Performance of J-CTO and PROGRESS CTO Scores in Predicting Angiographic Success and Long-term Outcomes of Percutaneous Coronary Interventions for Chronic Total Occlusions

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 follow up stent patency.

Impact of Selection Preference on Longer-Term Outcomes between Bioresorbable Vascular Scaffold versus Everolimus-Eluting Stent for True Lumen Tracking-Recanalized Chronic Total Occlusion

Creation of sizable subintima during intervention for chronic total occlusions (CTO) could lead to the key selection preference of metallic stents rather than bioresorbable vascular scaffolds (BVS) and then possibly deviate the outcome comparisons in real-world studies. By including recanalized CTO with true lumen tracking, we tested if any selection preference remained and compared the outcomes between everolimus-eluting stent (EES) and BVS implantation.Among 211 consecutive CTO interventions with true lumen tracking from August 2014 to April 2018 when BVS was available, we compared the clinical and interventional features between 28 patients with BVS and 77 patients with EES implantation. With propensity score matching and a median follow-up of 50.5 (37.3-60.3) months, we further assessed 25 patients with BVS and 25 with EES for target vessel failure (TVF: cardiac death, target vessel myocardial infarction, and target lesion revascularization).Multivariate analyses showed that BVS was still favored in the presence of LAD CTO (odds ratio (OR) = 3.4, 95% confidence interval (CI) = 1.0-11.7) and an average scaffold/stent size ≥ 3 mm (OR = 10.5, 95% CI = 3.0-37.3). EES was preferred for lesions with a J-CTO score ≥ 3 (OR = 19.3, 95% CI = 3.4-110.8) and multivessel intervention necessary at index procedure (OR = 11.3, 95% CI = 1.9-67.3). With matched comparisons, the TVF-free survival of EES was better than that of BVS for CTO recanalization (P = 0.049 by log-rank test) at long-term follow-up.Even with true lumen tracking techniques, selection bias remained substantial when determining either device for CTO implantation. The matched comparison of outcomes suggested the unfavorable longer-term impacts of the first generation of BVS on CTO lesions.

Impacts of Lesion Characteristics on Procedures and Outcomes of Chronic Total Occlusion Recanalization With Antegrade Guidewire True Lumen Tracking Techniques: A Substudy of Taiwan True Lumen Tracking Registry

Background

Lesion characteristics were shown to predict procedural success and outcomes in chronic total occlusion (CTO) recanalization. However, diverse techniques involved in these studies might cause potential heterogeneity.

Objective

The study aimed to test the impacts of lesion characteristics on CTO intervention with a pure antegrade wiring-based technique.

Methods and Results

We studied consecutive 325 patients (64.5 ± 11.1 years, 285 men) with native CTO lesions intervened by a single operator with an antegrade-based technique between August 2014 and July 2020. Forty-seven patients with antegrade procedural failure (20 with pure antegrade wiring failure and 27 with back-up retrograde techniques) were compared to 278 patients with antegrade-only procedural success. With a median follow-up of 30.8 (16.1–48.6) months, 278 patients with procedural success were further assessed for target vessel failure (TVF: cardiac death, target vessel myocardial infarction [MI], and target lesion revascularization [TLR]). Patients with antegrade procedural success had a lower percentage of history with bypass graft (4 vs. 15%, p = 0.004) and lower Multicenter Chronic Total Occlusion Registry of Japan (J-CTO) score (2.1±1.3 vs. 3.4 ± 1.0, p < 0.001), when compared to those with antegrade failure. The J-CTO score was independently associated with procedural failure (odds ratio = 2.5, 95% CI = 1.8–3.4) in multivariate analysis. However, only clinical features, such as female gender (hazard ratio [HR] = 4.3, 95% CI = 1.4–13.1), estimated glomerular filtration rate <60 ml/min/1.73 m² (HR = 3.2, 95% CI = 1.0–9.9), and old MI (HR = 4.5, 95% CI = 1.5–12.8), but not J-CTO score, could predict long-term TVF in multivariate Cox regression model.

Conclusion

The feasibility of the antegrade guidewire-crossing technique for native CTO intervention was highly determined by lesion characteristics. With such a simpler technique, the prognostic impact of lesion complexity shown in studies with multiple recanalization techniques was negligible. This suggested antegrade true lumen tracking techniques deserved to be tried better even for CTO lesions with higher complexity.

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

Background

The 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).

Methods

A 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.

Conclusion

Compared 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.

Impact of diabetes mellitus on outcomes of percutaneous coronary intervention in chronic total occlusions: A systematic review and meta-analysis

BACKGROUND

Patients with diabetes mellitus (DM) have a high prevalence of coronary chronic total occlusions (CTOs). We conducted a systematic review and meta-analysis to characterize outcomes after CTO percutaneous coronary intervention (PCI) in patients without or with DM.

METHODS

PubMed, EMBASE, Cochrane, and Google Scholar were queried for studies comparing non-DM vs. DM patients undergoing attempted CTO PCI. The primary outcome was all-cause mortality at longest follow-up (at least 6 months). Secondary outcomes were major adverse cardiovascular events (MACE) which is a composite endpoint including myocardial infarction, cardiac or all-cause mortality and any revascularization in patients after CTO PCI, target vessel revascularization (TVR), myocardial infarction (MI), Japanese chronic total occlusion (J-CTO) score and prevalence of multivessel (MV) CTO disease. We used a random effects model to calculate odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Sixteen studies, including 2 randomized control trials and 14 observational studies, met inclusion criteria. At longest follow-up, all-cause mortality (OR 0.54 [95% CI 0.37-0.80], p < 0.0001) and MACE (OR 0.82 [95% CI 0.72-0.93], p < 0.00001) were significantly lower in non-DM CTO patients. MV CTO disease was less prevalent in patients without DM (OR 0.80 [95% CI 0.69-0.93], p = 0.004). However, there were no differences in MI, TVR and J-CTO score.

CONCLUSIONS

Non-diabetics undergoing CTO PCI have lower all-cause mortality and MACE than diabetics. Future research may determine if DM control improves diabetics' CTO PCI outcomes.

The impact of successful chronic total occlusion percutaneous coronary intervention on long-term clinical outcomes in real world

BACKGROUND

Coronary chronic total occlusions (CTOs) are related to increased risk of adverse clinical outcomes. The optimal treatment strategy for CTO has not been well established. We sought to examine the impact of CTO percutaneous coronary intervention (PCI) on long-term clinical outcome in the real world.

METHODS

A total of 592 patients with CTO were enrolled. 29 patients were excluded due to coronary artery bypass grafting (CABG). After exclusion, 563 patients were divided into the no-revascularized group (CTO-NR group, n = 263) and successful revascularized group (CTO-R group, n = 300). The primary endpoint was cardiac death; secondary endpoint was major adverse cardiac and cerebrovascular events (MACCE), a composite of all-cause death, cardiac death, recurrent myocardial infarction, target lesion revascularization, re-hospitalization, heart failure, and stroke.

RESULTS

Percent of Diabetes mellitus (53.2% vs 39.7), Chronic kidney disease (8.7% vs 3.7%), CABG history (7.6% vs 1%), three vessel disease (96.2% vs 90%) and left main coronary artery disease (25.1% vs 13.7%) was significantly higher in the CTO-NR group than in success PCI group (all P < 0.05). Moreover, the CTO-NR group has the lower ejection fraction (EF) (0.58 ± 0.11 vs 0.61 ± 0.1, p = 0.001) and fraction shortening (FS) (0.31 ± 0.07 vs 0.33 ± 0.07, p = 0.002). At a median follow-up of 12 months, CTO revascularization was superior to CTO no-revascularization in terms of cardiac death (adjusted hazard ratio [HR]: 0.27, 95% conference interval [CI] 0.11-0.64). The superiority of CTO revascularization was consistent for MACCE (HR: 0.55, 95% CI 0.35-0.79). At multivariable Cox hazards regression analysis, CTO revascularization remains one of the independent predictors of lower risk of cardiac death and MACCE.

CONCLUSIONS

Successful revascularization by PCI may bring more clinical benefits. The presence of low left ventricular ejection fraction (LVEF) and LM-disease was associated with an incidence of cardiac death; CTO revascularization was a protected predictor of cardiac death. Successful revascularization by PCI offered CTO patients more clinical benefits, manifested by lower incidence of cardiac death during follow-up. The presence of LVEF < 0.5 and left main coronary artery disease (LM disease) was associated with an incidence of cardiac death; CTO revascularised was a protected predictor of cardiac death.

Randomized Controlled Comparison of Optimal Medical Therapy with Percutaneous Recanalization of Chronic Total Occlusion (COMET-CTO)

The aim of this randomized prospective study was to evaluate the quality of life (QoL) using the "Seattle Angina Questionnaire" (SAQ) in patients with chronic total occlusion (CTO) in coronary arteries treated with either percutaneous coronary intervention (PCI) or optimal medical therapy (OMT), or only with OMT.The potential benefits of recanalization of CTO by PCI have been controversial because of the scarcity of randomized controlled trials.A total of 100 patients with CTO were randomized (1:1) prospectively into the PCI CTO or the OMT group (50 patients in each group). There were no baseline differences in the SAQ scores between the groups, except for physical limitation scores (P = 0.03). During the mean follow-up (FUP) of 275 ± 88 days, patients in the PCI group reported less physical activity limitations (72.7 ± 21.3 versus 60.5 ± 27, P = 0.014), less frequent angina episodes (89.8 ± 17.6 versus 76.8 ± 27.1, P = 0.006), better QoL (79.9 ± 22.7 versus 62.5 ± 25.5, P = 0.001), greater treatment satisfaction (91.2 ± 13.6 versus 81.4 ± 18.4, P = 0.003), and borderline differences in angina stability (61.2 ± 26.5 versus 51.0 ± 23.7, P = 0.046) compared to patients in the OMT group. There were no significant differences in SAQ scores in the OMT group at baseline and during the FUP. There was a statistically significant increase in all five domains in the PCI group.Symptoms and QoL measured by the SAQ were significantly improved after CTO PCI compared to OMT alone.

The CTo-aBCDE score: A new predictor of success in chronic total occlusions

INTRODUCTION

Patient selection for percutaneous coronary intervention (PCI) in chronic total occlusions (CTOs) is crucial to procedural success. Our aim was to identify independent predictors of success in CTO PCI in order to create an accurate score.

METHODS

In a single-center observational registry of CTO PCI, demographic and clinical data and anatomical characteristics of coronary lesions were recorded. Linear and logistic regression analysis were used to identify predictors of success. A score to predict success was created and its accuracy was measured by receiver operating curve analysis.

RESULTS

A total of 377 interventions were performed (334 patients, age 68±11 years, 75% male). The success rate was 65% per patient and 60% per procedure. Predictors of success in univariate analysis were absence of active smoking (OR 2.02, 95% CI 1.243-3.29; p=0.005), presence of tapered stump (OR 5.2, 95% CI 2.7-10.2; p<0.001), absence of tortuosity (OR 6.44; 95% CI 3.02-13.75; p<0.001), absence of bifurcation (OR 1.95; 95% CI 1.08-3.51; p=0.026), absence of calcification (OR 3.1; 95% CI 3.10-5.41; p<0.001), LAD as target vessel (OR 1.9, 95% CI 1.0-3.5; p=0.048), and CTO length <20 mm (OR 3.00, 95% CI 1.69-5.3; p<0.001). Only anatomical factors were independent predictors of success, and an anatomical score (0-11 points) with high accuracy (area under the curve 0.831) was subsequently created. A score <3 was associated with low probability of success (15%), 3-8 with intermediate probability (55%), and >8 with high probability (95%).

CONCLUSION

In our sample only anatomical characteristics were predictors of success. The creation of a score to predict success, with good accuracy, may enable selection of cases that can be treated by any operator, those in which a dedicated operator will be desirable, and those with an extremely low probability of success, which should be considered individually for conservative management, surgical revascularization or PCI by a team experienced in CTO.

Derivation and validation of the J-CTO extension score for pre-procedural prediction of major adverse cardiac and cerebrovascular events in patients with chronic total occlusions

We developed a prediction model of long-term risk after percutaneous coronary intervention (PCI) for coronary chronic total occlusion (CTO) based on pre-procedural clinical information. A total of 4,139 eligible patients, who underwent CTO-PCI at 52 Japanese centers were included. Specifically, 1,909 patients with 1-year data were randomly divided into the derivation (n = 1,273) and validation (n = 636) groups. Major adverse cardiac and cardiovascular event (MACCE) was the primary endpoint, including death, stroke, revascularization, and non-fatal myocardial infarction. We assessed the performance of our model using the area under the receiver operating characteristic curve (AUC) and assigned a simplified point-scoring system. One-hundred-thirty-eight (10.8%) patients experienced MACCE in the derivation cohort with hemodialysis (HD: odds ratio [OR] = 2.55), left ventricular ejection fractions (LVEF) <35% (OR = 2.23), in-stent occlusions (ISO: OR = 2.27), and diabetes mellitus (DM: OR = 1.72). The AUC of the derivation model was 0.650. The model’s performance was similar in the validation cohort (AUC, 0.610). When assigned a point for each associated factor (HD = 3, LVEF <35%, ISO = 2, and DM = 1 point), the average predicted versus the observed MACCE probability using the Japan-CTO extension score for the low, moderate, high, and very high risk groups was 8.1% vs. 7.3%, 16.9% vs. 15.9%, 22.0% vs. 26.1%, and 56.2% vs. 44.4%, respectively. This novel risk model may allow for the estimation of long-term risk and be useful in disseminating appropriate revascularization procedures.

In-hospital outcomes of chronic total occlusion percutaneous coronary intervention in patients with and without prior coronary artery bypass graft: A protocol for systematic review and meta analysis

The clinical outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) in prior coronary artery bypass graft (pCABG) patients have been investigated; however, the results are inconsistent.The present meta-analysis compared the clinical outcomes of CTO PCI in patients with and without prior CABG (nCABG). The endpoints included technical success, procedural success, all-cause mortality, myocardial infarction (MI), major bleeding, coronary perforation, pericardial tamponade, emergency CABG, and vascular access complication.A total of 7 studies comprising of 11099 patients were included in this meta-analysis. The results showed that compared to nCABG patents, pCABG patients were associated with lower technical success (82.3% versus 87.8%; OR, 0.60; 95% CI, 0.53-0.68; P < .00001; I = 0%) and procedural success (80.4% versus 86.2%; OR, 0.61; 95% CI, 0.53-0.70; P < .00001; I = 10%); a higher risk of all-cause mortality (OR, 2.95; 95% CI, 1.56-5.57; P = 0.0008; I = 0%), MI (OR, 2.30; 95% CI, 1.40-3.80; P = .001; I = 5%), and coronary perforation (OR, 2.16; 95% CI, 1.51-3.08; P < 0.0001; I = 52%). On the other hand, the risk of pericardial tamponade (OR, 0.42; 95% CI, 0.15-1.18; P = .10; I = 21%), major bleeding (OR, 1.51; 95% CI, 0.90-2.53; P = .11; I = 0%), vascular access complication (OR, 1.50; 95% CI, 0.93-2.41; P = .10; I = 0%), and emergency CABG (OR, 0.99; 95% CI, 0.25-3.91; P = .99; I = 0%) was similar in both groups.Compared to nCABG patients, pCABG patients had lower CTO PCI success rates, higher rates of in-hospital mortality, MI, and coronary perforation, and similar risk of pericardial tamponade and vascular complication rates.

Average daily ischemic versus bleeding risk in patients with ACS undergoing PCI: Insights from the BleeMACS and RENAMI registries

BACKGROUND

The risk of recurrent ischemia and bleeding after percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) may vary during the first year of follow-up according to clinical presentation, and medical and interventional strategies.

METHODS

BleeMACS and RENAMI are 2 multicenter registries enrolling patients with ACS treated with PCI and clopidogrel, prasugrel, or ticagrelor. The average daily ischemic and bleeding risks (ADIR and ADBR) in the first year after PCI were the primary end points. The difference between ADBR and ADIR was calculated to estimate the potential excess of bleeding/ischemic events in a given period or specific subgroup.

RESULTS

A total of 19,826 patients were included. Overall, in the first year after PCI, the ADBR was 0.008085%, whereas ADIR was 0.008017% (P = .886). In the first 2 weeks ADIR was higher than ADBR (P = .013), especially in patients with ST-segment elevation myocardial infarction or incomplete revascularization. ADIR continued to be, albeit non-significantly, greater than ADBR up to the third month, whereas ADBR became higher, although not significantly, afterward. Patients with incomplete revascularization had an excess in ischemic risk (P = .003), whereas non-ST-segment elevation ACS patients and those on ticagrelor had an excess of bleeding (P = .012 and P = .022, respectively).

CONCLUSIONS

In unselected ACS patients, ADIR and ADBR occurred at similar rates within 1 year after PCI. ADIR was greater than ADBR in the first 2 weeks, especially in ST-segment elevation myocardial infarction patients and those with incomplete revascularization. In the first year, ADIR was higher than ADBR in patients with incomplete revascularization, whereas ADBR was higher in non-ST-segment elevation ACS patients and in those discharged on ticagrelor.

Predictors for Target Vessel Failure after Recanalization of Chronic Total Occlusions in Patients Undergoing Surveillance Coronary Angiography

(1) Background: Knowledge about predictors for the long-time patency of recanalized chronic total coronary occlusions (CTOs) is limited. Evidence from invasive follow-up in the absence of acute coronary syndrome (routine surveillance coronary angiography) is scarce. (2) Methods: In a monocentric-retrospective analysis, we obtained baseline as well as periprocedural data of patients undergoing routine invasive follow-up. We defined target vessel failure (TVF) as a combined primary endpoint, consisting of re-occlusion, restenosis, and target vessel revascularization (TVR). (3) Results: We included 93 consecutive patients (15.1% female) from October 2013 to May 2018. After a follow-up period of 206 ± 129 days (median 185 (IQR 127–237)), re-occlusion had occurred in 7.5%, restenosis in 11.8%, and TVR in 5.4%; the cumulative incidence of TVF was 15.1%. Reduced TIMI-flow immediately after recanalization (OR for TVR: 11.0 (95% CI: 2.7–45.5), p = 0.001) as well as female gender (OR for TVR: 11.0 (95% CI: 2.1–58.5), p = 0.005) were found to be predictive for pathological angiographic findings at follow-up. Furthermore, higher blood values of high-sensitive troponin after successful revascularization were associated with all endpoints. Interestingly, neither the J-CTO score nor the presence of symptoms at the follow-up visit could be correlated to adverse angiographic results. (4) Conclusions: In this medium-sized cohort of patients with surveillance coronary angiography, we were able to identify reduced TIMI flow and female gender as the strongest predictors for future TVF.

The Impact of Peripheral Artery Disease in Chronic Total Occlusion Percutaneous Coronary Intervention (Insights From PROGRESS-CTO Registry)

The impact of peripheral artery disease (PAD) in patients undergoing chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has received limited study. We reviewed 3999 CTO PCIs performed in 3914 patients between 2012 and 2018 at 25 centers, 14% of whom had a history of PAD. We compared the clinical and angiographic characteristics and procedural outcomes of patients with versus without history of PAD. Patients with PAD were older (67 ± 9 vs 64 ± 10 years, P < .001) and had a higher prevalence of cardiovascular risk factors. They also had more complex lesions as illustrated by higher Japanese CTO score (2.7 ± 1.2 vs 2.4 ± 1.3, P < .001). In patients with PAD, the final crossing technique was less often antegrade wire escalation (40% vs 51%, P < .001) and more often the retrograde approach (23 vs 20%, P < .001) and antegrade dissection/reentry (20% vs 16%, P < .001). Technical success was similar between the 2 study groups (84% vs 87%, P = .127), but procedural success was lower for patients with PAD (81% vs 85%, P = .015). The incidence of in-hospital major adverse cardiac events was higher among patients with PAD (3% vs 2%, P = .046). In conclusion, patients with PAD undergoing CTO PCI have more comorbidities, more complex lesions, and lower procedural success.

When the Complex Meets the High-Risk: Mechanical Cardiac Support Devices and Percutaneous Coronary Interventions in Severe Coronary Artery Disease

Coronary artery disease (CAD) remains a leading cause of mortality and morbidity worldwide. Few practice guidelines directly address the issue of revascularization in patients with CAD at higher risk of periprocedural complications. It remains a challenge to appropriately identify the subset of patients with CAD who will require short-term use of mechanical cardiocirculatory support devices (MCSDs) when high-risk (HR) percutaneous coronary intervention (PCI) is required. Issues of the complexity (coronary anatomy and high burden of comorbidities) and risk status (hemodynamic precarity or compromise) need to be considered when considering revascularization in patients. This review will focus on the evolving concept of protected PCI in patients with CAD, and how a balanced, integrated heart-team approach remains the path to optimal patient-centred care in the setting of HR-PCI supported with MCSD.

Contemporary Approach to Chronic Total Occlusion Interventions

PURPOSE OF REVIEW

Chronic total occlusion (CTO) poses one of the greatest technical challenges to interventional cardiologists. Despite recent advancements in techniques and clinical trials showing significant benefits of CTO percutaneous coronary interventions (PCI), the proportion of patients with untreated CTOs remains high. We therefore aim to perform a comprehensive review of the various techniques available, recent advancements, benefits, and complications associated with CTO PCI.

RECENT FINDINGS

Three randomized clinical trials examining the benefits of CTO PCI have recently been presented. Scoring systems have been developed to facilitate pre-procedural estimation of success and complications of CTO PCI. Technological enhancements in coronary wires and other interventional equipment along with dedicated training for CTO operators have improved the likelihood of successful recanalization of CTOs. CTO PCI has been shown to improve patient symptoms and quality of life. It is therefore important to have an in-depth knowledge of the various CTO techniques, appropriate equipment, and complications when performing these complex procedures. Clinicians should weigh the risks and benefits and choose the appropriate patient population who may benefit from revascularization.