Validation of the BCIS CHIP Score in chronic total occlusion percutaneous coronary intervention.

BACKGROUND: The complex high-risk indicated percutaneous coronary intervention (CHIP) score is a tool developed using the British Cardiovascular Intervention Society (BCIS) database to define CHIP cases and predict in-hospital major adverse cardiac or cerebrovascular events (MACCE). AIM: To assess the validity of the CHIP score in chronic total occlusion (CTO) percutaneous coronary intervention (PCI). METHODS: We evaluated the performance of the CHIP score on 8341 CTO PCIs from the Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS-CTO) performed at 44 centers between 2012 and 2023. RESULTS: In our cohort, 7.8% (n = 647) of patients had a CHIP score of 0, 50.2% (n = 4192) had a CHIP score of 1-2, 26.2% (n = 2187) had a CHIP score of 3-4, 11.7% (n = 972) had a CHIP score of 5-6, 3.3% (n = 276) had a CHIP score of 7-8, and 0.8% (n = 67) had a CHIP score of 9+. The incidence of MACCE for a CHIP score of 0 was 0.6%, reaching as high as 8.7% for a CHIP score of 9+, confirming that a higher CHIP score is associated with a higher risk of MACCE. The estimated increase in the risk of MACCE per one score unit increase was 100% (95% confidence interval [CI]: 65%-141%). The AUC of the CHIP score model for predicting MACCE in our cohort was 0.63 (95% CI: 0.58-0.67). There was a positive correlation between the CHIP score and the PROGRESS-CTO MACE score (Spearman's correlation: 0.37; 95% CI: 0.35-0.39; p < 0.001). CONCLUSIONS: The CHIP score has modest predictive capacity for MACCE in CTO PCI.

Chronic total occlusion percutaneous coronary intervention of anomalous coronary arteries: insights from the PROGRESS CTO registry.

BACKGROUND: There is limited information about the frequency and outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) in anomalous coronary arteries (ACA). METHODS: We examined the clinical and angiographic characteristics and procedural outcomes of CTO PCI in ACA among 14,173 patients who underwent 14,470 CTO PCIs at 46 US and non-US centers between 2012 and 2023. RESULTS: Of 14,470 CTO PCIs, 36 (0.24%) were CTO PCIs in an ACA. ACA patients had similar baseline characteristics as those without an ACA. The type of ACA in which the CTO lesion was found were as follows: anomalous origin of the right coronary artery (ARCA) (17, 48.5%), anomalous origin of left circumflex coronary artery (9, 25.7%), left anterior descending artery and left circumflex artery with separate origins (4, 11.4%), anomalous origin of the left anterior descending artery (2, 5.7%), dual left anterior descending artery (2, 5.7%) and woven coronary artery 1 (2.8%). The Japan CTO score was similar between both groups (2.17 ± 1.32 vs 2.38 ± 1.26, p = 0.30). The target CTO in ACA patients was more likely to have moderate/severe tortuosity (44% vs 28%, p = 0.035), required more often use of retrograde approach (27% vs 12%, p = 0.028), and was associated with longer procedure (142.5 min vs 112.00 min [74.0, 164.0], p = 0.028) and fluoroscopy (56 min [40, 79 ml] vs 42 min [25, 67], p = 0.014) time and higher contrast volume (260 ml [190, 450] vs 200 ml [150, 300], p = 0.004) but had similar procedural (91.4% vs 85.6%, p = 0.46) and technical (91.4% vs 87.0%, p = 0.59) success. No major adverse cardiac events (MACE) were seen in ACA patients (0% [0] vs 1.9% [281] in non-ACA patients, p = 1.00). Two coronary perforations were reported in ACA CTO PCI (p = 0.7 vs. non-ACA CTO PCI). CONCLUSIONS: CTO PCI of ACA comprise 0.24% of all CTO PCIs performed in the PROGRESS CTO registry and was associated with higher procedural complexity but similar technical and procedural success rates and similar MACE compared with non-ACA CTO PCI.

International survey of chronic total occlusion percutaneous coronary intervention operators.

BACKGROUND: Contemporary chronic total occlusion (CTO) percutaneous coronary intervention (PCI) practice has received limited study. AIM: To examine the contemporary CTO PCI practice. METHODS: We performed an online, anonymous, international survey of CTO PCI operators. RESULTS: Five hundred forty-five CTO PCI operators and 190 interventional cardiology fellows with an interest in CTO PCI participated in this survey. Almost half were from the United States (41%), most (93%) were men, and the median h/week spent in the hospital was 58. Median annual case numbers were 205 (150-328) for PCIs and 20 (5-50) for CTO PCIs. Almost one-fifth (17%) entered CTO cases into registries, such as PROGRESS-CTO (55%) and EuroCTO (20%). More than one-third worked at academic institutions (39%), 31% trained dedicated CTO fellows, and 22% proctored CTO PCI. One-third (34%) had dedicated CTO PCI days. Most (51%) never discharged CTO patients the same day, while 17% discharged CTO patients the same day >50% of the time. After successful guidewire crossing, 38% used intravascular imaging >90% of the time. Most used CTO scores including J-CTO (81%), PROGRESS-CTO (35%), and PROGRESS-CTO complications scores (30%). Coronary artery perforation was encountered within the last month by 19%. On a scale of 0-10, the median comfort levels in treating coronary artery perforation were: covered stents 8.8 (7.0-10), coil embolization 5.0 (2.1-8.5), and fat embolization 3.7 (0.6-7.3). Most (51%) participants had a complication cart/kit and 25% conducted regular complication drills with catheterization laboratory staff. CONCLUSION: Contemporary CTO PCI practices vary widely. Further research on barriers to following the guiding principles of CTO PCI may improve patient outcomes.

Impact of preprocedural anemia on in-hospital and follow-up outcomes of chronic total occlusion percutaneous coronary intervention.

BACKGROUND: The impact of preprocedural anemia on the outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has received limited study. METHODS: We examined the clinical and angiographic characteristics and procedural outcomes of 8633 CTO PCIs performed at 39 US and non-US centers between 2012 and 2023. Anemia was defined as a hemoglobin level of <13 g/dL in men and <12 g/dL in women. RESULTS: Anemia was present in 1652 (19%) patients undergoing CTO PCI. Anemic patients had a higher incidence of comorbidities, such as diabetes mellitus, hypertension, dyslipidemia, heart failure, cerebrovascular disease, and peripheral arterial disease. CTOs in anemic patients were more likely to have complex angiographic characteristics, including smaller diameter, longer length, moderate to severe calcification, and moderate to severe proximal tortuosity. Anemic patients required longer procedure (119 vs. 107 min; p < 0.001) and fluoroscopy (45 vs. 40 min; p < 0.001) times but received similar contrast volumes. Technical success was similar between the two groups. In-hospital major adverse cardiac events (MACE) rates were higher in patients with anemia; however, this association was no longer significant after adjusting for confounding factors. Baseline anemia was independently associated with follow-up MACE (adjusted hazard ratio [HR]: 1.63; 95% confidence interval [CI]: 1.07-2.49; p = 0.023) and all-cause mortality (adjusted HR: 3.03; 95% CI: 1.41-6.49; p = 0.004). CONCLUSIONS: Preprocedural anemia is associated with more comorbidities, higher lesion complexity, longer procedure times, and higher follow-up MACE and mortality after CTO PCI.

Balloon-assisted subintimal entry (BASE) in chronic total occlusion percutaneous coronary interventions.

BACKGROUND: There is limited data on the use of the balloon-assisted subintimal entry (BASE) technique in chronic total occlusion (CTO) percutaneous coronary intervention (PCI). METHODS: We analyzed the baseline clinical and angiographic characteristics and outcomes of 155 CTO PCIs that utilized the BASE technique at 31 US and non-US centers between 2016 and 2023. RESULTS: The BASE technique was used in 155 (7.9%) of 1968 antegrade dissection and re-entry (ADR) cases performed during the study period. The mean age was 66 ± 10 years, 88.9% of the patients were men, and the prevalence of diabetes (44.6%), hypertension (90.5%), and dyslipidemia (88.7%) was high. Compared with 1813 ADR cases that did not use BASE, the target vessel of the BASE cases was more commonly the RCA and less commonly the LAD. Lesions requiring BASE had longer occlusion length (42 ± 23 vs. 37 ± 23 mm, p = 0.011), higher Japanese CTO (J-CTO) (3.4 ± 1.0 vs. 3.0 ± 1.1, p < 0.001) and PROGRESS-CTO (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention chronic total occlusion) (1.8 ± 1.0 vs. 1.5 ± 1.0, p = 0.008) scores, and were more likely to have proximal cap ambiguity, side branch at the proximal cap, blunt/no stump, moderate to severe calcification, and proximal tortuosity. Technical (71.6% vs. 75.5%, p = 0.334) and procedural success (71.6% vs. 72.8%, p = 0.821), as well as major adverse cardiac events (MACE) (1.3% vs. 4.1%, p = 0.124), were similar in ADR cases that used BASE and those that did not. CONCLUSIONS: The BASE technique is used in CTOs with longer occlusion length, higher J-CTO score, and more complex angiographic characteristics, and is associated with moderate success but also low MACE.

Impact of proximal cap ambiguity on the procedural techniques and outcomes of chronic total occlusion percutaneous coronary intervention: Insights from the PROGRESS-CTO Registry.

BACKGROUND: Proximal cap ambiguity is a key parameter in the global chronic total occlusion (CTO) percutaneous coronary intervention (PCI) crossing algorithm. METHODS: We examined the baseline characteristics and procedural outcomes of 9718 CTO PCIs performed in 9498 patients at 41 US and non-US centers between 2012 and 2022. RESULTS: Proximal cap ambiguity was present in 35% of CTO lesions. Patients whose lesions had proximal cap ambiguity were more likely to have had prior coronary artery bypass graft surgery (37% vs. 24%; p < 0.001). Lesions with proximal cap ambiguity were more complex with higher J-CTO score (3.1 ± 1.0 vs. 2.0 ± 1.2; p < 0.001) and lower technical (79% vs. 90%; p < 0.001) and procedural (77% vs. 89%; p < 0.001) success rates compared with nonambiguous CTO lesions. The incidence of major adverse cardiovascular events (MACE) was higher in cases with proximal cap ambiguity (2.5% vs. 1.7%; p < 0.001). The retrograde approach was more commonly used among cases with ambiguous proximal cap (50% vs. 21%; p < 0.001) and was more likely to be the final successful crossing strategy (29% vs. 13%; p < 0.001). The antegrade dissection and re-entry (ADR) "move-the-cap" techniques were also more common among cases with proximal cap ambiguity. CONCLUSIONS: Proximal cap ambiguity in CTO lesions is associated with higher utilization of the retrograde approach and ADR, lower technical and procedural success rates, and higher incidence of in-hospital MACE.

Aortocoronary dissection during percutaneous coronary interventions for chronic total occlusion: Insights from the PROGRESS-CTO registry.

BACKGROUND: Aortocoronary dissection is a potentially serious complication of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). METHODS: We examined the incidence, mechanisms, treatment, and outcomes of aortocoronary dissection among 12,117 CTO PCIs performed between 2012 and 2022 in a large multicenter CTO PCI registry. RESULTS: The incidence of aortocoronary dissection was 0.2% (n = 27). Most aortocoronary dissections occurred in the right coronary artery (96.3%, n = 26). The baseline clinical characteristics of patients with and without aortocoronary dissection were similar, except for dyslipidemia, which was less common in patients with aortocoronary dissection (70.4% vs. 86.0%; p = 0.019). The retrograde approach was used more commonly among cases complicated by aortocoronary dissection (59.3% vs. 31.0%; p = 0.002). Technical (74.1% vs. 86.6%; p = 0.049) and procedural (70.4% vs. 85.2%; p = 0.031) success rates were lower among aortocoronary dissection cases, with a similar incidence of in-hospital major adverse cardiovascular events (3.7% vs. 2.0%; p = 0.541). Of the 27 patients with aortocoronary dissection, 19 (70.4%) were treated with ostial stenting and 8 (29.6%) were treated conservatively without subsequent adverse clinical outcomes. No patients required emergency surgery. Follow-up was available for 22 patients (81.5%): during a mean follow up of 767 (±562) days, the incidence of in-stent restenosis was 11.1% (n = 3). CONCLUSIONS: Aortocoronary dissection occurred in 0.2% of CTO PCIs performed by experienced operators, was associated with lower technical and procedural success, and was treated most commonly with ostial stenting. None of the patients required emergency cardiac surgery.

Incidence, mechanisms, treatment, and outcomes of donor vessel injury during percutaneous coronary interventions for chronic total occlusion.

BACKGROUND: Donor vessel injury is a potentially life-threatening complication of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). AIMS: Our goal was to examine the incidence, mechanisms, treatment, and outcomes of patients with donor vessel injury in a large multicenter CTO PCI registry. METHODS: We analyzed the baseline clinical and angiographic characteristics, and procedural outcomes of 12,349 CTO PCIs performed between 2012 and 2022 at 44 centers. RESULTS: The incidence of donor vessel injury was 0.35% (n = 43). The baseline clinical characteristics of patients with and without donor vessel injury were similar. Cases complicated by donor vessel injury were more complex with higher Japanese CTO score (2.9 ± 1.1 vs. 2.4 ± 1.3; p = 0.004) and lower procedural success rate (69.8% vs. 85.2%; p = 0.004). The retrograde approach was used more commonly in donor vessel injury cases (68.9% vs. 30.9%; p < 0.001). Most (53.5%) donor vessel injuries were guide catheter-induced, whereas 20.9% were due to donor vessel thrombosis. Of the 43 patients with donor vessel injury, 36 (83.7%) were treated with stenting and seven (16.3%) received a left ventricular assist device. The incidence of major adverse cardiovascular events (MACEs) was significantly higher in cases with donor vessel injury (23.3% vs. 2.0%; p < 0.001). Of the 43 patients with donor vessel injury, five patients (11.6%) experienced acute myocardial infarction and four patients (9.3%) died. CONCLUSIONS: Donor vessel injury, occurred in 0.35% of CTO PCIs performed by experienced operators, was mainly due to guide catheter-induced dissection or thrombosis and was associated with lower procedural success and higher MACE.

Radial access for chronic total occlusion percutaneous coronary intervention: Insights from the PROGRESS-CTO registry.

Use of radial access for chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has been increasing. We examined the clinical characteristics and procedural outcomes of patients who underwent CTO PCI with radial versus femoral access in the Prospective Global Registry for the Study of CTO Intervention (PROGRESS-CTO, NCT02061436). Of 10,954 patients who underwent CTO PCI at 55 centers in 7 countries between 2012 and 2022, 2578 (24%) had a radial only approach. Patients who underwent radial only access were younger (63 ± 10 vs. 65 ± 10, years, p &lt; 0.001), more likely to be men (84% vs. 81%, p = 0.001), and had significantly lower prevalence of comorbidities compared with the femoral access group including diabetes mellitus (39% vs. 45%, p &lt; 0.001) and coronary artery bypass graft surgery (57% vs. 64%, p &lt; 0.001). In addition, radial only cases had lower angiographic complexity with lower J-CTO and PROGRESS-CTO scores. After adjusting for potential confounders, radial only access was associated with lower risk of access site complications (odds ratio [OR]: 0.45, 95% confidence interval [CI]: 0.22-0.91), similar technical success (OR: 0.87, 95% CI: 0.74-1.04) and major adverse cardiovascular events (MACE) (OR: 0.65, 95% CI: 0.40-1.07), compared with the femoral access group. Radial only access was used in 24% of CTO PCIs and was associated with lower access site complications, and similar technical success and MACE as compared with the femoral access group.

Antegrade dissection and re-entry versus parallel wiring in chronic total occlusion percutaneous coronary intervention: Insights from the PROGRESS-CTO registry.

BACKGROUND: The comparative efficacy and safety of parallel wiring versus antegrade dissection and re-entry (ADR) in chronic total occlusion (CTO) percutaneous coronary intervention (PCI) is controversial. METHODS: We compared the clinical and angiographic characteristics and outcomes of parallel wiring versus ADR after failed antegrade wiring in a large, multicenter CTO PCI registry. RESULTS: A total of 1725 CTO PCI procedures with failed antegrade wiring with a single wire were approached with parallel wiring (692) or ADR (1033) at the discretion of the operator. ADR patients were older (65 ± 10 vs. 62 ± 10, years, p < 0.001) and had higher prevalence of comorbidities, such as diabetes mellitus (43% vs. 32%, p < 0.001), prior coronary artery bypass graft surgery (31% vs. 19%, p < 0.001), and lower left ventricular ejection fraction (50 ± 14 vs. 53 ± 11%, p < 0.001). The ADR group had higher J-CTO (2.8 ± 1.1 vs. 2.1 ± 1.3, p < 0.001) and PROGRESS-CTO (1.6 ± 1.1 vs. 1.2 ± 1.0, p < 0.001) scores. Equipment use including guidewires, balloons, and microcatheters was higher, and the procedures lasted longer in the ADR group. Technical success (78% vs. 75%, p = 0.046) and major adverse cardiovascular events (composite of all-cause mortality, stroke, acute myocardial infarction, emergency surgery or re-PCI, and pericardiocentesis) (3.7% vs. 1.9%, p = 0.029) were higher in the ADR group, with similar procedural success (75% vs. 73%, p = 0.166). CONCLUSION: In lesions that could not be crossed with antegrade wiring, ADR was associated with higher technical but not procedural success, and also higher MACE compared with parallel wiring.

Gender differences in chronic total occlusion percutaneous coronary interventions: Insights from the PROGRESS-CTO registry.

BACKGROUND: There are limited data describing gender differences in patients undergoing chronic total occlusion (CTO) percutaneous coronary interventions (PCI). METHODS: We compared baseline clinical and angiographic characteristics and procedural outcomes between men and women among 9457 CTO PCIs performed at 38 centers between 2012 and 2022. RESULTS: A total of 7687 (81%) men and 1770 (19%) women were treated. Women were older, more likely to have comorbidities such as diabetes, hypertension and peripheral arterial disease, and had higher left ventricular ejection fraction. The most common CTO target vessel was the right coronary artery for both men (53%) and women (52%), although the left anterior descending artery was more frequently the target vessel among women (31% vs. 25%; p < 0.001). The J-CTO score (2.4 ± 1.3 vs. 2.2 ± 1.2; p < 0.001) as well as the PROGRESS-CTO score (1.3 ± 1.0 vs. 1.1 ± 1.0; p < 0.001) were higher among men. In female patients, antegrade wiring was more frequently the initial crossing strategy (87.6% vs. 82.4%; p < 0.001) and was more successful in crossing the target lesion (62.7% vs. 54.0%; p < 0.001) compared with men. Interventions in men required longer procedure time and fluoroscopy time, as well as higher air kerma radiation dose and contrast volume when compared to women. Technical (89% vs. 86%; p < 0.001) and procedural (87% vs. 84%; p = 0.003) success rates were higher among women. In-hospital major adverse cardiovascular events (MACE) were also higher in women (2.9% vs. 1.8%; p < 0.001). CONCLUSIONS: Women undergoing CTO PCI had higher technical and procedural success rates, but also higher in-hospital MACE compared with men.

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.

Intravascular lithotripsy in chronic total occlusion percutaneous coronary intervention: Insights from the PROGRESS-CTO registry.

BACKGROUND: The use of intravascular lithotripsy (IVL) in chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has received limited study. METHODS: We analyzed the baseline clinical and angiographic characteristics and procedural outcomes of 82 CTO PCIs that required IVL at 14 centers between 2020 and 2022. RESULTS: During the study period, IVL was used in 82 of 3301 (2.5%) CTO PCI procedures (0.4% in 2020 and 7% in 2022; p for trend < 0.001). Mean patient age was 69 ± 11 years and 79% were men. The prevalence of hypertension (95%), diabetes mellitus (62%), and prior PCI (61%) was high. The most common target vessel was the right coronary artery (54%), followed by the left circumflex (23%). The mean J-CTO and PROGRESS-CTO scores were 2.8 ± 1.1 and 1.3 ± 1.0, respectively. Antegrade wiring was the final successful crossing strategy in 65% and the retrograde approach was used in 22%. IVL was used in 10% of all heavily calcified lesions and 11% of all balloon undilatable lesions. The 3.5 mm lithotripsy balloon was the most commonly used balloon (28%). The mean number of pulses per lithotripsy run was 33 ± 32 and the median duration of lithotripsy was 80  (interquartile range: 40-103) seconds. Technical and procedural success was achieved in 77 (94%) and 74 (90%) cases, respectively. Two (2.4%) Ellis Class 2 perforations occurred after IVL use and were managed conservatively. CONCLUSION: IVL is increasingly being used in CTO PCI with encouraging outcomes.

An algorithmic approach to balloon-uncrossable coronary lesions.

Balloon uncrossable coronary lesions are lesions that cannot be crossed with a balloon after successful guidewire crossing. The strategies used to facilitate the treatment of such lesions can be classified into strategies that provide lesion modification and strategies that increase support. We describe a systematic, algorithmic approach to treat balloon uncrossable lesions, starting with use of small balloons, followed by increase in guide catheter support, use of microcatheters, wire cutting or puncture techniques, laser, atherectomy, and subintimal modification techniques. Sequential and simultaneous application of the aforementioned techniques can result in successful treatment of these challenging lesions.

Guiding Principles for Chronic Total Occlusion Percutaneous Coronary Intervention.

Outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) have improved because of advancements in equipment and techniques. With global collaboration and knowledge sharing, we have identified 7 common principles that are widely accepted as best practices for CTO-PCI. 1. Ischemic symptom improvement is the primary indication for CTO-PCI. 2. Dual coronary angiography and in-depth and structured review of the angiogram (and, if available, coronary computed tomography angiography) are key for planning and safely performing CTO-PCI. 3. Use of a microcatheter is essential for optimal guidewire manipulation and exchanges. 4. Antegrade wiring, antegrade dissection and reentry, and the retrograde approach are all complementary and necessary crossing strategies. Antegrade wiring is the most common initial technique, whereas retrograde and antegrade dissection and reentry are often required for more complex CTOs. 5. If the initially selected crossing strategy fails, efficient change to an alternative crossing technique increases the likelihood of eventual PCI success, shortens procedure time, and lowers radiation and contrast use. 6. Specific CTO-PCI expertise and volume and the availability of specialized equipment will increase the likelihood of crossing success and facilitate prevention and management of complications, such as perforation. 7. Meticulous attention to lesion preparation and stenting technique, often requiring intracoronary imaging, is required to ensure optimum stent expansion and minimize the risk of short- and long-term adverse events. These principles have been widely adopted by experienced CTO-PCI operators and centers currently achieving high success and acceptable complication rates. Outcomes are less optimal at less experienced centers, highlighting the need for broader adoption of the aforementioned 7 guiding principles along with the development of additional simple and safe CTO crossing and revascularization strategies through ongoing research, education, and training.

Succesful antegrade subintimal bypass restenting of in-stent chronic total occlusion.

Coronary chronic total occlusions (CTOs) are known to cause significant patient morbidity. Over the past several years, the techniques and devices for treating these CTOs have advanced tremendously. The interventional management of CTOs within previously placed coronary stents, however, remains challenging. Here, we present a case of an in-stent restenosis of the right coronary artery CTO bypassed using a controlled subintimal dissection re-entry technique via antegrade approach creating side-by-side stents.

Predicting Successful Chronic Total Occlusion Crossing With Primary Antegrade Wiring Using Machine Learning.

BACKGROUND: There is limited data on predicting successful chronic total occlusion crossing using primary antegrade wiring (AW). OBJECTIVES: The aim of this study was to develop and validate a machine learning (ML) prognostic model for successful chronic total occlusion crossing using primary AW. METHODS: We used data from 12,136 primary AW cases performed between 2012 and 2023 at 48 centers in the PROGRESS CTO registry (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention; NCT02061436) to develop 5 ML models. Hyperparameter tuning was performed for the model with the best performance, and the SHAP (SHapley Additive exPlanations) explainer was implemented to estimate feature importance. RESULTS: Primary AW was successful in 6,965 cases (57.4%). Extreme gradient boosting was the best performing ML model with an average area under the receiver-operating characteristic curve of 0.775 (± 0.010). After hyperparameter tuning, the average area under the receiver-operating characteristic curve of the extreme gradient boosting model was 0.782 in the training set and 0.780 in the testing set. Among the factors examined, occlusion length had the most significant impact on predicting successful primary AW crossing followed by blunt/no stump, presence of interventional collaterals, vessel diameter, and proximal cap ambiguity. In contrast, aorto-ostial lesion location had the least impact on the outcome. A web-based application for predicting successful primary AW wiring crossing is available online (PROGRESS-CTO website) (https://www.progresscto.org/predict-aw-success). CONCLUSIONS: We developed an ML model with 14 features and high predictive capacity for successful primary AW in chronic total occlusion percutaneous coronary intervention.

Predictors of successful primary antegrade wiring in chronic total occlusion percutaneous coronary intervention.

BACKGROUND: Antegrade wiring is the most commonly used chronic total occlusion (CTO) crossing technique. METHODS: Using data from the PROGRESS CTO registry (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention; Clinicaltrials.gov identifier: NCT02061436), we examined the clinical and angiographic characteristics and procedural outcomes of CTO percutaneous coronary interventions (PCIs) performed using a primary antegrade wiring strategy. RESULTS: Of the 13 563 CTO PCIs performed at 46 centers between 2012 and 2023, a primary antegrade wiring strategy was used in 11 332 (83.6%). Upon multivariable logistic regression analysis, proximal cap ambiguity (odds ratio [OR]: 0.52; 95% CI, 0.46-0.59), side branch at the proximal cap (OR: 0.85; 95% CI, 0.77-0.95), blunt/no stump (OR: 0.52; 95% CI: 0.47-0.59), increasing lesion length (OR [per 10 mm increase]: 0.79; 95% CI, 0.76-0.81), moderate to severe calcification (OR: 0.73; 95% CI, 0.66-0.81), moderate to severe proximal tortuosity (OR: 0.67; 95% CI, 0.59-0.75), bifurcation at the distal cap (OR: 0.66; 95% CI, 0.59-0.73), left anterior descending artery CTO (OR [vs right coronary artery]: 1.44; 95% CI, 1.28-1.62) and left circumflex CTO (OR [vs right coronary artery]: 1.22; 95% CI, 1.07-1.40), non-in-stent restenosis lesion (OR: 0.56; 95% CI, 0.49-0.65), and good distal landing zone (OR: 1.18; 95% CI, 1.06-1.32) were independently associated with primary antegrade wiring crossing success. CONCLUSIONS: The use of antegrade wiring as the initial strategy was high (83.6%) in our registry. We identified several parameters associated with primary antegrade wiring success.

Racial disparities in chronic total occlusion percutaneous coronary interventions: insights from the PROGRESS-CTO registry.

OBJECTIVES: There is limited data on race and outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). The authors sought to evaluate CTO PCI techniques and outcomes in different racial groups. METHODS: We examined the baseline characteristics and procedural outcomes of 11 806 CTO PCIs performed at 44 US and non-US centers between 2012 and March 2023. In-hospital major adverse cardiac events (MACE) included death, myocardial infarction, repeat target-vessel revascularization, pericardiocentesis, cardiac surgery, and stroke prior to discharge. RESULTS: The most common racial group was White (84.5%), followed by Black (5.7%), "Other" (3.9%), Hispanic (2.9%), Asian (2.4%), and Native American (0.7%). There were significant differences in the baseline characteristics between different racial groups. When compared with non-White patients, the retrograde approach and antegrade dissection re-entry were more likely to be the successful crossing strategies in White patients without any significant differences in technical success (86.4% vs 86.4%; P = .93), procedural success (84.8% vs 85.0%; P = .79), and in-hospital MACE (2.0% vs 1.5%; P = .15) between the 2 groups. The technical success rate was significantly higher in the "Other" racial group (91.0% vs 86.4% in White, 86.9% in Asian, 84.5% in Black, 84.5% in Hispanic, and 83.3% in Native American; P = .03) without any significant differences in procedural success or in-hospital MACE rates between the groups. CONCLUSIONS: Despite differences in baseline characteristics and procedural techniques, the procedural success and in-hospital MACE of CTO PCI were not significantly different between most racial groups.

Reverse Takotsubo cardiomyopathy in the setting of anaphylaxis treated with high-dose intravenous epinephrine.

BACKGROUND: Takotsubo cardiomyopathy is seen, though rarely, in anaphylaxis treated with epinephrine. Stress cardiomyopathy is most likely to occur in middle-aged women. The underlying etiology is believed to be related to catecholamine release in periods of intense stress. Catecholamines administered exogenously, and those secreted by neuroendocrine tumors (e.g., pheochromocytoma) or during anaphylaxis have been reported to cause apical ballooning syndrome, or takotsubo syndrome. However, reverse takotsubo stress cardiomyopathy is rarely seen or reported in anaphylaxis treated with epinephrine. OBJECTIVES: To report a case illustrating that high-dose intravenous epinephrine can trigger stress cardiomyopathy, and that the risk is heightened with inappropriate dosing in the treatment of anaphylaxis. CASE REPORT: We report a rare case of iatrogenic reverse takotsubo syndrome in a young woman who was inappropriately treated with high-dose intravenous epinephrine for mild anaphylaxis. CONCLUSION: Inappropriately high doses of intravenous epinephrine can trigger stress cardiomyopathy. Emergency physicians should be familiar with the diagnosis, grading, and appropriate treatments of anaphylaxis to avoid this unnecessary complication.