Coronary Risk in Transcatheter Aortic Valve Replacement, Overview of Data, Challenges, and Best Practices.

Coronary artery obstruction is a rare complication of transcatheter aortic valve replacement (TAVR). This risk increases in TAVR-valve-in-valve procedure. Several anatomic risk factors were described in many studies to identify the predictive elements of coronary artery occlusion on computed tomography cardiac scan. Rescue percutaneous coronary intervention was the first approach described to treat this complication with a high mortality rate. Later on, preventive chimney stenting technique was evaluated and results showed that is a safe and effective strategy but it leads to a difficult coronary access later. New preventive techniques are being evaluated recently (Basilica and Shorctut).

Impact of Bifurcation Involvement and Location in Chronic Total Occlusion Percutaneous Coronary Intervention: Insights From the EuroCTO Registry.

Bifurcation involvement close to or within the occluded segment poses increasing difficulties for chronic total occlusion (CTO)-percutaneous coronary intervention (PCI). However, this variable is not considered in the angiography-based CTO scoring systems nor has been extensively investigated in large multicenter series. Accordingly, we analyzed a CTO-PCI registry involving 92 European centers to explore the incidence, angiographic and procedural characteristics, and outcomes specific to CTO-PCIs with bifurcation involvement. A total of 3,948 procedures performed between January and November 2023 were examined (33% with bifurcation involvement). Among bifurcation lesions, 38% and 37% were located within 5 mm of the proximal and distal cap, respectively, 16% within the CTO body, and in 9% of cases proximal and distal bifurcations coexisted. When compared with lesions without bifurcation involvement, CTO bifurcation lesions had higher complexity (J-CTO 2.33 ± 1.21 vs 2.11 ± 1.27, p <0.001) and were associated with higher use of additional devices (dual-lumen microcatheter in 27.6% vs 8.4%, p <0.001, and intravascular ultrasound in 32.2% vs 21.7%, p <0.001). Radiation dose (1,544 [836 to 2,819] vs 1,298.5 [699.1 to 2,386.6] mGy, p <0.001) and contrast volume (230 [160 to 300] vs 190 [130 to 250] ml, p <0.001) were also higher. Technical success was similar (91.5% with bifurcation involvement vs 90.4% without bifurcation involvement, p = 0.271). However, the bifurcation lesions within the CTO segment (intralesion) were associated with lower technical success than the other bifurcation-location subgroups (83.7% vs 93.3% proximal, 93.4% distal, and 89.0% proximal and distal, p <0.001). On multivariable analysis, the presence of an intralesion bifurcation was independently associated with technical failure (odds ratio 2.04, 95% confidence interval 1.24 to 3.35, p = 0.005). In conclusion, bifurcations are present in approximately one-third of CTOs who underwent PCI. PCI of CTOs with bifurcation can be achieved with high success rates except for bifurcations within the occluded segment, which were associated with higher technical failure.

N terminal pro-brain natriuretic peptide level and benefits of chronic total occlusion revascularization.

BACKGROUND: The management of revascularization of chronic total occlusions (CTOs) remains controversial. Whether specific patients gain survival benefit from CTO revascularization remains unknown. OBJECTIVES: We investigated whether (i) patients with CTO have higher N terminal pro-brain natriuretic peptide (NT pro-BNP) levels than patients without CTO, (ii) in patients with CTO, NT pro-BNP levels predict adverse events, and (iii) those with elevated levels benefit from revascularization. METHODS: In 392 patients with stable, significant coronary artery disease (CAD) and CTO undergoing coronary angiography, rates of all-cause mortality, cardiovascular death, and a composite (cardiovascular death, myocardial infarction and heart failure hospitalizations) were investigated. Unadjusted and adjusted Cox proportional and Fine and Gray sub-distribution hazard models were performed to determine the association between NT pro-BNP levels and incident event rates in patients with CTO. RESULTS: NT pro-BNP levels were higher in patients with, compared to those without CTO (median 230.0 vs. 177.7 pg/mL, p ≤0.001). Every doubling of NT pro-BNP level in patients with CTO was associated with a > 25% higher rate of adverse events. 111 (28.5%) patients underwent CTO revascularization. In patients with elevated NT pro-BNP levels (> 125 pg/mL), those who underwent CTO revascularization had substantially lower adverse event rates compared to patients without CTO revascularization (adjusted cardiovascular death hazard ratio 0.29, 95% confidence interval (0.09-0.88). However, in patients with low NT pro-BNP levels (≤ 125 pg/mL), event rates were similar in those with and without CTO revascularization. CONCLUSION: NT pro-BNP levels can help identify individuals who may benefit from CTO revascularization.

Full-Moon Coronary Calcification as Detected With Computed Tomography Angiography in Chronic Total Occlusion Percutaneous Coronary Intervention.

"Full moon" is a central calcification that occludes the entire vessel on coronary computed tomography angiography (CCTA). We examined the association of full moon calcification as identified by CCTA, on clinical and procedural outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). We studied patients who underwent elective CTO-PCI in 2 European centers and had preprocedural CCTA. The primary end point was the inability to cross the lesion and/or the need for extensive debulking techniques. Secondary end points were procedural success, in-hospital cardiac mortality, the need for extensive debulking techniques, myocardial infarction, major adverse cardiac events (defined as in-hospital death, myocardial infarction, and clinically driven target vessel revascularization), and stent thrombosis. Secondary procedural end points included procedural time, fluoroscopy time, number of guidewires and balloons, stent length, number and diameter, and contrast volume. Multivariable logistic regression analysis was performed, identifying potential covariates related to the primary outcome according to knowledge and previous studies. Subsequently, a stepwise selection approach was performed to select factors with the greatest predictive value. Of 140 patients included, 28 (20%) had a full moon calcified CTO plaque. Patients in the full moon group were older and had more cardiovascular risk factors. There was not significant difference in the need for retrograde approach and anterograde dissection and reentry techniques between the full moon group and the other groups (32.1% vs 37.5%, p = 0.59 and 0% vs 1.7%, p = 0.47, respectively). Patients in the full moon group had greater incidence of the primary outcome than did those who did not have full moon morphology (53.5% vs 12.5%, p <0.001). On multivariable analysis that included chronic kidney failure and previous coronary artery bypass surgery, full moon calcification was associated with greater incidence of the primary end point (odds ratio 6.5, 95% confidence interval 2.1 to 20.5, p = 0.001). Moreover, less procedural success (71.4% vs 87.5%, p = 0.03), greater incidence of coronary perforations (14.2% vs 3.5%, p <0.02), and greater procedural (172.5 [118.0 to 237.5] vs 144.0 [108.50 to 174.75], p = 0.02) and fluoroscopic time (62.6 [38.1 to 83.0] vs 42.8 [29.5 to 65.7], p = 0.03) were observed in the full moon group. Overall major adverse cardiac events did not differ between the 2 groups (1 patient in the full moon group vs 1 patient in the non-full moon group; 3.5% vs 0.8%, p = 0.29). In conclusion, full moon calcification on CCTA was independently associated with procedural complexity and adverse outcomes in CTO-PCI.

Restoration of Epicardial Blood Flow After Left Ventricular Unloading With the Impella CP Heart Pump in a Patient With STEMI Treated With Surgical Revascularization.

Left main occlusion presenting as ST-segment elevation myocardial infarction is an exceedingly morbid condition. This article reports a case of cardiac arrest in a patient after a treadmill stress test. Coronary angiography revealed 100% occlusion of the left main coronary artery. Left ventricular unloading with the Impella CP heart pump (ABIOMED/Johnson & Johnson MedTech) was used, after which epicardial blood flow was restored without angioplasty. The patient underwent surgical revascularization. Despite a prolonged revascularization time, there was no evidence of severe myocardial injury postoperatively.

Development of a Novel Nomogram to Predict Major Adverse Cardiac Events in Patients with Chronic Total Occlusion.

Objectives: To create a nomogram using single photon emission computed tomography (SPECT) myocardial perfusion imaging and 18F-FDG positron emissions tomography (PET) gated myocardial metabolism imaging to forecast major adverse cardiovascular events (MACE) in chronic total occlusion (CTO) patients treated with optimal medical therapy (OMT). Methods: A total of 257 patients who received OMT between January 2016 and December 2021 were included in this retrospective study. Patients were randomly divided into development (n=179) and validation (n=78) cohorts. A thorough evaluation was conducted, encompassing clinical features and imaging analysis, which involved assessing myocardial perfusion and metabolism. Independent risk factors were identified using least absolute shrinkage and selection operator (LASSO) and multivariate Cox regression analyses. Calibration curves and decision curve analysis (DCA) were used to evaluate the clinical usefulness. Results: In the development cohort, 53 patients (29.6%) experienced MACE out of 179 patients, while in the validation cohort, MACE occurred in 23 (29.5%) patients out of 78. The PET-left ventricular end-systolic volume (P-ESV) (HR 1.01; 95% CI 1.003-1.017; p=0.003), hibernating myocardium / total perfusion defect (HM/TPD) (HR 1.053; 95% CI 1.038-1.069; p<0.001), PET-left ventricular ejection fraction (P-LVEF) (HR 0.862; 95% CI 0.788-0.943; p=0.001), and left anterior descending branch (LAD) (HR 2.303; 95% CI 1.086-4.884; p=0.03) were significantly associated with MACE and were used to develop the nomogram. The nomogram demonstrated excellent discrimination with C-indexes of 0.931 and 0.911 in the development and validation cohorts. DCA determined that the model exhibited a considerably superior net advantage in predicting MACE. Conclusion: A new nomogram integrating clinical factors and imaging features was created to predict the risk of MACE in patients with CTO.

Transcoronary Gradients of Mechanosensitive MicroRNAs as Predictors of Collateral Development in Chronic Total Occlusion.

Background and Objectives: In this present study, we investigated the impact of mechanosensitive microRNAs (mechano-miRs) on the collateral development in 126 chronic total occlusion (CTO) patients, selected from 810 undergoing angiography. Materials and Methods: We quantified the collateral blood supply using the collateral flow index (CFI) and assessed the transcoronary mechano-miR gradients. Results: The patients with favorable collaterals had higher CFI values (0.45 ± 0.02) than those with poor collaterals (0.38 ± 0.03, p < 0.001). Significant differences in transcoronary gradients were found for miR-10a, miR-19a, miR-21, miR-23b, miR-26a, miR-92a, miR-126, miR-130a, miR-663, and let7d (p < 0.05). miR-26a and miR-21 showed strong positive correlations with the CFI (r = 0.715 and r = 0.663, respectively), while let7d and miR-663 were negatively correlated (r = -0.684 and r = -0.604, respectively). The correlations between cytokine gradients and mechano-miR gradients were also significant, including Transforming Growth Factor Beta with miR-126 (r = 0.673, p < 0.001) and Vascular Endothelial Growth Factor with miR-10a (r = 0.602, p = 0.002). A regression analysis highlighted the hemoglobin level, smoking, beta-blocker use, miR-26a, and miR-663 as significant CFI determinants, indicating their roles in modulating the collateral vessel development. Conclusions: These findings suggest mechanosensitive microRNAs as predictive biomarkers for collateral circulation, offering new therapeutic perspectives for CTO patients.

Chronic Total Occlusions: A State-of-the-Art Review.

The percutaneous management of chronic total occlusions (CTO) is a well-established sub-specialty of Interventional Cardiology, requiring specialist equipment, training, and techniques. The heterogeneity of approaches in CTO has led to the generation of multiple algorithms to guide operators in their management. The evidence base for management of CTOs has suffered from inconsistent descriptive and quantitative terminology in defining the nature of lesions and techniques utilised, as well as seemingly contradictory data about improvement in ventricular function, symptoms of angina, and mortality from large-scale registries and randomised controlled trials. Through this review, we explore the history of CTO management and its supporting evidence in detail, with an outline of limitations of CTO-percutaneous coronary intervention and a look at the future of this growing field within cardiology.

Circulating Progenitor Cells and Coronary Collaterals in Chronic Total Occlusion.

BACKGROUND: The role of circulating progenitor cells (CPC) in collateral formation that occurs in the presence of chronic total occlusions (CTO) of a coronary artery is not well established. In stable patients with a CTO, we investigated whether CPC levels are associated with (a) collateral development and (b) ischemic burden, as measured by circulating high sensitivity troponin-I (hsTn-I) levels. METHODS: CPCs were enumerated by flow cytometry as CD45med+ blood mononuclear cells expressing CD34 and both CD34 and CD133 epitopes. The association between CPC counts and both Rentrop collateral grade (0, 1, 2, or 3) and hsTn-I levels were evaluated using multivariate regression analysis, after adjusting for demographic and clinical characteristics. RESULTS: In 89 patients (age 65.5, 72% male, 27% Black), a higher CPC count was positively associated with a higher Rentrop collateral grade; [CD34+ adjusted odds ratio (OR) 1.49 95% confidence interval (CI) (0.95, 2.34) P = 0.082] and [CD34+/CD133+ OR 1.57 95% CI (1.05, 2.36) P = 0.028]. Every doubling of CPC counts was also associated with lower hsTn-I levels [CD34+ ß -0.35 95% CI (-0.49, -0.15) P = 0.002] and [CD34+/CD133+ ß -0.27 95% CI (-0.43, -0.08) P = 0.009] after adjustment. CONCLUSION: Individuals with higher CPC counts have greater collateral development and lower ischemic burden in the presence of a CTO.

Self-Apposing Stents in Coronary Chronic Total Occlusions: A Pilot Study.

OBJECTIVES: This pilot study assessed the 12-month angiographic and clinical outcomes of self-apposing (SA) stents in patients undergoing chronic total occlusion (CTO) percutaneous coronary intervention (PCI). BACKGROUND: Self-apposing (SA) stents may decrease incomplete strut apposition and stent strut coverage that are common after CTO PCI. METHODS: We compared 20 patients who underwent CTO PCI using SA drug-eluting stents (DESs) with 20 matched control patients who underwent CTO PCI using balloon-expandable (BE)-DESs. All patients were followed up clinically for 12 months and had coronary angiography with optical coherence tomography at the end of the follow-up period. The primary end points were stent strut malapposition and strut coverage. The secondary end point was composite major adverse cardiovascular events (MACEs) at 12 months. RESULTS: Both groups had high prevalence of diabetes mellitus, and most of the treated lesions were complex, with 62% having a J-CTO score of ≥3. All CTO PCI techniques were allowed for recanalisation, and 75% of the procedures were guided by intravascular ultrasound. At 12 months, the SA-DES group had fewer malapposed struts (0% [interquartile range (IQR) 0%-0%] vs 4.5% [IQR 0%-20%]; p<0.001) and uncovered struts (0.08% [IQR 0%-1.6%] vs 8.2% [IQR 0%-16%]; p<0.001). However, they showed significantly higher rates of MACEs due to clinically-driven target lesion revascularisation (45% vs 15%; p=0.038). CONCLUSIONS: In this pilot study, compared with conventional BE-DESs, SA-DESs used in CTO PCI were associated with fewer malapposed and uncovered stent struts but also with significantly higher rates of in-stent restenosis and MACEs, mainly caused by clinically driven target lesion revascularisation.

Successful true cavity pathfinding with balloon assisted CTO with bifurcation lesions: Two case reports.

BACKGROUND: Coronary artery disease is a prevalent global cardiovascular ailment, with percutaneous coronary intervention (PCI) standing out as a crucial method for relieving symptoms and enhancing the quality of life in patients with coronary heart disease. However, the presence of concurrent chronic total occlusion (CTO) and bifurcation lesions within coronary arteries elevates the complexity and treatment risks, especially when the entry point of the CTO is ambiguous. OBJECTIVE: This study aims to present an innovative approach for treating CTO complicated with bifurcation lesions, focusing on true cavity pathfinding assisted by a balloon. METHODS: Two cases of CTO patients with concomitant bifurcation lesions are described. One case involves CTO of the left anterior descending artery) combined with anterior non-angle trigeminal lesions, while the other entails CTO of the posterior left artery combined with posterior angle trigeminal lesions. True lumen identification using a balloon and subsequent opening of the CTO blood vessel were performed in both cases. RESULTS: In both cases, the true lumen was successfully located with the assistance of a balloon, leading to the successful opening of the CTO blood vessel. This approach not only simplified the procedure but also reduced procedural difficulty and associated risks of complications compared to traditional guide wire operations. CONCLUSION: The application of true cavity pathfinding assisted by a balloon offers a novel and effective strategy for managing CTO complicated with bifurcation lesions. The method simplifies the procedure, decreases procedural difficulty, and lowers the risk of complications associated with guide wire operations. However, further studies and long-term follow-up data are warranted to validate the reliability and long-term efficacy of this innovative approach.

Outcomes following coronary chronic total occlusion revascularization with drug-coated balloons.

OBJECTIVES: Despite the introduction of improved drug eluting stents (DES), the rate of repeat revascularization procedures following percutaneous coronary interventions (PCI) in coronary chronic total occlusions (CTO) remains high. By leaving vessels uncaged and limiting length of stented segments, drug-coated balloons (DCB) represent an appealing alternative to DES for CTO-PCI. Since data supporting the use of DCBs in CTO-PCI is scarce, we compared the outcomes of patients undergoing CTO-PCI involving DCBs vs DES only. METHODS: From 2 prospective registries, outcomes of patients undergoing CTO-PCI involving DCBs and those undergoing PCI with DES only were compared. Outcomes included major adverse cardiac and cerebrovascular events (MACCE) and cardiovascular death (CV-death). RESULTS: Overall, 157 patients were studied; 112 (71%) underwent CTO-PCI involving DCBs and 45 (29%) were treated with DES only. Mean J-CTO score was 1.84 ± 0.7. Most CTO-lesions involved the right coronary artery, 88 (56%), and 26 (17%) cases were in-stent occlusions. In the DCB group, 46 (41%) lesions were treated with DCBs alone. Mean lengths of the stented segments in the DCB vs DES cohorts were 59 ± 28 mm vs 87 ± 37 mm (P less than .001), respectively. After 12 months, the MACCE rate was higher in the DES only vs DCB group (26% vs 11%, P=.03). Length of the stented segment was an independent predictor for MACCE (HR 1.15 [95% CI, 1.05-1.26] per 10-mm stent length). CONCLUSIONS: Revascularization of CTO lesions involving DCBs appears safe and potentially lowers MACCE rates compared to treatment with DES alone. Importantly, using DCBs for CTO treatment may reduce total stent length, which determines PCI outcomes.

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.

Radiation dose during contemporary percutaneous coronary interventions for chronic total occlusion: insights from the PROGRESS-CTO registry.

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) is associated with high radiation doses. In this manuscript, we examined the contemporary trends and determinants of radiation dose in the PROGRESS CTO (Prospective Global Registry for the Study of CTO Intervention; Clinicaltrials.gov identifier: NCT02061436) registry. Radiation dose during CTO PCI did not change significantly since 2020, highlighting the need for innovation and operator education to further maintain radiation safety.

Validation of the J-Channel Score for retrograde channel crossing in the PROGRESS-CTO registry.

Successful collateral channel (CC) crossing is essential for the success of retrograde chronic total occlusion (CTO) percutaneous coronary intervention (PCI). Based on the Japanese CTO PCI expert registry, the J-Channel score was developed to predict CC crossing. We examined the performance of the J-Channel score in patients who underwent retrograde CTO-PCI at 31 centers between 2013-2023 as part of the Prospective Global Registry for the Study of CTO Intervention (PROGRESS-CTO). We observed an association between successful CC crossing and the J-Channel score, its predictive efficacy was modest for both wire and microcatheter crossing.

Equipment entrapment/loss during chronic total occlusion percutaneous coronary intervention.

BACKGROUND: There is limited data on equipment loss or entrapment during chronic total occlusion (CTO) percutaneous coronary intervention (PCI). METHODS: We analyzed the baseline clinical and angiographic characteristics and outcomes of equipment loss/entrapment at 43 US and non-US centers between 2017 and 2023. RESULTS: Equipment loss/entrapment was reported in 40 (0.4%) of 10 719 cases during the study period. These included guidewire entrapment/fracture (n = 21), microcatheter entrapment/fracture (n = 11), stent loss (n = 8) and balloon entrapment/fracture/rupture (n = 5). The equipment loss/entrapment cases were more likely to have moderate to severe calcification, longer lesion length, higher J-CTO and PROGRESS-CTO complications scores, and use of the retrograde approach compared with the remaining cases. Retrieval was attempted in 71.4% of the guidewire, 90.9% of the microcatheter, 100% of the stent loss, and 100% of the balloon cases, and was successful in 26.7%, 30.0%, 50%, and 40% of the cases, respectively. Procedures complicated by equipment loss/entrapment had higher procedure and fluoroscopy time, contrast volume and patient air kerma radiation dose, lower procedural (60.0% vs 85.6%, P less than .001) and technical (75.0% vs 86.8%, P = .05) success, and higher incidence of major adverse cardiac events (MACE) (17.5% vs 1.8%, P less than .001), acute MI (7.5% vs 0.4%, P less than .001), emergency coronary artery bypass graft (CABG) (2.5% vs 0.1%, P = .03), perforation (20.0% vs 4.9%, P less than .001), and death (7.5% vs 0.4%, P less than .001). CONCLUSIONS: Equipment loss is a rare complication of CTO PCI; it is more common in complex CTOs and is associated with lower technical success and higher MACE.