaneous coronary intervention (PCI) of chronic total occlusion (CTO) can be challenging, but high success rates (85-90%) are currently achieved at experienced centers with approximately 3% risk for a major periprocedural complication.Areas covered: CTO PCI complications can be categorized according to location such as cardiac and non-cardiac (vascular access complications, thromboembolic complications, contrast-related and radiation injury) complications. Cardiac complications are further subdivided into coronary (acute closure, perforation, and equipment loss or entrapment) and non-coronary (hypotension, myocardial infarction, tamponade, arrhythmias).Expert opinion: In this article, we review strategies to prevent and treat CTO PCI complications. Careful monitoring throughout the case enables prevention and early detection of a complication. If a complication occurs, rapid implementation of treatment using an algorithmic approach can minimize its adverse impact.

The Canadian Contribution to Science, Techniques, Technology, and Education in Chronic Total Occlusion Percutaneous Coronary Intervention

Chronic total occlusions are considered the most complex coronary lesions in interventional cardiology. This article reviews the Canadian clinical and academic contributions to this field, including innovative procedural techniques, teaching and proctoring, clinical research, and the development of novel tools and therapies.

When antegrade microcatheter does not follow: The "facilitated tip-in technique"

The introduction of retrograde techniques in percutaneous coronary intervention (PCI) of chronic total occlusion (CTO) has significantly improved the success rates. After crossing the CTO lesion in the retrograde approach, wire externalization is a pivotal step to complete the PCI. Many techniques have been described to accomplish externalization in different scenarios of increasing difficulty. We describe the novel "facilitated tip-in technique" which involves the insertion of the back end of an extra-guidewire into and through the antegrade microcatheter (MC) in order to increase antegrade support and overcome demanding CTO cases where, even after successful tip-in technique, the antegrade MC does not cross the CTO segment.

Retrograde Approach to Chronic Total Occlusion Percutaneous Coronary Intervention

The retrograde approach has increased the success rate of chronic total occlusion percutaneous coronary intervention but has also been associated with a higher risk of complications. The retrograde approach is usually performed in complex lesions, in which the antegrade approach is not feasible or has failed previously. Using a systematic 10-step approach can maximize the likelihood of success and minimize the risks of retrograde chronic total occlusion interventions.