Chronic total occlusions and coronary artery bypass grafting outcomes

OBJECTIVE

To investigate the association between the presence and grafting of chronic total occlusions (CTOs) and coronary artery bypass grafting (CABG) outcomes.

METHODS

This was a post hoc analysis of the Randomized Endograft vs Open Prospective (REGROUP) trial, which randomized veterans undergoing isolated on-pump CABG to endoscopic versus open vein harvest (2014-2017). Patients were stratified on the basis of the presence of at least 1 CTO vessel (a 100% occluded coronary lesion for greater than or equal to 3 months) and according to whether all CTO vessels were bypassed. Rates of major cardiac adverse events (MACE) were compared.

RESULTS

At least 1 CTO was present in 453 of 1149 patients (39.4%). Over a median follow-up of 4.7 years (interquartile range, 3.84-5.45), MACE rates were 23.4% versus 22.2% for the CTO versus no CTO group, respectively (adjusted hazard ratio [aHR], 0.92; 95% confidence interval [CI], 0.70-1.20). MACE rates for patients with complete CTO grafting versus not were 23.1% versus 25.0%, respectively (aHR, 0.95; 95% CI, 0.57-1.57). In patients with right coronary dominance undergoing left anterior descending artery grafting, bypassing a right coronary artery CTO was associated with significantly lower rates of all-cause mortality (aHR, 0.38; 95% CI, 0.17-0.83).

CONCLUSIONS

In this REGROUP trial subanalysis, neither CTO presence or complete grafting of CTO vessels was associated with significantly different rates of MACE. However, the finding of possible survival benefit among a subgroup of patients undergoing grafting of a dominant RCA CTO vessel alongside left anterior descending artery grafting warrants additional study.

Is it Worthy Enough to Revascularize Chronically Occluded Coronaries?

Chronic total occlusions (CTOs) represent the "final frontier" of coronary interventions with the lowest procedural success rates and the most common reason for incomplete revascularization and referral to coronary artery bypass graft surgery (CABG). CTO lesions are not an infrequent finding during coronary angiography. They are often responsible for enhancing the complexity of the coronary disease burden thereby affecting the final interventional decision in the process. Notwithstanding the modest technical success of CTO-PCI, most of the earlier observational data demonstrated a clear survival benefit free of major cardiovascular events (MACE) in patients undergoing successful CTO revascularization. However, data from recent randomized trials fail to uphold the same survival advantage albeit, showing some trend toward improvement in left ventricular function, quality of life indicators and freedom from fatal ventricular arrythmia. Various guidance statements propose a well-defined role for CTO intervention in specific situations provided criterions for patient selection, appreciable inducible ischemia, myocardial viability and cost-risk-benefit analysis are met.

Gender-Based Differences in Outcomes After Percutaneous Coronary Intervention of Chronic Total Occlusions (Insights from a Large Single-Center Registry)

Patients who undergo percutaneous coronary intervention (PCI) of chronic total occlusions (CTO) are at a high risk for both periprocedural and post-procedural adverse events. Whether gender-differences in outcomes exist after PCI of CTO remain unclear. Therefore, we sought to investigate gender-based differences in outcomes after CTO-PCI. All patients who underwent elective CTO intervention from January 2012 to December 2017 at The Mount Sinai Hospital (New York, New York) were included. The primary end point of interest was major adverse cardiac events defined as the composite of death, myocardial infarction, and target vessel revascularization at 1 year of follow-up. A total 1,897 patients were included, of which 368 were women (19.4%). Mean follow-up time was 174 days. Women were older (66.8 ± 11.3 years vs 62.6 ± 10.9 years) and had a higher prevalence of co-morbidities including diabetes and chronic kidney disease. There were no significant differences in the rate of successful CTO-PCI between groups (73.5% vs 73.2%, p = 0.91). Women had higher rates of procedure-related complications including increased risk of post-procedural bleeding (4.1% vs 1.8%, p = 0.009) and acute vessel closure (1.36% vs 0.2%, p = 0.009). In multivariable-adjusted analysis, female gender was associated with higher risk of major adverse cardiac event and target vessel revascularization at 1 year. In conclusion, in this large single-center study, women who underwent percutaneous CTO revascularization experienced higher rates of periprocedural complications and worse clinical outcomes at 1 year compared with men. Further research is needed to address disparities in gender-specific outcomes of CTO-PCI.

Association of Successful Percutaneous Revascularization of Chronic Total Occlusions With Quality of Life: A Systematic Review and Meta-Analysis

Importance

Chronic total occlusion percutaneous coronary intervention (CTO-PCI) is not usually offered because of skepticism about long-term clinical benefits.

Objective

To assess the association of successful CTO-PCI with quality of life by analyzing the relevant domains of the Seattle Angina Questionnaire (SAQ).

Data Sources

PubMed, EMBASE, Web of Science, Google Scholar, and Cochrane databases were searched to identify randomized trials and observational studies specifically addressing quality of life domains of SAQ from January 2010 to June 2022.

Study Selection

Studies included reporting SAQ metrics such as angina frequency, physical limitation, and quality of life, before and after CTO-PCI.

Data Extraction and Synthesis

The present study was performed according to the Cochrane Collaboration and Preferred Reporting Items for Systematic Reviews and Meta-Analyses statements, in which fixed-effect or random-effect models with generic inverse-variance weighting depending on statistical homogeneity were applied. Data were extracted by 3 independent reviewers.

Outcomes and Measures

The primary outcome was angina frequency; physical limitation and quality of life were assessed as secondary outcomes.

Results

Seven prospective randomized or observational studies (2500 patients) were included, with a mean (SD) participant age of 61.2 (2.1) years. CTO-PCI was associated with significantly improved quality-of-life metrics during a mean (SD) follow-up of 14.8 (16.3) months. In patients with successful procedures, angina episodes became less frequent (mean [SD] difference for SAQ angina frequency of 12.9 [3.1] survey points [95% CI, 7.1-19.8 survey points]; standardized mean difference was 0.54 [95% CI, 0.21-0.92]; P = .002; I2 = 86.4%) and they experienced less physical activity limitation (mean [SD] difference for SAQ physical limitation of 9.7 [6.2] survey points [95% CI, 3.5-16.2 survey points]; standardized mean difference was 0.42 [95% CI, 0.24-0.55]; P < .001; I2 = 20.9%), and greater quality-of-life domain (mean [SD] difference for SAQ quality of life of 14.9 [3.5] survey points [95% CI, 7.7-22.5 survey points]; standardized mean difference was 0.41 [95% CI, 0.25-0.61]; P < .001; I2 = 58.8%) compared with patients with optimal medical therapy or failed procedure. Furthermore, follow-up duration (point estimate, 0.03; 95% CI, 0.01-0.04; P = .01) was associated with a significant decrease in angina frequency in meta-regression analysis.

Conclusions and Relevance

In this systematic review and meta-analysis examining quality of life following CTO-PCI, successful procedures were associated with improved quality-of-life parameters compared with patients on optimal medical therapy or after failed CTO-PCI. These findings suggest support for using PCI to treat CTOs in symptomatic patients unresponsive to medical treatment.

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.

Relationship between dynamic changes of peri-procedure anxiety and short-term prognosis in patients undergoing elective percutaneous coronary intervention for coronary heart disease: A single-center, prospective study

Background

Patients with coronary heart disease (CHD) often experience anxiety, but the current studies on anxiety mostly focused on a certain point in time. Therefore, this study aimed to investigate the dynamic changes of peri-procedure anxiety, status of post-procedure quality of life, and cardiovascular readmission rates in patients with CHD who undergoing elective percutaneous coronary intervention (PCI), and to analyze the influence of peri-procedure anxiety on quality of life and readmission rate after PCI.

Methods

This prospective study was conducted at Changshu NO.1 People’s Hospital. A total of 220 patients with CHD undergoing elective PCI were selected as study subjects. The general information, clinical data, anxiety, quality of life and readmission of patients were collected. Multivariate linear regression was used to examine the effect of peri-procedure anxiety on quality of life, and multivariate logistic regression was used to analyze the influence of peri-procedure anxiety on readmission rate.

Results

This study showed the anxiety scores at hospitalization appointment(T1), 3 days before procedure(T2), 1 day before procedure(T3), 1 day after procedure(T4) were 57(55,61),64(61,68),54(51.58), and 54(50,60), respectively. And, at 3 months and 6 months after PCI, the scores of Seattle Angina Questionnaire (SAQ) were 346.61(319.06,366.52) and 353.34(334.18,372.84) respectively. During 6 months follow-up, 54 cases were readmitted, with a readmission rate of 25.5%. Statistical analysis showed that T1 with anxiety (P = 0.002) and T2 with anxiety (P = 0.024) were independent risk factors for treatment satisfaction at 3 months after PCI. Anxiety in T4 (P = 0.005) was an independent risk factor on the angina frequency at 6 months after PCI. T2 with anxiety (B = 1.445, P = 0.010, 95%CI:1.409–12.773) and T4 without anxiety (B = -1.587, P = 0.042, 95%CI:-0.044–0.941) were risk factors affecting readmission for cardiovascular reasons within 6 months.

Conclusion

Patient anxiety at T1 and T2 affects the treatment satisfaction dimension of the SAQ at 3 months after PCI, and anxiety at T4 affects the angina frequency dimension of the SAQ at 6 months after PCI. Anxiety at T2 and no anxiety at T4 increase short-term readmission rates. In the future, interventions should be strengthened at various time points in the peri-procedure period to improve post-procedure rehabilitation effect.

Canadian Multicenter Chronic Total Occlusion Registry: Ten-Year Follow-Up Results of Chronic Total Occlusion Revascularization

BACKGROUND

Chronic total occlusions (CTO) occur in nearly 20% of coronary angiograms. CTO revascularization, either by percutaneous coronary intervention (PCI) or coronary artery bypass grafting surgery (CABG), is infrequently performed, approximately one-third of cases. Long-term outcomes are unknown. The objective of the study was to determine whether early CTO revascularization of patients, either by CABG or PCI, was associated with improved clinical outcomes.

METHODS

One thousand six hundred twenty-four patients from the Canadian CTO registry were followed for at least 9.75 years. Revascularization was performed according to routine clinical practice. Patients were grouped according to CTO revascularization status (PCI or CABG of CTO vessel, CTO revasc) or no CTO revasc (medical therapy only, or PCI/CABG of non-CTO vessels only), within 3 months of initial angiogram. Patients were followed for mortality, revascularization procedures (PCI and CABG), and hospitalizations for acute coronary syndromes and heart failure.

RESULTS

Early CTO revasc was performed in 28.2% of patients (17.5% CABG, 10.7% PCI). The CTO revasc group was younger, with more males and generally fewer comorbidities. There was a significantly lower mortality probability at 10 years in the CTO revascularization group (22.7% [95% CI, 19.0%-26.9%]) compared with the no CTO revasc group (36.6% [95% CI, 33.8%-39.5%]). At 10 years, revascularization rates (14.0% versus 22.8%) and acute coronary syndrome hospitalization rates (10.0% versus 16.6%) were significantly lower in the CTO revasc group. Baseline-adjusted analysis showed CTO revasc was associated with significantly lower all-cause mortality (hazard ratio, 0.67 [95% CI, 0.54-0.84]). In both landmark and time varying analyses, association with lower mortality was particularly robust for CTO revascularization by CABG (hazard ratio 0.56 and 0.60, respectively), with a marginally significant result for PCI in the time varying analysis (hazard ratio 0.711 [95% CI, 0.51-0.998]).

CONCLUSIONS

Early CTO revascularization was associated with significantly lower all-cause mortality, revascularization rates, and hospitalization for acute coronary syndrome at 10 years, and mainly driven by outcomes in patients with CABG.

Preprocedural computed tomography angiography in differentiating chronic total from subtotal coronary occlusions

INTRODUCTION

Differentiation of chronic total occlusion (CTO) from subtotal coronary occlusions (STOs) is often difficult to make from coronary angiography. These differences are very important, as the technical expertise and tools required are significantly different for revascularization of these lesions. We sought to determine if preprocedural computed tomography angiography (CTA) can help better diagnose and differentiate CTO from STO.

METHODS

We searched three databases (Ovid MEDLINE, EMBASE, EBM reviews) from 1 January 1946 to 1 March 2019. Studies reporting on the use of computed tomography (CT) to aid in CTO revascularization were included. Case reports and case series were excluded.

RESULTS

We identified 577 articles, and using the Preferred Reporting Items for Systematic Reviews and Meta-analyses method, 4 articles met prespecified inclusion criteria. A total of 669 patients were included. The statistically significant CT-derived parameters determined to help differentiate CTO from STO were found to include longer lesion length (four out of four studies), larger contrast density difference (one out of four studies), presence of collaterals (two out of four studies) and the presence of the reverse attenuation gradient sign (two out of four studies).

CONCLUSION

This systematic review shows the utility of preprocedural CTA to help differentiate CTO from STO using a number of CT-derived parameters as above. Further, this study highlights the need for further research to develop specific validated parameters for differentiation of CTO and STO.

Both surgical and percutaneous revascularization improve prognosis in patients with a coronary chronic total occlusion (CTO) irrespective of collateral robustness

The impact of surgical or percutaneous coronary revascularization on prognosis in patients with a chronic total occlusion (CTO) remains uncertain. Particularly, whether revascularization of those with robust coronary collaterals improves prognosis is unknown. The objective of this study was to determine the predictors and prognostic impact of revascularization of a CTO, and to determine the clinical impact of robust coronary collaterals. Patients with a CTO diagnosed on coronary angiography between Jul 2010 and Dec 2019 were included in this study. Management strategy of the CTO was defined as percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG) or medical management. The degree of collateral robustness was determined by the Rentrop grading classification. Demographic, angiographic and clinical outcomes were recorded. A total of 954 patients were included in the study, of which 186 (19.5%) patients underwent CTO PCI, 296 (31.0%) patients underwent CABG and 472 (49.5%) patients underwent medical management of the CTO. 166 patients (17.4%) had Rentrop grade zero or one collaterals, 577 (60.5%) patients had Rentrop grade two and 211 (22.1%) had Rentrop grade three collaterals. The independent predictors of medical management of the CTO were older age, greater stenosis in the donor vessel, an emergent indication for angiography, a non-LAD CTO and female sex. The degree of collateral robustness was not associated with long-term mortality, while patients who were revascularized either through CABG or PCI had a significantly lower mortality compared to medical management alone (p < 0.0001). In patients with a CTO, the presence of robust collaterals is not associated with prognosis, while both surgical and percutaneous revascularization is associated with improved prognosis. Further research into the optimal revascularization strategy for a CTO is required.

Two-year left ventricular systolic function of percutaneous coronary intervention vs optimal medical therapy for patients with single coronary chronic total occlusion

In this study, two-dimensional speckle tracking echocardiography (2D-STE) and real-time three-dimensional echocardiography (RT-3DE) were applied to compare the changes of left ventricular systolic function associated with percutaneous coronary intervention (PCI) versus optimal medical therapy (OMT) in patients with single chronic total occlusion (CTO). 63 single CTO patients (age 61.88 ± 8.86 years) were examined by echocardiography and were divided into the PCI group (n = 27) and OMT group (n = 36) according to the initial treatment strategy. Two-dimensional left ventricular ejection fraction (2D-LVEF), two-dimensional indexed left ventricular end-systolic volume (2D-LVESVI), and two-dimensional indexed left ventricular end-diastolic volume (2D-LVEDVI) were measured using two-dimensional echocardiography (2DE). Three-dimensional left ventricular ejection fraction (3D-LVEF), three-dimensional indexed left ventricular end-systolic volume (3D-LVESVI), and three-dimensional indexed left ventricular end-diastolic volume (3D-LVEDVI) were measured using RT-3DE. Global circumferential strain (GCS) and global longitudinal strain (GLS) were measured using 2D-STE. After 2 years of follow-up, there were no significant differences in the 2D-LVEF, 2D-LVESVI, 3D-LVEF, 3D-LVESVI, 3D-LVEDVI, and GCS, except for GLS (P = .001) between the CTO-PCI and CTO-OMT groups. GLS decreased significantly in OMT group (P = .016) in contrast with PCI group in which GLS increased significantly (P = .007). Left ventricular systolic function assessment using 2D-STE showed a significant difference in GLS between CTO-PCI and CTO-OMT. And the patients who chose PCI revascularization at the 2-year follow-up had better left ventricular systolic function improvement than those who were conservatively treated with OMT.

The Canadian Contribution to Science, Techniques, Technology, and Education in Chronic Total Occlusion Percutaneous Coronary Intervention

Chronic total occlusions are considered the most complex coronary lesions in interventional cardiology. This article reviews the Canadian clinical and academic contributions to this field, including innovative procedural techniques, teaching and proctoring, clinical research, and the development of novel tools and therapies.

Indications and Patient Selection for Percutaneous Coronary Intervention of Chronic Total Occlusions

The most common indication for chronic total occlusion (CTO) percutaneous coronary intervention (PCI) is angina relief, which translates into improved physical function and quality of life. As the risk of the procedure is higher compared with non CTO PCI, it is important for operators to understand the current state of literature and have a detailed discussion with patients regarding risks and benefits prior to the procedure. This article discusses indications for the procedure and how to appropriately select patients for CTO PCI, in hopes of inspiring the reader to consistently offer this approach to indicated patients regardless of anatomic complexity.

Impact of Renal Function on Long-Term Clinical Outcomes in Patients With Coronary Chronic Total Occlusions: Results From an Observational Single-Center Cohort Study During the Last 12 Years

Background: The number of coronary chronic total occlusion (CTO) patients with renal insufficiency is huge, and limited data are available on the impact of renal insufficiency on long-term clinical outcomes in CTO patients. We aimed to investigate clinical outcomes of CTO percutaneous coronary intervention (PCI) vs. medical therapy (MT) in CTO patients according to baseline renal function. Methods: In the study population of 2,497, 1,220 patients underwent CTO PCI and 1,277 patients received MT. Patients were divided into four groups based on renal function: group 1 [estimated glomerular filtration rate (eGFR) ≥ 90 ml/min/1.73 m²], group 2 (60 ≤ eGFR <90 ml/min/1.73 m²), group 3 (30 ≤ eGFR <60 ml/min/1.73 m²), and group 4 (eGFR <30 ml/min/1.73 m²). Major adverse cardiac event (MACE) was the primary end point. Results: Median follow-up was 2.6 years. With the decline in renal function, MACE (p < 0.001) and cardiac death (p < 0.001) were increased. In group 1 and group 2, MACE occurred less frequently in patients with CTO PCI, as compared to patients in the MT group (15.6% vs. 22.8%, p < 0.001; 15.6% vs. 26.5%, p < 0.001; respectively). However, there was no significant difference in terms of MACE between CTO PCI and MT in group 3 (21.1% vs. 28.7%, p = 0.211) and group 4 (28.6% vs. 50.0%, p = 0.289). MACE was significantly reduced for patients who received successful CTO PCI compared to patients with MT (16.7% vs. 22.8%, p = 0.006; 16.3% vs. 26.5%, p = 0.003, respectively) in group 1 and group 2. eGFR < 30 ml/min/1.73 m², age, male gender, diabetes mellitus, heart failure, multivessel disease, and MT were identified as independent predictors for MACE in patients with CTOs. Conclusions: Renal impairment is associated with MACE in patients with CTOs. For treatment of CTO, compared with MT alone, CTO PCI may reduce the risk of MACE in patients without chronic kidney disease (CKD). However, reduced MACE from CTO PCI among patients with CKD was not observed. Similar beneficial effects were observed in patients without CKD who underwent successful CTO procedures.

Association Between Revascularization and Quality of Life in Patients With Coronary Chronic Total Occlusions: A Systematic Review

BACKGROUND

Percutaneous revascularization of coronary chronic total occlusions (CTO) has increased due to advances in technology and operator expertise. Quality of life (QoL) remains an important but understudied outcome following CTO revascularization. Our aim is to conduct a systematic review of the impact of CTO revascularization on QoL.

METHODS

We searched three databases (Ovid MEDLINE, EMBASE, EBM reviews) from January 1st, 1990 to May 17th, 2020. Studies reporting on the following QoL metrics post CTO revascularization were included: QoL subscale of the Seattle Angina Questionnaire (SAQ-QoL). The ROBINS-I tool and Cochrane risk of bias tool were used to critically assess for risk of bias.

RESULTS

We identified 1476 articles, of which 21 articles met inclusion criteria. Three categories of studies were identified with distinct patient populations. In the first category (1 study), CTO patients treated with either PCI or CABG compared to medical therapy had a significant improvement in SAQ-QoL compared to baseline (PCI 54.2 to 74.3; CABG 56.1 to 78.0; p < 0.05). In the second category (1 study), CTO patients compared to non-CTO patients had similar improvements in SAQ-QoL post PCI (CTO baseline 53.2 to 80.3; non-CTO baseline 56.5 to 80.6; p < 0.05). Finally, a third category with only CTO patients treated with PCI to the CTO vessel included 19 studies, all of which on average showed a significant improvement in SAQ-QoL post successful PCI, compared to non-successful PCI.

CONCLUSION

Despite the limited literature, revascularization of CTO vessel was generally associated with improvement in QoL.

BRIEF SUMMARY

Quality of life (QoL) is an important but understudied outcome following CTO revascularization. We conducted a systematic review of the impact of CTO revascularization on QoL. Despite the limitations of a lack of enough randomized control trials and the small number of studies, our systematic review highlights a trend of improvement in QoL indices after revascularization of CTO.

Procedural, clinical, and health status outcomes in chronic total coronary occlusion revascularization: Results from the PERSPECTIVE study

BACKGROUND

Limited research has detailed the outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) with independent core laboratory and event adjudication. This study examined procedural, clinical, and patient-reported health status outcomes among patients undergoing CTO PCI with specific focus on outcomes for those treated with zotarolimus-eluting stents (ZES).

METHODS

Among 500 consecutive patients undergoing attempted CTO PCI, procedural and in-hospital clinical outcomes were examined in addition to the 1-year composite endpoint of death, myocardial infarction, and target lesion revascularization (major adverse cardiac events, MACE). In a pre-specified cohort of 250 patients, health status measures were ascertained at baseline and 1 year. A powered secondary endpoint was 1-year MACE among patients treated with ZES compared with a performance goal.

RESULTS

Demographic, lesion, and procedural characteristics for the overall population included prior bypass surgery, 29.8%; diabetes, 35.2%; occlusion length >20 mm, 71.3%; J-CTO score, 2.5 ± 1.1; and primary retrograde strategy, 30.8%. Overall guidewire crossing was 90.9%; clinical success following guidewire crossing, 94.3%; and 1-year MACE rate, 12.1%. One-year health status significantly improved from baseline with successful CTO-PCI (angina frequency, 72.7 ± 26.5 at baseline to 96.0 ± 10.8, p < .0001). Compared with a performance goal derived from prior CTO DES trials (1-year hierarchal MACE, 25.2%), treatment with ZES was associated with significantly lower MACE (18.2%, one-sided upper CI, 23.6%, p = .017).

CONCLUSIONS

Favorable procedural success, health status improvements and late-term clinical outcomes inform the relative risks and benefits of CTO PCI when performed in a clinically indicated, complex patient population representative of those treated in clinical practice.

Percutaneous coronary intervention provided better long term results than optimal medical therapy alone in patients with chronic total occlusion: A meta-analysis

AIMS

Studies comparing the outcome of percutaneous coronary intervention (PCI) along with optimal medical therapy (OMT) versus OMT alone in treatment of chronic total occlusion (CTO) are limited by observational design, variable follow-up period, diverse clinical outcomes, high drop-out and cross-over rates. This study aims to conduct a meta-analysis of published data of observational as well as randomized studies comparing long term outcomes of PCI+OMT versus OMT alone.

METHODS AND RESULTS

PubMed, Embase and Cochrane databases were systematically reviewed. 15 studies meeting criteria were included in the meta-analysis. The New-castle Ottawa scale was used to appraise the overall quality of the studies. Random-effects model with inverse variance method was undertaken. Major adverse cardiovascular events (MACE) which comprises of cardiac death, myocardial infarction, stroke, and un-planned revascularization were significantly lower in the PCI+OMT group (RR:0.76; 95% CI:0.61 to 0.95; P=<0.00001; I² = 85%). All-cause mortality and cardiac death were significantly lower in the PCI+OMT group (P=<0.00001 in both). Myocardial infarction and stroke rates were lower in the PCI+OMT group, however they did not reach statistical significance (P = 0.24, P = 0.15 respectively). Unplanned revascularizations (of any vessel) were also similar in both the groups (P = 0.78, I² = 88%).

CONCLUSION

PCI of CTO is rewarded with better long term outcome, in terms of MACE, all-cause mortality and cardiac death with similar rates of un-planned revascularization.

Long-Term Outcomes of Successful Revascularization for Patients With Coronary Chronic Total Occlusions: A Report of 1,655 Patients

Background: To date, the benefit of successful revascularization of chronic total occlusions (CTOs) on prognosis remains uncertain, and there is a paucity of data on the impact of successful revascularization for CTO patients on long-term cardiovascular survival. This study aimed to investigate the long-term cardiovascular survival for patients with successful and unsuccessful CTO revascularization in a large cohort of patients.

Methods: There were 1,655 consecutive patients with at least one CTO included and were grouped into successful revascularization (n = 591) and unsuccessful revascularization (n = 1,064). Propensity score matching (PSM) was carried out to balance the clinical and the angiographic characteristics. Cardiac mortality was defined as the primary endpoint. Major adverse cardiac event (MACE) was assessed as a “secondary endpoint.”

Results: After 3.6 years of follow-up, there was no significant difference between the successful and the unsuccessful revascularization groups in the rate of cardiac mortality [adjusted hazard ratio (HR) 0.96, 95% confidence interval (CI) 0.59–1.58, p = 0.865]. After the PSM analysis (371 pairs) between the two groups, the cardiac mortality rate values (HR 0.51, 95% CI 0.23–1.15, p = 0.104) were equivalent, whereas the adjusted risk of MACE (HR 0.43, 95% CI 0.32–0.58, p = 0.001) and target-vessel revascularization (HR 0.41, 95% CI 0.29–0.58, p < 0.001) were significantly higher in patients with unsuccessful revascularization.

Conclusion: For the treatment of CTO patients, successful revascularization was not associated with a lesser risk for cardiac mortality as compared with unsuccessful revascularization. However, successful revascularization reduced MACE and target-vessel revascularization.

Prompt and consistent improvement of coronary flow velocity reserve following successful recanalization of the coronary chronic total occlusion in patients with viable myocardium

Background

Coronary chronic total occlusion (CTO) is characterized by the presence of collateral blood vessels which can provide additional blood supply to CTO-artery dependent myocardium. Successful CTO recanalization is followed by significant decrease in collateral donor artery blood flow and collateral derecruitment, but data on coronary hemodynamic changes in relation to myocardial function are limited. We assessed changes in coronary flow velocity reserve (CFVR) by echocardiography in collateral donor and recanalized artery following successful opening of coronary CTO.

Methods

Our study enrolled 31 patients (60 ± 9 years; 22 male) with CTO and viable myocardium by SPECT scheduled for percutaneous coronary intervention (PCI). Non-invasive CFVR was measured in collateral donor artery before PCI, 24 h and 6 months post-PCI, and 24 h and 6 months in recanalized artery following successful PCI of CTO.

Results

Collateral donor artery showed significant increase in CFVR 24 h after CTO recanalization compared to pre-PCI values (2.30 ± 0.49 vs. 2.71 ± 0.45, p = 0.005), which remained unchanged after 6-months (2.68 ± 0.24). Baseline blood flow velocity of the collateral donor artery significantly decreased 24 h post-PCI compared to pre-PCI (0.28 ± 0.06 vs. 0.24 ± 0.04 m/s), and remained similar after 6 months, with no significant difference in maximum hyperemic blood flow velocity pre-PCI, 24 h and 6 months post-PCI. CFVR of the recanalized coronary artery 24 h post-PCI was 2.55 ± 0.35, and remained similar 6 months later (2.62 ± 0.26, p = NS).

Conclusions

In patients with viable myocardium, prompt and significant CFVR increase in both recanalized and collateral donor artery, was observed within 24 h after successful recanalization of CTO artery, which maintained constant during the 6 months.

Trial registration

ClinicalTrials.gov (Number NCT04060615).

A randomized multicentre trial to compare revascularization with optimal medical therapy for the treatment of chronic total coronary occlusions

Aims

The clinical value of percutaneous coronary intervention (PCI) for chronic coronary total occlusions (CTOs) is not established by randomized trials. This study should compare the benefit of PCI vs. optimal medical therapy (OMT) on the health status in patients with at least one CTO.

Method and results

Three hundred and ninety-six patients were enrolled in a prospective randomized, multicentre, open-label, and controlled clinical trial to compare the treatment by PCI with OMT with a 2:1 randomization ratio. The primary endpoint was the change in health status assessed by the Seattle angina questionnaire (SAQ) between baseline and 12 months follow-up. Fifty-two percent of patients have multi-vessel disease in whom all significant non-occlusive lesions were treated before randomization. An intention-to-treat analysis was performed including 13.4% failed procedures in the PCI group and 7.3% cross-overs in the OMT group. At 12 months, a greater improvement of SAQ subscales was observed with PCI as compared with OMT for angina frequency [5.23, 95% confidence interval (CI) 1.75; 8.71; P = 0.003], and quality of life (6.62, 95% CI 1.78-11.46; P = 0.007), reaching the prespecified significance level of 0.01 for the primary endpoint. Physical limitation (P = 0.02) was also improved in the PCI group. Complete freedom from angina was more frequent with PCI 71.6% than OMT 57.8% (P = 0.008). There was no periprocedural death or myocardial infarction. At 12 months, major adverse cardiac events were comparable between the two groups.

Conclusion

Percutaneous coronary intervention leads to a significant improvement of the health status in patients with stable angina and a CTO as compared with OMT alone.

Trial registration

NCT01760083.

Health Status Benefits of Successful Chronic Total Occlusion Revascularization Across the Spectrum of Left Ventricular Function: Insights From the OPEN-CTO Registry

OBJECTIVES

This study sought to describe the association between chronic total occlusion (CTO) revascularization (CTO percutaneous coronary intervention [PCI]) and health status in patients with and without cardiomyopathy.

BACKGROUND

Prior PCI trials for cardiomyopathy have excluded CTO patients. Whether patients with reduced left ventricular ejection fraction (LVEF) receive similar health status benefit from CTO-PCI compared with patients with normal LVEF is unclear.

METHODS

We assessed health status change, using the Seattle Angina Questionnaire (SAQ) Summary, SAQ Angina Frequency, and Rose Dyspnea Scale scores, among patients undergoing successful CTO PCI in the OPEN-CTO (Outcomes, Patient Health Status, and Efficiency in Chronic Total Occlusion) Registry. Participants were classified by LVEF (normal, ≥50%; mild-moderate, 30% to 49%; and severe, <30%), with higher SAQ and lower Rose Dyspnea Scale scores indicating better health status. Differences in 1-year outcomes were compared using hierarchical multivariable regression.

RESULTS

Of 762 patients, 506 (66.4%), 193 (25.3%), and 63 (8.3%) had normal, mild-moderate, and severely reduced LVEF. SAQ Summary score improvements were observed in each group (27.1 ± 20.4, 26.7 ± 21.2, and 20.3 ± 18.1, respectively). Compared with patients with LVEF ≥50%, those with LVEF <30% had less improvement in SAQ Summary Score (-5.2 points; 95% confidence interval: -9.0 to -1.5; p = 0.01) and Rose Dyspnea Scale (+0.5 points; 95% confidence interval: 0.1 to 0.8; p = 0.01), with no difference in odds of angina (odds ratio: 1.3; 95% confidence interval: 0.6 to 3.0; p = 0.48). Health status improvement was similar between patients with LVEF ≥50% and LVEF 30% to 49%.

CONCLUSIONS

Although health status improvement was less in patients with severely reduced LVEF compared with those with normal LVEF, each group experienced large health status improvements after CTO-PCI.

Current approaches for treatment of coronary chronic occlusions

Introduction: Coronary chronic total occlusions (CTO) represent a challenging subset in interventional cardiology.Areas covered: During the last decade, improvements in materials, techniques, and meticulous pre-procedural lesion assessment have increased the success rate in CTO lesions. Several scores have been developed to address overall lesion evaluation and help select the most appropriate treatment strategy. In addition, specific algorithms such as the hybrid algorithm have been introduced to provide a framework for CTO operators and a rapid management of the various challenging aspects of the procedure. The hybrid approach requires operator's ability to switch from one treatment strategy to another when the first one appears to be unsuccessful. Adequate training and operators' experience remain crucial to improve the likelihood of success.Expert opinion: The aim of this review is to provide insights and guidance for operators on current approaches for treatment of CTO and complication management.

Successful recanalisation of coronary chronic total occlusions is not associated with improved cardiovascular survival compared with initial medical therapy

Objective. To compare the clinical outcomes associated with successful percutaneous coronary intervention (PCI) versus initial medical therapy (MT) in patients with coronary chronic total occlusions (CTOs). Methods. Between January 2007 and December 2016, a total of 1702 patients with ≥1 CTO were enrolled. Patients who had a failed CTO-PCI were excluded. After exclusion, 1294 patients with 1520 CTOs were divided into the MT group initially (did not undergo a CTO-PCI attempt) (n = 800) and successful PCI group (n = 494). Propensity-score matching was also performed to adjust for baseline characteristics. The primary outcome was cardiac death. Results. The median overall follow-up duration was 3.6 (IQR, 2.1-5.0) years, there was no significant difference between the two groups with respect to the prevalence of cardiac death (MT vs. successful PCI: 6.6 vs. 3.8%, adjusted hazard ratio [HR] 0.93, 95% confidence interval [CI] 0.41-2.14, p = .867). In the propensity-matched population (286 pairs), there were no significant differences in the prevalence of cardiac death (MT vs. successful PCI: 5.9% vs. 3.1%, HR 0.51, 95% CI 0.23-1.15, p = .104) and major adverse cardiovascular events (MACE) (HR 0.76, 95% CI 0.53-1.09, p = .130) between the two groups. Conclusion. In the treatment of patients with CTOs, successful PCI is not associated with improved long-term cardiovascular survival or reduced the risk of MACE compared with MT alone initially.

Trajectories of Health-Related Quality of Life in Coronary Artery Disease

BACKGROUND

Health-related quality of life (HRQOL) assessment is an important health outcome for measuring the efficacy of treatments and interventions for coronary artery disease (CAD). HRQOL is known to improve over the first year after interventions for CAD, but there is limited knowledge of the changes in HRQOL beyond 1 year. We investigated heterogeneity in long-term trajectories of HRQOL in patients with CAD.

METHODS AND RESULTS

Data were obtained from 6226 patients identified from the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease with at least 1-vessel CAD who underwent their first catheterization between 2006 and 2009. HRQOL was assessed using the Seattle Angina Questionnaire, a 19-item disease-specific measure of HRQOL for patients with CAD. Group-based trajectory analysis was used to identify various subgroups of Seattle Angina Questionnaire trajectories over time while adjusting for missing data through a longitudinal multiple imputation model. Multinomial logistic regression was used to identify the predictors of differences among the identified subgroups. Our analysis revealed significant improvements in HRQOL across all the 5 domains of Seattle Angina Questionnaire overtime for the whole data. Multitrajectory analyses revealed 4 HRQOL trajectory subgroups including high (25.1%), largely increased (32.3%), largely decreased (25.0%), and low (17.6%) trajectories. Age, sex, body mass index, diabetes mellitus, previous history of myocardial infarction, smoking, depression, anxiety, type of treatment received, and perceived social support were significant predictors of differences among these trajectory subgroups.

CONCLUSIONS

This study highlights variations in longitudinal trajectories of HRQOL in patients with CAD. Despite overall improvements in HRQOL, about a quarter of our cohort experienced a significant decline in their HRQOL over the 5-year period. Understanding these HRQOL trajectories may help personalize prognostic information, identify patients and HRQOL domains on which clinical interventions are most beneficial, and support treatment decisions for patients with CAD.

Two-year clinical outcomes of medical therapy vs. revascularization for patients with coronary chronic total occlusion

OBJECTIVES

There are little data on the long-term clinical outcomes of medical therapy (MT) compared with revascularization in patients with chronic total occlusions (CTOs).

METHODS

Between January 2007 and December 2016, a total of 1655 patients with ≥1 CTO were enrolled in our center and were divided into the MT group (n = 800) and revascularization group (n = 855) according to the initial treatment strategy. Propensity score matching was also performed to adjust for baseline characteristics. The primary outcome was cardiac death.

RESULTS

After 2 years of follow-up, there was no significant difference between the two groups with regard to the prevalence of cardiac death (MT vs. revascularization: 6.6% vs. 4.2%, adjusted hazard ratio [HR] 0.95, 95% confidence interval [CI] 0.60-1.49, p = 0.820). In the propensity-matched population (406 pairs), there were no significant differences in the prevalence of cardiac death (MT vs. revascularization: 5.4% vs. 4.7%, HR 0.88, 95% CI 0.48-1.63, p = 0.694), except for target vessel revascularization (TVR) (0.44, 0.31-0.63, <0.001) and major adverse cardiovascular events (MACE) (0.51, 0.38-0.68, <0.001), between the two groups. There were also no significant differences in the prevalence of cardiac death (MT vs. successful CTO-PCI: 6.6% vs. 4.0%, HR 0.94, 95% CI 0.41-2.15, p = 0.881) between the MT and successful CTO-PCI groups.

CONCLUSION

As an initial management strategy in patients with CTOs, revascularization did not reduce the risk of cardiac death compared with treatment with medical therapy alone. However, revascularization was associated with reduction in the prevalence of TVR and MACE. Furthermore, successful CTO-PCI was also not associated with improved long-term survival compared with MT alone.

Role of Percutaneous Chronic Total Occlusion Interventions in Patients with Ischemic Cardiomyopathy and Reduced Left Ventricular Ejection Fraction

PURPOSE OF REVIEW

The purpose of this review is to examine current evidence on the benefit of chronic total occlusion (CTO) revascularization in patients with ischemic cardiomyopathy and propose a systematic approach on how and when to accomplish revascularization in these patients.

RECENT FINDINGS

Coronary revascularization in patients with reduced ejection fraction (EF) is advocated for to improve left ventricular function and consequently clinical outcomes. Approximately 16-31% of angiograms in patients with advanced CAD are noted to have a concomitant coronary CTO. Its presence is a main predictor of worse outcomes. Over the past 15 years, advancements in interventional technologies and techniques have made it possible to treat CTO lesions percutaneously with success rates exceeding 90%. Different revascularization techniques have been organized into widely used algorithms for systematic CTO lesion crossing and treatment. Patients with reduced EF can be revascularized percutaneously with goal of complete functional revascularization. However, randomized prospective data is needed to justify the increased patient risks and healthcare costs associated with these procedures.

Percutaneous coronary intervention versus optimal medical therapy for patients with chronic total occlusion: a meta-analysis and systematic review

Background

It was under debate whether chronic total occlusion (CTO) patients could benefit from percutaneous coronary intervention (PCI). We sought to compare clinical outcomes of PCI and optimal medical therapy (OMT) in these patients.

Methods

PubMed, Embase and Cochrane Library were searched for studies enrolling patients with CTO who accepted PCI or OMT. The meta-analysis was performed by using a random-effect model. In addition, subgroup analyses were performed, including patients after propensity-matching and patients with CTO in infarct-related artery (IRA), respectively.

Results

We identified 5 studies enrolling 4,761 participants in this meta-analysis. In the main analysis, when compared with OMT, PCI was associated with significant improvement in all-cause death [risk ratio (RR) 0.41, 95% CI: 0.35-0.48], cardiac death (RR 0.44, 95% CI: 0.35-0.55) and major adverse cardiac events (MACE) (RR 0.64, 95% CI: 0.43-0.97). But there were no differences in myocardial infarction (MI) and stroke. The results of the propensity-matched subgroup were somewhat consistent with those of the main analysis (all-cause death: RR 0.57, 95% CI: 0.26-0.89; MI: RR 0.54, 95% CI: 0.32-0.77; and MACE: RR 0.76, 95% CI: 0.33-1.18). In IRA subgroup, PCI reduced risks of mortality (all-cause death: RR 0.41, 95% CI: 0.34-0.49; cardiac death: RR 0.44, 95% CI: 0.35-0.56) and MACE (RR 0.71, 95% CI: 0.46-1.10). But no difference was observed in MI.

Conclusions

PCI was associated with improved survival and reduced MACE relative to OMT.

Percutaneous Coronary Intervention of Chronic Total Occlusions in Patients With Low Left Ventricular Ejection Fraction

OBJECTIVES

The study sought to assess the outcome of percutaneous coronary intervention (PCI) of chronic total occlusions (CTOs) in patients with low left ventricular ejection fraction (LVEF) (≤35%).

BACKGROUND

Data regarding the outcome of PCI in patients with low LVEF affected by CTO are scarcely reported.

METHODS

The authors performed a prospective longitudinal multicenter study including consecutive patients undergoing elective PCI of CTOs. Patients were subdivided into 3 groups: group 1 (LVEF ≥50%), group 2 (LVEF 35% to 50%), and group 3 (LVEF ≤35%).

RESULTS

A total of 839 patients (mean 64.6 ± 10.5 years of age, 87.7% men) underwent CTO PCI attempts. Baseline LVEF ≤35% was present in 72 (8.6%) patients. The angiographic success was high (overall 93.6%) and similar among the 3 groups (93.5% vs. 94.4% vs. 91.7%, respectively; all p = NS). In group 3, no periprocedural complications of CTO PCI were observed. Mean clinical follow-up of 16.3 ± 8.2 months duration was available in 781 (93.1%) patients including those with LVEF ≤35%. At 2 years, major cardiac and cerebrovascular events (MACCE) free survival was similar in the 3 groups (86% vs. 82.8% vs. 75.2%; all p = NS). In patients with LVEF ≤35%, LVEF improved significantly in the presence of a successful CTO PCI from 29.1 ± 3.4% to 41.6 ± 7.9% (p < 0.001).

CONCLUSIONS

In CTO patients with low LVEF, PCI could represent a safe and effective revascularization strategy achieving good midterm outcome and LVEF improvement.

Management of Chronic Total Coronary Occlusion in Stable Ischemic Heart Disease by Percutaneous Coronary Intervention Versus Coronary Artery Bypass Grafting Versus Medical Therapy

Coronary chronic total occlusions (CTOs) are found in approximately 20% of angiograms. We sought to assess the variation in the management of patients with CTOs and to compare the clinical outcomes of CTO lesions with those of non-CTO lesions. We conducted a population-based cohort study and included all patients with stable angina who underwent cardiac catheterization from October 1, 2012, to June 30, 2013, in Ontario, Canada. The primary outcome was a composite of mortality and hospitalization for myocardial infarction. A total of 7,864 patients were included, of whom 2,279 (29%) had a CTO. There were substantial differences in revascularization rates for patients with CTOs across hospitals in Ontario (44.9% to 94.1%). Revascularization was associated with improved outcomes in the overall cohort. Although the advantage of coronary artery bypass grafting over medical therapy was consistent in both patients with CTOs and patients without CTOs, the benefit of percutaneous coronary intervention (PCI) was limited to patients without CTOs (hazard ratio 0.56, 95% confidence interval 0.40- to 0.78), with no difference in patients with CTOs. The CTO lesion, however, was revascularized in few of the PCI cases (41.1%), with PCI limited to the non-CTO lesion in most patients.

Percutaneous coronary interventions of chronic total -occlusions; a review of clinical indications, treatment strategy and current practice

Chronic total occlusions (CTOs) are commonly encountered in patients undergoing coronary angiography, but percutaneous coronary intervention (PCI) for CTO is currently infrequently performed owing to the perception of limited clinical benefit, high complexity and cost of intervention, and perceived risk of complications. Numerous observational studies have demonstrated that successful CTO revascularization is associated with better cardiovascular outcomes and enhanced quality of life (QOL). However, in the absence of randomized trials, its prognostic benefit remains debated. Nevertheless, over the past decade the interest in CTO-PCI has exponentially grown due to important developments in dedicated equipment and techniques, resulting in high success and low complication rates. A number of factors must be taken into consideration in selecting patients for CTO-PCI, including presence of symptoms attributable to the CTO, extent of ischaemia distal to the occlusion, and degree of myocardial viability. In this review, we focus on the impact of CTO revascularization on clinical outcomes and QOL and on appropriate patient selection. Data regarding efficacy and safety of recent advances in PCI-CTO techniques will be discussed. Steps involved in setting up a dedicated CTO program will be outlined and the current CTO landscape in Belgium will be briefly highlighted. The overall aim of this review is to promote a more balanced approach to management of patients with a CTO.

Coronary intervention for chronic total occlusion: current indications and future directions

Chronic total occlusions (CTOs) are routinely encountered during coronary angiography, but subsequent revascularization rates are low. This has likely been driven by a historical belief that there is minimal clinical benefit and poor success rates with a percutaneous coronary intervention (PCI). However, in the current era, with the development of new techniques and tools, experienced operators can perform CTO-PCI successfully in the majority of patients. The current indications and benefit of CTO-PCI remain a topic of controversy and debate. There is a growing body of predominantly nonrandomized studies reporting both short-term and long-term outcomes of CTO-PCI. Recent and upcoming randomized-controlled trials in this area will also potentially expand indications in both stable and patients with acute coronary syndrome. In this review, we will discuss the current evidence for CTO-PCI and also future directions in this field.

Approach to CTO Intervention: Overview of Techniques

OPINION STATEMENT

Successful percutaneous coronary intervention (PCI) of chronic total occlusions (CTOs) has been associated with significant clinical benefits, but remains technically demanding. Failure to cross the CTO with a guidewire is the most common cause of CTO PCI failure. CTO crossing can be achieved in the antegrade or retrograde direction and can be accomplished by maintaining true lumen position throughout or via subintimal dissection/reentry techniques. A procedural plan should be created prior to the procedure through careful angiographic review of four key parameters: (a) morphology of the proximal occlusion cap; (b) length of the occlusion; (c) quality of the distal vessel and presence of bifurcation at the distal cap; and (d) suitability of collateral circulation for retrograde crossing. Dual coronary injection is recommended in all cases with contralateral collaterals for detailed characterization of the lesion. If one approach fails to progress, a quick transition to the next approach is encouraged to maximize efficacy and efficiency. Procedural complications, including vessel perforation, may occur more frequently in CTO as compared with non-CTO PCI; hence, availability of necessary equipment and expertise in treating such complications are essential.

Association of β-blocker therapy with long-term clinical outcomes in patients with coronary chronic total occlusion

There are limited data regarding the efficacy of β-blockers for secondary prevention in patients with coronary chronic total occlusion (CTO). Therefore, we investigated the association of β-blocker therapy with long-term clinical outcomes in CTO patients. From March 2003 to February 2012, a total of 2024 CTO patients treated with either medical therapy alone or revascularization were enrolled in the study. We assessed 1596 patients with stable ischemic heart disease and divided them into the β-blocker group (n = 932) and the no-β-blocker group (n = 664). The primary outcome was all-cause death. The median follow-up duration was 3.9 (interquartile range: 2.0-6.2) years. All-cause death occurred in 11.6% patients in the β-blocker group and 13.6% patients in the no-β-blocker group (hazard ratio [HR]: 0.81, 95% confidence interval [CI]: 0.61-1.08; P = 0.15). In the propensity score-matched population (570 pairs), all-cause death occurred in 12.3% patients in the β-blocker group and 12.8% patients in the no-β-blocker group (HR: 0.93, 95% CI: 0.67-1.29; P = 0.66). In subgroup analysis, β-blocker therapy was associated with better outcome, in terms of all-cause death, in patients with CTO of the left anterior descending coronary artery and Synergy Between PCI with Taxus and Cardiac Surgery (SYNTAX) score ≥23 (P for interaction = 0.01 and 0.02, respectively). In conclusion, β-blocker therapy was not associated with favorable long-term clinical outcomes in stable CTO patients, regardless of treatment strategy. However, β-blocker therapy might be beneficial in a highly selective group of CTO patients with a high ischemic burden.

The collateral circulation of coronary chronic total occlusions

AIMS

Despite advances in understanding the physiological role of collaterals in coronary chronic total occlusions (CTOs), collateral anatomy remains poorly defined. Our aim was to define the anatomy and interventional utility of collaterals within a large population of patients with CTOs.

METHODS AND RESULTS

We studied the coronary angiograms of 481 patients with 519 CTOs at six centres in the U.K. over four years. Detailed angiographic analysis was performed by interventional cardiologists specialising in CTO percutaneous coronary intervention (PCI). All visible collaterals with a collateral connection (CC) grade ≥1 were recorded. A subgroup of CTOs (n=277) was assessed for interventional capability, defined as whether the collateral supply was able to facilitate retrograde access. We described 45 different collateral patterns: 20 in right coronary artery (RCA), 13 in left anterior descending (LAD), and 12 in circumflex artery CTOs. Septal collaterals from the LAD to the right posterior descending artery (RPDA), and from the posterior descending artery to the LAD were most common, and most often considered as having "interventional capability".

CONCLUSIONS

This is the largest analysis of collateral circulation anatomy in a population of patients with CTOs. We anticipate that these data will be of significant benefit in angiographic analysis and procedure planning for CTO PCI.

Assessment of Inducible Myocardial Ischemia, Quality of Life, and Functional Status After Successful Percutaneous Revascularization in Patients With Chronic Total Coronary Occlusion

The benefits of chronic total coronary occlusion (CTO) revascularization are not well established. In this prospective cohort study, 47 consecutive patients with successful percutaneous recanalization of CTO underwent adenosine stress cardiac magnetic resonance (CMR), 6-minute walk test (6MWT), and the Short Form-36 Health Survey before and 6 months after the procedure. Successful recanalization of a CTO was followed by significant improvement of (1) global physical and mental health status; (2) the distance walked in the 6MWT; (3) the incidence of chest pain at the end of the 6MWT; and (4) the score of a novel CMR ischemic burden index on the basis of the characteristics of adenosine stress perfusion defects (extension, persistence, transmurality, and induced contractile regional dysfunction). Patients with greater CMR ischemic index before percutaneous revascularization showed better improvement in the 6MWT. In conclusion, successful recanalization of a CTO leads to a concurrent improvement in ischemic burden, exercise tolerance, angina frequency, and quality of life scores. Patients with a high ischemic CMR score before CTO recanalization showed the better improvement in exercise tolerance.

Theory and practical based approach to chronic total occlusions

Coronary chronic total occlusions (CTOs) represent the most technically challenging lesion subset that interventional cardiologists face. CTOs are identified in up to one third of patients referred for coronary angiography and remain seriously undertreated with percutaneous techniques. The complexity of these procedures and the suboptimal success rates over a long period of time, along with the perception that CTOs are lesions with limited scope for recanalization, account for the underutilization of CTO Percutaneous Coronary Intervention (PCI). During the last years, dedicated groups of experts in Japan, Europe and United States fostered the development and standardization of modern CTO recanalization techniques, achieving success rates far beyond 90%, while coping with lesions of increasing complexity. Numerous studies support the rationale of CTO revascularization following documentation of viability and ischemia in the territory distal to the CTO. Successful CTO PCI provide better tolerance in case of future acute coronary syndromes and can significantly improve angina and left ventricular function. Randomized trials are on the way to further explore the prognostic benefit of CTO revascularization. The following review reports on the theory and the most recent advances in the field of CTO recanalization, in an attempt to promote a more balanced approach in patients with chronically occluded coronary arteries.