PET evaluation of myocardial perfusion function after percutaneous coronary intervention in patients with chronic total occlusion: a systematic review and meta-analysis

Objective. The benefit of percutaneous coronary intervention (PCI) in chronic complete coronary artery occlusion (CTO) remains controversial. PCI is currently indicated only for symptom and myocardial ischemia abolition, but large chronically occluded vessels with extensive afferent myocardial territories may benefit most from this procedure. The noninvasive evaluation of myocardial perfusion is critical before and after revascularization, and positron emission tomography (PET) can determine absolute myocardial perfusion. Here, we aimed to explore and compare myocardial perfusion in CTO territories and their remote associated areas before and after PCI. Design. We searched for relevant articles published before November 28, 2022, in the Cochrane Library and PubMed. We calculated 95% confidence intervals (CIs) and standardized mean differences (SMDs) for parameters related to myocardial perfusion in CTO territories and remote areas in CTO patients before and after PCI. Results. We included five studies published between 2017 and 2022, with a total of 592 patients. Stress myocardial blood flow (MBF) was increased in CTO territories after PCI when compared to pre-PCI (mean difference [MD]: 1.70, 95% confidence interval [CI] 1.33-2.08, p < 0.001). Coronary flow reserve (CFR) in CTO regions was also higher after PCI (MD 1.37,95% [CI]1.13-1.61, p < 0.001). Stress MBF in remote regions was also increased after PCI (MD 0.27,95% [CI]0.99 ∼ 0.45, p = 0.004), as was CFR in remote regions (MD 0.32,95% [CI] 0.14-0.5, p = 0.001). Conclusions. According to our pooled analysis of current literature, there was an increase in stress MBF and CFR in both CTOs and remote regions after PCI, suggesting that patients with CTO have widespread recovery of blood perfusion after the procedure. These results provide evidence that patients with CTO arteries and high ischemic burdens would indeed benefit from CTO-PCI. Future research on the correlation of ischemia burden reduction with hard clinical endpoints would contribute to a clearer demarcation of the role of CTO PCI with prognostic potential.

Left atrial compression syndrome secondary to coronary artery perforation: Pathophysiology, diagnosis, and management strategies

Coronary perforation (CP) poses a significant risk of morbidity and mortality, particularly, in patients with a history of cardiac surgery. The occurrence of loculated pericardial effusion presents distinctive challenges in these postcardiac surgical patients. This study delves into the complexities arising from the formation of loculated pericardial effusions subsequent to CP, with a specific focus on the loculated effusion in the posterior wall leading to left atrial compression syndrome. This analysis is dedicated to elucidating pathophysiology diagnostic and treatment strategies tailored for addressing left atrium compression syndrome, providing invaluable insights into the intricacies of diagnosing, treating, and managing this entity in the postcardiac surgical patient.

Annual operator volume and procedural outcomes of chronic total occlusions treated with percutaneous coronary interventions: analysis based on 14,899 patients

BACKGROUND

Low operator and institutional volume is associated with poorer procedural and long-term clinical outcomes in patients treated with percutaneous coronary interventions (PCI). This study was aimed at evaluating the relationship between operator volume and procedural outcomes of patients treated with PCI for chronic total occlusion (CTO).

METHODS

Data were obtained from the national registry of percutaneous coronary interventions (ORPKI) collected from January 2014 to December 2020. The primary endpoint was a procedural success, defined as restoration of thrombolysis in myocardial infarction (TIMI) II/III flow without in-hospital cardiac death and myocardial infarction, whereas secondary endpoints included periprocedural complications.

RESULTS

Data of 14,899 CTO-PCIs were analyzed. The global procedural success was 66.1%. There was a direct relationship between the annual volume of CTO-PCIs per operator and the procedural success (OR: 1.006 [95% CI: 1.003-1.009]; P<0.001). The nonlinear relationships of annualized CTO-PCI volume per operator and adjusted outcome rates revealed that operators performing 40 CTO cases per year had the best procedural outcomes in terms of technical success (TIMI flow II/III after PCI), coronary artery perforation rate and any periprocedural complications rate (P<0.0001). Among the other factors associated with procedural success, the following can be noted: multi-vessel, left main coronary artery disease (as compared to single-vessel disease), the usage of rotablation as well as PCI within bifurcation.

CONCLUSIONS

High-volume CTO operators achieve greater procedural success with a lower frequency of periprocedural complications. Higher annual caseload might increase the overall quality of CTO-PCI.

Chronic Total Occlusion Percutaneous Coronary Intervention: Mindset, Culture, and Continuous Improvement

The development of complex and higher-risk indicated procedures (CHIP) and chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has brought new challenges in terms of operator training. Although the technical aspects of learning CHIP/CTO PCI have been described in detail, very little has been discussed concerning the mental skills that the operator must possess or develop to be successful. Moreover, an at least equally important aspect of CHIP/CTO PCI program development is the professional culture of the institution where these complex procedures are performed, because this can mark the difference between a thriving and long-lasting program and one that is quickly bound to fail. This article analyzes the mental attributes of the CHIP/CTO PCI operator and outlines several leadership principles that can be applied to foster a growth culture and develop a thriving program.

Global Consensus Recommendations on Improving the Safety of Chronic Total Occlusion Interventions

Safety is of critical importance to chronic total occlusion (CTO) percutaneous coronary intervention (PCI). This global consensus statement provides guidance on how to optimise the safety of CTO) PCI, addressing the following 12 areas: 1. Set-up for safe CTO PCI; 2. Guide catheter--associated vessel injuries; 3. Hydraulic dissection, extraplaque haematoma expansion, and aortic dissections; 4. Haemodynamic collapse during CTO PCI; 5. Side branch occlusion; 6. Perforations; 7. Equipment entrapment; 8. Vascular access considerations; 9. Contrast-induced acute kidney injury; 10. Radiation injury; 11 When to stop; and, 12. Proctorship. This statement complements the global CTO crossing algorithm; by advising how to prevent and deal with complications, this statement aims to facilitate clinical practice, research, and education relating to CTO PCI.

Retrograde chronic total occlusion percutaneous coronary intervention via ipsilateral collaterals

BACKGROUND

There is limited data on retrograde chronic total occlusion (CTO) percutaneous coronary intervention (PCI) via ipsilateral epicardial collaterals (IEC).

AIMS

To compare the clinical and angiographic characteristics, and outcomes of retrograde CTO PCI via IEC versus other collaterals in a large multicenter registry.

METHODS

Observational cohort study from the Prospective Global registry for the study of Chronic Total Occlusion Intervention (PROGRESS-CTO).

RESULTS

Of 4466 retrograde cases performed between 2012 and 2023, crossing through IEC was attempted in 191 (4.3%) cases with 50% wiring success. The most common target vessel in the IEC group was the left circumflex (50%), in comparison to other retrograde cases, where the right coronary artery was most common (70%). The Japanese CTO score was similar between the two groups (3.13 ± 1.23 vs. 3.06 ± 1.06, p = 0.456); however, the IEC group had a higher Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS-CTO) score (1.95 ± 1.02 vs. 1.27 ± 0.92, p < 0.0001). The most used IEC guidewire was the SUOH 03 (39%), and the most frequently used microcatheter was the Caravel (43%). Dual injection was less common in IEC cases (66% vs. 89%, p < 0.0001). Technical (76% vs. 79%, p = 0.317) and procedural success rates (74% vs. 79%, p = 0.281) were not different between the two groups. However, IEC cases had a higher procedural complications rate (25.8% vs. 16.4%, p = 0.0008), including perforations (17.3% vs. 9.0%, p = 0.0001), pericardiocentesis (3.1% vs. 1.2%, p = 0.018), and dissection/thrombus of the donor vessel (3.7% vs. 1.2%, p = 0.002).

CONCLUSION

The use of IEC for retrograde CTO PCI was associated with similar technical and procedural success rates when compared with other retrograde cases, but higher incidence of periprocedural complications.

Comparative Analysis of Polymer Versus Non-Polymer Jacketed Wires in Chronic Total Occlusion Percutaneous Coronary Intervention

There is significant variation in wire utilization patterns for chronic total occlusion (CTO) percutaneous coronary intervention. This study aimed to compare the outcomes of polymer-jacketed wires (PJWs) versus non-PJWs in anterograde procedures. We analyzed clinical and angiographic characteristics, and procedural outcomes of 7,575 anterograde CTO percutaneous coronary interventions that were performed at 47 centers between 2012 and 2023. Cases in which PJWs were exclusively used were classified in the PJW group, whereas cases where at least one non-PJW was employed were classified in the non-PJW group. Study end points were as follows: technical success, coronary perforation, major adverse cardiac event. PJWs were exclusively used in 3,481 cases (46.0%). These cases had lower prevalence of proximal cap ambiguity, blunt stump, and moderate/severe calcification. They also had lower Japanese CTO (J-CTO), Prospective Global Registry for the Study of Chronic Total Occlusion (PROGRESS-CTO), and PROGRESS-CTO complications scores, higher technical success (94.3% vs 85.7%, p <0.001), and lower perforation rates (2.2% vs 3.2%, p = 0.013). Major adverse cardiac event rates did not differ between groups (1.3% vs 1.5%, p = 0.53). Exclusive use of PJWs was independently associated with higher technical success in both the multivariable (odds ratio [OR] 2.66, 95% confidence interval [CI] 2.13 to 3.36, p <0.001) and inverse probability of treatment weight analysis (OR 2.43, 95% CI 2.04 to 2.89, p <0.001). Exclusive use of PJWs was associated with lower risk of perforation in the multivariable analysis (OR 0.69, 95% CI 0.49 to 0.95, p = 0.02), and showed a similar trend in the inverse probability of treatment weight analysis (OR 0.77, 95% CI 0.57 to 1.04, p = 0.09). Exclusive use of PJWs is associated with higher technical success and lower perforation risk in this non-randomized series of patients.

Intentional creation of dissection flaps to treat perforations during chronic total occlusion percutaneous coronary intervention

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) carries a non-negligible risk of coronary perforation. Definitive treatment of a proximal large vessel perforation often requires the use of covered stents; however, the latter carry significant risk of restenosis and thrombosis, and is not feasible if wire control of the distal vessel has not been achieved. We describe two cases of target vessel perforations during CTO PCI which were treated by the intentional creation of dissection flaps using the subintimal tracking and re-entry technique to seal the perforation.

Ellis type 4 coronary artery perforation during percutaneous coronary intervention: Case series and review

Ellis type 4 coronary artery perforation (CAP4), also referred to as Ellis type 3 cavity-spilling perforation, is a rare but life-threatening complication of percutaneous coronary intervention characterized by extravasation of blood into a cardiac chamber, anatomic cavity, or coronary sinus or vessel. CAP4 is uncommon, accounting for 1.9% to 3.0% of all CAP. Only 11 cases of CAP4 have been reported in detail; we report an additional two cases and review prior reports of this rare complication. Our first case highlights a patient with chronic anginal symptoms due to a 75% concentric stenotic lesion in the mid-LAD. Revascularization was complicated by perforation during pre-dilation with robust contrast extravasation into the left ventricle. Successful postperforation hemostasis was achieved with heparin reversal and covered stent placement. The second case demonstrates another major mechanism of CAP4: wire perforation. During intervention, the absence of blood flow distal to the lesion in the setting of an ST segment elevation myocardial infarction obscured the course of the nonhydrophilic floppy wire leading to perforation that was managed conservatively. In our scoping review, we found that the majority of CAP4 occurred in the LAD. The most frequently involved cavity was the left ventricle-other cavities involved were the right ventricle and coronary veins. Common etiologies of CAP4 included guidewire perforation (62%) and balloon dilation (31%). Perforation was managed with reversal of anticoagulation in 46% of cases, prolonged balloon inflation in 54% of cases, and covered stent deployment in 15% of cases. No patients required surgical repair or pericardiocentesis and perforations were successfully sealed in all cases. In-hospital mortality was 0%.

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.

CTO and Bifurcation Lesions: An Expert Consensus From the European Bifurcation Club and EuroCTO Club

Knowledge in the field of bifurcation lesions and chronic total occlusions (CTOs) has progressively improved over the past 20 years. Therefore, the European Bifurcation Club and the EuroCTO Club have decided to write a joint consensus statement to share general knowledge and practical approaches in this complex field. When percutaneously treating CTOs, bifurcation lesions with relevant side branches (SBs) are found in approximately one-third of cases (35% at the proximal cap, 38% at the distal cap, and 27% within the CTO body). Occlusion of a relevant SB is not rare and has been shown to be associated with procedural complications and adverse outcomes. Simple bifurcation rules are very useful to prevent SB occlusion, and provisional SB stenting is the recommended approach in the majority of cases: protect the SB as soon as possible by wiring it, respect the fractal anatomy of the bifurcation by using the 3-diameter rule, and avoid using dissection and re-entry techniques. A systematic 2-stent approach can be used if needed or sometimes to connect both branches of the bifurcation. The retrograde approach can be very useful to save a relevant SB, especially in the case of a bifurcation at the distal cap or within the CTO body. Intravascular ultrasound is also a very important tool to address the difficulties with bifurcations at the proximal or distal cap and sometimes also within the CTO segment. Double-lumen microcatheters and angulated microcatheters are crucial tools to resolve access difficulties to the SB or the main branch.

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

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

Acute coronary complications in chronic total occlusion interventions

Chronic total occlusion (CTO) interventions are among the most complex procedures within the panorama of percutaneous coronary intervention (PCI). Awareness of potential complications, adequate procedural planning in order to avoid them, and prompt recognition and management should any occur are at the cornerstone of a successful CTO programme. Complications can be acute or late after the procedure and can be cardiac or non-cardiac. Acute cardiac complications can occur directly at the coronary artery level or can have other strictly non-coronary manifestations, such as hypotension, myocardial infarction, arrhythmias, or tamponade. In this review, we focus on acute coronary complications of CTO PCI, in particular their causes, prevention, and management strategies.

Validation of the new PROGRESS-CTO complication risk scores in the OPEN-CTO registry

BACKGROUND

Risk stratification before chronic total occlusion (CTO) percutaneous coronary intervention (PCI) is important to inform procedural planning as well as patients and their families. We sought to externally validate the PROGRESS-CTO complication risk scores in the OPEN-CTO registry.

METHODS

OPEN-CTO is a prospective registry of 1000 consecutive CTO PCIs performed at 12 experienced US centers using the hybrid algorithm. Endpoints of interest were in-hospital all-cause mortality, need for pericardiocentesis, acute myocardial infarction (MI), and major adverse cardiovascular events (MACE) (a composite of all-cause mortality, stroke, periprocedural MI, urgent repeat revascularization, and tamponade requiring pericardiocentesis). Model discrimination was assessed with the area under the curve (AUC) method, and calibration with the observed-versus-predicted probability method.

RESULTS

Mean age was 65.4 ± 10.3 year, and 36.5% of patients had prior coronary artery bypass graft. Overall, 41 patients (4.1%) suffered MACE, 9 (0.9%) mortality, 26 (2.6%) acute MI, and 11 (1.1%) required pericardiocentesis. Technical success was achieved in 86.3%. Patients who experienced MACE had higher anatomic complexity, and more often required antegrade dissection/reentry and the retrograde approach. Increasing PROGRESS-CTO MACE scores were associated with increasing MACE rates: 0.5% (score 0-1), 2.4% (score 2), 3.7% (score 3), 4.5% (score 4), 7.8% (score 5), 13.0% (score 6-7). The AUC were as follows: MACE 0.72 (95% confidence interval [CI]: 0.66-0.78), mortality 0.79 (95% CI: 0.66-0.95), pericardiocentesis 0.71 (95% CI: 0.60-0.82), and acute MI 0.57 (95% CI: 0.49-0.66). Calibration was adequate for MACE and mortality, while the models underestimated the risk of pericardiocentesis and acute MI.

CONCLUSIONS

In a large external cohort of patients treated with the hybrid algorithm by experienced CTO operators, the PROGRESS-CTO MACE, mortality, and pericardiocentesis risk scores showed good discrimination, while the acute MI score had inferior performance.

Validation of the OPEN-CLEAN Chronic Total Occlusion Percutaneous Coronary Intervention Perforation Score in a Multicenter Registry

Coronary artery perforation is one of the most common and feared complications of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). We evaluated the utility of the recently presented OPEN-CLEAN (Coronary artery bypass graft, Length of occlusion, Ejection fraction, Age, calcificatioN) perforation score in an independent multicenter CTO PCI dataset. Of the 2,270 patients who underwent CTO PCI at 7 centers, 150 (6.6%) suffered coronary artery perforation. Patients with perforations were older (69 ± 10 vs 65 ± 10, p <0.001), more likely to be women (89% vs 82%, p = 0.010), more likely to have history of previous coronary artery bypass graft (38% vs 20%, p <0.001), and unfavorable angiographic characteristics such as blunt stump (64% vs 42%, p <0.001), proximal cap ambiguity (51% vs 33%, p <0.001), and moderate-severe calcification (57% vs 43%, p = 0.001). Technical success was lower in patients with perforations (69% vs 85%, p <0.001). The area under the receiver operating characteristic curve of the OPEN-CLEAN perforation risk model was 0.74 (95% confidence interval 0.68 to 0.79), with good calibration (Hosmer-Lemeshow p = 0.72). We found that the CTO PCI perforation risk increased with higher OPEN-CLEAN scores: 3.5% (score 0 to 1), 3.1% (score 2), 5.3% (score 3), 7.1% (score 4), 11.5% (score 5), 19.8% (score 6 to 7). In conclusion, given its good performance and ease of preprocedural calculation, the OPEN-CLEAN perforation score appears to be useful for quantifying the perforation risk for patients who underwent CTO PCI.

Development and validation of a scoring system for predicting clinical coronary artery perforation during percutaneous coronary intervention of chronic total occlusions: the PROGRESS-CTO perforation score

BACKGROUND

Coronary artery perforation is a feared complication of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) and often leads to serious adverse clinical events.

AIMS

We sought to develop a risk score to predict clinical coronary artery perforation in patients undergoing CTO PCI.

METHODS

We analysed clinical and angiographic parameters from 9,618 CTO PCIs in the Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS-CTO). Logistic regression prediction modelling was used to identify variables independently associated with clinical perforation, and the model was internally validated with bootstrapping. Clinical coronary artery perforation was defined as any perforation requiring treatment.

RESULTS

The incidence of clinical coronary perforation was 3.8% (n=367). Five factors were independently associated with perforation and were included in the score: patient age ≥65 years +1 point (odds ratio [OR] 1.79, 95% confidence interval [CI]: 1.37-2.33), moderate/severe calcification +1 point (OR 1.85, 95% CI: 1.41-2.42), blunt/no stump +1 point (OR 1.45, 95% CI: 1.10-1.92), use of antegrade dissection and re-entry +1 point (OR 2.43, 95% CI: 1.61-3.69), and use of the retrograde approach +2 points (OR 4.02, 95% CI: 2.95-5.46). The resulting score showed acceptable performance on receiver operating characteristic (ROC) curve (area under the curve [AUC]: 0.741, 95% CI: 0.712-0.773). The Hosmer-Lemeshow test indicated a good fit (p=0.991), and internal validation with bootstrapping demonstrated good agreement with the model with observed AUC: 0.736 (95% bias-corrected CI: 0.706-0.767).

CONCLUSIONS

The PROGRESS-CTO perforation score may be a useful tool for predicting clinical coronary perforation during CTO PCI.

Predictive performance of the perivascular fat attenuation index for interventional antegrade percutaneous coronary intervention for chronic total occlusion

OBJECTIVES

This study aimed to investigate the association between the perivascular fat attenuation index (FAI) and the success of the antegrade percutaneous coronary intervention (PCI) for chronic total occlusion (CTO).

METHODS

This study evaluated patients with only one CTO lesion observed on conventional coronary angiography (CAG) who underwent coronary computed tomography angiography (CCTA) < 1 month before CAG, from 2018 to 2019. The clinical data, CCTA-based CTO lesion morphologic characteristics, and perivascular FAI of CTO lesions were recorded and analysed.

RESULTS

In total, 156 patients with CTOs were enrolled in this study. Successful antegrade PCI (A-PCI) was achieved in 105 CTO lesions (67.3%). The perivascular FAI of the failed A-PCI group was significantly lower than the successful A-PCI group (-84.76 ± 10.44 Hounsfield unit (HU) vs. -67.54 ± 9.94 HU; p < 0.001), and the cut-off value determined by the receiver operating characteristic (ROC) curve was -77.50 HU. Multivariable analysis revealed no statistical significance in the clinical data, FAI ≤ -77.50 HU (odds ratio (OR): 33.96), negative remodeling (OR: 4.36), severe calcification degree (OR: 4.43) and occlusion length ≥ 20.25 mm (OR: 3.89) were independent predictors of A-PCI failure. The prediction performance of combining the three morphologic characteristics (severe calcification, occlusion length ≥ 20.25 mm, and negative remodeling) with FAI ≤ -77.50 HU was better than that of the three morphologic characteristics alone (0.93 versus 0.77, p < 0.001).

CONCLUSIONS

As a non-invasive index for detecting coronary inflammation, FAI complements indicators based on coronary CTA well and may be helpful for choosing appropriate interventional strategies.

KEY POINTS

• Perivascular FAI of CTO was significantly higher in the failed A-PCI group. • The combination of FAI with other morphological predictors showed higher predictive performance of failed A-PCI for CTOs. • FAI is a good complement to indicators based on coronary CTA.

Coronary Artery Perforations: Glasgow Natural History Study of Covered Stent Coronary Interventions (GNOCCI) Study

Background The objective of the GNOCCI (Glasgow Natural History Study of Covered Stent Coronary Interventions) Study was to report the incidence and outcomes of coronary artery perforations over an 18-year period at a single, high-volume percutaneous coronary intervention center. We considered both the temporal trends and long-term outcomes of covered stent deployment. Methods and Results We evaluated procedural and long-term clinical outcomes following coronary perforation in a cohort of 43,343 consecutive percutaneous coronary intervention procedures. Procedural major adverse cardiac events were defined as a composite of death, myocardial infarction, stroke, target vessel revascularization, or cardiac surgery within 24 hours. A total of 161 (0.37%) procedures were complicated by coronary perforation of which 57 (35%) were Ellis grade III. Incidence increased with time over the study period (r=0.73; P<0.001). Perforation severity was linearly associated with procedural mortality (median 2.9-year follow-up): Ellis I (0%), Ellis II (1.7%), Ellis III/IIIB (21%), P<0.001. Procedural major adverse cardiac events occurred in 47% of patients with Ellis III/IIIB versus 13.5% of those with Ellis I/II perforations (odds ratio, 5.8; 95% CI, 2.7-12.5; P<0.001). Covered stents were associated with an increased risk of stent thrombosis at 2.9-year follow-up (Academic Research Consortium definite or probable; 9.1% versus 0.9%; risk ratio, 10.5; 95% CI, 1.1-97; P=0.04). Conclusions The incidence of coronary perforation increased between 2001 and 2019. Severe perforation was associated with higher procedural major adverse cardiac events and was an independent predictor of long-term mortality. Although covered stents are a potentially lifesaving treatment, the generation of devices used during the study period was limited by their efficacy and high risk of stent thrombosis. Registration Information Clinicaltrials.gov. Identifier: NCT03862352.

Incidence, Mechanisms, Treatment, and Outcomes of Coronary Artery Perforation During Chronic Total Occlusion Percutaneous Coronary Intervention

Coronary artery perforation is a feared complication of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). Our objective was to describe the incidence, mechanisms, treatment, and outcomes of coronary artery perforation during CTO PCI. We analyzed the baseline clinical and angiographic characteristics and procedural outcomes of 10,454 CTO PCIs performed in 10,219 patients between 2012 and 2022. The incidence of coronary perforation was 4.9% (n = 503). Patients who experienced coronary perforation were older and were more likely to have had previous coronary artery bypass graft surgery. Procedures that resulted in perforation were more complex, with higher Japanese CTO and Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS-CTO) scores. Technical (66% vs 87%, p <0.001) and procedural (55% vs 87%, p <0.001) success rates were lower in perforation cases. The CTO target vessel was the most common perforation site (66%). The retrograde approach was responsible for the perforation in 47% of cases, and guidewire exit was the most common perforation mechanism. The proportion of Ellis class 1, 2, 3, and 3 -"cavity spilling" coronary perforations was 20%, 41%, 28%, and 11%, respectively. In 52% of perforations, 1 or more interventions were required: prolonged balloon inflation (23%), covered stent deployment (21%), coil embolization (6%), and/or autologous fat embolization (4%). Tamponade requiring pericardiocentesis occurred in 69 patients (14%). The incidence of major adverse cardiovascular events was higher in perforation cases (18% vs 1.3%, p <0.001). In conclusion, coronary artery perforation occurred in 4.9% of CTO PCIs performed by experienced operators and was associated with lower technical success and higher in-hospital major adverse cardiovascular events.

Predicting Periprocedural Complications in Chronic Total Occlusion Percutaneous Coronary Intervention: The PROGRESS-CTO Complication Scores

BACKGROUND

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) is associated with increased risk of periprocedural complications. Estimating the risk of complications facilitates risk-benefit assessment and procedural planning.

OBJECTIVES

This study sought to develop risk scores for in-hospital major adverse cardiovascular events (MACE), mortality, pericardiocentesis, and acute myocardial infarction (MI) in patients undergoing CTO PCI.

METHODS

The study analyzed the PROGRESS-CTO (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention; NCT02061436) and created risk scores for MACE, mortality, pericardiocentesis, and acute MI. Logistic regression prediction modeling was used to identify independently associated variables, and models were internally validated with bootstrapping.

RESULTS

The incidence of periprocedural complications among 10,480 CTO PCIs was as follows: MACE 215 (2.05%), mortality 47 (0.45%), pericardiocentesis 83 (1.08%), and acute MI 66 (0.63%). The final model for MACE included ≥65 years of age (1 point), moderate-severe calcification (1 point), blunt stump (1 point), antegrade dissection and re-entry (ADR) (1 point), female (2 points), and retrograde (2 points); the final model for mortality included ≥65 years of age (1 point), left ventricular ejection fraction ≤45% (1 point), moderate-severe calcification (1 point), ADR (1 point), and retrograde (1 point); the final model for pericardiocentesis included ≥65 years of age (1 point), female (1 point), moderate-severe calcification (1 point), ADR (1 point), and retrograde (2 points); the final model for acute MI included prior coronary artery bypass graft surgery (1 point), atrial fibrillation (1 point), and blunt stump (1 point). The C-statistics of the models were 0.74, 0.80, 0.78, 0.72 for MACE, mortality, pericardiocentesis, and acute MI, respectively.

CONCLUSIONS

The PROGRESS-CTO complication risk scores can facilitate estimation of the periprocedural complication risk in patients undergoing CTO PCI.

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

AIM

The impact of Grade III coronary perforations (G3-CP) in the setting of CTO-PCI is not well assessed.

METHODS AND RESULTS

We reviewed 7773 CTO-PCI and 98,819 non CTO-PCI performed in 10 European centers: G3 perforation occurred in 87 patients (1.1%) during CTO PCI and 224 patients (0.22%) during non CTO-PCI (p < 0.001). G3-CP involved the CTO segment in 68% of patients and the retrograde channels in 14% of cases. In the CTO PCI group, wire induced G3-CP (50.5% vs. 32.5%, p = 0.02) occurred predominantly when dedicated CTO tapered and highly penetrative wires were used. Intra-procedural and in-hospital death rates were 4.6% vs. 5.8% and 3.6% vs. 7.5% respectively for CTO PCI and non-CTO PCI groups (p = NS). At a median follow up of 24 months, the overall mortality and MAE were respectively 7.8% and MAE 19% without difference among groups.

CONCLUSIONS

We showed similar in-hospital and long-term outcomes when G3 perforations occurred during CTO PCI and non CTO-PCI.

Risk Burden of Coronary Perforation in Chronic Total Occlusion Recanalization: Latin American CTO Registry Analysis

Background

Coronary perforation is a life‐threatening complication of acute percutaneous coronary intervention (PCI) for chronic total occlusions (CTO), but data on midterm outcomes are limited.

Methods and Results

Data from LATAM (Latin American)‐CTO Registry (57 centers; 9 countries) were analyzed. We assessed the risk of 30‐day, 1‐year major adverse cardiac events of coronary perforation using time‐to‐event and weighted composite end point analysis having CTO PCI without perforation as comparators. Additionally, we studied the independent predictors of perforation in these patients. Of 2054 patients who underwent CTO PCI between 2015 and 2018, the median Multicenter CTO Registry in Japan and Prospective Global Registry for the Study of Chronic Total Occlusion Intervention‐Chronic total occlusions scores were 2.0 (1.0–3.0) and 1.0 (0.0–2.0), respectively. The perforation rate was 3.7%, of which 55% were Ellis class 1. After 1‐year coronary perforation had higher major adverse cardiac events rates (24.9% versus 13.3%; P<0.01). Using weighted composite end point, perforation was associated with increased bleeding and ischemic events at 6 months (P=0.04) and 1 year (P<0.01). We found as independent predictors associated with coronary perforation during CTO PCI: maximum activated clotting time (P<0.01), Multicenter CTO Registry in Japan score ≥2 (P=0.05), antegrade knuckle wire (P=0.04), and right coronary artery CTO PCI (P=0.05).

Conclusions

Coronary perforation was infrequent and associated with anatomical and procedural complexity, resulting in higher risk of hemorrhagic and ischemic events. Landmark and weighted analysis showed a sustained burden of major events between 6 months and 1 year follow‐up.

Impact of Timing and Treatment Strategy on Coronary Perforation During Percutaneous Coronary Intervention for Chronic Total Occlusion

Coronary perforations during chronic total occlusion percutaneous coronary intervention (CTO-PCI) are potential complications and reportedly associated with adverse events. This study aimed to describe the clinical characteristics and timing of perforations during CTO-PCI. Data from the Japanese CTO-PCI expert registry included 8,760 patients who underwent CTO-PCI between January 2014 and January 2019. The major adverse cardiac and cerebrovascular events were defined as death, tamponade, myocardial infarction, stent thrombosis, stroke, and revascularization. The guidewire manipulation time was defined as the time required to cross the CTO without perforation. Among these patients, 333 (3.8%) developed perforation during the CTO crossing attempt. Of the 333 patients, 29 developed cardiac tamponades (8.7%). Perforations more frequently occurred in a retrograde wiring than in an anterograde wiring (6.6% vs 1.7%, p <0.0001). A longer guidewire manipulation time was associated with the occurrence of perforation (median 101 minutes [interquartile range 59 to 150 minutes] in the perforation group vs 54.9 minutes [interquartile range 21.1 to 112.7 minutes] in the nonperforation group, p <0.0001). Risk factors for perforation were age, history of coronary bypass graft, right coronary artery lesion, de novo lesion, use of a stiff guidewire, and guidewire manipulation time of >60 minutes during anterograde wiring and age, non-left anterior descending artery lesion, use of a polymer-jacketed guidewire, and use of epicardial channel during retrograde wiring. In conclusion, risk factors for perforation were different between anterograde and retrograde wirings. A prolonged guidewire manipulation time was associated with the occurrence of perforation, especially during anterograde wiring.

Chronic Total Occlusion Percutaneous Coronary Intervention in Patients With Prior Coronary Artery Bypass Graft: Current Evidence and Future Perspectives

Coronary chronic total occlusion (CTO), which occurs in 18. 4-52% of all patients referred for coronary angiography, represents one of the last barriers in coronary intervention. Approximately half of all patients with prior coronary artery bypass graft (CABG), who undergo coronary angiography, are diagnosed with coronary CTO. In fact, these patients often develop recurrent symptoms and events, necessitating revascularization. Currently, there is neither a consensus nor developed guidelines for the treatment of CTO patients with prior CABG, and the prognosis of these patients remains unknown. In this review, we discuss current evidence and future perspectives on CTO revascularization in patients with prior CABG, with special emphasis on clinical and lesion characteristics, procedural success rates, periprocedural complications, and long-term outcomes.

Coronary Artery Perforation Resulting in a Loculated Extracardiac Hematoma

We describe the case of an 86-year-old man with an extensive cardiac history, including previous coronary artery bypass grafting, who experienced a delayed extracardiac hematoma, 350 mL in volume, after retrograde chronic total occlusion—percutaneous coronary intervention. The patient was successfully treated with resultant liquefaction of the hematoma. (Level of Difficulty: Advanced.)

Absorbable Suture Embolization in Distal Coronary Perforation

Coronary artery perforation is a rare but serious complication during percutaneous coronary intervention. Distal or small vessel perforation is usually treated by coil, fat, or microsphere embolization. We describe 5 cases of distal coronary perforation that were managed successfully by a novel technique that uses absorbable sutures. (Level of Difficulty: Advanced.)

Use your head: overcoming epicardial complications during a single-catheter chronic total occlusion-a case-based review

The success of attempts at opening chronic total occlusions (CTO) has dramatically increased in recent times due to the development of new techniques such as the use of the retrograde approach through epicardial collaterals. However, this approach admittedly brings with it an increased risk, and this must be balanced against the potential benefits. We present the case of a 61-year-old gentleman with Canadian Cardiovascular Society (CCS) Class III angina with a background history of hypertension and dyslipidaemia, who was an ex-smoker, and whose diagnostic coronary angiogram revealed CTOs of both the right and left circumflex coronary arteries. Following a heart team discussion, a percutaneous approach to treatment by staged approach was favoured, with the first stage being opening of the CTO of the right coronary artery. A retrograde approach with the use of a Corsair microcatheter facilitated reverse CART (controlled antegrade and retrograde tracking). Unfortunately, upon removal of the Corsair, a rupture of the epicardial collateral was noted with profuse bleeding into the pericardial space. This was treated successfully with a BeGraft-covered stent to obtain proximal control, and a Cooke Tornado neuro-interventional coil to obtain distal control, delivered antegrade through the now recanalized RCA. This case-based review then highlights several unique learning points, in particular to understand, in general terms, the approach to CTO; to understand the potential complications associated with a retrograde epicardial collateral approach; to understand the stepwise approach to dealing with perforation; and, finally, to understand how an occlusion coil works.

Lesion characteristics and procedural complications of chronic total occlusion percutaneous coronary intervention in patients with prior bypass surgery: A meta-analysis

Coronary artery bypass graft (CABG) accelerates the prevalence of native coronary chronic total occlusion (CTO), and this kind of CTO shows extensive challenging and complex atherosclerotic pathology. As a result, the procedural success rate of percutaneous coronary intervention (PCI) is inferior to another kind of lesions. The present meta-analysis aims to compare the lesion characteristics and procedural complications of CTO-PCI in patients with or without prior CABG. A total of 8 studies, comprising of 13439 patients, published from inception to August 2021 were included in this meta-analysis. Results were pooled using random effects model and are presented as odds ratio (OR) with 95% confidence intervals (95% CIs). From the 13439 patients enrolled, 3349 (24.9%) patients had previous CABG and 10090 (75.1%) formed the control group in our analysis. For the clinical characteristic, compared to the non-CABG patients, prior CABG patients were older (OR, 3.98; 95% CI, 3.19-4.78; p < .001; I2  = 72%), had more male (OR, 1.30; 95% CI, 1.14-1.49; p < .001; I2  = 6%), diabetes mellitus (OR, 1.54; 95% CI, 1.36-1.73; p < .001; I2  = 37%), dyslipidemia (OR, 1.89; 95% CI, 1.33-2.69; p < .001; I2  = 81%), hypertension (OR, 1.88; 95% CI, 1.46-2.41; p < .001; I2  = 71%), previous myocardial infarction (OR, 1.94; 95% CI, 1.48-2.56; p < .001; I2  = 85%), and previous PCI (OR, 1.74; 95% CI, 1.52-1.98; p < .001; I2  = 22%). Non-CABG patents had more current smoker (OR, .45; 95% CI, 0.27-0.74; p < .001; I2  = 91%). BMI (OR, -0.01; 95% CI, -0.07-0.06; p = .85; I2  = 36%) were similar in both groups. For lesions location, the right coronary artery (RCA) was predominant target vessel in both groups (50.5% vs 48.7%; p＝.49), although, the left circumflex (LCX) was more frequently CTO in the prior CABG group (27.3% vs 18.9%; p＜.01), while left anterior descending artery (LAD) in non-CABG ones (16.0% vs 29.1%; p＜0.01). For lesions characteristics, prior CABG patients had more blunt stump (OR, 1.71; 95% CI, 1.46-2.00; p < .001; I2  = 40%), proximal cap ambiguity (OR, 1.45; 95% CI, 1.28-1.64; p < .001; I2  = 0.0%), severe calcifications (OR, 2.91; 95% CI, 2.19-3.86; p < .001; I2  = 83%), more bending (OR, 3.07; 95% CI, 2.61-3.62; p < .001; I2  = 0%), lesion length > 20 mm (OR, 1.59; 95% CI, 1.10-2.29; p = .01; I2  = 83%), inadequate distal landing zone (OR, 1.95; 95% CI, 1.75-2.18; p＜.001; I2  = 0.0%), distal cap at bifurcation (OR, 1.65; 95% CI, 1.46-1.88; p < .001; I2  = 0.0%), and higher J-CTO score (SMD, 0.52; 95% CI, 0.42-0.63; p < .001; I2  = 65%). But side branch at proximal entry (OR, 0.88; 95% CI, 0.72-1.07; p = .21; I2  = 45%), in-stent CTO (OR, 0.99; 95% CI, 0.86-1.14; p = .88; I2  = 0.0%), lack of interventional collaterals (OR, 0.80; 95% CI, 0.55-1.15; p = .23; I2  = 78%), and previously failed attempt (OR, 0.73; 95% CI, 0.48-1.11; p = .14; I2  = 89%) were similar in both groups. For complication, prior CABG patients had more perforation with need for intervention (OR, 1.91; 95% CI, 1.36-2.69; p < 0.001; I2  = 34%), contrast-induced nephropathy (OR, 3.40; 95% CI, 1.31-8.78; p = .01; I2  = 0.0%). Non-CABG patents had more tamponade (OR, 0.25; 95% CI, 0.09-0.72; p = .01; I2  = 0.0%), and the major bleeding complication (OR, 1.18; 95% CI, 0.57-2.44; p = .65; I2  = 0%) were no significant difference in both groups. In conclusion, Patients with prior CABG undergoing CTO-PCI have more complex lesion characteristics, though procedural complication rates were comparable.

Update on chronic total occlusion percutaneous coronary intervention

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

Multiple coronary artery perforation following global pericardial tamponade in a patient with prior coronary artery bypass graft surgery: a case report

Background

Patients who undergo coronary artery bypass graft (CABG) surgery rarely develop global pericardial tamponade due to pericardial adhesions. There are no reports of multiple coronary artery perforations following global pericardial tamponade during percutaneous coronary intervention (PCI) in these patients.

Case summary

A 52-year-old male who underwent CABG surgery developed effort angina pectoris. Coronary angiography demonstrated chronic total occlusion (CTO) of the first diagonal branch with severe stenosis of the second diagonal branch. Because his chest pain did not improve with medical therapy and ischaemia of the left ventricular anterolateral wall was confirmed by myocardial scintigraphy, PCI was performed. The second diagonal branch stenosis was passed anterogradely by a 0.014-inch coronary angioplasty guidewire, while the first diagonal branch CTO was recanalized by side-branch intravascular ultrasonography-guided parallel wiring. After stent deployment, coronary artery perforation at the distal end of the second diagonal branch was detected via contrast injection. We immediately performed intravascular haemostasis, leading to the disappearance of contrast. However, multiple bleeding sites were visualized by angiography at different sites of coronary arteries, including the circumflex artery. Although intravascular haemostasis is a standard procedure, we could not control rebleeding. Despite intensive care, the patient died.

Discussion

Increased tissue pressure due to bleeding possibly led to global pericardial tamponade with multiple coronary artery perforations. We report a rare case of a patient with multiple coronary artery perforations during coronary intervention.

Procedural characteristics and outcomes following chronic total occlusion coronary intervention: pooled analysis from 5 registries

BACKGROUND

Recent improvements in clinical skills, technology, and hardware have resulted in improved success rates with chronic total occlusion (CTO) percutaneous coronary intervention (PCI). We performed a study level pooled analysis from the five largest registries of percutaneous coronary intervention (PCI) of CTO.

RESEARCH DESIGN AND METHODS

We conducted pooled analysis of 9500 patients in registries and data on procedural characteristics, technical success, and MACCE was collected.

RESULTS

A total of 9500 patients were included in the analysis. Mean age was 65.4 years with previous CABG in 24.8%, reattempt procedure in 24.8% and mean JCTO score was 2.2. Final wiring strategy in hybrid algorithm-based registries was AWE in 40.8-58%, Retrograde in 24-35%, ADR in 16-25% and in Expert JCTO and EURO CTO was AWE in 72-75% and retrograde in 25-28%. Technical success was achieved in 87.8%. In hospital MACCE was 2.5% (95% CI: 1.8- 3.4%), mortality 0.44% (95% CI: 0.23-0.84%), stroke 0.2% (95% CI: 0.1-0.3%); myocardial infraction 1.6% (95% CI: 1.1-2.2%); and cardiac tamponade 0.8% (95% CI: 0.5 to 1.3%).

CONCLUSION

CTO PCI is currently performed with high technical success rates and low complication rates in experienced hands utilizing various techniques.

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

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

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

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

Unrecognized perforation into the anterior interventricular vein complicating PCI for anterior STEMI: An unexpected detour

Large iatrogenic coronary artery perforations require rapid management; however, operators must be able to recognize guidewire perforation into cardiac veins in order to avoid causing further complications with standard salvage strategies.

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

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

Retrograde Access to Seal a Large Coronary Vessel Balloon Perforation Without Covered Stent Implantation

The sealing of a large vessel coronary perforation during percutaneous coronary intervention typically requires the deployment of 1 or more covered stents. A novel approach to seal a life-threatening perforation caused by unnoticed wire-exit and balloon dilation, utilizing retrograde techniques, without a covered-stent is described. (Level of Difficulty: Advanced.)

Advances in the Post-coronary Artery Bypass Graft Management of Occlusive Coronary Artery Disease

Revascularisation of chronic total occlusion (CTO) represents one of the most challenging aspects of percutaneous coronary intervention, but advances in equipment and an understanding of CTO revascularisation techniques have resulted in considerable improvements in success rates. In patients with prior coronary artery bypass grafting (CABG) surgery, additional challenges are encountered. This article specifically explores these challenges, as well as antegrade methods of CTO crossing. Techniques, equipment that can be used and reference texts are highlighted with the aim of providing potential CTO operators adequate information to tackle additional complexities likely to be encountered in this cohort of patients. This review forms part of a wider series where additional aspects of patients with prior CABG should be factored into decisions and methods of revascularisation.

Five-year report from the Polish national registry on percutaneous coronary interventions with a focus on coronary artery perforations within chronic total occlusions

Introduction

Patients treated within chronic total occlusions (CTO) using percutaneous coronary intervention (PCI) are at increased risk of periprocedural complications.

Aim

To assess the frequency of periprocedural complications with particular emphasis on coronary artery perforations (CAPs) among patients treated with PCIs stratified according to CTOs and their predictors.

Material and methods

Based on a nationwide registry (ORPKI), we analysed 535,853 patients treated with PCI between 2014 and 2018. The study included 12,572 (2.34%) patients treated with CTO PCI. We compared CTO PCI to a non-CTO PCI group before and after propensity score matching (PSM). Multifactorial mixed regression models were used to assess predictors of periprocedural complications and CAPs which occurred within the catheterization laboratory.

Results

Frequencies of all periprocedural complications (2.75% vs. 1.93%, p < 0.001) and CAP (0.72% vs. 0.16%, p < 0.001) were significantly higher in the CTO PCI group. Multifactorial regression analysis performed in the all-comers group of patients treated with PCI showed that PCI within CTO was related to a higher CAP rate (odds ratio (OR) = 2.18; 95% confidence interval (CI): 1.68–2.82, p < 0.001). After PSM, we extracted 5,652 patients treated within CTO and 5,652 patients with non-CTO PCI. CTO PCI was also related to a higher frequency of CAPs (OR = 1.89; 95% CI: 1.11–3.31, p = 0.01).

Conclusions

The frequency of periprocedural complications and CAPs remained stable during the assessed period of time. CTO PCI was confirmed to be among the predictors of increased CAP rate in the overall group of patients treated within CTO.

Definitions and Clinical Trial Design Principles for Coronary Artery Chronic Total Occlusion Therapies: CTO-ARC Consensus Recommendations

Over the past 2 decades, chronic total occlusion (CTO) percutaneous coronary intervention has developed into its own subspecialty of interventional cardiology. Dedicated terminology, techniques, devices, courses, and training programs have enabled progressive advancements. However, only a few randomized trials have been performed to evaluate the safety and efficacy of CTO percutaneous coronary intervention. Moreover, several published observational studies have shown conflicting data. Part of the paucity of clinical data stems from the fact that prior studies have been suboptimally designed and performed. The absence of standardized end points and the discrepancy in definitions also prevent consistency and uniform interpretability of reported results in CTO intervention. To standardize the field, we therefore assembled a broad consortium comprising academicians, practicing physicians, researchers, medical society representatives, and regulators (US Food and Drug Administration) to develop methods, end points, biomarkers, parameters, data, materials, processes, procedures, evaluations, tools, and techniques for CTO interventions. This article summarizes the effort and is organized into 3 sections: key elements and procedural definitions, end point definitions, and clinical trial design principles. The Chronic Total Occlusion Academic Research Consortium is a first step toward improved comparability and interpretability of study results, supplying an increasingly growing body of CTO percutaneous coronary intervention evidence.

Development and validation of a prediction model for angiographic perforation during chronic total occlusion percutaneous coronary intervention: OPEN-CLEAN perforation score

BACKGROUND

Perforation is the most frequent complication of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) and is associated with adverse events including mortality.

METHODS

Among 1,000 consecutive patients enrolled in 12 center prospective CTO PCI study (OPEN CTO), all perforations were reviewed by the angiographic core-lab. Eighty-nine patients (8.9%) with angiographic perforation were compared to 911 patients without perforation. We sought to describe the clinical and angiographic predictors of angiographic perforation during CTO PCI and develop a risk prediction model.

RESULTS

Among eight clinically important candidate variables, independent risk factors for perforation included prior CABG (OR 2.0 [95% CI, 1.2-3.3], p < .01), occlusion length (OR 1.2 per 10 mm increase [95% CI, 1.1-1.3], p < .01), ejection fraction (OR 1.2 per 10% decrease [95% CI, 1.1-1.5], p < .01), age (OR 1.3 per 5 year increase [95%CI, 1.1-1.5], p < .01), and heavy calcification (OR 1.7 [95% CI, 1.0-2.7], p = .04). Three other potential candidate variables, glomerular filtration rate, proximal cap ambiguity, and target vessel, were not independently associated with perforation. The model was internally validated using bootstrapping methods. From the full model, a simplified perforation prediction score (OPEN-CLEAN score: CABG, Length [occlusion], EF < 50%, Age, CalcificatioN) was developed, which discriminated the risk of angiographic perforation well (c-statistics = 0.75) and demonstrated good calibration.

CONCLUSION

This simple 5-variable prediction score may help CTO operators to risk-stratify patients for angiographic perforation using variables available prior to CTO PCI procedures.

Chronic total occlusion percutaneous coronary intervention: managing perforation complications

INTRODUCTION

Coronary artery perforation (CAP) is an infrequent (<1%) complication of percutaneous coronary intervention (PCI), that can lead to dramatic consequences, including tamponade and death. The incidence of CAP is higher (4-9%) in chronic total occlusion (CTO) PCI due higher complexity of these lesions and the techniques used to recanalized them.

AREAS COVERED

In this Expert Review, we discuss the specific features of CTO PCI predisposing to CAP. We also describe the typical procedural scenarios in which CAP can occur and provide a universal management algorithm. Currently available devices and techniques for CAP treatment are presented in detail. Finally, we discuss imaging support for diagnosis of pericardial effusion in CAP as well as medical and surgical management.

EXPERT OPINION

With increasing volumes and complexity of CTO PCI, the incidence of CAP is likely to rise. Adherence to good catheterization laboratory practices, availability of dedicated equipment to seal CAP, perform pericardiocentesis, and provide hemodynamic support, as well as adequate training, are pillars for the prevention and optimal management of CAP during CTO PCI.

Complications of chronic total occlusion percutaneous coronary intervention

Chronic total occlusion percutaneous coronary interventions can be highly complex and are associated with an increased risk of complications, such as perforation, acute vessel closure (which can lead to rapid haemodynamic compromise if it involves the donor vessel), and equipment loss or entrapment. Awareness of the potential complications and meticulous attention to equipment position and patient monitoring can help minimise the risk of complications and allow prompt treatment should they occur.

Impact of adherence to the hybrid algorithm for initial crossing strategy selection in chronic total occlusion percutaneous coronary intervention

INTRODUCTION AND OBJECTIVES

The hybrid algorithm was designed to assist with initial and subsequent crossing strategy selection in chronic total occlusion (CTO) percutaneous coronary interventions (PCIs). However, the success of the initially selected strategy has received limited study.

METHODS

We examined the impact of adherence to the hybrid algorithm recommendation for initial CTO crossing technique selection in 4178 CTO PCIs from a large multicenter registry.

RESULTS

The initial crossing strategy was concordant with the hybrid algorithm recommendation in 1833 interventions (44%). Patients in the concordant group had a similar age to those in the discordant group but a lower mean J-CTO score (2.0 ± 1.4 vs 2.8 ± 1.1; P < .01). The concordant group showed higher technical success with the first crossing strategy (68% vs 48%; P < .01) and higher overall technical success (88% vs 83%; P < .01) with no difference in the incidence of in-hospital major adverse events (1.8% vs 2.3%; P = .26). In multivariable analysis, after adjustment for age, prior myocardial infarction, prior PCI, prior coronary artery bypass grafting, J-CTO score, and scheduled CTO PCI, nonadherence to the hybrid algorithm was independently associated with lower technical success of the initial crossing strategy (odds ratio, 0.55; 95% confidence interval, 0.48-0.64; P < .01).

CONCLUSIONS

Adherence to the hybrid algorithm for initial crossing strategy selection is associated with higher CTO PCI success but similar in-hospital major adverse cardiac events.