Systematic review and meta-analysis of diagnostic test accuracy of ST-segment elevation for acute coronary occlusion

OBJECTIVE

To evaluate the diagnostic sensitivity and specificity of ST-segment elevation on a 12‑lead ECG in detecting ACO across any coronary artery, challenging the current STEMI-NSTEMI paradigm.

METHODS

Studies from MEDLINE and Scopus (2012-2023) comparing ECG findings with coronary angiograms were systematically reviewed and analyzed following PRISMA-DTA guidelines. QUADAS-2 assessed the risk of bias.

STUDY SELECTION

Studies included focused on AMI patients and provided data enabling the construction of contingency tables for sensitivity and specificity calculation, excluding those with non-ACS conditions, outdated STEMI criteria, or a specific focus on bundle branch blocks or other complex diagnoses. Data were extracted systematically and pooled test accuracy estimates were computed using MetaDTA software, employing bivariate analyses for within- and between-study variation. The primary outcomes measured were the sensitivity and specificity of ST-segment elevation in detecting ACO.

RESULTS

Three studies with 23,704 participants were included. The pooled sensitivity of ST-segment elevation for detecting ACO was 43.6% (95% CI: 34.7%-52.9%), indicating that over half of ACO cases may not exhibit ST-segment elevation. The specificity was 96.5% (95% CI: 91.2%-98.7%). Additional analysis using the OMI-NOMI strategy showed improved sensitivity (78.1%, 95% CI: 62.7%-88.3%) while maintaining similar specificity (94.4%, 95% CI: 88.6%-97.3%).

CONCLUSION

The findings reveal a significant diagnostic gap in the current STEMI-NSTEMI paradigm, with over half of ACO cases potentially lacking ST-segment elevation. The OMI-NOMI strategy could offer an improved diagnostic approach. The high heterogeneity and limited number of studies necessitate cautious interpretation and further research in diverse settings.

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.

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.

Clinical outcomes of percutaneous coronary intervention in chronic total occlusion in patients with type 2 diabetes mellitus

INTRODUCTION AND OBJECTIVES

Coronary chronic total occlusions (CTOs) are relatively common findings in patients with type 2 diabetes mellitus (T2DM). However, the indication for percutaneous coronary intervention (PCI) and its clinical benefit in these patients remain controversial.

METHODS

A single-center retrospective cohort study with prospectively collected outcomes was carried out with CTO patients undergoing PCI in 2019 and 2020. Patients were divided into two groups according to previous T2DM diagnosis (T2DM and non-T2DM). The primary outcome was recurrence of angina and/or heart failure symptoms and secondary outcomes were myocardial infarction and all-cause mortality.

RESULTS

A total of 177 patients (82.5% male) were included in the analysis, with a mean age of 65±11 years. The primary outcome (total symptom recurrence) occurred in 16.6% of the sample, with no difference between groups (non-T2DM 13.6% vs. T2DM 21.2%, p=0.194) in a two-year follow-up. Angina recurrence was significantly more frequent in T2DM patients (15.2%, p=0.043). The presence of T2DM was not an independent predictor of symptom recurrence (p=0.429, HR 1.37, 95% CI 0.62-2.98). Myocardial infarction and all-cause mortality were also not different between groups (T2DM 1.5%, p=0.786 and 4.5%, p=0.352, respectively, on survival analysis). Independent predictors of all-cause mortality were left ventricular function and creatine clearance (p=0.039, HR 0.92, 95% CI 0.85-0.99 and p=0.013, HR 0.96, 95% CI 0.93-0.99, respectively).

CONCLUSIONS

T2DM did not influence outcomes in CTO patients undergoing PCI, and its presence should not be a limiting factor in deciding on CTO revascularization.

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.

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.

Long-Term Outcomes in Patients With Chronic Total Occlusion

Although a chronic total occlusion (CTO) in the setting of an acute coronary syndrome is associated with greater risk, the prognosis of patients with a CTO and stable coronary artery disease (CAD) remains unknown. This study aimed to investigate adverse event rates in patients with stable CAD with and without a CTO. In 3,597 patients with stable CAD (>50% coronary luminal stenosis) who underwent cardiac catheterization, all-cause mortality, cardiovascular mortality, and the composite major adverse cardiac event (MACE) rates for cardiovascular death, myocardial infarction, and heart failure hospitalization were evaluated. Cox proportional hazards and Fine and Gray subdistribution hazard models were used to compare event-free survival in patient subsets after adjustment for covariates. Event rates were higher in patients with CTOs than in those without CTOs after adjusting for demographic and clinical characteristics (cardiovascular death hazard ratio [HR] 1.29, 95% confidence interval [CI] 1.05 to 1.57, p = 0.012). Patients with CTO revascularization had lower event rates than those of patients without CTO revascularization (cardiovascular death HR 0.43, CI 0.26 to 0.70, p = 0.001). Those with nonrevascularized CTOs were at particularly great risk when compared with those without CTO (cardiovascular death HR 1.52, CI 1.25 to 1.84, p <0.001). Moreover, those with revascularized CTOs had similar event rates to those of patients with CAD without CTOs. Patients with CTO have higher rates of adverse cardiovascular events than those of patients with significant CAD without CTO. This risk is greatest in patients with nonrevascularized CTO.

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.

Use of export thrombus aspiration catheter as a dual lumen catheter for antegrade LAD CTO wiring with side branch

A 50-year-old female patient presented with class III angina for 6 months, positive stress test, and a prior CT angiogram suggestive of 3-vessel disease.

Extraplaque blood withdrawal stenting: A miraculous cure for subintimal hematoma

We report the Extraplaque Blood Withdrawal stenting technique to treat chronic total occlusion percutaneous coronary intervention (CTO PCI)-induced extraplaque hematoma.

Relation Between Calcium-Phosphorus Product and Total Coronary Artery Occlusion in a Nonchronic Kidney Disease Population: A Cross-Sectional Study

Excessive calcium-phosphorus product (Ca-P product) in patients with chronic kidney disease (CKD) is associated with coronary artery calcification and coronary artery disease, but the relation between Ca-P product and coronary artery disease in non-CKD populations has rarely been reported. Therefore, we designed a cross-sectional study to investigate the role of Ca-P product in total coronary artery occlusion (TCAO) in a non-CKD population. We reviewed 983 patients who underwent coronary angiography at Guangyuan Central Hospital from February 2018 to January 2020. Ca-P product (mg2/dl2) was calculated as Ca (mmol/L) × 4 × P (mmol/L) × 3.1 and was analyzed as a continuous and tertiary variable. TCAO was defined as complete occlusion of any coronary artery by coronary angiography (thrombolysis in myocardial infarction flow grade 0). Statistical analysis was performed using univariate and multivariate logistic regression models and restricted cubic splines. Univariate logistic regression analysis showed a statistically significant association between Ca-P product and TCAO (odds ratio [OR] 0.97, 95% confidence interval [CI] 0.95 to 0.99, p <0.001). After stepwise adjustment for covariates, the risk of TCAO was reduced by 40% in the high versus low Ca-P group (OR 0.6, 95% CI 0.38 to 0.95, p = 0.031), and the risk of TCAO was predicted to decrease by 4% (OR 0.96, 95% CI 0.94 to 0.99, p = 0.006) for each unit increase in Ca-P product. Restricted cubic splines showed a nonlinear relation between Ca-P product and TCAO, with a significant decrease in the risk of TCAO after reaching 27.46 (nonlinear p = 0.047). In conclusion, in non-CKD populations, a higher Ca-P product (≥27.46 mg2/dl2) may help avoid TCAO.

Prevalence of Collateral Typology in Coronary Chronic Total Occlusion and Its Impact on Percutaneous Intervention Performance

The presence of collateral channels providing distal blood supply is a distinctive characteristic of chronic total occlusion (CTO) lesions. However, data about the distinct baseline and procedural characteristics of each collateral subset are scarce. Accordingly, we sought to explore the procedural aspects specific for each collateral typology (ipsilateral collaterals [ICs], contralateral collaterals [CCs] or mixed) in CTO-percutaneous coronary intervention (PCI). A retrospective analysis of our CTO-PCI registry was performed to investigate the prevalence, procedural characteristics, and outcomes specific for each CTO-PCI subset, defined according to the inter-arterial connection anatomy. A total of 209 cases were included. Of the included cases, 45 (22%) and 92 (44%) patients displayed solely IC or CC, respectively, whereas in 72 (34%) both IC and CC were present (mixed). The procedural success rate was high (91.1%) and comparable among the different groups, despite greater lesion complexity in the CC group. The most frequent target vessel was the left circumflex in the IC group (51% of cases) and the right coronary artery in the CC (63%) and mixed (57%) groups. Among the IC cases, 42% showed a poor collateral connection function (2% and 10% for the CC and mixed group, respectively), and 46% showed a suboptimal collateral recipient artery filling (21% and 20% for the CC and mixed group, respectively). Most of the IC cases were performed using a single access (96%). In conclusion, the success and complication rates were comparable among the collateral typology groups, irrespective of the differences in the baseline and procedural characteristics. Phenotyping CTO as hereby proposed might be helpful for targeted procedural considerations.

Accurate Prediction of Retrograde Collateral Channel Crossing in Coronary Artery Chronic Total Occlusion Intervention

Successful collateral channel (CC) crossing is an essential step in retrograde chronic total occlusion (CTO) percutaneous coronary interventions (PCIs). We previously developed a dedicated CC score based on CC size and tortuosity to facilitate target CC selection. Validation and comparison to other scoring systems were lacking. Thus, the aims of this study were to (1) validate the CC score in a larger independent cohort, and (2) compare its accuracy and clinical usefulness with the J-channel score. All coronary CTO PCIs attempted by experienced high-volume operators from January 2017 to December 2021 were enrolled. The CC and J-channel scores were calculated for all attempted CCs with bi-plane high-resolution cine angiography images. CC crossing success was defined as guidewire reaching the distal true lumen retrogradely. In total, 502 patients who received CTO PCI were included. The retrograde approach was utilized in 244 target CTOs, and a total of 329 CCs were attempted. The overall CC crossing rate was 67.8% (223 of 329) and final technical success rate 92.2% (225 of 244). The average CC score was 2.0 and average J-channel score was 0.71. The sensitivity and specificity of successful CC crossing with the CC score ≥2 were 81.2%, and 84.0%, respectively. Comparison between the CC score (area under the curve 0.87; 95% confidence interval 0.83 to 0.90) and the J-channel score (area under the curve 0.61, 95% confidence interval 0.55 to 0.67) demonstrated superior predictive performance of the CC score (p <0.001). The CC score was an easy-to-use and accurate tool for the prediction of successful CC crossing in retrograde CTO PCI. The CC score can help operators select the ideal target CC, thereby facilitating final procedural success.

Acute coronary occlusion and percutaneous coronary intervention after out-of-hospital cardiac arrest

OBJECTIVES

Early coronary angiography (CAG) has been recommended in selected patients following out-of-hospital-cardiac-arrest (OHCA). We aimed to identify clinical features associated with acute coronary occlusion (ACO) and evaluate the associations between ACO, successful percutaneous coronary intervention (PCI) and outcomes in this population.

METHODS

We included comatose OHCA patients treated with targeted temperature management (TTM) between December 2005 and September 2016 who underwent early CAG within 24 hours. The co-primary outcomes were all-cause 30-day mortality and good neurological outcome (modified Rankin Score [mRS] ≤2) at hospital discharge.

RESULTS

Among 155 patients (93% shockable arrest rhythm, 55% with ST elevation), 133 (86%) had coronary artery stenosis ≥50% and 65 (42%) had ACO. ST elevation (sensitivity 74%, specificity 59%, OR 4.0, 95% CI 2.0-8.1) and elevated first troponin (sensitivity 88%, specificity 26%, OR 2.5, 95% CI 1.1-6.1) had limited sensitivity and specificity for ACO. Unadjusted 30-day mortality did not differ significantly by coronary disease severity or ACO. Successful PCI was associated with a lower risk of 30-day mortality (adjusted HR 0.5, 95% CI 0.2-0.9, P=.03), especially among patients with ACO (adjusted HR 0.4, 95% CI 0.1-0.9, P=0.03). After adjustment, ACO and PCI were not associated with the probability of good neurological outcome.

CONCLUSIONS

In this select cohort of resuscitated OHCA patients undergoing CAG, unstable coronary disease is highly prevalent and successful PCI was associated with a higher probability of 30-day survival, especially among those with ACO. Neither ACO nor successful PCI were independently associated with good neurological outcome.

Uric acid to high-density lipoprotein cholesterol ratio predicts adverse cardiovascular events in patients with coronary chronic total occlusion

BACKGROUND AND AIMS

Uric acid to high-density lipoprotein cholesterol ratio (UHR) is a novel index of metabolism and inflammation proposed by recent studies. The prognostic value of UHR is undetermined in patients with coronary chronic total occlusion (CTO). The aim of this study was to investigate the association of UHR with adverse cardiovascular events in patients with CTO.

METHODS AND RESULTS

In this retrospective cohort study, we enrolled 566 patients with CTO lesion in our hospital from January 2016 to December 2019. Patients were divided into three groups based on UHR level. The primary endpoint was major adverse cardiovascular event (MACE), defined as a combination of death, non-fatal MI, target vessel revascularization (TVR), and non-fatal stroke. The median follow-up time of this study was 43 months. During the follow-up, 107 (18.9%) MACEs were recorded. Kaplan-Meier survival plots show the cumulative incidence of MACE-free decreased across tertile of UHR (log-rank test, p < 0.001). In the fully adjusted model, the Hazard ratio (95% CI) of MACE was 2.16 (1.17-3.99) in tertile 3 and 2.01 (1.62-2.49) for per SD increase in UHR.

CONCLUSION

Elevated UHR predicts an increasing risk of MACE in patients with CTO. UHR is a simple and reliable indicator for risk stratification and early intervention in CTO patients.

Interventions in chronic total occlusions with bifurcation lesions: incidence, treatment, and in-hospital outcome

INTRODUCTION AND OBJECTIVES

Coronary chronic total occlusions (CTO) involving bifurcation lesions are a challenging lesion subset that is understudied in the literature. This study analyzed the incidence, procedural strategy, in-hospital outcomes and complications of percutaneous coronary interventions (PCI) for bifurcation-CTO (BIF-CTO).

METHODS

We assessed data from 607 consecutive CTO patients treated at the Institut Cardiovasculaire Paris Sud (ICPS), Massy, France between January 2015 and February 2020. Procedural strategy, in-hospital outcomes and complication rates were compared between 2 patient subgroups: BIF-CTO (n=245=and non-BIF-CTO (n=362).

RESULTS

The mean patient age was 63.2±10.6 years; 79.6% were men. Bifurcation lesions were involved in 40.4% of the procedures. Overall lesion complexity was high (mean J-CTO score 2.30±1.16, mean PROGRESS-CTO score 1.37±0.94). The preferred bifurcation treatment strategy was a provisional approach (93.5%). BIF-CTO patients presented with higher lesion complexity, as assessed by J-CTO score (2.42±1.02 vs 2.21±1.23 in the non-BIF-CTO patients, P=.025) and PROGRESS-CTO score (1.60±0.95 vs 1.22±0.90 in the non-BIF-CTO patients, P<.001). Procedural success was 78.9% and was not affected by the presence of bifurcation lesions (80.4% in the BIF-CTO group, 77.8% in the non-BIF-CTO-CTO group, P=.447) or the bifurcation site (proximal BIF-CTO 76.9%, mid-BIF-CTO 83.8%, distal BIF-CTO 85%, P=.204). Complication rates were similar in BIF-CTO and non-BIF-CTO.

CONCLUSIONS

The incidence of bifurcation lesions is high in contemporary CTO PCI. Patients with BIF-CTO present with higher lesion complexity, with no impact on procedural success or complication rates when the predominant strategy is provisional stenting.

Use of the Carlino Technique in Chronic Total Occlusion Percutaneous Coronary Intervention

We examined the outcomes of the Carlino technique in chronic total occlusion (CTO) percutaneous coronary interventions (PCIs). We analyzed the baseline clinical and angiographic characteristics and outcomes of 128 CTO PCIs that included the Carlino technique at 22 US and no-US centers between 2016 and 2023. The Carlino technique was used in 128 (2.8%) of 4,508 cases that used anterograde dissection and reentry (78.9%) or the retrograde approach (21.1%) during the study period, and it increased steadily over time (from 0.0% in 2016 to 8.3% in 2023). The mean patient age was 65.6 ± 9.7 years, and 88.7% of the patients were men with high prevalence of hypertension (89.1%) and dyslipidemia (80.2%). The Carlino technique was more commonly used in cases with moderate to severe calcification (77.2% vs 55.5%, p <0.001) with higher J-CTO (3.3 ± 0.9 vs 3.0 ± 1.1, p = 0.007), Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS-CTO) (1.7 ± 1.0 vs 1.4 ± 1.0, p = 0.001), PROGRESS-CTO Mortality (2.6 ± 0.9 vs 2.0 ± 0.9, p = 0.013) and PROGRESS-CTO Perforation (3.7 ± 1.1 vs 3.5 ± 1.0, p = 0.029) scores. Carlino cases had longer procedure and fluoroscopy time, and higher contrast volume and radiation dose. Carlino cases had lower technical (65.6% vs 78.5%, p <0.001) and procedural (63.3% vs 76.3%, p <0.001) success, similar major adverse cardiac events (6.2% vs 3.2%, p = 0.101) and higher incidence of pericardiocentesis (3.9% vs 1.3%, p = 0.042), perforation (18.0% vs 8.9%, p = 0.001) and contrast-induced acute kidney injury (2.3% vs 0.4%, p = 0.012). The Carlino technique was associated with higher procedural success when used for retrograde crossing (81.5% vs 58.4%, p = 0.047). The Carlino technique is increasingly being used in CTO PCI especially for higher complexity lesions.

Effect of myocardial scar size on the risk of ventricular arrhythmias in patients with chronic total coronary occlusion

BACKGROUND

The presence of an untreated chronic total coronary occlusion (CTO) is associated with a higher risk of ventricular arrhythmias (VAs). This increased risk may be modulated by the presence of an existing scar.

OBJECTIVES

To evaluate whether scar size is associated with VA in patients with an implantable cardioverter-defibrillator (ICD) and a CTO.

METHODS

In this retrospective study we included patients with a CTO that received an ICD between 2005 and 2015. Scar size was estimated using the Selvester QRS score on a baseline 12‑lead ECG. The primary endpoint was any appropriate ICD therapy.

RESULTS

Our study population comprised 148 CTO patients with a median scar size at baseline of 18% (IQR, 9-27%). Patients with a scar size ≥18% more often had a CTO located in the left anterior descending artery and a higher proportion of poor left ventricular function (<35%) and infarct-related CTO compared to patients with a smaller scar size (<18%). During a median follow-up of 35 months (interquartile range [IQR], 8-60 months), 42 patients (28%) received appropriate ICD therapy. The cumulative 5-year event rate was higher in the patients with a large scar in comparison to those with a smaller or no scar (36% versus 19%, P = 0.04). Multivariable Cox regression analysis demonstrated that large scar and diabetes mellitus were independent factors associated with appropriate ICD therapy.

CONCLUSION

In ICD recipients with an untreated CTO, a larger scar is an independent factor associated with an increased risk of VA.

Impact of calcium on the procedural techniques and outcomes of chronic total occlusion percutaneous coronary intervention

BACKGROUND

Coronary calcification is common and increases the difficulty of chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

METHODS

We examined the impact of calcium on procedural outcomes of 13,079 CTO PCIs performed in 12,799 patients at 46 US and non-US centers between 2012 and 2023.

RESULTS

Moderate or severe calcification was present in 46.6% of CTO lesions. Patients whose lesions were calcified were older and more likely to have had prior coronary artery bypass graft surgery. Calcified lesions were more complex with higher J-CTO score (3.0 ± 1.1 vs. 1.9 ± 1.2; p < 0.001) and lower technical (83.0% vs. 89.9%; p < 0.001) and procedural (81.0% vs. 89.1%; p < 0.001) success rates compared with mildly calcified or non-calcified CTO lesions. The retrograde approach was more commonly used among cases with moderate/severe calcification (40.3% vs. 23.5%; p < 0.001). Balloon angioplasty (76.6%) was the most common lesion preparation technique for calcified lesions, followed by rotational atherectomy (7.3%), laser atherectomy (3.4%) and, intravascular lithotripsy (3.4%). The incidence of major adverse cardiovascular events (MACE) was higher in cases with moderate or severe calcification (3.0% vs. 1.2%; p < 0.001), as was the incidence of perforation (6.5% vs. 3.4%; p < 0.001). On multivariable analysis, the presence of moderate/severe calcification was independently associated with lower technical success (odds ratio, OR = 0.73, 95% CI: 0.63-0.84) and higher MACE (OR = 2.33, 95% CI: 1.66-3.27).

CONCLUSIONS

Moderate/severe calcification was present in nearly half of CTO lesions, and was associated with higher utilization of the retrograde approach, lower technical and procedural success rates, and higher incidence of in-hospital MACE.

Outcomes of chronic total occlusion percutaneous coronary intervention from the RAIAN (RAjaie - Iran) registry

OBJECTIVE

While most of the evidence in CTO interventions emerge from Western and Japanese studies, few data have been published up today from the Middle East. Objective of this study was to evaluate technical success rates and clinical outcomes of an Iranian population undergoing CTO PCI in a tertiary referral hospital. Moreover, we sought to evaluate the efficacy of our CTO teaching program.

METHODS

This is a retrospective single-center cohort study including 790 patients who underwent CTO PCI performed by operators with different volumes of CTOs PCI performed per year. According to PCI result, all patients have been divided into successful (n = 555, 70.3 %) and unsuccessful (n = 235, 29.7 %) groups. Study endpoints were Major Adverse Cardiovascular Events and Health Status Improvement evaluated using the Seattle Angina Questionnaire at one year.

RESULTS

A global success rate of 70 % for antegrade and 80 % for retrograde approach was shown despite the lack of some CTO-dedicated devices. During the enrollment period, the success rate increased significantly among operators with a lower number of CTO procedures per year. One-year MACE rate was similar in both successful and unsuccessful groups (13.5 % in successful and 10.6 % in unsuccessful group, p = 0.173). One year patients' health status improved significantly only in successful group.

CONCLUSIONS

No significant differences of in-hospital and one-year MACE were found between the successful and unsuccessful groups. Angina symptoms and quality of life significantly improved after successful CTO PCI. The RAIAN registry confirmed the importance of operator expertise for CTO PCI success.

Impact of coronary collaterals on the outcomes of chronic total occlusion percutaneous coronary intervention

This study aims to evaluate the impact that the presence of interventional collaterals has on the outcomes of CTO PCI. We examined the clinical and angiographic characteristics and procedural outcomes of 11 205 patients who underwent 11 444 CTO PCIs at 45 US and non-US centers between 2012 and 2023.

Contemporary In-Hospital Outcomes of Chronic Total Occlusion Percutaneous Coronary Interventions: Insights from the MENATA (Middle East, North Africa, Turkey, and Asia) Chapter of the PROGRESS-CTO Registry

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has been rapidly evolving in different parts of the world. We examined the clinical and angiographic characteristics and procedural outcomes of 1,079 consecutive CTO PCIs performed in 1,063 patients at 10 centers in the Middle East, North Africa, Turkey, and Asia regions between 2018 and 2022. The mean age was 61 ± 10 years and 82% of the patients were men. The prevalence of diabetes (49%) and previous PCI (50%) was high. The most common target vessel was the right coronary artery (51%), followed by the left anterior descending artery (33%) and the circumflex artery (15%). The mean Japanese CTO score was 2.1 ± 1.2 and mean PROGRESS-CTO (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention) score was 1.2 ± 1.0. The technical and procedural success rates were high (91% and 90%, respectively) with a low incidence (1.6%) of in-hospital major adverse cardiac events. The incidence of perforation was 4.6% (n = 50): guidewire exit was the most common mechanism of perforation (48%) and 14 patients required pericardiocentesis (28%). Antegrade wire escalation was the most common crossing strategy used (91%), followed by retrograde approach (24%) and antegrade dissection and re-entry (12%). Median contrast volume, air kerma radiation dose, and fluoroscopy time were 300 (200 to 400) ml, 3.7 (2.0 to 6.3) Gy, and 40 (25 to 65) minutes, respectively. In conclusion, high success and acceptable complication rates are currently achieved at experienced centers in the Middle East, North Africa, Turkey, and Asia regions using a combination of crossing strategies.

Trends and Inhospital Outcomes of Intravascular Imaging on Single-Vessel Coronary Chronic Total Occlusion Treated With Percutaneous Coronary Intervention

Intravascular imaging (IVI), including intravascular ultrasound (IVUS) and optical coherence tomography (OCT), improves outcomes of percutaneous coronary intervention (PCI) for chronic total occlusions (CTOs). We sought to quantify temporal trends in the uptake of IVI for CTO-PCI in the United States. We identified adults who underwent single-vessel PCI for CTO between 2008 and 2020. We quantified yearly trends in the number of IVUS-guided and OCT-guided single-vessel CTO-PCIs by Cochran-Armitage and linear regression tests. We also examined the rates of inhospital mortality and other prespecified inhospital outcomes in patients who underwent CTO-PCIs with and without IVI, using logistic regression. Our study included a total of 151,998 PCIs on single-vessel CTOs, with the absolute number of CTO-PCIs decreasing from 12,345 in 2008 to 8,525 in 2020 (p trend <0.001). IVUS use has increased dramatically from 6% in 2008 to 18% in 2020 for single-vessel CTO-PCIs (p trend <0.001). Rates of OCT use have increased as well, from 0% in 2008 to 7% in 2020 (p trend <0.001). There was no difference in inhospital mortality between patients who underwent CTO-PCI with and without IVI (p logistic = 0.60). In the largest national analysis of single-vessel CTO-PCI trends to date, we found that the use of IVUS has increased substantially accompanied by a similar but lesser increase in the use of OCT. There were no differences in rates of inhospital mortality between patients who underwent single-vessel CTO-PCIs with and without IVI.

Ping-pong guide catheter technique for facilitating antegrade crossing of a chronic total occlusion

A 60-year-old man was referred for percutaneous coronary intervention of a proximal left circumflex (Cx) chronic total occlusion (CTO) with distal filling via epicardial collaterals from the left anterior descending (LAD) artery.

Outcomes of Chronic Total Occlusion Percutaneous Coronary Interventions in Patients With Previous Coronary Artery Bypass Graft Surgery

The outcomes of chronic total occlusion (CTO) percutaneous coronary interventions (PCIs) in patients with previous coronary artery bypass graft (CABG) surgery have received limited study. We examined the baseline characteristics and outcomes of CTO PCIs performed at 47 United States and non-United States centers between 2012 and 2023. Of the 12,164 patients who underwent CTO PCI during the study period, 3,475 (29%) had previous CABG. Previous CABG patients were older, more likely to be men, and had more comorbidities and lower left ventricular ejection fraction and estimated glomerular filtration rate. Their CTOs were more likely to have moderate/severe calcification and proximal tortuosity, proximal cap ambiguity, longer lesion length, and higher Japanese CTO scores. The first and final successful crossing strategy was more likely to be retrograde. Previous CABG patients had lower technical (82.1% vs 88.2%, p <0.001) and procedural (80.8% vs 86.8%, p <0.001) success, higher in-hospital mortality (0.8% vs 0.3%, p <0.001), acute myocardial infarction (0.9% vs 0.5%, p = 0.007) and perforation (7.0% vs 4.2%, p <0.001) but lower incidence of pericardial tamponade and pericardiocentesis (0.1% vs 1.3%, p <0.001). At 2-year follow-up, the incidence of major adverse cardiac events, repeat PCI and acute coronary syndrome was significantly higher in previous CABG patients, whereas all-cause mortality was similar. In conclusion, patients with previous CABG who underwent CTO PCI had more complex clinical and angiographic characteristics and lower success rate, higher perioperative mortality, and myocardial infarction but lower tamponade, and higher incidence of major adverse cardiac events with similar all-cause mortality during follow-up.

Machine learning-based analysis of risk factors for chronic total occlusion in an Asian population

OBJECTIVES

Chronic total occlusion (CTO) is a form of coronary artery disease (CAD) requiring percutaneous coronary intervention. There has been minimal research regarding CTO-specific risk factors and predictive models. We developed machine learning predictive models based on clinical characteristics to identify patients with CTO before coronary angiography.

METHODS

Data from 1473 patients with CAD, including 317 patients with and 1156 patients without CTO, were retrospectively analyzed. Partial least squares discriminant analysis (PLS-DA), random forest (RF), and support vector machine (SVM) models were used to identify CTO-specific risk factors and predict CTO development. Receiver operating characteristic (ROC) curve analysis was performed for model validation.

RESULTS

For CTO prediction, the PLS-DA model included 10 variables; the ROC value was 0.706. The RF model included 42 variables; the ROC value was 0.702. The SVM model included 20 variables; the ROC value was 0.696. DeLong's test showed no difference among the three models. Four variables were present in all models: sex, neutrophil percentage, creatinine, and brain natriuretic peptide (BNP).

CONCLUSIONS

Validation of machine learning prediction models for CTO revealed that the PLS-DA model had the best prediction performance. Sex, neutrophil percentage, creatinine, and BNP may be important risk factors for CTO development.

The safety and feasibility of live-stream proctoring for CTO procedures

OBJECTIVE

To assess the technical feasibility of a new method of educational training, based on audio-video (AV) communication between an interventional cardiologist and the cath lab staff members in one location and a remote expert proctor.

METHODS

Overall, 9 patients underwent a percutaneous coronary intervention (PCI) targeting a chronic total occlusion (CTO) between June 2021 and January 2022 at a single Belgian center using the virtual proctoring approach. For this assessment, the strategic planning of the CTO PCI and all the decisions throughout the intervention were the responsibility of the proctor. The operator was guided via an AV link, by the proctor throughout the procedure.

RESULTS

The operator performed each procedural step, guided by the remote proctor, who had continuous access to all relevant interventional details. No major adverse cardiac events (MACE) occurred during the index hospitalization or within 6 months follow-up.

CONCLUSIONS

A new method of virtual proctoring based on live AV communication is feasible, even in the case of highly complex CTO PCI procedures. This strategy also appears safe and may provide the patient the benefit of incremental expertise. This approach is facilitated by advances in AV communication and allows physicians to share expertise irrespective of location. It could increase global interaction between colleagues and facilitate sharing of knowledge, which are both key aspects in the development of CTO PCI. This preliminary experience could serve as a basis for future large studies to study the potential role and benefits of virtual proctoring for complex CTO PCI procedures.

Occlusion of the infarct-related coronary artery presenting as acute coronary syndrome with and without ST-elevation: impact of inflammation and outcomes in a real-world prospective cohort

BACKGROUND

Patients with ST-segment elevation typically feature total coronary occlusion (TCO) of the infarct-related artery (IRA) on angiography, which may result in worse outcomes. Yet, relying solely on electrocardiogram (ECG) findings may be misleading and those presenting with non-ST-segment elevation acute coronary syndromes (NSTE-ACSs) may have TCO as well. Herein, we aimed to delineate clinical characteristics and outcomes of patients with ACS stratified by IRA location.

METHODS

A total of 4787 ACS patients were prospectively recruited between 2009 and 2017 in SPUM-ACS (ClinicalTrials.gov Identifier: NCT01000701). The primary endpoint was major adverse cardiovascular events (MACEs), a composite of all-cause death, non-fatal myocardial infarction and non-fatal stroke at 1 year. Multivariable-adjusted survival models were fitted using backward selection.

RESULTS

A total of 4412 ACS patients were included in this analysis, 56.0% (n = 2469) ST-elevation myocardial infarction (STEMI) and 44.0% (n = 1943) NSTE-ACS. The IRA was the right coronary artery (RCA) in 33.9% (n = 1494), the left-anterior descending coronary artery (LAD) in 45.6% (n = 2013), and the left circumflex (LCx) in 20.5% (n = 905) patients. In STEMI patients, TCO (defined as TIMI 0 flow at angiography) was observed in 55% of cases with LAD, in 63% with RCA, and in 55% with LCx. In those presenting with NSTE-ACS, TCO was more frequent in those with LCx and RCA as compared to the LAD (27 and 24%, respectively, vs. 9%, P < 0.001). Among patients with NSTE-ACS, occlusion of the LCx was associated with an increased risk of MACE during 1 year after the index ACS (fully adjusted hazard ratio 1.68, 95% confidence interval 1.10-2.59, P = 0.02; reference: RCA and LAD). Features of patients with NSTE-ACS associated with TCO of the IRA included elevated lymphocyte and neutrophil counts, higher levels of high-sensitivity C reactive protein (hs-CRP) and high-sensitivity cardiac troponin T, lower eGFR, and notably a negative history of MI.

CONCLUSION

In NSTE-ACS, both LCx and RCA involvement was associated with TCO at angiography despite the absence of ST-segment elevation. Involvement of the LCx, but not the LAD or RCA, as the IRA represented an independent predictor of MACE during 1-year follow-up. Hs-CRP, lymphocyte, and neutrophil counts were independent predictors of total IRA occlusion, suggesting a possible role of systemic inflammation in the detection of TCO irrespective of ECG presentation.

Development of a Novel Score to Predict Urgent Mechanical Circulatory Support in Chronic Total Occlusion Percutaneous Coronary Intervention

Estimating the likelihood of urgent mechanical circulatory support (MCS) can facilitate procedural planning and clinical decision-making in chronic total occlusion (CTO) percutaneous coronary intervention (PCI). We analyzed 2,784 CTO PCIs performed between 2012 and 2021 at 12 centers. The variable importance was estimated by a bootstrap applying a random forest algorithm to a propensity-matched sample (a ratio of 1:5 matching cases with controls on center). The identified variables were used to predict the risk of urgent MCS. The performance of the risk model was assessed in-sample and on 2,411 out-of-sample procedures that did not require urgent MCS. Urgent MCS was used in 62 (2.2%) of cases. Patients who required urgent MCS were older (70 [63 to 77] vs 66 [58 to 73] years, p = 0.003) compared with those who did not require urgent MCS. Technical (68% vs 87%, p <0.001) and procedural success (40% vs 85%, p <0.001) was lower in the urgent MCS group compared with cases that did not require urgent MCS. The risk model for urgent MCS use included retrograde crossing strategy, left ventricular ejection fraction, and lesion length. The resulting model demonstrated good calibration and discriminatory capacity with the area under the curve (95% confidence interval) of 0.79 (0.73 to 0.86) and specificity and sensitivity of 86% and 52%, respectively. In the out-of-sample set, the specificity of the model was 87%. The Prospective Global Registry for the Study of Chronic Total Occlusion Intervention CTO MCS score can help estimate the risk of urgent MCS use during CTO PCI.

Alternative (Transulnar or Distal Radial) Arterial Access for Chronic Total Occlusion Percutaneous Coronary Intervention (Subanalysis from the Minimalistic Hybrid Approach Algorithm Registry)

The transradial approach (TRA) has become the primary choice for percutaneous coronary intervention (PCI); however, it may not be always feasible because of clinical and/or technical challenges. Alternative forearm accesses, such as transulnar approach (TUA) and distal radial approach (dTRA) may allow maintaining a wrist approach for the procedure, avoiding the femoral artery. This issue is particularly relevant in patients who underwent multiple revascularizations, such as those with chronic total occlusion (CTO) lesions. This study aimed to evaluate whether the use of TUA and/or dTRA is comparable with TRA in CTO PCI using a minimalistic hybrid approach algorithm, which limits the number of accesses used to minimize vascular access complications. Patients with CTO PCI treated solely through a fully alternative approach (TUA and/or dTRA) were compared with those treated solely through a standard TRA approach. The primary efficacy end point was procedural success, whereas the primary safety end point was the composite of major adverse cardiac and cerebral events and vascular complications. Of 201 CTO PCIs attempted, 154 procedures were considered for analysis (standard, n = 104, alternative, n = 50). Alternative and standard groups demonstrated comparable rates of both procedural success (92% vs 94.2%, p = 0.70) and primary safety end point (4.8% vs 6.0%, p = 0.70). Of interest, 7 French guiding catheters were more frequently used in the alternative group (44% vs 26%, p = 0.028). In conclusion, CTO PCI after minimalistic hybrid approach by way of alternative forearm vascular accesses (dTRA and/or TUA) is feasible and safe to perform, compared with CTO PCI by way of standard TRA.

Frequency and outcomes of ad hoc chronic total occlusion percutaneous coronary intervention: insights from the progress-cto registry

BACKGROUND

Although discouraged, ad hoc chronic total occlusion (CTO) percutaneous coronary intervention (PCI) is occasionally performed.

METHODS

We examined the clinical, angiographic characteristics, and procedural outcomes of patients who underwent ad hoc CTO PCI in the Prospective Global Registry for the Study of CTO Intervention (PROGRESS-CTO, NCT02061436).

RESULTS

Of the 10,998 patients included in the registry, 899 (8.2%) underwent ad hoc CTO PCI. The incidence of ad hoc CTO PCI decreased from 18% in 2016 to 3% in 2022. Ad hoc CTO PCI patients had a lower prevalence of comorbidities and less complex angiographic characteristics demonstrated by lower J-CTO score (1.9±1.2 vs 2.4±1.3, P < .001). In these patients, PROGRESS-CTO major adverse cardiovascular events (MACE) (1.9±1.4 vs 2.5±1.7), mortality (1.2±1.0 vs 1.6±1.1), and perforation (1.5±1.2±2.2 vs 1.5) scores were lower (P < .001). Technical success was similar between the groups (86%). MACE were lower in the ad hoc CTO PCI group (.8% vs 2.0%, P=.009). Ad hoc CTO PCI was not associated with MACE after adjusting for potential confounders, odds ratio: .69 (95% confidence interval, .30-1.57). In patients with higher J-CTO scores, planned CTO PCI was associated with higher technical success (P < .001).

CONCLUSION

Approximately 8% of CTO PCI procedures are performed ad hoc, usually in less complex lesions and patients with lower complication risk. While ad hoc CTO PCI might be appropriate for carefully selected cases, a staged approach is recommended for most CTO PCI.

Health Status Outcomes in Older Adults Undergoing Chronic Total Occlusion Percutaneous Coronary Intervention

Background Although chronic total occlusions (CTOs) are common in older adults, they are less likely to be offered CTO percutaneous coronary intervention for angina relief than younger adults. The health status impact of CTO percutaneous coronary intervention in adults aged ≥75 years has not been studied. We sought to compare technical success rates and angina-related health status outcomes at 12 months between adults aged ≥75 and <75 years in the OPEN-CTO (Outcomes, Patient Health Status, and Efficiency in Chronic Total Occlusion) registry. Methods and Results Angina-related health status was assessed with the Seattle Angina Questionnaire (score range 0-100, higher scores denote less angina). Technical success rates were compared using hierarchical modified Poisson regression, and 12-month health status was compared using hierarchical multivariable linear regression between adults aged ≥75 and <75 years. Among 1000 participants, 19.8% were ≥75 years with a mean age of 79.5±4.1 years. Age ≥75 years was associated with a lower likelihood of technical success (adjusted risk ratio=0.92 [95% CI, 0.86-0.99; P=0.02]) and numerically higher rates of in-hospital major adverse cardiovascular events (9.1% versus 5.9%, P=0.10). There was no difference in Seattle Angina Questionnaire Summary Score at 12 months between adults aged ≥75 and <75 years (adjusted difference=0.9 [95% CI, -1.4 to 3.1; P=0.44]). Conclusions Despite modestly lower success rates and higher complication rates, adults aged ≥75 years experienced angina-related health status benefits after CTO-percutaneous coronary intervention that were similar in magnitude to adults aged <75 years. CTO percutaneous coronary intervention should not be withheld based on age alone in otherwise appropriate candidates.

Procedural outcomes of chronic total occlusion percutaneous coronary interventions in patients with acute kidney injury

BACKGROUND

The prognostic impact of contrast-associated acute kidney injury (CA-AKI) in patients undergoing chronic total occlusion (CTO) percutaneous coronary intervention (PCI) remains underestimated.

METHODS

We examined 2707 consecutive procedures performed in a referral CTO center between 2015 and 2019. CA-AKI was defined as an increase in serum creatinine ≥ 0.3 mg/dL or ≥ 50% within 48 h post-PCI. Primary endpoints were in-hospital major adverse cardiac and cerebrovascular events (MACCE, composite of all-cause death, myocardial infarction, target vessel revascularization, stroke) and at one year of follow-up.

RESULTS

The overall incidence of CA-AKI was 11.5%. Technical success was comparable (87.2% vs. 90.5%, p = 0.056) whereas procedural success was lower in the CA-AKI group (84.3% vs. 89.7%, p = 0.004). Overall in-hospital MACCE was 1.3%, and it was similar in patients with and without CA-AKI (1.6% vs. 1.3%, p = 0.655); however, the rate of pericardial tamponade requiring pericardiocentesis was significantly higher in patients with CA-AKI (2.2% vs. 0.5%, p = 0.001). In multivariate analysis, CA-AKI was not independently associated with higher risk for in-hospital MACCE (adjusted odds ratio [OR] 1.34, 95% confidence intervals [CI] 0.45-3.19, p = 0.563). At a median follow-up time of 14 months (interquartile range [IQR], 11 to 35 months), one-year MACCE was significantly higher in patients with vs. without CA-AKI (20.8% vs. 12.8%, p < 0.001), and CA-AKI increased the risk for one-year MACCE (adjusted hazard ratio [HR] 1.46, 95% CI 1.07-1.95, p = 0.017) following CTO PCI.

CONCLUSIONS

CA-AKI in patients undergoing CTO PCI occurs in approximately one out of 10 patients. Our study highlights that patients developing CA-AKI are at increased risk for long-term MACCE.

A comprehensive and easy-to-use ECG algorithm to predict the coronary occlusion site in ST-segment elevation myocardial infarction

BACKGROUND

Several electrocardiogram (ECG) criteria have been proposed to predict the location of the culprit occlusion in specific subsets of patients presenting with ST-segment elevation myocardial infarction (STEMI). The aim of this study was to develop, through an independent validation of currently available criteria, a comprehensive and easy-to-use ECG algorithm, and to test its diagnostic performance in real-world clinical practice.

METHODS

We analyzed ECG and angiographic data from 419 consecutive STEMI patients submitted to primary percutaneous coronary intervention over a one-year period, dividing the overall population into derivation (314 patients) and validation (105 patients) cohorts. In the derivation cohort, we tested >60 previously published ECG criteria, using the decision-tree analysis to develop the algorithm that would best predict the infarct-related artery (IRA) and its occlusion level. We further assessed the new algorithm diagnostic performance in the validation cohort.

RESULTS

In the derivation cohort, the algorithm correctly predicted the IRA in 88% of cases and both the IRA and its occlusion level (proximal vs mid-distal) in 71% of cases. When applied to the validation cohort, the algorithm resulted in 88% and 67% diagnostic accuracies, respectively. In a real-world comparative test, the algorithm performed significantly better than expert physicians in identifying the site of the culprit occlusion (P = .026 vs best cardiologist and P < .001 vs best emergency medicine doctor).

CONCLUSIONS

Derived from an extensive literature review, this comprehensive and easy-to-use ECG algorithm can accurately predict the IRA and its occlusion level in all-comers STEMI patients.

Association of Annual Operator Volume With the Outcomes of Chronic Total Occlusion Percutaneous Coronary Intervention

OBJECTIVES

There are limited data on the association of operator volume with the outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

METHODS

We analyzed the association between operator volume and procedural outcomes of 7035 CTO-PCIs performed between 2012 and February 2021 at 30 centers.

RESULTS

The study population was divided into 3 groups based on annual operator CTO-PCI volume: low-volume operators (LVO: &lt;30 cases/year; 39.7% of the cases); medium-volume operators (MVO: 30-60 cases/year; 25.7% of the cases); and high-volume operators (HVO: &gt;60 cases/ year; 34.6% of the cases). Mean patient age was 64.4 ± 10 years and 82% were men. Cases performed by HVOs were more complex, with higher J-CTO score compared with cases performed by MVOs and LVOs (2.72 ± 1.27 vs 2.39 ± 1.19 vs 2.12 ± 1.27, respectively; P&lt;.001). Moderate/severe proximal vessel tortuosity (35% vs 23% vs 20%; P&lt;.001) and proximal cap ambiguity (44% vs 34% vs 32%; P&lt;.001) was also more common in the HVO group. Cases performed by HVOs had higher technical success rates (87.9% vs 86.9% vs 82.6%; P&lt;.001), but also higher rates of periprocedural major cardiac adverse events compared with MVOs and LVOs (3.08% vs 2.71% vs 1.50%; P&lt;.01). On multivariable analyses, HVOs and MVOs were associated with higher technical success.

CONCLUSIONS

In a contemporary, multicenter registry, 40% of CTO-PCI cases are performed by LVOs performing &lt;30 cases per year. Cases performed by HVOs were associated with higher technical and procedural success, but also higher periprocedural major complication rates, potentially due to higher lesion complexity.

Primary vs Secondary Retrograde Approach in Chronic Total Occlusion Percutaneous Coronary Interventions

BACKGROUND

The retrograde approach to coronary chronic total occlusions (CTOs) can be used as the initial crossing strategy (primary retrograde) or after failure of antegrade crossing attempts (secondary retrograde).

METHODS

We compared baseline clinical and angiographic characteristics and procedural outcomes of primary vs secondary retrograde crossing for CTO percutaneous coronary intervention (PCI) among 2789 procedures performed at 34 centers between 2012 and 2021.

RESULTS

Retrograde CTO-PCI was performed as the primary crossing strategy in 1086 cases (38.9%) and as a secondary approach in 1703 cases (61.1%). Patients in the primary group had slightly lower left ventricular ejection fraction (49.1% vs 50.4%; P=.02), were more likely to have had prior coronary artery bypass graft surgery (52.9% vs 38.4%; P&lt;.001), and had higher J-CTO (3.31 ± 0.98 vs 2.99 ± 1.09; P&lt;.001) and PROGRESS-CTO scores (1.47 ± 0.92 vs 1.29 ± 0.99; P&lt;.001). Technical (81.4% vs 77.3%; P=.01) and procedural success rates (78.6% vs 74.1%; P&lt;.01) were higher in the primary retrograde group, with no difference between in-hospital major adverse event rates (4.3% vs 4.0%; P=.66). Contrast volume (250 mL [interquartile range (IQR), 176-347] vs 270 mL [IQR, 190-367]; P&lt;.001) and procedure time (175 minutes [IQR, 127-233] vs 180 minutes [IQR, 142-236]; P&lt;.001) were lower in the primary group.

CONCLUSIONS

Use of retrograde approach as the primary crossing strategy is associated with higher rates of technical and procedural success and similar rates of in-hospital major adverse cardiac events compared with secondary retrograde CTO-PCI.

The Impact of a Dedicated Chronic Total Occlusion PCI Program on Heart Team Decision Making

BACKGROUND

Guidelines endorse a heart team (HT) approach to standardize the decision-making process for patients with complex coronary artery disease (CAD). With percutaneous treatment options for complex CAD increasing, we hypothesized that practice had changed over the past decade-and that more individuals, previously deemed too high risk for intervention, would now be referred for either surgical or percutaneous revascularization.

METHODS

This observational study was conducted at St Thomas' Hospital (London, United Kingdom). All patients discussed at HT meetings were recorded and treatment recommendations audited. A subset of historic cases was selected for blinded, repeat discussion.

RESULTS

From April 2018 to 2019, a total of 52 HT meetings discussing 375 cases were held. Patients tended to be male, with a majority demonstrating multivessel CAD in the context of preserved left ventricular function. SYNTAX scores were balanced across the tertiles. Thirty-five percent of patients had at least 1 chronic total occlusion (mean J-CTO, 3 [interquartile range, 2-3]), affecting the right coronary artery in 60%. Fifteen historic patients with isolated CTOs were re-presented an average of 8 years later; only 3 patients received the same outcome, with 80% now receiving a recommendation for revascularization over medical therapy.

CONCLUSIONS

A dedicated program supporting complex coronary intervention is associated with a change in treatment recommendations issued by the local HT. In line with international guidelines, this might indicate that any complex or multivessel CAD should be discussed at HT meetings with, ideally, the presence of CTO operators.

Comparison of Outcomes of Patients With Acute Myocardial Infarction Between Chronic Total Occlusion Versus 90-99% Stenosis in Non-Culprit Arteries

Patients with acute myocardial infarction (AMI) with chronic total occlusion (CTO) in nonculprit arteries had worse prognosis than patients with AMI without CTO in nonculprit arteries. However, the reason was not clearly explained. This retrospective study aimed to compare the clinical outcomes between patients with AMI with CTO versus those with severe stenosis (90% to 99% stenosis) in nonculprit arteries, which would help to elucidate the role of CTO in nonculprit arteries. We included 643 patients with AMI and divided those into the CTO group (n = 188) and 90% to 99% stenosis group (n = 455). The primary end point was the major adverse cardiovascular events (MACE) defined as the composite of all-cause death, nonfatal myocardial infarction, and readmission for heart failure. During the median follow-up duration of 431 days (Q1:178 days to Q3:950 days), a total of 189 MACE was observed. The Kaplan-Meier curves showed that MACE was more frequently observed in the CTO group than in the 90% to 99% stenosis group (p <0.001). The multivariate Cox hazard analysis revealed that CTO in nonculprit arteries (vs 90% to 99% stenosis) was significantly associated with MACE (hazard ratio 1.410, 95% confidence interval 1.042 to 1.907; p = 0.026) after controlling known confounding factors. In conclusion, patients with AMI with CTO in nonculprit arteries had worse clinical outcomes than those with 90% to 99% stenosis in nonculprit arteries. Patients with AMI with CTO could be recognized as a high-risk group rather than those with 90% to 99% stenosis and should be carefully managed to prevent cardiovascular events.

Angiographic Predictors of Septal Collateral Tracking During Retrograde Percutaneous Coronary Intervention for Chronic Total Occlusion: Anatomical Analysis or Rolling the Dice?

OBJECTIVES

The aim of this study was to identify independent angiographic predictors of collateral channel (CC) tracking success, microcatheter tracking failure, and complications in chronic total occlusion (CTO) retrograde approach. We also developed a "crossability score," comparing its predictive performance with pre-existing scores.

BACKGROUND

The retrograde approach was introduced for recanalization of challenging CTOs. The passage of guidewires through CCs is a key step of the procedure. Two scoring systems have been recently developed to predict CC tracking success.

METHODS

A total of 180 patients and 297 CCs were retrospectively analyzed in an unselected retrograde CTO population.

RESULTS

Guidewire crossing was successful in 203 collaterals (68.3%). The only independent predictor of successful CC tracking was Werner score 2. Conversely, Werner score 0, severe tortuosity (>180°), acute exit angle (<90°), and length of collateral were independently associated with tracking failure. We assigned a score to each "significant" variable to create a model that showed a greater accuracy than pre-existing scores (area under the receiver-operator characteristics curve, 0.72 vs 0.65 and 0.69). Moreover, CC length was also associated with microcatheter tracking failure and complications.

CONCLUSIONS

Werner score 0, tortuosity, acute exit angle, and CC length were independently associated with CC tracking failure, whereas Werner score 2 was a predictor of crossing success. Length of CC is associated with a higher rate of microcatheter crossing failure and complications. We combined these findings into the R-ICPS score, which showed an adequate accuracy for collateral crossing prediction.

Temporal Trends in Retrograde Crossing of Epicardial Collaterals in Chronic Total Occlusion Percutaneous Coronary Intervention

BACKGROUND

The use of retrograde crossings in chronic total occlusion (CTO) percutaneous coronary intervention (PCI) provides higher technical success rates in CTO-PCI. However, the use of epicardial collaterals carries a higher complication risk.

METHODS AND RESULTS

In this study, we aimed to investigate the temporal trends in retrograde crossing of epicardial collaterals, introduction of new guidewires, in-hospital major adverse cardiovascular events (MACE), and technical success rates in a large, multinational registry. We demonstrate that technical success rates increased substantially from about 5%-10% to 76% in the past decade without a concomitant increase in MACE rate (~3% to 4%), likely associated with increased operator experience and introduction of new guidewires. In addition, we show that while high-volume centers have higher technical success, they also have higher perforation rates.

Comparison of successful versus failed percutaneous coronary intervention in patients with chronic total occlusion: A systematic review and meta-analysis

BACKGROUND

The optimal treatment strategy of chronic total occlusion (CTO) is currently debated. This meta-analysis aimed to evaluate the long-term clinical outcomes of successful percutaneous coronary intervention (PCI) of CTO.

METHODS

Electronic databases were searched for studies comparing long-term outcomes between successful PCI in patients with CTO using drug-eluting stents and failed procedures. Meta-analysis was conducted with major adverse cardiac events (MACE) and all-cause mortality during the longest follow-up as endpoints. The combined hazard ratios (HRs) were applied to assess the correlation between successful CTO PCI and MACE/all-cause mortality.

RESULTS

Eight studies consisting of 6,211 patients published between 2012 and 2020 met our inclusion criteria, and the CTO PCI success rate was 81.2%. Patients in the failed group were much older, and more likely to have morbidities (hypertension and prior myocardial infarction), reduced left ventricular ejection fraction, and severe lesion characteristics (multivessel disease and moderate/severe calcification). Pooled results indicated that successful CTO PCI was significantly associated with prognosis. Compared to failed recanalization, patients receiving successful procedures had an improved MACE (HR: 0.50, 95% CI: 0.40-0.61, p < 0.001). Subgroup analyses further revealed the prognostic value of successful CTO PCI. However, no difference was observed regarding all-cause mortality (HR: 0.79, 95% CI: 0.61-1.02, p = 0.074).

CONCLUSIONS

The present study showed that CTO recanalization was associated with improved long-term outcomes. However, randomized trials are needed to confirm the results due to the mismatch of baseline characteristics.