Percutaneous coronary intervention of chronic total occlusion (CTO PCI) is a challenging procedure with high complication rates and, as not yet fully understood long-term clinical benefits. Ischemic symptom relief in patients with high ischemic burden is to date the only established clinical indication to undergo CTO PCI, supported by randomized controlled trials. In this context, current guidelines suggest attempting CTO PCI only in non-invasively assessed viable CTO correspondent myocardial territories, with large ischemic areas. Hence, besides a comprehensive coronary angiography lesion evaluation, the information derived from non-invasive cardiac imaging techniques is crucial to selecting candidates who may benefit from the revascularization of the occluded vessel. Currently, there are no clear recommendations for a non-invasive myocardial evaluation or choice of imaging modality pre-CTO PCI. Therefore, selecting among available options is left to the physician’s discretion. As CTO PCI is strongly recommended to be carried out explicitly in experienced centers, full access to non-invasive imaging for risk-benefit assessment as well as a systematic institutional evaluation process has to be encouraged. In this framework, we opted to review the current myocardial imaging tools and their use for indicating a CTO PCI. Furthermore, based on our experience, we propose a cost-effective systematic approach for myocardial assessment to help guide clinical decision-making for patients presenting with chronic total occlusions.

Introduction: Percutaneous coronary intervention (PCI) for chronic total occlusions (CTOs) requires advanced techniques and prolonged procedural efforts, often necessitating high contrast volumes, which may increase the risk of contrast-associated acute kidney injury (CA-AKI). However, evidence suggests that factors beyond contrast exposure contribute to CA-AKI, though data specific to CTO PCI remain limited. Methods: Patients undergoing contemporary CTO PCI at our university-affiliated tertiary care center were enrolled. CA-AKI was defined according to KDIGO criteria, and patients were stratified based on the presence of postprocedural CA-AKI. Baseline and procedural characteristics, including osmotic factors, were compared between the groups. The primary outcome was all-cause mortality at one year, and the secondary outcome was all-cause mortality at three years. Results: A total of 145 patients were enrolled, with a mean age of 67 years, and 75% were male. Baseline creatinine levels, electrolytes, and osmotic factors did not differ significantly between groups. Lesion parameters and J-CTO scores were also comparable. The contrast volume and procedural duration were numerically higher in patients who developed CA-AKI. Patients with CA-AKI received a higher radiation dose (22.1 vs. 13.2 Gy·cm², p = 0.041). CA-AKI emerged as an independent predictor of all-cause mortality at one year (adjusted HR 5.3, CI [1.52–18.51], p = 0.009) but not at three years. Conclusions: In this retrospective analysis, CA-AKI was an independent predictor of all-cause mortality at one year following CTO PCI but lost predictive value at three years. Baseline renal function and contrast volume alone did not predict CA-AKI. Instead, procedural complexity, reflected by higher radiation exposure, was associated with an elevated risk of CA-AKI.

Background: Percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) remains a complex procedure that requires advanced operator skills and dedicated devices. Despite increased success rates in experienced centers, the in-hospital complications of CTO PCI remain notably high. Female patients undergoing CTO PCI are reported to experience higher rates of complications; however, the underlying mechanisms remain inadequately defined. Methods: We prospectively enrolled consecutive patients undergoing CTO PCI at our university-affiliated tertiary care center over 4 years (2018–2021), aiming to elucidate sex-based disparities in in-hospital complications. In addition, we investigated the impact of angiographic femoral artery metrics on in-hospital complications. Results: Among 271 patients who underwent antegrade or retrograde CTO PCI, 222 (81.9%) were men and 49 (18.9%) women. Female patients were significantly older (67 ± 11 vs. 72 ± 12 years; p = 0.005) and had a comparable lesion complexity. Women exhibited smaller femoral artery diameters, more side branches at the puncture area and higher bifurcations. In-hospital complications occurred more frequently in women compared to men (16.3% vs. 6.8%; p = 0.044). Female sex independently predicted in-hospital complications (OR = 2.92; CI 1.07 to 7.60; p = 0.024), yet lost significance after adjustment for femoral artery characteristics. Maximal femoral artery diameter (OR = 0.30, 95% CI: 0.17 to 0.50, p < 0.001) and side-branch density (OR = 2.45, 95% CI: 1.26 to 5.20, p = 0.012) independently predicted in-hospital complications. Conclusions: Female patients undergoing CTO PCI are at increased risk for procedural complications, likely driven by femoral artery anatomical differences. Detailed pre-procedural assessment of femoral artery metrics may improve patient selection, procedural planning, and outcomes, particularly among women.