Coronary Chronic Total Occlusions Percutaneous Coronary Intervention Research Articles

Impact of sex on myocardial perfusion following percutaneous coronary intervention of chronic total coronary occlusions

ObjectivesWe sought to investigate the impact of sex on myocardial perfusion changes following chronic total coronary occlusion (CTO) percutaneous coronary intervention (PCI) as measured by [15O]H2O positron-emission tomography (PET) perfusion imaging. BackgroundCTO PCI has been associated with an increase in myocardial perfusion, yet females are less likely to undergo revascularization. As such, data on the impact of sex on myocardial perfusion following CTO PCI is scarce. MethodsA total of 212 patients were prospectively enrolled and underwent CTO PCI combined with [15O]H2O PET perfusion imaging prior to and 3 months after PCI. Hyperemic myocardial blood flow (hMBF, mL·min−1·g−1) and coronary flow reserve (CFR) allocated to the CTO territory were quantitatively assessed. ResultsThis study comprised 34 (16 %) females and 178 (84 %) males. HMBF at baseline did not differ between sexes. Females showed a higher increase in hMBF than males (Δ1.34 ± 0.67 vs. Δ1.06 ± 0.74, p = 0.044), whereas post-PCI hMBF was comparable (2.59 ± 0.85 in females vs. 2.28 ± 0.84 in males, p = 0.052). Female sex was independently associated with a higher increase in hMBF after correction for clinical covariates. CFR increase after revascularization was similar in females and males (Δ1.47 ± 0.99 vs. Δ1.30 ± 1.14, p = 0.711). ConclusionsThe present study demonstrates a greater recovery of stress perfusion in females compared to males as measured by serial [15O]H2O PET imaging. In addition, a comparable increase in CFR was found in females and males. These results emphasize the benefit of performing CTO PCI in both sexes. Clinical perspectiveWhat is new?•CTO PCI has been associated with an increase in myocardial perfusion, yet females are less likely to undergo revascularization.•We found a greater recovery of stress perfusion in females compared to males after CTO PCI as measured by serial [15O]H2O PET imaging, whereas coronary flow reserve was comparable between sexes.•The present study adds to the limited body of evidence on the impact of sex on myocardial perfusion following CTO PCI.What are the clinical implications?•Our findings suggest that recovery of myocardial perfusion following CTO PCI is achievable in both female and male patients.•These results underscore the need to adhere to current guidelines for optimal CTO management in both sexes.•Future studies with standardized preprocedural imaging are warranted to increase our understanding of the impact of sex on changes in myocardial perfusion following CTO PCI.

Coronary chronic total occlusion on coronary CT angiography: what radiologists should know?

Coronary chronic total occlusion (CTO) often occurs in patients with obstructive coronary artery disease, which remains one of the greatest challenges for interventional cardiologists. Coronary computed tomography angiography (CCTA) with its emerging post-processing techniques can provide a detailed assessment of CTO lesions before percutaneous coronary intervention (PCI), playing an important role in the clinical management of CTO PCI, from early diagnosis, pre-procedural outcome prediction, the crossing algorithm planning, intraprocedural guidance, and finally post-procedural assessment and follow-up. In addition, the feasibility of CT perfusion (CTP) in patients with CTO has been validated. Combined CCTA and CTP have the great potential to be the one-stop-shop imaging modality for assessing both anatomy and function of CTO lesions. This review aims to make radiologists understand the role of CCTA in the diagnosis and assessment of CTO lesions, thus assisting interventionalists in optimizing CTO PCI crossing strategies with the expertise of radiologists.Critical relevance statement The anatomical features of CTO on CCTA can reveal the complexity of CTO lesions and are associated with CTO PCI outcome, thus helping interventionalists optimize CTO PCI crossing strategies.Key points • CTO is the common lesion in invasive coronary angiography, and CTO PCI is technically difficult and its success rate is relatively low.• Length, collaterals, and attenuation-related signs can help distinguish CTO from subtotal occlusion.• The anatomical features of CTO lesions can help grade the difficulty of CTO PCI and predict procedural outcomes and long-term outcomes of CTO PCI.• The real-time fusion of CCTA with fluoroscopic angiography can be applied in highly complicated CTO lesions.• After CTO PCI, CCTA can help guide a second CTO PCI re-entry or followup stent patency.

Same day discharge after large bore vascular access in percutaneous coronary intervention of chronic total coronary occlusions

Abstract Background Same day discharge (SDD) in patients undergoing percutaneous coronary intervention (PCI) of a chronic total coronary occlusion (CTO) appears feasible, safe, and carries economic advantage. However, SDD may be hampered by the application of large bore dual arterial access, due to its association with vascular complications. Nevertheless, increasing French size augments therapeutic options and is therefore considered fundamental in complex CTO PCI. Purpose The present study investigated the feasibility of SDD in patients undergoing CTO PCI with large bore dual arterial access. Methods Between 2013 and 2018, a total of 683 patients were prospectively enrolled in a single-center CTO registry and underwent single-vessel CTO PCI. Large bore arterial access was defined as the application of 7 and/or 8 French sheaths in at least one access site. Technical success was defined as Thrombolysis in Myocardial Infarction flow grade 3 and residual stenosis <30%. Vascular access complications were defined as a composite of clinically significant bleeding and/or hematoma, urgent transfusion, dissection, pseudoaneurysm, arteriovenous fistula formation, and thrombosis. Results Mean age was 66 ± 11 years; 83% were male. Large bore arterial access was applied in 87%; the most common set-up was radial-femoral (68%) and bifemoral (23%) access. In 432 (62%) patients, SDD was achieved. Patients within the SDD group were younger and had lower rates of prior MI, prior CABG, renal insufficiency, and peripheral artery disease. A high Japanese CTO score (≥2) was less common in patients with versus without SDD (58% vs. 72%, p<0.001). In addition, technical success rate was higher in the SDD group (96% vs. 89%, p<0.001). Vascular access complications were found in 22 (3,2%) cases, with 17 (77,2%) occurring in the non-SDD group. Local access site bleeding was found to be the most common complication (82,4% of total vascular access complications). Finally, multivariable analysis showed that female gender (OR 2.22, 95% CI: 1.30 – 3.78) and local access site bleeding (OR 12.0, 95% CI: 4.37 – 33.21) were significantly associated with a lower probability of SDD. Conclusions Our study demonstrates the feasibility of SDD in the majority of patients undergoing CTO PCI with large bore dual arterial access, with high rates of technical CTO PCI success and acceptable vascular access complication rates. Care should be taken to avoid local access site bleeding since this hinders SDD.

Trends and outcomes of intravascular imaging in patients undergoing percutaneous coronary intervention for coronary chronic total occlusion: a 5-year retrospective analysis

Abstract Background Elderly patients with coronary chronic total occlusions (CTO) represent a vulnerable population with comorbid conditions and complex coronary anatomy. Intracoronary imaging has become an important tool in the treatment of complex lesions with percutaneous coronary intervention (PCI). There is limited data on its impact in patients undergoing percutaneous coronary intervention (PCI) for coronary CTO. Purpose We aimed to identify the trends in utilization of intravascular ultrasound (IVUS) and optical coherence tomography (OCT) in patients undergoing single vessel (SV) - CTO PCI and its impact on clinical outcomes. Methods We queried the Nationwide Inpatient Sample database to identify hospitalizations for SV PCI between 2016 – 2020. Patients with CTO were identified using the ICD-10 diagnosis code. The use of IVUS and OCT was identified using the ICD-10 codes. We compared utilization of IVUS-OCT for SV-CTO PCI to those without and studied the impact of their utilization on clinical outcomes. The primary outcome was major adverse cardiovascular and cerebrovascular events (MACCE). Secondary outcomes included in-hospital mortality, re-infarction, stroke and post-procedural AKI. Outcomes were compared using univariate and multivariate logistic regression analysis. Results A total of 135,745 weighted hospitalizations for SV CTO-PCI were identified of which 13,610 (10%) utilized IVUS/OCT (mean age 66+/-12, 26.5 % females). Hospitalizations were stratified by patient age into a younger cohort <75 years (mean age 61 ± 9 years) and an older cohort ≥75 years (mean age 81 + 4). Male sex, Caucasians, and admissions to a large urban hospital were associated with higher IVUS/OCT use in both cohorts (p < 0.001). The use of IVUS/OCT was associated with significantly lower MACCE (aOR 0.73, 95% CI 0.6 - 0.8, p < 0.001) and lower incidence of re-infarction in both cohorts (OR 0.6, 95% CI 0.5-0.6, p<0.001 for both cohorts). In-hospital mortality was significantly lower in both cohorts utilizing intravascular imaging (OR 0.8, 95% CI 0.7-1.0, p<0.05 for age ≥75 years and OR 0.6, 95% CI 0.5-0.7, p <0.001) for age < 75). Overall, the rates of stroke and length of stay (4 + 5 days) were comparable but associated with higher hospitalization costs (153k-170k vs 110k-120k, p < 0.001). In patients undergoing CTO-PCI, there was an increasing trend towards the utilization of IVUS and OCT over the study period. Conclusion The use of IVUS/OCT guidance for CTO-PCI was associated with a significant reduction in MACCE, re-infarction and in hospital mortality regardless of age. There was a significant increase in the utilization of IVUS and OCT for the study period in all groups.

Percutaneous coronary intervention versus optimal medical therapy for chronic total occlusion: an updated meta-analysis of randomized controlled trials comparing clinical and health status outcomes

Abstract Background The prevalence of coronary chronic total occlusion (CTO) varies widely from 18-52% in patients with stable ischemic heart disease. Despite recent advances in operator techniques and improving operator experience, percutaneous coronary intervention (PCI) for CTO still poses a major challenge. While several observational studies have demonstrated superior outcomes for CTO-PCI, the overall benefit of CTO intervention remains controversial. Purpose We aimed to compare the clinical endpoints and health status outcomes in all randomized controlled trials (RCT's) to evaluate safety and efficacy of PCI as compared to optimal medical therapy (OMT). Methods We queried PubMed/MEDLINE, Cochrane Library and EMBASE for RCT’s that compared CTO-PCI with OMT. The primary endpoint was all-cause mortality. Secondary outcomes included cardiac mortality, major adverse cardiac and cerebrovascular events (MACCE), myocardial infarction (MI), target vessel revascularization (TLR), stent thrombosis, left ventricle ejection fraction (LVEF) changes and health status outcomes. Risk ratios (RR’s) and their corresponding 95% confidence intervals (CIs) were calculated using the random-effects model. Results We included a total of 6 RCT’s (1890 total patients, mean age 61.8±3.6, and 84.6 % male) Follow-up ranged from 4 to 48 months. All-cause mortality and cardiac mortality were comparable between CTO-PCI and OMT groups (RR 0.83; 95% CI 0.47 – 1.48; p = 0.53 and RR 0.98; 95% CI 0.24 – 4.07; p = 0.98, respectively). There was no significant difference between PCI or medical therapy with regards to MACCE (RR 0.85; 95% CI 0.50 – 1.45; p = 0.55) and TLR at follow-up (RR 0.50, 95% CI 0.24 – 1.06; p = 0.07). Moreover, the risk for MI (RR 1.36; 95% CI 0.91 – 2.-2; p = 0.13), stent thrombosis (RR 1.74; 95% CI 0.36 – 8.40; p = 0.49), and stroke at follow-up (RR 0.57; 95% CI 0.24 – 1.38; p = 0.21) was comparable between the two groups. Health status outcomes such as angina frequency (RR 4.05; 95% CI –1.95 – 10.05; p = 0.19), physical limitations (RR 3.83; 95% CI –0.75 – 8.41; p = 0.10), quality of life (RR 6.25; 95% CI –1.54 – 14.03; p = 0.12), and treatment satisfaction (RR 2.60; 95% CI –1.15 – 6.35; p = 0.17), were comparable between the two groups. Conclusion Pooled data from RCT does not support an advantage to CTO PCI in terms of a reduction in cardiovascular events or improved quality of life. Further adequately powered and long-term trials are required to identify the best management strategy for patients with coronary CTO.Figure 1Figure 2

Collateral grading systems in retrograde percutaneous coronary intervention of chronic total occlusions.

The Japanese Channel (J-Channel) score was introduced to aid in retrograde percutaneous coronary intervention (PCI) of chronic total coronary occlusions (CTOs). The predictive value of the J-Channel score has not been compared with established collateral grading systems such as the Rentrop classification and Werner grade. To investigate the predictive value of the J-Channel score, Rentrop classification and Werner grade for successful collateral channel (CC) guidewire crossing and technical CTO PCI success. A total of 600 prospectively recruited patients underwent CTO PCI. All grading systems were assessed under dual catheter injection. CC guidewire crossing was considered successful if the guidewire reached the distal segment of the CTO vessel through a retrograde approach. Technical CTO PCI success was defined as thrombolysis in myocardial infarction flow grade 3 and residual stenosis <30%. Of 600 patients, 257 (43%) underwent CTO PCI through a retrograde approach. Successful CC guidewire crossing was achieved in 208 (81%) patients. The predictive value of the J-Channel score for CC guidewire crossing (area under curve 0.743) was comparable with the Rentrop classification (0.699, p = 0.094) and superior to the Werner grade (0.663, p = 0.002). Technical CTO PCI success was reported in 232 (90%) patients. The Rentrop classification exhibited a numerically higher discriminatory ability (0.676) compared to the J-Channel score (0.664) and Werner grade (0.589). The J-channel score might aid in strategic collateral channel selection during retrograde CTO PCI. However, the J-Channel score, Rentrop classification, and Werner grade have limited value in predicting technical CTO PCI success.

Three-year outcomes of A Randomized Multicentre Trial Comparing Revascularization and Optimal Medical Therapy for Chronic Total Coronary Occlusions (EuroCTO)

Percutaneous coronary intervention (PCI) for chronic total coronary occlusions (CTO) improves clinical symptoms and quality of life. The longer-term safety of PCI compared to optimal medical therapy (OMT) remains uncertain. We sought to evaluate the long-term safety of PCI for CTO in a randomised trial as compared to OMT. A total of 396 patients with a symptomatic CTO were enrolled into a randomised, multicentre clinical trial comparing PCI and OMT. Half of the patients had a single CTO; the others had multivessel disease. Non-CTO lesions were treated prior to randomisation (2:1 ratio). During follow-up, crossover from OMT to PCI occurred in 7.3% (1 year) and 17.5% (3 years) of patients. At 3 years, the incidence of cardiovascular death or nonfatal myocardial infarction was not significantly different between the groups (OMT 3.7% vs PCI 6.2%; p=0.29). By per-protocol analysis, the difference remained non-significant (OMT 5.7% vs PCI 4.7%; p=0.67). Overall, major adverse cardiovascular events (MACE) were more frequent with OMT (OMT 21.2% vs PCI 11.2%), largely because of ischaemia-driven revascularisation. The rates of stroke or hospitalisation for bleeding were not different between the groups. At 3 years there was no difference in the rate of cardiovascular death or myocardial infarction between PCI or OMT among patients with a remaining single coronary CTO. The MACE rate was higher in the OMT group due largely to ischaemia-driven revascularisation. CTO PCI appears to be a safe option for patients with a single remaining significant coronary CTO. CinicalTrials.gov: NCT01760083.

Abstract P103: Higher Preoperative Plasma Aldosterone Concentrations Are Associated With Elevated Risk Of Atrial Fibrillation After Chronic Total Occlusion Percutaneous Coronary Intervention

Background: Postoperative atrial fibrillation (POAF) is associated with poor outcomes in patients with coronary chronic total occlusions (CTO). Aldosterone is a steroid hormone that regulates fluid and electrolyte homeostasis and is known to increase the risk of proarrhythmia. This study aimed to explore the additional value of preoperative plasma aldosterone levels for predicting POAF after CTO percutaneous coronary intervention (PCI). Methods: We conducted a prospective cohort study involving consecutive patients with a left ventricular ejection fraction (LVEF) greater than 50% requiring CTO-PCI in the First Affiliated Hospital of Chengdu Medical College. Patients were excluded if they had a history of AF, preoperative endocarditis and/or a ventricular assist device. Plasma aldosterone levels, echocardiography and transforming growth factor beta1 (TGF-β1) examination were assessed before percutaneous recanalization. The primary endpoint was the occurrence of POAF within 30 days after percutaneous recanalization. New-onset POAF after CTO-PCI was defined as any episode detected via continuous in-hospital electrocardiogram/telemetry monitoring and documented by a physician in the chart, regardless of duration or need for treatment. Results: Thirty-eight of 268 (14.2%) patients had POAF. Compared with controls, patients experiencing POAF were significantly older, had a higher body mass index, had diabetes and hypertension, and had higher preoperative plasma aldosterone levels. In logistic regression analysis, higher plasma aldosterone levels exhibited 1.75-fold higher odds (95% confidence interval [CI], 1.15-2.32, P=0.004) for the presence of POAF, which was significant in the adjusted model (odds ratio [OR], 1.82 [95% CI, 1.21-2.45], P=0.007). Reverse transcriptase PCR analysis performed on the left atrial appendage and plasma examination revealed that TGF-β1 was activated in POAF patients. Conclusion: Higher plasma aldosterone levels are associated with increased odds for POAF in patients with CTO-PCI, even in the absence of primary aldosteronism, implying that plasma aldosterone levels might be a target for POAF risk stratification after CTO-PCI.

Incidence, Predictors, and Strategies for Retrograde Wire Tracking Failure via Poor Septal Collateral Channels in Chronic Total Occlusion.

Retrograde guidewire (GW) tracking success via a poor septal collateral channel (CC) when an antegrade approach fails is crucial for successful revascularization of coronary chronic total occlusion (CTO) with poor septal CC. However, the incidence, predictors, and management strategies for retrograde GW tracking failure via poor septal CC remain unclear. In total, 122 CTO patients who underwent retrograde septal percutaneous coronary intervention (PCI) with poor CC between January 2017 and May 2022 were retrospectively analyzed. Patients were divided into the retrograde GW tracking success group (success group) and the retrograde GW tracking failure group (failure group). Clinical and angiographic data were compared to investigate the predictors of retrograde GW tracking failure. The incidence of GW tracking failure was 22.1% (27/122). Patients in the failure group had a higher prevalence of left anterior descending artery (LAD) CTO (66.7% vs 37.9%; p = 0.009) and a higher incidence of well-developed non-septal collateral (66.7% vs 30.5%; p = 0.001). Patients with a septal CC diameter ≥ 1 mm (48.1% vs 70.5%; p = 0.040), ≥ 3 septal CCs (44.4% vs 66.3%; p = 0.046), and initial retrograde application of Guidezilla (37.0% vs 60.0%; p = 0.048) were significantly lower in the failure group than in the success group. The binary logistics regression model showed that a CC diameter < 1 mm, well-developed non-septal collateral, and LAD CTO were independent predictors for GW tracking failure in patients undergoing retrograde CTO PCI via poor septal CC. The success rate of retrograde GW tracking via poor septal CC was high, with a relatively high procedural success rate. A CC diameter < 1 mm, well-developed non-septal collateral, and LAD CTO were independent predictors of GW tracking failure in patients undergoing retrograde CTO PCI via poor septal CC.

Contemporary issues of percutaneous coronary intervention in heavily calcified chronic total occlusions: an expert review from the European CTO Club.

Severe calcification is frequent in coronary chronic total occlusions (CTO), and its presence has been associated with increased procedural complexity and poor long-term outcomes following percutaneous coronary intervention (PCI) in an already challenging anatomical setting. The diagnostic characterisation of heavily calcified CTOs using non-invasive and invasive imaging tools can lead to the application of different therapeutic options during CTO PCI, in order to achieve adequate lesion preparation and optimal stent implantation. In this expert review, the European Chronic Total Occlusion Club provides acontemporary, methodological approach, specifically addressing heavily calcified CTOs, suggesting an integration of evidence-based diagnostic methods to tailored, up-to-date percutaneous therapeutic options.

The challenges of a randomised placebo-controlled trial of CTO PCI vs. placebo with optimal medical therapy: The ORBITA-CTO pilot study design and protocol.

Percutaneous coronary intervention (PCI) for coronary chronic total occlusion (CTO) has been performed for the improvement of symptoms and quality of life in patients with stable angina. The ORBITA study demonstrated the role of the placebo effect in contemporary PCI in non-CTO chronic coronary syndromes. However, the benefit of CTO PCI beyond that of a placebo has not been demonstrated. The ORBITA-CTO pilot study will be a double-blind, placebo-controlled study of CTO PCI randomising patients who have: (1) been accepted by a CTO operator for PCI; (2) experienced symptoms due to a CTO; (3) evidence of ischaemia; (4) evidence of viability within the CTO territory; and (5) a J-CTO score ≤3. Patients will undergo medication optimisation that will ensure they are on at least a minimum amount of anti-anginals and complete questionnaires. Patients will record their symptoms on an app daily throughout the study. Patients will undergo randomisation procedures, including an overnight stay, and be discharged the following day. All anti-anginals will be stopped after randomisation and re-initiated on a patient-led basis during the 6-month follow-up period. At follow-up, patients will undergo repeat questionnaires and unblinding, with a further 2-week unblinded follow-up. The co-primary outcomes are feasibility (blinding) in this cohort and angina symptom score using an ordinal clinical outcome scale for angina. Secondary outcomes include changes in quality-of-life measures, Seattle Angina Questionnaire (SAQ), peak VO2, and anaerobic threshold on the cardiopulmonary exercise test. The feasibility of a placebo-controlled CTO PCI study will lead to future studies assessing efficacy. The impact of CTO PCI on angina measured using a novel daily symptom app may provide improved fidelity in assessing symptoms in patients with CTO's.

Early and long-term prognosis in patients with remaining chronic total occlusions after revascularization attempt. A cohort study from the SKEJ-CTO registry

Objectives The present study aimed to compare safety and long-term prognosis of patients with chronic total coronary occlusions (CTO) stratified for remaining CTOs after percutaneous coronary intervention (PCI). Design The study cohort consisted of patients with coronary artery disease who underwent CTO PCI in a high volume tertiary center from 2009 to 2019 and were registered in Danish high-quality registers. Patients with successful PCI of all CTOs were compared to patients with ≥1 remaining CTO post-procedural. Primary endpoints were analysed using Cox-regression and Kaplan-Meier estimates, and included all-cause mortality, major adverse cardio- and cerebrovascular events (MACCE) and a 30-day safety endpoint. Results Procedural success rate was 87.7%, and 76.5% of patients had all CTO(s) opened post-PCI. Safety endpoint occurred in 4.6% of patients, and more frequently in patients with remaining CTO(s) (RD 4.9, 95%CI 0.1, 9.8). All-cause mortality was higher in patients with remaining CTO(s) (Unadjusted HR 1.65, 95% CI 1.03, 2.47, p = .015. Adjusted HR 1.32, 95%CI 0.88–1.99, p = .18) after eight years of follow-up. Risk of MACCE was significantly higher in patients with remaining CTO(s) (Unadjusted HR 1.79, 95% CI 1.34–2.41, p < .001. Adjusted HR 1.51, 95% CI 1.11–2.05, p = .009). Conclusions In our centre, CTO PCI was associated with high success rate and low risk of 30-days complications. Presence of remaining CTO(s) after final revascularization attempt was associated with higher but statistically insignificant long-term mortality but was an independent predictor of MACCE.

Abstract 14158: Impact of Gender Differences on Changes in Myocardial Perfusion Following Percutaneous Coronary Intervention of Chronic Total Coronary Occlusions

Introduction. Data on gender differences in chronic total coronary occlusion (CTO) percutaneous coronary intervention (PCI) are scarce. Prior studies have demonstrated CTO PCI to reduce ischemia, however female patients are less likely to undergo revascularization. This study sought to investigate the impact of gender on myocardial perfusion changes following CTO PCI as measured by [ 15 O]H 2 O positon-emission tomography (PET) perfusion imaging. Methods. A total of 212 patients were prospectively enrolled in a single-center CTO registry and underwent single-vessel CTO PCI, combined with [ 15 O]H 2 O PET imaging at baseline and three months follow-up. Baseline and follow-up resting myocardial blood flow (MBF), hyperemic MBF and coronary flow reserve (CFR) allocated to the CTO territory were quantitatively assessed. The presence of residual ischemia was defined as hMBF ≤2.3 mL·min -1 ·g -1 in the CTO area at follow-up. Results. This study comprised 34 (16%) females and (84%) males. Mean age in females was higher compared to males (68 ± 9 vs. 61 ± 10 years, p&lt;0.01). In women, resting MBF at baseline was more elevated than in men (1.02 ± 0.24 vs. 0.84 ± 0.21 mL·min -1 ·g -1 , p&lt;0.01). Similarly, baseline hMBF was found to be higher in females (1.81 ± 0.53 vs. 1.64 ± 0.53 mL·min -1 ·g -1 , p=0.03), and showed a higher increase after CTO PCI (Δ1.06 ± 0.71 vs. Δ0.71 ± 0.66 mL·min -1 ·g -1 , p=0.01). Improvement in CFR after CTO PCI was more evident in female patients (Δ1.17 ± 1.04 vs. Δ0.82 ± 0.89, p=0.04). At three months follow-up, the proportion of patients with residual ischemia was lower in women versus men (9 (27%) vs. 91 (51%), p=0.01). Conclusions. We found a higher increase in hyperemic MBF and CFR following CTO PCI in women compared to men, as measured by serial [ 15 O]H 2 O PET imaging. In addition, lower rates of residual ischemia were observed in women. This study suggests the potential benefit of a lower threshold for CTO PCI in female patients.

Impact of percutaneous coronary intervention of chronic total occlusions on absolute perfusion in remote myocardium.

Revascularisation of a chronic total coronary occlusion (CTO) impacts the coronary physiology of the remote myocardial territory. This study aimed to evaluate the intrinsic effect of CTO percutaneous coronary intervention (PCI) on changes in absolute perfusion in remote myocardium. A total of 164 patients who underwent serial [15O]H2O positron emission tomography (PET) perfusion imaging at baseline and three months after successful single-vessel CTO PCI were included to evaluate changes in hyperaemic myocardial blood flow (hMBF) and coronary flow reserve (CFR) in theremote myocardium supplied by both non-target coronary arteries. Perfusion indices in CTO and remote myocardium showed a positive correlation before (resting MBF: r=0.84, hMBF: r=0.75, and CFR: r=0.77, p<0.01 for all) and after (resting MBF: r=0.87, hMBF: r=0.87, and CFR: r=0.81, p<0.01 for all) CTO PCI. Absolute increases in hMBF and CFR were observed in remote myocardium following CTO revascularisation (from 2.29±0.67 to 2.48±0.75 mL·min-1·g-1 and from 2.48±0.76 to 2.74±0.85, respectively, p<0.01 for both). Improvements in remote myocardial perfusion were largest in patients with a higher increase in hMBF (β 0.58, 95% CI: 0.48-0.67, p<0.01) and CFR (β 0.54, 95% CI: 0.44-0.64, p<0.01) in the CTO territory, independent of clinical, angiographic and procedural characteristics. CTO revascularisation resulted in an increase in remote myocardial perfusion. Furthermore, the quantitative improvement in hMBF and CFR in the CTO territory was independently associated with the absolute perfusion increase in remote myocardial regions. As such, CTO PCI may have a favourable physiologic impact beyond the intended treated myocardium.

Outcomes of chronic total occlusion percutaneous coronary intervention in patients with reduced left ventricular ejection fraction.

The relationship between left ventricular ejection fraction (LVEF) and the success and safety of coronary chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has received limited study. We examined the clinical characteristics and outcomes of CTO PCI in the Prospective Global Registry for the Study of CTO Intervention (PROGRESS-CTO) after stratifying patients by LVEF (≤35%, 36%-49%, and ≥50%). A total of 7827 CTO PCI procedures with LVEF data were included. Mean age was 64 ± 10 years, 81% were men, 43% had diabetes mellitus, 61% had prior PCI, 45% had prior myocardial infarction, and 29% had prior coronary artery bypass graft surgery. Technical success was similar in the three LVEF strata: 85%, 86%, and 87%, p = 0.391 for LVEF ≤35%, 36%-49%, and ≥50%, respectively. In-hospital mortality was higher in lower LVEF patients (1.1%, 0.4%, and 0.3%, respectively, p = 0.001). In-hospital major adverse cardiovascular events (MACE) were numerically higher in lower EF patients (2.7%, 2.1%, and 1.9%, p = 0.271). At a median follow-up of 2 months (interquartile range: 19-350 days), patients with lower LVEF continued to have higher mortality (4.9%, 3.2%, and 1.4%, p < 0.001) while the MACE rates were similar (9.3%, 9.6%, and 7.4%, p = 0.172). CTO PCI can be performed with high technical success in patients with reduced LVEF but is associated with higher in-hospital and post-discharge mortality.

Validation of the newly introduced CASTLE Score for predicting successful CTO recanalization.

BackgroundThe new EuroCTO CASTLE Score was validated against the widely adopted Japanese Multicenter CTO Registry (J-CTO) score in predicting technical success in percutaneous coronary intervention (PCI) for coronary chronic total occlusions (CTO).MethodsA total of 463 patients treated by CTO PCI were included in a retrospective analysis. Result: The mean CASTLE score was 2.23 ± 1.1 and J-CTO score was 2.84 ± 1.0. The overall technical success rate was 83.2%. At 30 days follow up, a primary composite safety endpoint showed a low proportion of stent thrombosis (0.2%) and re-hospitalization (0.4%). Moreover, an improvement of clinical symptoms was found in 83% of patients. Receiver operating characteristic analysis (ROC) demonstrated a comparable overall discriminatory performance in predicting technical outcome: CASTLE score, area under the ROC curve (AUC) 0.668, 95% CI: 0.606–0.730; J-CTO score AUC 0.692, 95% CI: 0.631–0.752; Comparison of AUCs: p = 0.324. Those findings were even consistent in more complex procedures CASTLE Score ≥ 4 and J-CTO score ≥ 3: CASTLE Score AUC 0.514, 95% CI: 0.409–0.619; J-CTO score, AUC 0.617, 95% CI: 0.493–0.741; Comparison of AUCs: p = 0.211. Furthermore, increasing score values are accompanied by a longer examination and fluoroscopy time, more contrast medium and a higher dose area product.ConclusionCompared to the widely accepted J-CTO score, the new introduced EuroCTO CASTLE score demonstrated a comparable overall discriminatory performance in predicting technical outcomes in CTO PCI.

Contemporary Strategies and Outcomes of Dedicated Chronic Total Occlusion Percutaneous Coronary Intervention Programs: A Prospective Multicentre Registry

Background The field of CTO PCI is expanding, but successful and safe percutaneous coronary intervention (PCI) of coronary chronic total occlusions (CTO) requires a substantial resource and experience investment. We aimed to assess temporal trends in strategies and outcomes of 2 dedicated programs for CTO PCI. Methods Between 2011 and 2020, 920 CTO PCI procedures were prospectively included at 2 referral centres in Belgium. Temporal trends were assessed, and logistic regression models were built to identify predictors of outcome. Results Despite an increase in lesion complexity (the J-CTO score increased from 1.3 in year 1 to 1.7–2.0 in years 8-9, p < 0.001), technical success improved from 70.0% to 85.6% in year 9 (p value for trend <0.001). We observed the most significant improvement starting at years 3-4 (OR 2.3 in year 4 versus year 1, p=0.018). Together with an increase in success rates and lesions complexity, there was an increase in the use of dual injections, retrograde approaches, the number of balloons and stents, and the use of microcatheters. Conversely, there was a decrease in large bore access, an increase in radial approach, and a shift towards contemporary dissection/reentry techniques. This strategy resulted in a stable major complication rate of 4.7% (p value for trend 0.33). The rate of coronary procedure-related myocardial injury was high (71.0%) and was associated with the use of more intracoronary devices. Conclusions Three to four years after initiation of a dedicated CTO PCI program with 50 CTO PCIs per year, consistent high technical success and low complication rates are achieved using contemporary strategies.

Abstract 10176: Absolute Perfusion Increase in Remote Myocardium Following Chronic Total Coronary Occlusion Percutaneous Coronary Intervention

Introduction: Successful revascularization of a chronic total coronary occlusion (CTO) impacts coronary physiology of the remote myocardial territory. This study evaluated the impact of CTO percutaneous coronary intervention (PCI) on absolute perfusion in remote myocardium. Methods: A total of 164 patients underwent serial [ 15 O]H 2 O positron emission tomography (PET) perfusion imaging at baseline and 3 months after successful CTO PCI to evaluate changes in hyperemic myocardial blood flow (hMBF) and coronary flow reserve (CFR) in remote myocardium subtended by non-target collateral donor coronary arteries. Results: Absolute perfusion indices in the CTO and remote myocardium showed a positive linear correlation before (hMBF: r=0.75, p&lt;0.01; CFR: r=0.77, p&lt;0.01) and after (hMBF: r=0.87, p&lt;0.01; CFR: r=0.81, p&lt;0.01) CTO PCI. An increase in absolute myocardial perfusion (hMBF: 2.29±0.67 to 2.48±0.75 mL·min -1 ·g -1 , p&lt;0.01; CFR: 2.48±0.76 to 2.74±0.85, p&lt;0.01) was observed in the remote myocardial territory between baseline and follow-up. Improvements in remote myocardial perfusion were largest in patients with higher increases in hMBF (β 0.55, 95% CI: 0.46-0.64, p&lt;0.01) and CFR (β 0.52, 95% CI: 0.43-0.61, p&lt;0.01) in the CTO territory, independent of clinical, angiographic and procedural characteristics. Furthermore, lower baseline (hMBF: p&lt;0.01; CFR: p&lt;0.01) and higher post-PCI perfusion (hMBF: p&lt;0.01; CFR: p&lt;0.01) in both the remote and CTO territory were associated with larger perfusion increases in remote myocardium. Conclusions: Baseline and post-PCI perfusion indices in remote and CTO myocardium were positively correlated. An overall increase in remote myocardial perfusion was observed following CTO PCI and the absolute perfusion increase in the CTO territory was an independent predictor of remote myocardial perfusion improvement. Successful CTO PCI impacts coronary hemodynamics in the closely interlinked CTO and remote myocardium.

Predictive value of SPECT myocardial perfusion imaging in patients with unrevascularized coronary chronic total occlusion.

Data involved the association between myocardial ischaemia and the outcome for unrevascularized coronary chronic total occlusion (CTO) patients were limited. The purpose of this study was to evaluate the predictive value of ischaemia detected by single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) for the adverse events in unrevascularized CTO patients. We further explored whether ischaemia generated from CTO vessel can independently predict the outcome. Patients with at least one unrevascularized CTO on coronary angiography were enrolled in this study. Exercise stress/rest SPECT MPI was performed in all patients. All patients were then followed by telephone interview and reviewing of medical records. Patients with ischaemia experienced significantly higher rate of adverse events than non-ischaemia patients (40.7% vs 7.1%, P = 0.002). Ischaemia demonstrated on MPI [odds ratio (OR) = 7.656; 95% confidence interval (CI) 1.598-36.677; P = 0.011] was an independent predictor for adverse events. Moreover, CTO-ischaemia (OR = 5.466; 95% CI 1.015-29.420; P = 0.048), non-CTO ischaemia (OR = 29.174; 95% CI 3.245-262.322; P = 0.003), mixed-ischaemia (OR = 7.130, 95% CI 1.257-40.445; P = 0.027) were all independent predictors for outcome. Ischaemia demonstrated on MPI, especially CTO-ischaemia were independent predictors for the adverse events. SPECT MPI can aid to identify patients at risk of adverse events, who may benefit from subsequent CTO percutaneous coronary intervention.

The effect of chronic total coronary occlusion percutaneous coronary intervention on absolute perfusion in remote myocardium

Abstract Background Successful revascularization of a chronic total coronary occlusion (CTO) impacts coronary physiology of the remote myocardial territory. Purpose This study evaluated the effect of CTO percutaneous coronary intervention (PCI) on changes in absolute perfusion in remote myocardium as assessed by serial [15O]H2O positron emission tomography (PET) perfusion imaging. Methods A total of 164 patients underwent [15O]H2O PET imaging at baseline and 3 months after successful single-vessel revascularization of a CTO to evaluate changes in hyperemic myocardial blood flow (hMBF) and coronary flow reserve (CFR) in the remote myocardial territory supplied by both non-target coronary arteries. Results Remote hMBF and CFR improved (2.29±0.67 to 2.48±0.75 mL min–1 g–1 and 2.48±0.76 to 2.74±0.85, respectively) after CTO revascularization (p&amp;lt;0.01 for both). Absolute perfusion indices in the CTO vessel and the remote myocardium showed a positive linear correlation, both before (r=0.75, p&amp;lt;0.01 and r=0.77, p&amp;lt;0.01 for hMBF and CFR, respectively) and after (hMBF: r=0.87, p&amp;lt;0.01 and CFR: r=0.81, p&amp;lt;0.01) CTO PCI. Absolute increases in remote myocardial perfusion were largest in patients with a higher increase in hMBF (βeta [β] 0.56; 95% CI: 0.47–0.65; p&amp;lt;0.01) and CFR (β 0.51 (0.42–0.60); p&amp;lt;0.01) in the CTO territory, independent of clinical, angiographic and procedural characteristics. Furthermore, baseline (hMBF: β −0.24 (−0.39, −0.08); p&amp;lt;0.01 and CFR: β −0.26 (−0.41, −0.11); p&amp;lt;0.01) and post-PCI perfusion (hMBF: β 0.36; (0.27, 0.46); p&amp;lt;0.01 and CFR: β 0.30 (0.21, 0.40); p&amp;lt;0.01) in the CTO vessel were independently associated with the increase in remote myocardial perfusion after CTO PCI. Conclusions An overall increase in remote myocardial perfusion was observed following CTO PCI. Absolute perfusion indices in the remote myocardium showed a positive linear correlation with perfusion in the CTO vessel, before and after CTO revascularization. Importantly, baseline, post-PCI and the absolute increase in perfusion in the CTO territory were independently associated with increases in remote myocardial perfusion after revascularization. Funding Acknowledgement Type of funding sources: None. Figure 1Figure 2