The Hybrid Algorithm for Treating Chronic Total Occlusions in Europe

On-line estimated peak skin dose during percutaneous coronary intervention for chronic total occlusion using new patient dose mapping technology

BACKGROUND

X-ray exposure during complex percutaneous coronary intervention is a very important issue.

AIM

To reduce patient peak skin dose during percutaneous coronary intervention procedures for chronic total occlusion using on-line estimated peak skin dose software (Dose Map).

METHODS

Throughout the procedure, Dose Map provided a map of local cumulative peak skin dose. This map was displayed in-room from 1Gy cumulative air kerma, and was updated every 0.5Gy. The operator's actions to minimize deterministic risks following map notification were collected. Skin reaction was evaluated 3 months after the procedure. A comparison with our historical X-ray exposure data (207 patients from January 2013 to July 2014) was performed.

RESULTS

From November 2015 to October 2016, 97 patients (Japanese chronic total occlusion score 2.1±1.1; 100 percutaneous coronary intervention procedures for chronic total occlusion) were prospectively enrolled. Fluoroscopy time was 40.8 (21.6-60.3) minutes, cumulative air kerma 1884 (1144-3231) mGy, estimated peak skin dose 962 (604-1474) mGy and kerma area product 115.8 (71.5-206.7) Gy.cm². Cumulative air kerma was>3Gy in 28% of cases, and>5Gy in 11% of cases. In 68% of cases, at least one action was taken by the operator after map notification to optimize skin dose distribution. Main changes included: gantry angulation (52%); field of view (25%); and collimation (13%). No skin injuries were observed at follow-up. In comparison with our chronic total occlusion historical radiation data, median cumulative air kerma and kerma area product were reduced by 31% and 33%, respectively (P<0.005.

CONCLUSION

Online skin dose mapping software allows the distribution of patient skin dose during complex percutaneous coronary intervention procedures, and may minimize X-ray exposure.

Safety and feasibility of transradial access for percutaneous coronary intervention in chronic total occlusions

INTRODUCTION AND OBJECTIVES

Transfemoral access is the most frequently used vascular approach in chronic total occlusion percutaneous coronary interventions (CTO-PCI). The aim of this study was to evaluate the safety and feasibility of a transradial access CTO-PCI program and its impact on angiographic and clinical results and length of hospital stay.

METHODS

Retrospective multicenter cohort study including 2550 consecutive CTO-PCI procedures included in a multicenter registry with accurate information on vascular access. A total of 896 procedures were performed as radial-only access while 1654 were performed through at least 1 femoral puncture. Clinical and angiographic data were collected.

RESULTS

The mean age was 66.3± 11.4 years. The mean Japan-chronic total occlusion score (2.7±0.3) was similar in the 2 groups. Successful revascularization was achieved in 2009 (79.6%) cases, 78.2% and 82.1% in the femoral and radial access cohorts, respectively (P=.002). Periprocedural in-hospital complications were observed in 5.1% and 2.3% (P=.02), with fewer access site-dependant vascular complications in the transradial cohort (2.3% vs 0.2%; P=.009). The mean length of hospital stay was significantly shorter in the transradial access group (0.89±1.4 vs 2.2±3.2 days, P<.001).

CONCLUSIONS

A transradial program for CTO-PCI is safe and effective in most CTO lesions. The transradial strategy has fewer vascular complications and shorter length of hospital stay without compromising the success rate.

Predictors of success in primary retrograde strategy in chronic total occlusion percutaneous coronary intervention: insights from the PROGRESS-chronic total occlusion registry

BACKGROUND

An upfront (primary) retrograde strategy is often used in complex chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

METHODS

We examined the clinical, angiographic characteristics, and procedural outcomes of CTO PCIs that were approached with a primary retrograde strategy in the Prospective Global Registry for the Study of CTO Intervention (PROGRESS-CTO, NCT02061436).

RESULTS

Of 10,286 CTO PCIs performed between 2012 and 2022, a primary retrograde strategy was used in 1329 (13%) with an initial technical success of 66%, and a final success of 83%. Patients who underwent successful versus unsuccessful primary retrograde cases had similar characteristics: age (65 ± 10 vs. 65 ± 9, years, p = 0.203), men (83% vs. 87%, p = 0.066), prior PCI (71% vs. 71%, p = 0.809), and prior coronary artery bypass graft surgery (52% vs. 53%, p = 0.682). The PROGRESS-CTO score (1.3 ± 0.9 vs. 1.6 ± 0.9, p < 0.001), air kerma radiation (3.9 ± 2.8 vs. 3.4 ± 2.6, gray, p = 0.013), and contrast use (294 ± 148 ml vs. 248 ± 128, ml, p < 0.001) were higher in the unsuccessful group, whereas the presence of interventional collaterals (95% vs. 72%, p < 0.001) and Werner collateral connection grade 2 (43% vs. 31%, p < 0.001) were higher in the successful group. On multivariable logistic regression analysis, the only variable associated with a successful primary retrograde strategy was the presence of interventional collaterals: odds ratio: 6.52 (95% confidence intervals; 3.5-12.1, p < 0.001).

CONCLUSION

Presence of interventional collaterals is independently associated with higher success rates with a primary retrograde strategy in CTO PCI.

Predicting Residual Angina After Chronic Total Occlusion Percutaneous Coronary Intervention: Insights from the OPEN-CTO Registry

Background Given that percutaneous coronary intervention (PCI) of a chronic total occlusion (CTO) is indicated primarily for symptom relief, identifying patients most likely to benefit is critically important for patient selection and shared decision-making. Therefore, we identified factors associated with residual angina frequency after CTO PCI and developed a model to predict postprocedure anginal burden. Methods and Results Among patients in the OPEN-CTO (Outcomes, Patient Health Status, and Efficiency in Chronic Total Occlusion Hybrid Procedures) registry, we evaluated the association between patient characteristics and residual angina frequency at 6 months, as assessed by the Seattle Angina Questionnaire Angina Frequency Scale. We then constructed a prediction model for angina status after CTO PCI using ordinal regression. Among 901 patients undergoing CTO PCI, 28% had no angina, 31% had monthly angina, 30% had weekly angina, and 12% had daily angina at baseline. Six months later, 53% of patients had a ≥20-point increase in Seattle Angina Questionnaire Angina Frequency Scale score. The final model to predict residual angina after CTO PCI included baseline angina frequency, baseline nitroglycerin use frequency, dyspnea symptoms, depressive symptoms, number of antianginal medications, PCI indication, and presence of multiple CTO lesions and had a C index of 0.78. Baseline angina frequency and nitroglycerin use frequency explained 71% of the predictive power of the model, and the relationship between model components and angina improvement at 6 months varied by baseline angina status. Conclusions A 7-component OPEN-AP (OPEN-CTO Angina Prediction) score can predict angina improvement and residual angina after CTO PCI using variables commonly available before intervention. These findings have implications for appropriate patient selection and counseling for CTO PCI.

Femoral or Radial Approach in Treatment of Coronary Chronic Total Occlusion: A Randomized Clinical Trial

OBJECTIVES

The aim of this study was to compare transradial access (TRA) with transfemoral access (TFA) for chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

BACKGROUND

TRA reduces the risk for vascular access complications but may make complex PCI, such as CTO PCI, more challenging.

METHODS

FORT CTO (Femoral or Radial Approach in the Treatment of Coronary Chronic Total Occlusion) (NCT03265769) was a prospective, noninferiority, randomized controlled study of TRA vs TFA for CTO PCI. The primary study endpoint was procedural success, defined as technical success without any in-hospital major adverse cardiovascular events. The secondary study endpoint was major access-site complications.

RESULTS

Between 2017 and 2021, 610 of 800 patients referred for CTO PCI at 4 centers were randomized to TRA (n = 305) or TFA (n = 305). Mean J-CTO (Multicenter CTO Registry in Japan) (2.1 ± 0.1 vs 2.2 ± 0.1; P = 0.279), PROGRESS CTO (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention) (1.3 ± 0.9 vs 1.1 ± 1.0; P = 0.058) and PROGRESS CTO complication (2.4 ± 1.8 vs 2.3 ± 1.8; P = 0.561) scores and use of the retrograde approach (11% vs 14%; P = 0.342) were similar in the TRA and TFA groups. TRA was noninferior to TFA for procedural success (84% vs 86%; P = 0.563) but had fewer access-site complications (2.0% vs 5.6%; P = 0.019). There was no difference between TFA and TRA in procedural duration, contrast volume, or radiation dose.

CONCLUSIONS

TRA was noninferior to TFA for CTO PCI but had fewer access-site complications.

Accuracy of the Euro CTO(CASTLE) score obtained on coronary computed tomography angiography for Predicting 30-minute wire crossing in chronic total occlusions

Background

To investigate the feasibility and accuracy of the Euro CTO (CASTLE)_CTA score obtained on coronary computed tomography angiography (CCTA) for predicting the success of percutaneous coronary intervention (PCI) and the 30-min wire crossing in chronic total occlusions (CTO).

Method

One hundred and fifty patients (154 CTO cases; median age, 61 (interquartile range [IQR], 54–68) years; 75.3% male) received CCTA at the People's Hospital of Liaoning Provincce within 1 month before the procedure. The Euro CTO (CASTLE) score obtained on CCTA(CASTLE_CTA) was calculated and compared with the Euro CTO (CASTLE) score obtained based on coronary angiography (CASTLE_CAG) for the predictive value of 30-min wire crossing and CTO procedural success.

Results

In our study, the CTO-PCI success rate was 89.0%, with guidewires of 65 cases (42.2%) crossing within 30 min. There were no significant differences in the median CASTLE_CTA and CASTLE_CAG scores in the procedure success group (3 [IQR, 2–4] vs 3 (IQR, 2–3]; p = 0.126). However, the median CASTLE_CTA score was significantly higher than the median CASTLE_CAG score in the procedure failure group (4 [IQR, 3–5.5] vs 4 [IQR, 2.5–5.5]; p = 0.021). There was no significant difference between the median CASTLE_CTA score and the median CASTLE_CAG score in the 30-min wire crossing failure group (3 [IQR, 3–4] vs 3 [IQR, 2–4]; p = 0.254). However, the median CASTLE_CTA score was significantly higher than the median CASTLE_CAG score in the 30-min wire crossing group (3 [IQR, 2–3] vs 2 [IQR, 2–3]; p < 0.001). The CASTLE_CTA score described higher levels of calcification than the CASTLE_CAG score (48.1% vs 33.8%; p = 0.015). There was no significant difference between the CASTLE_CTA score (area under the curve [AUC], 0.643; 95% confidence interval [CI], 0.561–0.718) and the CASTLE_CAG score (AUC, 0.685; 95% CI, 0.606–0.758) for predicting procedural success (p = 0.488). The CASTLE_CTA score (AUC, 0.744; 95% CI, 0.667–0.811) was significantly better than the CASTLE_CAG score (AUC, 0.681; 95% CI, 0.601–0.754; p = 0.046) for predicting 30-min wire crossing with the best cut-off value being CASTLE_CTA ≤ 3. The sensitivity, specificity, positive predictive value, and negative predictive value were 90.8%, 55.2%, 54.6%, and 87.0%, respectively.

Conclusion

The CASTLE_CTA scores obtained from noninvasive CCTA perform better for the prediction of the 30-min wire crossing than the CASTLE_CAG score.

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.

PCI in Patients With Heart Failure: Current Evidence, Impact of Complete Revascularization, and Contemporary Techniques to Improve Outcomes

Coronary artery disease (CAD) is the most common cause of left ventricular systolic dysfunction (LVSD) and heart failure (HF). Revascularization with coronary artery bypass grafting (CABG) reduces all-cause mortality compared with medical therapy alone for these patients. Despite this, CABG is performed in a minority of patients with HF, partly due to patient unwillingness or inability to undergo major cardiac surgery and partly due to physician reluctance to refer for surgery due to high operative risk. Percutaneous coronary intervention (PCI) is a less-invasive method of revascularization that has the potential to reduce periprocedural complications compared with CABG in patients with HF. Recent advances in PCI technology and technique have made it realistic to achieve more complete revascularization with PCI in high-risk patients with HF, although no randomized controlled clinical trials (RCTs) of PCI in HF compared with either medical therapy or CABG have been performed. In this review, we discuss the currently available evidence for PCI in HF and the association between the extent of revascularization and clinical outcomes in HF. We also review recent advances in PCI technology and techniques with the potential to improve clinical outcomes in HF. Finally, we discuss emerging clinical trial evidence of revascularization in HF and the large, persistent evidence gaps that should be addressed with future clinical trials of revascularization in HF.

A novel use of small ballons to reduce the risk of subintimal hematoma formation during recanalization of chronic total occlusion: two case reports

Background

Subintimal hematoma remains a major challenge associated with unnecessary technical complexity, failure of the antegrade approach or imperfection of revascularization in percutaneous coronary intervention (PCI) for chronic total occlusion (CTO). Some techniques and devices release the hematoma after its formation. Here, we describe a novel use of small ballons to prevent the hematoma formation during antegrade approach in two cases.

Case presentation

We report two cases of CTO-PCI in which balloon occlusion was successfully applied to prevent haematoma formation. The first case, a 72-year-old female with diabetes, was hospitalized because of unstable angina. Angiography showed right coronary artery (RCA) CTO, which initiated from the proximal part to the trifurcation at the distal part of the RCA. Considering the high likelihood and serious consequences of subintimal haematoma, a small balloon is employed to prevent subintimal hematoma formation. A balloon and microcatheter or double-lumen microcatheter are placed in the proximal coronary CTO lesion; then the balloon was dilated beside the catheter, most of the antegrade blood flow was sealed which reduced the likelihood of haematoma formation. The procedure was successfully completed without subintimal hematoma formation. The second case a 62-year-old male with unstable angina, was hospitalized for PCI. Angiography showed left anterior descending coronary artery CTO. Similar to case 1, we also used a small balloon to prevent hematoma formation. Both patients underwent PCI, which employed a small balloon to prevent hematoma formation and both procedures were successful without complications.

Conclusion

In patients who underwent CTO-PCI, balloon occlusion offers an alternative for reducing the incidence of subintimal haematomas.

Operator experience and clinical outcomes of percutaneous coronary intervention for chronic total occlusion: insights from a pooled analysis of the Japanese CTO PCI Expert Registry and the Retrograde Summit General Registry

There have not been enough studies to examine the association between difference in operator experience and technical success rate in contemporary percutaneous coronary intervention for chronic total occlusion (CTO-PCI). The present study sought to provide insights into the impact of operator experience on clinical outcomes of CTO-PCI through a comparison of two largest Japanese CTO-PCI registries consisting of operators with different CTO-PCI experience. After combining clinical data from the Japanese CTO-PCI Expert Registry (ER) 2014-2016 (N = 4316) including CTO-PCI performed by highly experienced operators and the Retrograde Summit General Registry (RSGR) 2014-2016 (N = 2230) including CTO-PCI performed by less experienced operators, a pooled analysis was performed to compare clinical outcomes of CTO-PCI in 2 registries. The overall technical success rate and the incidence of in-hospital major adverse events were comparable between ER and RSGR (90.1% vs 88.9%, p = 0.133, 1.7% vs 1.5%, p = 0.606, respectively). Technical success rate in ER was significantly higher among the patients treated with primary antegrade approach (91.8% vs 89.5%, p = 0.009), whereas there was no significant difference among the patients treated with the primary retrograde approach (85.7% vs 85.3%, p = 0.857). Multivariate analysis suggested ER operator could not be an independent predictor for technical success. CTO-PCI performed by less experienced but appropriately trained operators could achieve similarly high technical success rate with comparable safety compared with those performed by highly experienced specialists in contemporary Japanese context.

Outcomes of chronic total occlusion percutaneous coronary intervention in patients with prior coronary artery bypass graft surgery: Insights from the LATAM CTO registry

OBJECTIVES

To evaluate the outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) in patients with and without prior coronary artery bypass graft (CABG) surgery.

BACKGROUND

Data on the outcomes of CTO PCI in patients with versus without CABG remains limited and with scarce representation from developing regions like Latin America.

METHODS

We evaluated patients undergoing CTO PCI in 42 centers participating in the LATAM CTO registry between 2008 and 2020. Statistical analyses were stratified according to CABG status. The outcomes of interest were technical and procedural success and in-hospital major adverse cardiac and cerebrovascular events (MACCE).

RESULTS

A total of 1662 patients were included (n = 1411 [84.9%] no-CABG and n = 251 [15.1%] prior-CABG). Compared with no-CABG, those with prior-CABG were older (67 ± 11 vs. 64 ± 11 years; p < 0.001), had more comorbidities and lower left ventricular ejection fraction (52.8 ± 12.8% vs. 54.4 ± 11.7%; p = 0.042). Anatomic complexity was higher in the prior-CABG group (J-CTO score 2.46 ± 1.19 vs. 2.10 ± 1.22; p < 0.001; PROGRESS CTO score 1.28 ± 0.89 vs. 0.91 ± 0.85; p < 0.001). Absence of CABG was associated with lower risk of technical and procedural failure (OR: 0.60, 95% CI: 0.43-0.85 and OR: 0.58, 95% CI: 0.40-0.83, respectively). No significant differences in the incidence of in-hospital MACCE (3.8% no-CABG vs. 4.4% prior-CABG; p = 0.766) were observed between groups.

CONCLUSION

In a contemporary multicenter CTO-PCI registry from Latin America, prior-CABG patients had more comorbidities, higher anatomical complexity, lower success, and similar in-hospital adverse event rates compared with no-CABG patients.

Chronic total occlusion revascularization: A complex piece to "complete" the puzzle

Treatment of coronary chronic total occlusion (CTO) with percutaneous coronary intervention (PCI) has rapidly increased during the past decades. Different strategies and approach were developed in the recent past years leading to an increase in CTO-PCI procedural success. The goal to achieve an extended revascularization with a high rate of completeness is now supported by strong scientific evidences and consequently, has led to an exponential increase in the number of CTO-PCI procedures, even if are still underutilized. It has been widely demonstrated that complete coronary revascularization, achieved by either coronary artery bypass graft or PCI, is associated with prognostic improvement, in terms of increased survival and reduction of major adverse cardiovascular events. The application of “contemporary” strategies aimed to obtain a state-of-the-art revascularization by PCI allows to achieve long-term clinical benefit, even in high-risk patients or complex coronary anatomy with CTO. The increasing success of CTO-PCI, allowing a complete or reasonable incomplete coronary revascularization, is enabling to overcome the last great challenge of interventional cardiology, adding a “complex” piece to “complete” the puzzle.

Contemporary Issues in Chronic Total Occlusion Percutaneous Coronary Intervention

Remarkable progress has been achieved in chronic total occlusion (CTO) percutaneous coronary intervention (PCI) in recent years, with refinement of the indications and technical aspects of the procedure, imaging, and complication management. Randomized controlled trials and rigorous prospective registries have provided high-quality data on the benefits and risks of CTO PCI. Global collaboration has led to an agreement on nomenclature, indications, endpoint definition, and principles of clinical trial design that have been distilled in global consensus documents such as the CTO Academic Research Consortium. Increased use of preprocedural coronary computed tomography angiography and intraprocedural intravascular imaging, as well as development of novel techniques and structured CTO crossing and complication management algorithms, allow a systematic, stepwise approach to this difficult lesion subset. This state-of-the-art review provides a comprehensive discussion about the most recent developments in the indications, preprocedural planning, technical aspects, complication management, and future directions of CTO PCI.

CTO in Contemporary PCI

Percutaneous Coronary Intervention (PCI) of Chronic Total Occlusions (CTO) represents the most challenging procedure in modern endovascular treatments. In recent years, the success rate of CTO PCI has substantially improved, owing to increasing operator expertise and advancements in CTO equipment and algorithms as well as the development of expert consensus documents. In this review, we summarize existing evidence for CTO PCI, its success/ risk prediction scoring tools, procedural principles and complications and provide an insight into the future role of CTO PCI.

The evolution of the CTO-PCI landscape in Belgium and Luxembourg: a four-year appraisal

BACKGROUND

To chart the evolution of the CTO-PCI landscape in Belgium and Luxembourg, the Belgian Working Group on Chronic Total Occlusions (BWGCTO) was established in 2016.

METHODS

Between May 2016 and December 2019, patients undergoing a CTO-PCI treatment were prospectively and consecutively enrolled. Twenty-one centres in Belgium and one in Luxembourg participated. Individual operators had mixed levels of expertise in treating CTO lesions. Demographic, angiographic, procedural parameters and incidence of major adverse cardiac and cerebrovascular events (MACCE) were systematically registered.

RESULTS

Over a four-year enrolment period, 1832 procedures were performed in 1733 patients achieving technical success in 1474 cases (80%), with an in-hospital MACCE rate of 2.3%. Fifty-nine (3%) cases were re-attempt procedures of which 41 (69%) were successful. High-volume centres treated more complex lesions (mean J-CTO score: 2.15 ± 1.21) as compared to intermediate (mean J-CTO score: 1.72 ± 1.23; p < 0.001) and low-volume centres (mean J-CTO score: 0.99 ± 1.21; p = 0.002). Despite this, success rates did not differ between centres (p = 0.461). Overall success rates did not differ over time (p = 0.810). High-volume centres progressively tackled more complex CTOs while keeping success rates stable. In all centres, the most applied strategy was antegrade wire escalation (83%). High-volume centres more often successfully applied antegrade dissection and re-entry and retrograde techniques in lesions with higher complexity.

CONCLUSION

With variable experience levels, operators treated CTOs with high success and relatively few complications. Although AWE remains the most used technique, it is paramount for operators to be skilled in all contemporary techniques in order to be successful in more complex CTOs.

In-hospital outcomes of patients with chronic kidney disease undergoing percutaneous coronary intervention for chronic total occlusion: a systematic review and meta-analysis

BACKGROUND

The relative safety and efficacy of percutaneous coronary intervention (PCI) for chronic total occlusions (CTO) in patients with chronic kidney disease (CKD) have not been well defined. We performed a systematic review and meta-analysis of observational studies to assess in-hospital outcomes in this population.

METHODS

We searched MEDLINE, EMBASE, and Cochrane Library databases from inception to April 2020 for all clinical trials and observational studies. Five observational studies with a total of 6769 patients met our inclusion criteria. Patients were divided into two groups based on estimated glomerular filtration rate (eGFR <60 ml/min/1.73m2 in CKD group and ≥ 60 ml/min/1.73m2 in non-CKD group). The primary outcome was in-hospital mortality. Secondary outcomes were acute kidney injury, coronary injury (perforation, dissection or tamponade), stroke and procedural success. Mantel-Haenszel random-effects model was used to calculate the odds ratio (OR) and 95% confidence intervals (CI).

RESULTS

In-hospital mortality was significantly higher among patients with CKD undergoing PCI for CTO (OR: 5.16, 95% CI: 2.60-10.26, P < 0.00001). Acute kidney injury (OR: 2.54, 95% CI: 1.89-3.40, P < 0.00001) and major bleeding (OR: 2.58, 95% CI: 1.20-5.54, P < 0.01) were also more common in the CKD group. No significant difference was observed in the occurrence of stroke (OR: 2.36, 95% CI: 0.74-7.54, P < 0.15) or coronary injury (OR: 1.38, 95% CI: 0.98-1.93, P < 0.06) between the two groups. Non-CKD patients had a higher likelihood of procedural success compared to CKD patients (OR: 0.66, 95% CI: 0.57-0.77, P < 0.00001).

CONCLUSION

Patients with CKD undergoing PCI for CTO have a significantly higher risk of in-hospital mortality, acute kidney injury and major bleeding when compared to non-CKD patients. They also have a lower procedural success rate.

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.

Outcomes of contemporary versus conventional reverse controlled and antegrade and retrograde subintimal tracking in chronic total occlusion revascularization

BACKGROUND

Chronic total occlusion (CTO) lesions remain technically challenging for percutaneous coronary intervention (PCI). The introduction of a retrograde approach has allowed marked improvement in the success rate of CTO recanalization. Reverse controlled anterograde and retrograde sub-intimal tracking (reverse CART) is the predominant retrograde wire crossing technique and can be broadly classified into three categories: (1) conventional (2) contemporary and (3) extended. The present study aimed to compare the safety and efficacy of conventional and contemporary reverse CART techniques.

METHODS

From March 2015 to May 2020, 303 patients achieving successful retrograde guidewire crossing with conventional or contemporary reverse CART during CTO PCI were included in the study. The patient characteristics, procedural outcomes and in-hospital and 1-year clinical events were compared between the conventional and contemporary groups.

RESULTS

The distributions of the baseline and angiographic characteristics were similar in both study arms, except the CTO lesions of the conventional group were more complex, as reflected by borderline significantly higher mean J-CTO scores (3.4 ± 0.7 vs. 3.3 ± 0.8; p = 0.059). Recanalization using contemporary reverse CART was associated with a short procedure time (189.8 ± 44.4 vs. 181.7 ± 37.3 min; p = 0.044) and decreased procedural complications, particularly target vessel perforation (3.6% vs. 0.6%; p = 0.063) and major side-branch occlusion (36.7% vs. 28.0%; p = 0.051). Technical and procedural success and the in-hospital and 1-year outcomes were not significantly different between the groups.

CONCLUSIONS

Contemporary reverse CART is associated with favorably high efficiency and low-complication rates and carries a comparable success rate and 1-year clinical outcomes as conventional reverse CART.

Viability and functional recovery after chronic total occlusion percutaneous coronary intervention

OBJECTIVES

This study evaluated myocardial viability as well as global and regional functional recovery after successful chronic coronary total occlusion (CTO) percutaneous coronary intervention (PCI) using sequential quantitative cardiac magnetic resonance (CMR) imaging.

BACKGROUND

The patient benefits of CTO PCI are being questioned.

METHODS

In a single high-volume CTO PCI center patients were prospectively scheduled for CMR at baseline and 3 months after successful CTO PCI between 2013 and 2018. Segmental wall thickening (SWT) and percentage late gadolinium enhancement (LGE) were quantitatively measured per segment. Viability was defined as dysfunctional myocardium (<2.84 mm SWT) with no or limited scar (≤50% LGE).

RESULTS

A total of 132 patients were included. Improvement of left ventricular ejection fraction was modest after CTO PCI (from 48.1 ± 11.8 to 49.5 ± 12.1%, p < 0.01). CTO segments with viability (N = 216, [31%]) demonstrated a significantly higher increase in SWT (0.80 ± 1.39 mm) compared to CTO segments with pre-procedural preserved function (N = 456 [65%], 0.07 ± 1.43 mm, p < 0.01) or extensive scar (LGE >50%, N = 26 [4%], -0.08 ± 1.09 mm, p < 0.01). Patients with ≥2 CTO segments viability showed more SWT increase in the CTO territory compared to patients with 0-1 segment viability (0.49 ± 0.93 vs. 0.12 ± 0.98 mm, p = 0.03).

CONCLUSIONS

Detection of dysfunctional myocardial segments without extensive scar (≤50% LGE) as a marker for viability on CMR aids in identifying patients with significant regional functional recovery after CTO PCI.

The importance of side branch preservation in the treatment of chronic total occlusions with bifurcation lesions

OBJECTIVES

The aim of this study was to identify the predictive factors for suboptimal result in side branch (SB) in chronic total occlusion (CTO) bifurcation lesions and clinical outcomes of patients with suboptimal result in SB.

BACKGROUND

There is little evidence on the optimal strategy for bifurcation lesions in CTO.

METHODS

We retrospectively reviewed 314 consecutive bifurcation lesions in CTO with SB ≥ 2.5 mm in 3 hospitals from March 2010 to June 2018. Patients were divided into the two groups based on the suboptimal SB treatment (SST) and optimal SB treatment (OST) groups. The baseline characteristics, procedural and clinical outcomes were compared between the two groups. This study also evaluated the predictors of suboptimal result in SB.

RESULTS

Suboptimal result in SB occurred in 47 cases. Presence of stenosis in SB, bifurcations located within the occluded segment and sub-intimal tracking at SB ostium was an independent predictor of suboptimal result in SB. The cumulative incidence of target lesion revascularization (TLR) in all lesions was not significantly different between the two groups, however, TLR in right coronary artery (RCA) was significantly higher in the SST group. In the Cox regression analysis, suboptimal result in SB in RCA and sub-intimal tracking were independent predictors of TLR for MB. In patients with bifurcations located within the occluded segment, usage of two-stent technique was significantly lower in the SST group.

CONCLUSIONS

Meticulous procedures are required for SB preservation to improve not only SB prognosis but also MB, especially in RCA.

Clinical and angiographic outcomes of crossing techniques for coronary chronic total occlusions: the ISAR-CTO registry

BACKGROUND

Clinical and angiographic outcomes following recanalisation of coronary chronic total occlusions (CTO) through contemporary dissection and re-entry techniques (DART) as opposed to intraplaque techniques remain controversial.

AIMS

The aim of this study was to compare clinical and angiographic outcomes following subintimal and intraplaque CTO recanalisation.

METHODS

A total of 454 consecutive patients undergoing successful CTO recanalisation (473 vessels) were included. Intraplaque techniques were used in 403 (85.2%) and DART in 70 (14.8%) vessels. Surveillance angiography was scheduled at 6-9 months and clinical follow-up was performed up to 12 months.

RESULTS

There were no significant differences in terms of the cumulative incidence of MACE (p=0.908) or binary restenosis (p=0.320) between the two groups. There was no independent correlation between recanalisation technique and MACE occurrence or in-segment binary restenosis. Target lesion revascularisation (TLR) was performed in 60 (17.5%) and 12 (18.1%) (p=0.719) lesions, respectively. The occurrence of occlusive restenosis was low (7 [2.3%] vs 1 [1.6%]; p=0.824) and comparable between groups.

CONCLUSIONS

Contemporary DART are associated with similar midterm clinical and angiographic outcomes compared to intraplaque recanalisation. The rate of occlusive restenosis was low and comparable in both groups. Regardless of recanalisation technique, the overall incidences of binary restenosis and TLR following CTO recanalisation remain higher than those reported for non-CTO PCI.

Outcomes of retrograde approach for chronic total occlusions by guidewire location

BACKGROUND

Connecting the antegrade wire (AW) and the retrograde wire (RW) is a goal of chronic total occlusion (CTO) treatment, but angiographic guidewire location is sometimes misleading.

AIMS

The aim of this study was to evaluate the association between intravascular ultrasound (IVUS)-defined AW and RW position and procedural outcomes when treating CTO lesions using the retrograde approach.

METHODS

Overall, 191 CTO lesions treated using an IVUS-guided retrograde approach at three centres in Japan, China, and the USA were included.

RESULTS

When the AW and RW angiographically overlapped, four wire positions were seen on IVUS: (i) AW within the plaque (AW-intraplaque) and RW-intraplaque in 34%; (ii) AW-intraplaque and RW in the subintimal space (RW-subintima) in 28%; (iii) AW-subintima and RW-subintima in 22%; or (iv) AW-subintima and RW-intraplaque in 16%. The procedure succeeded without repositioning the wire in 89% of AW-intraplaque/RW-intraplaque, 61% of AW-intraplaque/RW-subintima and 57% of AW-subintima/RW-subintima, but only one (3%) AW-subintima/RW-intraplaque. Lesion and procedure complexity and failure/complications were greatest in AW-subintima/RW-intraplaque.

CONCLUSIONS

IVUS-identified vascular compartment concordance versus IVUS-identified vascular compartment mismatch leads to higher success rates irrespective of intraplaque or subintimal passage. AW-subintima/RW-intraplaque was associated with the most complex CTO morphology and procedure, and repositioning the wire was almost always necessary. Visual summary. When the antegrade wire is in the subintimal space and the retrograde wire is in the intraplaque, re-wiring is almost always necessary.

Safety and efficacy of dedicated guidewire, microcatheter, and guide catheter extension technologies for chronic total coronary occlusion revascularization: Primary results of the Teleflex Chronic Total Occlusion Study

BACKGROUND

Description of procedural outcomes using contemporary techniques that apply specialized coronary guidewires, microcatheters, and guide catheter extensions designed for chronic total occlusion (CTO) percutaneous revascularization is limited.

METHODS

A prospective, multicenter, single-arm study was conducted to evaluate procedural and in-hospital outcomes among 150 patients undergoing attempted CTO revascularization utilizing specialized guidewires, microcatheters and guide extensions. The primary endpoint was defined as successful guidewire recanalization and absence of in-hospital cardiac death, myocardial infarction (MI), or repeat target lesion revascularization (major adverse cardiac events, MACE).

RESULTS

The prevalence of diabetes was 32.7%; prior MI, 48.0%; and previous bypass surgery, 32.7%. Average (mean ± standard deviation) CTO length was 46.9 ± 20.5 mm, and mean J-CTO score was 1.9 ± 0.9. Combined radial and femoral arterial access was performed in 50.0% of cases. Device utilization included: support microcatheter, 100%; guide catheter extension, 64.0%; and mean number of study guidewires/procedure was 4.8 ± 2.6. Overall, procedural success was achieved in 75.3% of patients. The rate of successful guidewire recanalization was 94.7%, and in-hospital MACE was 19.3%. Achievement of TIMI grade 2 or 3 flow was observed in 93.3% of patients. Crossing strategies included antegrade (54.0%), retrograde (1.3%) and combined antegrade/retrograde techniques (44.7%). Clinically significant perforation resulting in hemodynamic instability and/or requiring intervention occurred in 16 (10.7%) patients.

CONCLUSIONS

In a multicenter, prospective registration study, favorable procedural success was achieved despite high lesion complexity using antegrade and retrograde guidewire maneuvers and with acceptable safety, yet with comparably higher risk than conventional non-CTO PCI.

Global Chronic Total Occlusion Crossing Algorithm: JACC State-of-the-Art Review

The authors developed a global chronic total occlusion crossing algorithm following 10 steps: 1) dual angiography; 2) careful angiographic review focusing on proximal cap morphology, occlusion segment, distal vessel quality, and collateral circulation; 3) approaching proximal cap ambiguity using intravascular ultrasound, retrograde, and move-the-cap techniques; 4) approaching poor distal vessel quality using the retrograde approach and bifurcation at the distal cap by use of a dual-lumen catheter and intravascular ultrasound; 5) feasibility of retrograde crossing through grafts and septal and epicardial collateral vessels; 6) antegrade wiring strategies; 7) retrograde approach; 8) changing strategy when failing to achieve progress; 9) considering performing an investment procedure if crossing attempts fail; and 10) stopping when reaching high radiation or contrast dose or in case of long procedural time, occurrence of a serious complication, operator and patient fatigue, or lack of expertise or equipment. This algorithm can improve outcomes and expand discussion, research, and collaboration.

[Technical armamentarium for chronic total occlusion of coronary vessels]

Percutaneous revascularization of chronic total occlusion (CTO) of coronary vessels represents a major challenge for contemporary interventional cardiologists. In the last decade there has been an unprecedented effort towards the standardization of revascularization procedures for CTO of coronary vessels. This endeavour has been possible by virtue of the growing interest of various cardiological societies for this patient group. Along with supportive endovascular technologies and percutaneous devices specifically dedicated to this interventional target, the increasing experience of interventionalists enabled continuously growing success for revascularization of CTO of coronary vessels. This review article highlights the currently available tools as well as technologies, techniques and strategies for the percutaneous recanalization of CTO of coronary vessels.

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.

Chronic total occlusion techniques in non-chronic total occlusion cases, the wealth of a large toolbox

The development of dedicated expertise in chronic total occlusion (CTO) percutaneous coronary interventions (PCI) techniques is a time-consuming process that makes the CTO-operator more versatile and resolute in routine PCI. We describe three characteristic cases where the use of a specific CTO-technique was applied in the setting of complicated PCI to prevent a "nightmare" in the catheterisation laboratory. More specifically, management of occlusive dissections was successfully mastered with a retrograde technique in the first case, with a sub-intimal transcatheter withdrawal technique in the second one and with an antegrade dissection-re-entry technique in the last patient. In all the described cases, the adoption of these advanced techniques would have been substantially unfeasible for non-CTO operators or without a CTO-operator guidance. Fellows undergoing training in invasive cardiology should be encouraged to enrol in a CTO programme for at least part of their fellowship in order to become acquainted to these CTO techniques.

A new combined antegrade and retrograde approach for chronic total occlusion recanalization: Facilitated antegrade fenestration and re-entry

While antegrade techniques remain the cornerstone of chronic total occlusion (CTO) percutaneous coronary intervention (PCI), operators have often to resort to the retrograde approach in complex occlusions. In particular, lesions with proximal cap ambiguity, unclear vessel course and/or poor distal landing zone are difficult to tackle with either antegrade wiring or antegrade dissection and re-entry (ADR), and often require the retrograde approach. After collateral channel crossing, the retrograde approach usually culminates with either reverse controlled antegrade and retrograde subintimal tracking (CART) or retrograde true lumen crossing. Both techniques usually involve the use of an externalization wire, which requires keeping a higher activate clotting time to prevent thrombosis of the retrograde channel and is potentially associated with risk for donor vessel injury. In 2018, we described antegrade fenestration and re-entry (AFR), a targeted ADR technique in which fenestrations between the false and true lumen are created by antegrade balloon dilatation in the extraplaque space at the level of the distal cap, which are subsequently engaged by a polymer-jacketed wire to achieve re-entry. We hypothesized that AFR can also expedite antegrade crossing of the CTO after a wire has reached the distal vessel in a retrograde fashion. In this report, we present two cases in which we successfully achieved antegrade CTO crossing with AFR following retrograde advancement of a guidewire to the distal cap, in new variant of the technique, which we called "facilitated AFR".

Ischemic Burden Reduction and Long-Term Clinical Outcomes After Chronic Total Occlusion Percutaneous Coronary Intervention

OBJECTIVES

The authors sought to evaluate the impact of ischemic burden reduction after chronic total occlusion (CTO) percutaneous coronary intervention (PCI) on long-term prognosis and cardiac symptom relief.

BACKGROUND

The clinical benefit of CTO PCI is questioned.

METHODS

In a high-volume CTO PCI center, 212 patients prospectively underwent quantitative [¹⁵O]H₂O positron emission tomography perfusion imaging before and three months after successful CTO PCI between 2013-2019. Perfusion defects (PD) (in segments) and hyperemic myocardial blood flow (hMBF) (in ml · min^-1 · g^-1) allocated to CTO areas were related to prognostic outcomes using unadjusted (Kaplan-Meier curves, log-rank test) and risk-adjusted (multivariable Cox regression) analyses. The prognostic endpoint was a composite of all-cause death and nonfatal myocardial infarction.

RESULTS

After a median [interquartile range] of 2.8 years [1.8 to 4.3 years], event-free survival was superior in patients with ≥3 versus <3 segment PD reduction (p < 0.01; risk-adjusted p = 0.04; hazard ratio [HR]: 0.34 [95% confidence interval (CI): 0.13 to 0.93]) and with hMBF increase above (Δ≥1.11 ml · min^-1 · g^-1) versus below the population median (p < 0.01; risk-adjusted p < 0.01; HR: 0.16 [95% CI: 0.05 to 0.54]) after CTO PCI. Furthermore, event-free survival was superior in patients without versus any residual PD (p < 0.01; risk-adjusted p = 0.02; HR: 0.22 [95% CI: 0.06 to 0.76]) or with a residual hMBF level >2.3 versus ≤2.3 ml · min^-1 · g^-1 (p < 0.01; risk-adjusted p = 0.03; HR: 0.25 [95% CI: 0.07 to 0.91]) at follow-up positron emission tomography. Patients with residual hMBF >2.3 ml · min^-1 · g^-1 were more frequently free of angina and dyspnea on exertion at long-term follow-up (p = 0.04).

CONCLUSIONS

Patients with extensive ischemic burden reduction and no residual ischemia after CTO PCI had lower rates of all-cause death and nonfatal myocardial infarction. Long-term cardiac symptom relief was associated with normalization of hMBF levels after CTO PCI.

Retrograde chronic total occlusion percutaneous coronary intervention using single catheter: A single centre registry

OBJECTIVES

To analyse the feasibility, safety and procedural outcomes of percutaneous coronary intervention (PCI) for chronic total occlusions (CTO) through retrograde approach using single catheter.

METHODS

Our study was a retrospective observational study that enrolled patients who underwent retrograde CTO PCI using a single catheter between June 2016 and February 2020. Clinical success was defined as successful completion of CTO PCI without associated in-hospital major clinical complications like death, myocardial infarction, stroke or urgent revascularisation. Technical success was defined as successful completion of CTO PCI using single catheter and minimum diameter stenosis of <30% with thrombolysis in myocardial infarction (TIMI) flow grade 3, without significant side branch occlusion, flow-limiting dissection, distal embolization, or angiographic thrombus.

RESULTS

Totally 102 patients underwent retrograde CTO PCI during the study period. Out of which, 15 cases were attempted using single catheter. Mean age of the population was 59.1 ± 8.9 years (males: 86.7%) and the left ventricular ejection fraction (LVEF) was (61% ± 9.1%). Mean number of diseased arteries was 2.1 ± 0.7, length of the CTO was 25.5 ± 7.4 mm and J-CTO score was 2.3 ± 0.7. We achieved a technical success rate of 73.3% using single catheter, and the overall clinical success (Including single catheter and ping pong) was obtained in 86.7% cases. One patient (6.7%) developed cardiac tamponade and none of study population required dialysis for contrast induced acute kidney injury (CI-AKI) CONCLUSIONS: Retrograde CTO PCI using single catheter is a technically challenging procedure when compared with other CTO PCI. Our study demonstrated acceptable outcomes which is comparable to other antegrade and retrograde CTO PCI registries.

Predictors of prolonged guidewire manipulation time for native coronary chronic total occlusion percutaneous coronary intervention via primary antegrade approach

OBJECTIVES

This study aimed to identify the predictive factors for the guidewire manipulation time (GWMT) of ≥20 and 30 min for chronic total occlusion-percutaneous coronary intervention (CTO-PCI) via the primary antegrade approach (PAA).

BACKGROUND

Selection of primary retrograde approach (PRA) and the optimal timing to switch from antegrade to retrograde approach for coronary CTO-PCI is still debatable.

METHODS

Using the Japanese CTO-PCI expert registry data, we selected and analyzed 4461 patients who underwent CTO-PCI via PAA alone. The considerable lesion/anatomical factors for GWMT ≥20 and 30 min were analyzed. The risks of prolonged GWMT ≥20 and 30 min were stratified as easy, intermediate, difficult, and very difficult according to the multivariate analysis.

RESULTS

Nine lesion/anatomical characteristics (blunt stump, side branch at proximal cap, bifurcation at the exit point, calcification, tortuosity, occlusion length ≥ 20 mm, reattempt, nonleft anterior descending artery (nonleft anterior descending artery [LAD]), and tandem CTO) were independent predictors of GWMT ≥20 min (all p < 0.05). Excluding the nonLAD and tandem CTO, the same factors of GWMT ≥20 min correlated with GWMT ≥30 min (all p < 0.05). The distributions were increased in easy, intermediate, difficult, and very difficult subsets of GWMT ≥20 min (58.3%, 77.2%, 89.1%, and 100%) and GWMT ≥30 min (47.5%, 69.2%, 83.9%, and 100%).

CONCLUSIONS

These predictive factors of prolonged GWMT should be assessed before CTO-PCI via PAA and when considering an adequate timing to switch the retrograde or PRA if clinically available.

A Practical Approach to Hybrid Coronary Revascularization

Combined surgical and percutaneous coronary revascularization, ie, hybrid coronary revascularization (HCR) consists of surgical left internal mammary artery (LIMA) bypass to the left anterior descending artery (LAD) and percutaneous revascularization of other diseased coronary arteries. Developed as a 1-stage procedure, HCR has not been widely adopted by the cardiovascular community. The recommended minimally invasive approach through a small left thoracotomy incision is technically demanding, and same-day percutaneous revascularization requires a hybrid operating room that is not available in most hospitals. In this review, we consider present HCR protocols, barriers to widespread adoption of HCR, and we give special attention to the surgical approach for the LIMA graft to the LAD and the timing of percutaneous revascularization. We conclude that grafting the LIMA to the LAD through a median sternotomy approach and delaying the percutaneous revascularization may facilitate the widespread use of HCR in patients with multivessel coronary artery disease and a low to intermediate Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery score.

Intravascular Lithotripsy for Calcium Modification in Chronic Total Occlusion Percutaneous Coronary Intervention

Intravascular lithotripsy (IVL) has been shown to be safe and effective for calcium modification in nonocclusive coronary artery disease (CAD), but there are only case reports of its use in calcified chronic total occlusions (CTO). We report data from an international multicenter registry of IVL use during CTO percutaneous coronary intervention (PCI) and provide provisional data regarding its efficacy and safety. During the study period, IVL was used in 55 of 1053 (5.2%) CTO PCI procedures. IVL was used within the occluded segment after successful CTO crossing in 53 procedures and during incomplete CTO crossing in 2 cases. The mean J-CTO score was 3.1. CTO PCI technical and procedural success was achieved in 53 (96%) and 51 (93%) cases. Six patients had a procedural complication, with 3 main vessel perforations (5%). Two had covered stent implantation, one required pericardiocentesis, and one was managed conservatively. All had combination therapy with another calcium modification device. Two patients had a procedural myocardial infarction (PMI) (4%), and two others had a major adverse cardiovascular event (MACE) (4%) at a median follow-up of 13 (4–21) months. IVL can effectively facilitate calcium modification during CTO PCI. More data are required to establish the efficacy and safety of IVL and other calcium modification devices when used extraplaque or in combination during CTO PCI.

Effect of Coronary CTA on Chronic Total Occlusion Percutaneous Coronary Intervention: A Randomized Trial

OBJECTIVES

The purpose of this study was to test whether the success rate of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) increased with pre-procedural coronary computed tomography angiography (CTA).

BACKGROUND

Coronary CTA provides valuable information before and during CTO-PCI. However, there are no randomized data that explore whether coronary CTA increases its success rate.

METHODS

In this multicenter, randomized trial, a total of 400 patients with CTO were randomized to receive PCI with pre-procedural coronary CTA (coronary CTA-guided group; n = 200) or without coronary CTA (angiography-guided group; n = 200) between January 2014 and September 2019. The primary endpoint was the successful recanalization rate, a final TIMI (Thrombolysis In Myocardial Infarction) grade ≥2, and ≤30% residual stenosis on the final angiogram.

RESULTS

A total of 10 operators performed PCI. Successful recanalization was achieved in 187 patients (93.5%) in the coronary CTA-guided group and in 168 patients (84.0%) in the angiography-guided group (absolute difference, 9.5% [95% confidence interval: 3.4% to 15.6%]; p = 0.003). When comparing the success rates according to the Multicenter CTO Registry of Japan score (J-CTO), the coronary CTA guidance was favored over the angiography-guidance in the subset of J-CTO ≥2 versus in the subset of J-CTO <2 (p interaction = 0.035). Coronary perforations occurred in 2 (1%) and 8 patients (4%) in the coronary CTA- and angiography-guided groups, respectively (p = 0.055). Periprocedural myocardial infarction was not observed in the coronary CTA-guided group, whereas it occurred in 4 patients (2%) in the angiography-guided group (p = 0.123). Total procedure and fluoroscopic times were not different. There were no differences between the groups in the occurrences of cardiac death, target vessel-related myocardial infarction, or target-vessel revascularization at 1 year.

CONCLUSIONS

Pre-procedural coronary CTA-guidance for CTO resulted in higher success rates with numerically fewer immediate periprocedural complications such as coronary perforations or periprocedural myocardial infarction than angiography guidance. Higher success rates were more prominently observed in patients with CTO who had a high J-CTO score than those who did not. (Role of CT Scan for the Successful Recanalization of Chronic Total Occlusion; a Randomized Comparison Between 3D CT-guided PCI vs. Conventional Treatment [CT-CTO Trial]; NCT02037698).

A Clinical Analysis of the Treatment of Chronic Coronary Artery Occlusion With Antegrade Dissection Reentry

Objective: This study aimed to investigate the efficacy and safety of antegrade dissection re-entry (ADR) technique in the percutaneous coronary intervention (PCI) to open chronic total occlusion (CTO) lesions. Methods: The baseline, angiographic results, PCI success rate, and major adverse cardiac events (MACE) during the 12 months of follow-up were compared between 48 patients who did not use ADR in the treatment of CTO lesions (control group) and 50 patients who used ADR (treatment group). Results: The control group comprised 48 patients who had 52 CTO lesions, and the treatment group comprised 50 patients who had 58 CTO lesions. The success rate of PCI in the treatment group (89.7 vs. 71.2%, P = 0.047) was significantly higher than in the control group, where six patients had in-stent restenosis (ISR, ISR-CTO) that were all recanalized. The mean PCI time (71 ± 25 min vs. 95 ± 33 min, P = 0.041), X-ray exposure time (42 ± 17 min vs. 71 ± 22 min, P = 0.032), contrast agent dosage (98 ± 26 ml vs. 178 ± 63 ml, P = 0.029), MACE incidence during the 12 months of follow-up (22.0 vs. 41.7%, P = 0.046) and recurrent myocardial infarction incidence (10.0 vs. 27.1%, P = 0.047) were significantly lower in the treatment group than in the control group. The differences were all statistically significant. Conclusion: It is safe and effective to use the ADR technique in PCI for coronary artery CTO lesions. The technique shortens the operation time, reduces the radiation dose of doctors and patients and the use dose of contrast agents, and improves patients' prognoses.

Randomized Comparison Between Radial and Femoral Large-Bore Access for Complex Percutaneous Coronary Intervention

OBJECTIVES

The aim of this study was to investigate whether transradial (TR) percutaneous coronary intervention (PCI) is superior to transfemoral (TF) PCI in complex coronary lesions with large-bore guiding catheters with respect to clinically relevant access site-related bleeding or vascular complications.

BACKGROUND

The femoral artery is currently the most applied access site for PCI of complex coronary lesions, especially when large-bore guiding catheters are required. With downsizing of TR equipment, TR PCI may be increasingly applied in these patients and might be a safer alternative compared with the TF approach.

METHODS

An international prospective multicenter trial was conducted, randomizing 388 patients with planned PCI for complex coronary lesions, including chronic total occlusion, left main, heavy calcification, or complex bifurcation, to either 7-F TR access (TRA) or 7-F TF access (TFA). The primary endpoint was defined as access site-related clinically significant bleeding or vascular complications requiring intervention at discharge. The secondary endpoint was procedural success.

RESULTS

The primary endpoint event rate was 3.6% for TRA and 19.1% for TFA (p < 0.001). The crossover rate from radial to femoral access was 3.6% and from femoral to radial access was 2.6% (p = 0.558). The procedural success rate was 89.2% for TFA and 86.0% for TRA (p = 0.285). There was no difference between TFA and TRA with regard to procedural duration, contrast volume, or radiation dose.

CONCLUSIONS

In patients undergoing PCI of complex coronary lesions with large-bore access, radial compared with femoral access is associated with a significant reduction in clinically relevant access-site bleeding or vascular complications, without affecting procedural success. (Complex Large-Bore Radial Percutaneous Coronary Intervention [PCI] Trial [Color]; NCT03846752).

Outcomes of retrograde chronic total occlusion percutaneous coronary intervention: A report from the OPEN-CTO registry

OBJECTIVES

We sought to assess in-hospital and long-term outcomes of retrograde compared with antegrade-only percutaneous coronary intervention for chronic total occlusion (CTO PCI).

BACKGROUND

Procedural and clinical outcomes following retrograde compared with antegrade-only CTO PCI remain unknown.

METHODS

Using the core-lab adjudicated OPEN-CTO registry, we compared the outcomes of retrograde to antegrade-only CTO PCI. Primary endpoints included were in-hospital major adverse cardiac and cerebrovascular events (MACCE) (all-cause death, stroke, myocardial infarction [MI], emergency cardiac surgery, or clinically significant perforation) and MACCE at 1-year (all-cause death, MI, stroke, target lesion revascularization, or target vessel reocclusion).

RESULTS

Among 885 single CTO procedures from the OPEN-CTO registry, 454 were retrograde and 431 were antegrade-only. Lesion complexity was higher (J-CTO score: 2.7 vs. 1.9; p < .001) and technical success lower (82.4 vs. 94.2%; p < .001) in retrograde compared with antegrade-only procedures. All-cause death was higher in the retrograde group in-hospital (2 vs. 0%; p = .003), but not at 1-year (4.9 vs. 3.3%; p = .29). Compared with antegrade-only procedures, in-hospital MACCE rates (composite of all-cause death, stroke, MI, emergency cardiac surgery, and clinically significant perforation) were higher in the retrograde group (10.8 vs. 3.3%; p < .001) and at 1-year (19.5 vs. 13.9%; p = .03). In sensitivity analyses landmarked at discharge, there was no difference in MACCE rates at 1 year following retrograde versus antegrade-only CTO PCI. Improvements in Seattle Angina Questionnaire Quality of Life scores at 1-year were similar between the retrograde and antegrade-only groups (29.9 vs 30.4; p = .58).

CONCLUSIONS

In the OPEN-CTO registry, retrograde CTO procedures were associated with higher rates of in-hospital MACCE compared with antegrade-only; however, post-discharge outcomes, including quality of life improvements, were similar between technical modalities.

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.

Real world perspective of coronary chronic total occlusion in third world countries: A tertiary care centre study from northern India

OBJECTIVES

The aim of this study is to determine the prevalence, clinical characteristics, angiographic profile and predictors of outcome for percutaneous coronary interventions (PCI) of coronary chronic total occlusions (CTO) in a tertiary referral centre of north India.

BACKGROUND

There is no data on the prevalence and very few reports on clinical characteristics, angiographic profile and outcome of PCI in CTO from India.

METHODS

Retrospective analysis was done for the data of 12,020 patients undergoing coronary angiography (CAG) between January 2018 to January 2019 at our centre. Detailed baseline clinical, angiographic and revascularization data was collected. Outcome of CTO PCI was also noted. All baseline parameters were analysed for predicting the outcome of CTO PCI.

RESULTS

CTO was identified in 16.3% (1968) patients undergoing CAG and in 24.4% of patients with hemodynamically significant CAD. CTO was predominantly found in LAD (48%) followed by RCA (42.9%) and LCx (25.3%) arterial distribution. Mean JCTO score was 1.93 ± 0.7. PCI as a management strategy was adopted in 456 of 1968 patients (23.1%) and was successful in 340 of 456 (74.6%) of patients. Almost all CTO PCI were attempted by an antegrade approach only. Increasing age, male sex, CTO in LCx arterial distribution and higher J CTO score were associated with poorer outcome in CTO PCI.

CONCLUSIONS

CTO's are commonly encountered during CAG procedures. In patients undergoing CTO PCI, a fair success rate can be achieved in a high volume experienced centre.

A contemporary review of clinical significances of percutaneous coronary intervention for chronic total occlusions, with some Japanese insights

The clinical "significance" of percutaneous coronary intervention for coronary chronic total occlusion (CTO-PCI) has been evaluated. In the beginning, the effects on clinical endpoints were investigated by comparisons between cases of success and failure of CTO-PCI, which mostly demonstrated better long-term outcomes in the successful cases. Similarly, improvement of cardiac function or wall motion was proven by serial observational studies. Accordingly, several prospective randomized trials (RCTs), which should confirm such accumulated potential benefits, were recently conducted by comparison with studies of patients that had received optical medical therapy (OMT) alone. While they mostly demonstrated significant improvement of angina symptoms and quality of life (QOL) in the CTO-PCI group, they failed to prove a reduction of clinical events or improvement of left ventricle wall motion, compared with OMT. Concurrent guidelines or consensus documents emphasize that the principal indication for CTO-PCI is to improve symptoms. To determine strategy, the following must be discussed in each individual case: the probability of procedural success, the expectation of long-term patency, and an assessment of the balance between procedure-related complications and overall benefits. In essence, we believe the following facts to be the current sincere appraisal of CTO-PCI: (1) improvements of symptoms and QOL are established, but the others remain inconclusive, and; (2) their margins for improvement are narrowing and numbers of candidates are shrinking. Precision medicine or individualization may be the right directions to take, to enhance the potential of this treatment. This course of action demands discrimination of those candidates who will truly receive benefits from invasive treatment, and that still requires further clinical studies or actions.

Chronic total occlusion percutaneous coronary intervention in everyday clinical practice - an expert opinion of the Association of Cardiovascular Interventions of the Polish Cardiac Society

Coronary chronic total occlusions (CTO) are increasingly encountered during invasive and non-invasive coronary angiography and remain the most challenging lesions for percutaneous revascularization. During recent years success rates and safety outcomes of CTO percutaneous coronary intervention (PCI) have substantially improved, particularly due to the introduction of new techniques and dedicated equipment as well as specialized training programs of CTO operators. Significantly, the steady advances in CTO PCI techniques have coincided with the new data from randomized clinical trials supporting the role of percutaneous recanalization of CTO in relieving angina and improving the quality of life. The current expert consensus document outlines the rationale, clinical outcomes as well as technical, safety and reimbursement issues of CTO PCI. In addition, the requirements for achieving and maintaining competency in CTO PCI among interventional cardiologists are discussed. Finally, we present the modified hybrid algorithm (the so-called Polish hybrid algorithm) providing some unique refinements to the contemporary CTO PCI strategies. Continuous efforts (including active engagement with the payer) are urgently needed to increase guideline-recommended referrals to CTO PCI, and thus improve the quality of life of CTO patients in Poland.

Predictors and complications of side branch occlusion after recanalization of chronic total occlusions complicated with bifurcation lesions

Data on risk factors and periprocedural complications associated with side branch (SB) occlusion after chronic coronary total occlusion (CTO) recanalization are limited. The aims of this study were to identify independent predictors of side branch (SB) occlusion after chronic total occlusion (CTO) recanalization and assess the relationship between SB occlusion and perioperative complications. 245 patients with CTO bifurcation lesions (BFLs) who underwent successful CTO recanalization were included in the study. In the occlusion group, most of the SB occlusions were observed after the implantation of the stents and lack of SB protection was more common. However, there was no significant between-group difference in the angles between the main vessel (MV) and SB. SB occlusion was associated with a higher risk of periprocedural myocardial infarction and a higher composite periprocedural complication rate. Identified as predictors of SB occlusion were no SB protection, use of a dissection-reentry strategy, ostial SB stenosis, and proximal MV stenosis of 50% or more.

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.