Current perspectives on coronary chronic total occlusions: the Canadian Multicenter Chronic Total Occlusions Registry

Thirty-day and 5-year results of percutaneous coronary intervention for in-stent restenotic chronic total occlusion lesions: Data from 2,659 consecutive patients

OBJECTIVES

To investigate the procedure success rate and clinical outcomes of in-stent restenotic chronic total occlusion (ISR-CTO) percutaneous coronary intervention (PCI).

BACKGROUND

Few studies have reported the short- and long-term clinical outcomes of ISR-CTO PCI.

METHOD

Patients who underwent ISR-CTO (n = 212) or de-novo CTO (n = 2,447) PCI at Fuwai Hospital from 2010 to 2013 were enrolled. Thirty-day and 5-year clinical outcomes were analyzed. The primary outcome was the incidence of all-cause death, myocardial infarction (MI), and heart failure at follow-up. The secondary outcome was the recanalization result (reasonable, suboptimal, or failed recanalization).

RESULTS

ISR-CTO PCI had a higher rate of suboptimal recanalization than de-novo CTO PCI (p < .01). The syntax score before PCI (odds ratio (OR): 1.06; 95% confidence interval (CI): 1.02-1.10; p = .002) and occlusion length ≥ 20 mm (OR: 2.70:95% CI: 1.46-4.98; p = .001) were predictors of suboptimal recanalization in ISR-CTO PCI. Cardiac death (p = .03) and 30-day all-cause mortality (p = .05) were higher among patients who underwent ISR-CTO PCI. The ISR-CTO group had a higher rate of MI (p = .07) at 5 years. Suboptimal recanalization (hazard ratio: 2.56; 95% CI: 1.13-5.83; p = .025) was an independent predictor of long-term major adverse events in ISR-CTO.

CONCLUSIONS

Suboptimal recanalization, 30-day cardiac death, and long-term MI rates are higher for ISR-CTO PCI than de-novo CTO PCI. Suboptimal recanalization is an independent predictor of long-term major adverse events after ISR-CTO PCI.

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.

Long-Term Outcomes of Successful Recanalization Compared With Optimal Medical Therapy for Coronary Chronic Total Occlusions in Patients With and Without Left Ventricular Systolic Dysfunction

Background: The number of coronary chronic total occlusion (CTO) patients with left ventricular (LV) systolic dysfunction is significant, but the clinical outcomes of these patients are rarely reported. The present retrospective cohort study aimed to investigate the long-term outcomes of successful recanalization vs. optimal medical therapy (MT) for CTOs in patients with preserved and impaired LV systolic function.

Methods: A total of 1,895 patients with CTOs were stratified according to LV function. Of these, 1,420 patients (74.9%) with LV ejection fraction (LVEF) >45% and 475 patients (25.1%) with LVEF ≤45% were treated with optimal MT or successful CTO percutaneous coronary intervention (PCI). A 1:1 propensity score matching (PSM) was conducted to reduce the impact of potential confounding on the outcomes. The primary outcome was the frequency of major adverse cardiac events (MACEs).

Results: Throughout a 2.6-year follow-up and after adjusting for confounders, among patients with preserved LV function, successful CTO PCI was associated with reduced incidence of MACE (14.2 vs. 23.9%, adjusted HR 0.63, 95% CI 0.48–0.83, p = 0.001) compared to MT. There was no significant difference in MACE occurrence (29.6 vs. 28.9%, adjusted HR 1.05, 95% CI: 0.71–1.56, p = 0.792) between successful recanalization and MT in patients with LV systolic dysfunction. The primary outcome among patients with impaired and preserved LV systolic function after PSM was similar to that from earlier findings before PSM was conducted. A significant interaction between LV function and therapeutic strategy for MACE was observed (interaction p = 0.038).

Conclusions: Compared to MT alone for management of patients with CTOs, successful CTO PCI may reduce the risk of MACE in patients with preserved LV systolic function, but not in patients with LV dysfunction.

Reattempt Percutaneous Coronary Intervention of Chronic Total Occlusions after Prior Failures: A Single-Center Analysis of Strategies and Outcomes

OBJECTIVE

The initial recanalization rate of coronary chronic total occlusions (CTOs) is >85% when performed by experienced operators, but only 10% of prior failed CTO patients receive reattempted recanalization. This retrospective study analyzed the success rate and strategies used in reattempt percutaneous coronary intervention (PCI) of CTOs after prior failures.

METHODS

Overall, 206 patients with 212 CTOs were enrolled. All patients with prior recanalization failures received reattempt PCIs from January 2015 to March 2019 at Zhongshan Hospital, Fudan University. Data on clinical factors (age, sex, comorbidities, left ventricular ejection fraction, history of cigarette usage, and revascularization), angiographic characteristics of CTOs (target lesion, Japanese Chronic Total Occlusion (J-CTO) score, the morphology of CTO lesions, and collateral channel scale), strategies (procedural approach and use of devices), and major adverse events were obtained and analyzed.

RESULTS

The mean age of enrolled patients was 60.96 ± 12.36 years, with a male predominance of 90.3%. Of the patients, 47.1% had a prior myocardial infarction and 70.4% underwent stent implantation previously, while the in-stent occlusion rate was 6.6%. CTOs were primarily localized in the left anterior descending artery (43.9%) and the right coronary artery (43.9%). 80.7% of lesions were classified as very difficult (J-CTO score ≥3), and the overall success rate was 81.1%. In multivariable regression analysis, J-CTO score, collateral channel scale, application of coronary multispiral computed tomography angiography, dual injection, intravascular ultrasound, active greeting technique, parallel wiring, and CTO morphology were predictors of recanalization success. There were no significant differences in rates of procedural complications between the final recanalization success and failure groups.

CONCLUSIONS

Recanalization of complex CTOs is associated with high success rate and low complication rates when performed by high-volume CTO operators and after multiple reattempts.

Comparison of Clinical Outcomes Between Second-and First-Generation Drug-Eluting Stents in Patients With Chronic Total Occlusion Lesion: A Meta-Analysis

Background and Objectives: The second-generation drug-eluting stents have been used to treat chronic total occlusion lesion. However, there is limited evidence of the clinical outcomes that whether the second-generation drug-eluting stents is superior to first-generation ones in patients with chronic total occlusion lesion undergoing percutaneous coronary intervention. The study aimed to compare the differences in clinical outcomes between the two generations drug-eluting stents in patients with those by a meta-analysis.

Methods: PubMed, Embase, the Cochrane library and Web of science databases were systemically searched before March, 2021. Randomized controlled trials and observational studies were included to compare the second-generation drug-eluting stents with the first-generation ones in patients with chronic total occlusion lesion undergoing percutaneous coronary intervention. The clinical outcomes were major adverse cardiac events (MACE), target vessel revascularization, myocardial infarction, all-cause death. Fixed effects models were used to calculate the odds ratio (OR) and 95% confidence interval (CI) of each clinical outcome. Sensitivity analysis was performed to detect potential sources of heterogeneity. Subgroup analyses were used to assess the differential effects.

Results: The meta-analysis included eight studies involving 4,583 patients with chronic total occlusion lesion undergoing percutaneous coronary intervention. Pooled analysis showed that the incidence of MACE (OR = 0.68, 95%CI 0.54–0.85, P = 0.0008), target vessel revascularization (OR = 0.70, 95%CI 0.54–0.91, P = 0.007), and myocardial infarction (OR = 0.58, 95%CI 0.37–0.93, P = 0.02) were lower in the second-generation drug-eluting stents compared with the first-generation ones. However, there was not difference in all-cause deaths between two drug-eluting stents (OR = 0.67, 95%CI 0.45–1.01, P = 0.05).

Conclusions: The second-generation drug-eluting stents are associated with lower MACE, target vessel revascularization, and myocardial infarction compared with the first-generation ones in patients with chronic total occlusion lesion undergoing percutaneous coronary intervention. The results of this study can provide a reference for the selection of stents in patients with chronic total occlusion lesion. Further randomized controlled trials are needed to verify that the second-generation drug-eluting stents is superior to the first-generation ones in patients with chronic total occlusion (Registered by PROSPERO, CRD42020158406).

Original Article--Value of Pathological Q Waves and Angiographic Collateral Grade in Patients Undergoing Coronary Chronic Total Occlusion Recanalization: Cardiac Magnetic Resonance Study

Background/aim

Successful coronary chronic total occlusion (CTO) revascularization was found by many studies to be associated with improved left ventricular (LV) systolic function and survival if evidence of viability is present. Little is known about the association of CTO revascularization in patients with electrocardiographic Q waves and improvement in angina burden as a measurement of health-related quality of life (HRQOL) afterwards.

Methods

In this study, 100 patients with single vessel CTO were included. Myocardial viability was tested by late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) and 50 patients showed evidence of viability. Seattle Angina Questionnaire (SAQ) scores were used as a measure of HRQOL.

Results

Pathological Q waves were present in 48 patients (including 19 patients with viable CTO territory) out of 100 patients. Patients with Q waves tended to have worse Seattle Angina Questionnaire (SAQ) scores compared to those with no Q waves (31.2 ± 11.7 vs 45.3 ± 13.9 respectively, p = 0.002), worse LV systolic function and wall motion score index (WMSI) on CMR. They also had significantly less prevalence of viability (p < 0.001). Patients with Q waves and positive viability had lower SAQ scores (37.2 ± 10.1 vs 52.7 ± 13.2 respectively, p = 0.02), higher LVEF and lower WMSI. They also had well developed collateral grade (2.1 ± 1.03 vs 0.7 ± 0.82 respectively, p < 0.001). After successful percutaneous coronary intervention (PCI), in the viable LV group, presence of Q waves was not associated with better LV functional recovery, while those with higher collateral grades were more likely to have better LV functional recovery post CTO-PCI. Patients with Q waves and viable CTO territory showed significantly better SAQ scores compared to pre-PCI (87.3 ± 12.2 vs 37.2 ± 10.1 respectively, p < 0.001). For angina frequency, post–PCI score was 80.2 ± 7.9 compared to 39.2 ± 7.1 before PCI, p < 0.001). Multivariate regression analysis showed that pathological Q waves, Rentrop's collateral grade and the Canadian Cardiovascular Society (CCS) angina class before PCI were the most significant independent predictors of improved HRQOL as reflected by SAQ (OR for Q waves 7.83, 95% CI 1.62–18.91,p 0.003), (OR for Rentrop's collateral grade 8.31,95% CI 2.21–26.33, p < 0.001), (OR for CCS class 8.39, 95% CI 1.21–20.8, p 0.01).

Conclusion

Well-developed collateral circulation could independently predict LV functional recovery after CTO-PCI. Patients with Q waves and viable CTO territory tend to have higher CCS class before revascularization and get significant improvement of HRQOL after PCI. Other predictors of improved HRQOL are Rentrop's collateral grade and worse CCS class before PCI.

Advances in the Post-coronary Artery Bypass Graft Management of Occlusive Coronary Artery Disease

Revascularisation of chronic total occlusion (CTO) represents one of the most challenging aspects of percutaneous coronary intervention, but advances in equipment and an understanding of CTO revascularisation techniques have resulted in considerable improvements in success rates. In patients with prior coronary artery bypass grafting (CABG) surgery, additional challenges are encountered. This article specifically explores these challenges, as well as antegrade methods of CTO crossing. Techniques, equipment that can be used and reference texts are highlighted with the aim of providing potential CTO operators adequate information to tackle additional complexities likely to be encountered in this cohort of patients. This review forms part of a wider series where additional aspects of patients with prior CABG should be factored into decisions and methods of revascularisation.

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.

Clinical Outcomes in Chronic Total Occlusion Revascularization Versus No Chronic Total Occlusion Revascularization: Variability by Target Vessel

We aimed to investigate the impact of target vessel on clinical outcomes in chronic total occlusion (CTO) revascularization versus no CTO revascularization. This multicenter, retrospective, cohort study involves patients with ≥1 CTO. After classification based on different CTO target vessels or multiple CTOs, patients were further categorized as the CTO revascularization group and the no CTO revascularization group based on treatment received. The primary outcome was a composite of death, myocardial infarction, stroke, repeated revascularization, and hospital admission due to ischemic symptoms. From August 2016 to August 2017, 1712 eligible patients were consecutively enrolled. Chronic total occlusion revascularization was associated with lower risk of 1-year major adverse cardiovascular and cerebrovascular events (MACCEs; adjusted hazard ratio [HR]: 0.36; 95% CI: 0.20-0.67; P = .001) compared with no CTO revascularization in left anterior descending (LAD) CTO patients. The benefit of CTO revascularization was not evident among those with left circumflex (LCX; adjusted HR: 0.51; 95% CI: 0.23-1.10; P = .087), right coronary artery (RCA; adjusted HR: 1.17; 95% CI: 0.59-2.33; P = .648), and multiple CTOs (adjusted HR: 1.00; 95% CI: 0.41-2.44; P = .994). Revascularization for LAD CTO, but not LCX, RCA, or multiple CTOs, was associated with lower risk of 1-year MACCEs compared with no CTO revascularization.

Long-Term Outcomes of Percutaneous Coronary Intervention for Patients With In-Stent Chronic Total Occlusion Versus De Novo Chronic Total Occlusion

Limited data are available on long-term outcomes and health status in the treatment of in-stent coronary chronic total occlusion (IS-CTO) and de novo coronary chronic total occlusion (de novo CTO). This study compared the long-term clinical outcomes and health status of percutaneous coronary intervention (PCI) for patients with IS-CTO versus patients with de novo CTO in the drug-eluting stent era. We screened 483 consecutive patients with 1 CTO lesion, including 81 patients with IS-CTO and 402 patients with de novo CTO. Propensity score matching was used to balance baseline characteristics between the 2 groups. The clinical end point was major adverse cardiac events (MACE). The success rates of CTO lesion revascularization were similar in both groups. In the propensity score-matched patients, after a median follow-up of 36 months, MACE was observed in 32.8% of patients with IS-CTO versus 13.5% of the patients with de novo CTO (P < .001), mainly driven by target-vessel revascularization (21.9% vs 6.7%; P < .01). Moreover, patients with IS-CTO had significantly worse Seattle Angina Questionnaire anginal stability scores than the patients with de novo CTO. In conclusion, patients with IS-CTO after PCI had a worse clinical outcome, mainly MACE, and a poorer anginal stability in the long term than patients with de novo CTO.

Coronary Sinus Reducer for the Treatment of Chronic Refractory Angina: Will This Challenge the Treatment of Coronary Chronic Total Occlusions?

PURPOSE OF REVIEW

The prevalence of angina despite optimal medical therapy is high among patients with coronary chronic total occlusions. Despite advancements in techniques and operator's experience, percutaneous revascularization of coronary chronic total occlusions is still associated with a not negligible risk of failures and complications. The Coronary Sinus Reducer, a new device developed to improve angina, has shown promising results in terms of efficacy and safety in patients with refractory symptoms. The aim of this review is to summarize the evidence so far available and to guide clinicians in the selection of patients with chronic total occlusions that could benefit more from Coronary Sinus Reducer implantation.

RECENT FINDINGS

A recently published study suggests a clear value of this device in patients with chronic total occlusions. This is likely to be related to the presence of a well-developed collateral circulation. A careful evaluation of risks and benefits of both myocardial revascularization and Coronary Sinus Reducer implantation should be done in all the cases in order to better define the optimal strategy for the patient. The Coronary Sinus Reducer implantation has a rationale in patients with chronic total occlusion as an alternative or additional therapy to myocardial revascularization.

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.

Chronic total occlusion percutaneous coronary intervention in octogenarians and nonagenarians

OBJECTIVE

The outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) in octogenarians and nonagenarians have received limited study.

METHODS

We compared in-hospital outcomes of CTO PCI between patients ≥80 vs. <80-years-old in 6233 CTO PCIs performed between 2012 and 2020 at 33 U.S. and international centers.

RESULTS

There were 415 octogenarians and nonagenarians in our study (7% of the total population). Compared with younger patients, octo- and nonagenarians were less likely to be men (73% vs. 83.2%, p < 0.0001) and more likely to have atrial fibrillation (27% vs. 12%, p < 0.0001) and prior coronary artery bypass graft surgery (CABG) (43% vs. 29%, p < 0.0001). They were more likely to have CTOs with moderate/severe calcification (71% vs. 46%, p < 0.0001), but had similar mean J-CTO scores (2.5 ± 1.3 vs. 2.4 ± 1.3, p = 0.08). They had lower technical and procedural success (82.2% vs. 86.3%, p = 0.0201; 80.3% vs. 84.8%, p = 0.016, respectively) and higher incidence of in-hospital major adverse cardiovascular events (3.4% vs. 1.8%, p = 0.021). On multivariable analysis PCI in octo- and nonagenarians was not independently associated with technical and procedural success or with in-hospital MACE.

CONCLUSION

CTO PCI is feasible in octo- and nonagenarians, although success rates are lower, and the risk of complications is higher compared with younger patients, likely related to more comorbidities and higher coronary lesion complexity.

Identification of micro-channels within chronic total occlusions using contrast-enhanced ultrasound

BACKGROUND

Vascular micro-channels within chronic total occlusions (CTO) have been identified in histopathology and animal studies. They have been proposed as a potential path for achieving endovascular crossing via the lumen. There are currently no noninvasive means of imaging these structures. The aim of this study was to investigate whether contrast-enhanced ultrasound (CEUS) examination can identify micro-channels within CTO in humans.

METHODS

CTO within the femoropopliteal arteries were imaged with CEUS examination in 38 patients. Segments containing micro-channels were identified and their length measured. The proportion of occlusion length containing micro-channels was assessed for each case. Micro-channel appearances including linear or tortuous configuration, crossing of occlusion caps, and connections to vasa vasorum were recorded.

RESULTS

The median CTO length was 17.0 cm (interquartile range [IQR], 6.9-27.9 cm) and median age of CTO was 12 months (IQR, 6-16 months). Micro-channels were identified in 92.1% of cases (35/38). The median length within a lesion containing micro-channels was 6.4 cm (IQR, 2.4-14.3 cm) and median proportion of CTO containing micro-channels was 47.9% (IQR, 1.7%-28.5%). A linear micro-channel configuration was seen in 84.2% of cases and a tortuous configuration was seen in 57.9% of cases. Micro-channel connections through the cap were seen in 50% (19/38 cases) and connections to the vasa vasorum in 71.1% (27/38 cases). No association was found between the proportion of each lesion containing micro-channels and CTO age, lesion length or calcification severity. There were no adverse effects related to contrast use.

CONCLUSIONS

CEUS can be used to detect micro-channels in CTO in human femoropopliteal arteries. This imaging technique is safe and minimally invasive and may represent a practical method for selection of occlusion crossing method. Further work is required to determine whether identification of micro-channels can be used to improve treatment decision-making and provide a better understanding of the natural history of femoropopliteal CTO.

Long-term prognosis of chronic total occlusion treated by successful percutaneous coronary intervention in patients with or without diabetes mellitus: a systematic review and meta-analysis

Background

Diabetes mellitus (DM) is highly prevalent among patients undergoing percutaneous coronary intervention (PCI) for chronic total occlusion (CTO). Therefore, the purpose of our study was to investigate the clinical outcomes of CTO-PCI in patients with or without DM.

Methods

All relevant articles published in electronic databases (PubMed, Embase, and the Cochrane Library) from inception to August 7, 2020 were identified with a comprehensive literature search. Additionally, we defined major adverse cardiac events (MACEs) as the primary endpoint and used risk ratios (RRs) with 95% confidence intervals (CIs) to express the pooled effects in this meta-analysis.

Results

Eleven studies consisting of 4238 DM patients and 5609 non-DM patients were included in our meta-analysis. For DM patients, successful CTO-PCI was associated with a significantly lower risk of MACEs (RR = 0.67, 95% CI 0.55–0.82, p = 0.0001), all-cause death (RR = 0.46, 95% CI 0.38–0.56, p < 0.00001), and cardiac death (RR = 0.35, 95% CI 0.26–0.48, p < 0.00001) than CTO-medical treatment (MT) alone; however, this does not apply to non-DM patients. Subsequently, the subgroup analysis also obtained consistent conclusions. In addition, our study also revealed that non-DM patients may suffer less risk from MACEs (RR = 1.26, 95% CI 1.02–1.56, p = 0.03) than DM patients after successful CTO-PCI, especially in the subgroup with a follow-up period of less than 3 years (RR = 1.43, 95% CI 1.22–1.67, p < 0.0001).

Conclusions

Compared with CTO-MT alone, successful CTO-PCI was found to be related to a better long-term prognosis in DM patients but not in non-DM patients. However, compared with non-DM patients, the risk of MACEs may be higher in DM patients after successful CTO-PCI in the drug-eluting stent era, especially during a follow-up period shorter than 3 years.

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.

Prognostic Impact of Percutaneous Coronary Intervention of Chronic Total Occlusion in Acute and Periprocedural Myocardial Infarction

Coronary chronic total occlusion (CTO) has gained increasing clinical attention as the most advanced form of coronary artery disease. Prior studies already indicated a clear association of CTO with adverse clinical outcomes, especially in patients with acute myocardial infarction (AMI) and concomitant CTO of the non-infarct-related coronary artery (non-IRA). Nevertheless, the prognostic impact of percutaneous coronary intervention (PCI) of CTO in the acute setting during AMI is still controversial. Due to the complexity of the CTO lesion, CTO-PCI leads to an increased risk of complications compared to non-occlusive coronary lesions. Therefore, this review outlines the prognostic impact of CTO-PCI in patients with AMI. In addition, the prognostic impact of periprocedural myocardial infarction caused by CTO-PCI will be discussed.

Endovascular myocardial revascularization in patients with multivessel coronary artery disease with chronic total occlusion and high surgical risk

The main reason  for incomplete myocardial revascularization is the presence of chronic coronary total occlusion (CTO), which is detected in every fourth patient during coronary angiography. At the same time, a generally accepted approach  to the treatment of CTO has not yet been developed.

Aim. To assess the rationale of complete myocardial revascularization in patients with multivessel coronary artery disease  (CAD) with chronic total occlusion and high surgical risk.

Material and methods. This retrospective,  open-label,  non-randomized clinical trial was carried out included 180 patients multivessel CAD and CTO. The patients  underwent endovascular  surgery for complete myocardial revascularization. Depending on the success of surgery, the patients were divided into groups of complete and incomplete myocardial revascularization. Endpoints were death, acute coronary syndrome, re-revascularization after 1-year follow-up. Left ventricular (LV) contractility and clinical status  of patients  in the study groups after 1 year of observation was assessed.

Results. The median follow-up was 12,1 months. The successful  rate of revascularization was 79,4%. The incidence of main composite endpoint in the group of complete myocardial revascularization was 5,59%, while in the group of incomplete revascularizations — 21,6% (p=0,005).

Conclusion. The study showed  that low incidence  of intraoperative complications and a high successful  rate of revascularization are characteristic of complete myocardial revascularization in patients at high surgical risk with multivessel CAD and CTO. Complete myocardial revascularization leads to a significant decrease in the incidence of major coronary events.

Outcomes of percutaneous coronary intervention for chronic total occlusions in the elderly: A systematic review and meta-analysis

Objective

This study aimed to compare outcomes of percutaneous coronary intervention (PCI) for chronic total occlusions (CTO) in the elderly (≥75 years) versus nonelderly and assess the impact of successful CTO‐PCI in the elderly.

Methods

PubMed, Embase, ScienceDirect, CENTRAL, and Google Scholar databases were searched up to October 1, 2020. Mortality rates and major adverse cardiac events (MACE) were compared between elderly and nonelderly patients and successful versus failed CTO‐PCI in the elderly.

Results

Eight studies were included. Meta‐analysis indicated no statistically significant difference in the risk of in‐hospital mortality (RR: 1.97 95% CI: 0.78, 4.96 I² = 0% p = .15) but higher tendency of in‐hospital MACE (RR: 2.30 95% CI: 0.99, 5.35 I² = 49% p = .05) in the elderly group. Risk of long‐term mortality (RR: 3.79 95% CI: 2.84, 5.04 I² = 41% p < .00001) and long‐term MACE (RR: 1.53 95% CI: 1.14, 2.04 I² = 80% p = .004) were significantly increased in the elderly versus nonelderly. Elderly patients had a significantly reduced odds of successful PCI as compared to nonelderly patients (OR: 0.63 95% CI: 0.54, 0.73 I² = 1% p < .00001). Successful CTO‐PCI was associated with reduction in long‐term mortality (HR: 0.51 95% CI: 0.34, 0.77 I² = 27% p = .001) and MACE (HR: 0.60 95% CI: 0.37, 0.97 I² = 53% p = .04) as compared to failed PCI in elderly.

Conclusions

Elderly patients may have a tendency of higher in‐hospital MACE with significantly increased long‐term mortality and MACE after CTO‐PCI. The success of PCI is significantly lower in the elderly. In elderly patients with successful PCI, the risk of long‐term mortality and MACE is significantly reduced.

Management of Chronic Total Occlusion of Coronary Artery

Chronic total occlusion (CTO) of a coronary artery is typically defined as a completely occluded artery without any antegrade flow and a duration of at least 3 months. We reviewed the current literature describing the optimal management of CTO including the role of revascularization and choice of modality, i.e., percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery. Databases (PubMed, the Cochrane Library, Embase, EBSCO, Web of Science, and CINAHL) were searched and relevant studies of patients with CTO were selected for review. The prevalence of coronary artery CTOs is approximately 25% among patients undergoing coronary angiography for angina. Available data suggests that PCI of CTO can be a technically complex procedure with relatively lower success rates compared with non-CTO PCI and typically associated with a higher complication rate especially at nonspecialized centers. Furthermore, successful CTO-PCI is associated with symptomatic improvement but does not appear to improve mortality, myocardial infarction, stroke, and repeat revascularization rates. Based on contemporary data, PCI of CTO lesions may be considered in patients with incapacitating angina despite treatment with optimal guideline-directed medical therapy and in whom based on coronary anatomy there is a reasonable chance of technical success with an acceptable risk.

Incidence and outcomes of chronic total occlusion percutaneous coronary intervention in the Netherlands: data from a nationwide registry

Background

Patients with chronic total coronary occlusions (CTO) are at increased risk for poor clinical outcomes. We aimed to determine the incidence of CTO percutaneous coronary intervention (PCI) and to identify CTO patients at risk for cardiac events in the nationwide Netherlands Heart Registration (NHR).

Methods

We included all PCI procedures with ≥1 CTO registered in the NHR from January 2015 to December 2018, excluding acute interventions. We used multivariable logistic regression of baseline characteristics to calculate the risk for events as odds ratios (OR) with 95% confidence intervals (CI).

Results

Of the PCIs performed during the study period, 6.3% (8,343/133,042) were for CTOs, with the percentage increasing significantly over time from 5.9% in 2015 to 6.6% in 2018 (p < 0.001). Coronary artery bypass grafting <24 h was carried out in 0.3%, and the only significant predictor was diabetes mellitus (OR 2.97, 95% CI 1.04–8.49, p = 0.042). Myocardial infarction (MI) <30 days occurred in 0.5%, and renal insufficiency (i.e. estimated glomerular filtration rate <30 ml/min per 1.73 m²) was identified as an independent predictor (OR 4.70, 95% CI 1.07–20.61, p = 0.040). Among patients undergoing CTO-PCI, 1‑year mortality was 3.7%, and independent predictors included renal insufficiency (OR 5.59, 95% CI 3.25–9.59, p < 0.001), left ventricular ejection fraction <30% (OR 3.43, 95% CI 2.00–5.90, p < 0.001), previous MI (OR 1.62, 95% CI 1.14–2.31, p = 0.007) and age (OR 1.06 per year increment, 95% CI 1.04–1.07, p < 0.001). Target-vessel revascularisation <1 year occurred in 11.3%.

Conclusion

CTO-PCI is still infrequently performed in the Netherlands. The most important predictor of mortality after CTO-PCI was renal insufficiency. Identification of patients at risk may help improve the prognosis of CTO patients in the future.

Electronic supplementary material

The online version of this article (10.1007/s12471-020-01521-y) contains supplementary material, which is available to authorized users.

Medical therapy vs early revascularization in diabetics with chronic total occlusions: A meta-analysis and systematic review

BACKGROUND

Management of chronic total occlusions (CTO) in diabetics is challenging, with a recent trend towards early revascularization [ER: Percutaneous coronary intervention (PCI) and bypass grafting] instead of optimal medical therapy (OMT). We hypothesize that ER improves morbidity and mortality outcomes in diabetic patients with CTOs as compared to OMT.

AIM

To determine the long term clinical outcomes and to compare morbidity and mortality between OMT and ER in diabetic patients with CTOs.

METHODS

Potentially relevant published clinical trials were identified in Medline, Embase, chemical abstracts and Biosis (from start of the databases till date) and pooled hazard ratios (HR) computed using a random effects model, with significant P value < 0.05. Primary outcome of interest was all-cause death. Secondary outcomes included cardiac death, prompt revascularization (ER) or repeat myocardial infarction (MI). Due to scarcity of data, both Randomized control trials and observational studies were included. 4 eligible articles, containing 2248 patients were identified (1252 in OMT and 1196 in ER). Mean follow-up was 45-60 mo.

RESULTS

OMT was associated with a higher all-cause mortality [HR: 1.70, 95% confidence interval (CI): 0.80-3.26, P = 0.11] and cardiac mortality (HR: 1.68, 95%CI: 0.96-2.96, P = 0.07). Results were close to significance. The risk of repeat MI was almost the same in both groups (HR: 0.97, 95%CI: 0.61-1.54, P = 0.90). Similarly, patients assigned to OMT had a higher risk of repeat revascularization (HR: 1.62, 95%CI: 1.36-1.94, P < 0.00001). Sub-group analysis of OMT vs PCI demonstrated higher all-cause (HR: 1.98, 95%CI: 1.36-2.87, P = 0.0003) and cardiac mortality (HR: 1.87, 95%CI: 0.96-3.62, P = 0.06) in the OMT group. The risk of repeat MI was low in the OMT group vs PCI (HR: 0.53, 95%CI: 0.31-0.91, P = 0.02). Data on repeat revascularization revealed no difference between the two (HR: 1.00, 95%CI: 0.52-1.93, P = 1.00).

CONCLUSION

In diabetic patients with CTO, there was a trend for improved outcomes with ER regarding all-cause and cardiac death as compared to OMT. These findings were reinforced with statistical significance on subgroup analysis of OMT vs PCI.

Association of Acute Procedural Results With Long-Term Outcomes After CTO PCI

OBJECTIVES

The aim of this study was to determine the association of procedural outcomes with long-term mortality and myocardial infarction (MI) after chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

BACKGROUND

The association between acute procedural results and subsequent outcomes has received limited study.

METHODS

Between January 2010 and December 2013, a total of 2,659 CTO PCI patients were consecutively enrolled. Procedural results were categorized into 3 groups: 1) optimal recanalization, with reperfusion of the occluded vessel and side branches (if any) with TIMI (Thrombolysis In Myocardial Infarction) flow grade 3; 2) suboptimal recanalization, meeting any of the following criteria: persistence of significant side branch occlusion, final TIMI flow grade 1 or 2, or residual percentage diameter stenosis >30%; and 3) procedural failure (i.e., failure to cross a lesion with a balloon angioplasty catheter). The primary outcome was the 5-year composite endpoint of cardiac death and MI.

RESULTS

Overall, optimal recanalization was achieved in 1,562 patients (58.7%), suboptimal recanalization was achieved in 399 patients (15.0%), and recanalization failed in 698 patients (26.3%). The 5-year incidence of the primary outcome was significantly higher in the suboptimal recanalization group compared with the optimal recanalization and the failure groups (10.1% vs. 6.5% vs. 6.3%; p = 0.046), which was driven mainly by higher risk for MI. In subgroup analysis, significant side branch occlusion was associated with numerically higher risk for 5-year MI (hazard ratio: 1.55; 95% confidence interval: 0.99 to 2.43; p = 0.054).

CONCLUSIONS

In this large cohort of CTO PCI patients, suboptimal recanalization was associated with significantly higher long-term incidence of cardiac death and MI compared with optimal recanalization or procedural failure.

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.

Prognostic impact of coronary chronic total occlusion on recurrences of ventricular tachyarrhythmias and ICD therapies

BACKGROUND

Despite a few studies evaluating the prognostic impact of coronary chronic total occlusion (CTO) in implantable cardioverter defibrillator (ICD) recipients, the impact of CTO on different types of recurrences of ventricular tachyarrhythmias, as well as their predictors has not yet been investigated in CTO patients.

METHODS

A large retrospective registry was used including all consecutive patients with ventricular tachyarrhythmias undergoing coronary angiography at index from 2002 to 2016. Only ICD recipients with CTO were compared to patients without (non-CTO). Kaplan-Meier and Cox regression analyses were applied for the primary end point of first recurrence of ventricular tachyarrhythmias at 5 years. Secondary end points comprised of the different types of recurrences, first appropriate ICD therapy and all-cause mortality at 5 years.

RESULTS

From a total of 422 consecutive ICD recipients with ventricular tachyarrhythmias at index, at least one CTO was present in 25%. CTO was associated with the primary end point of first recurrence of ventricular tachyarrhythmias at 5 years (55% vs. 39%; log rank p = 0.001; HR = 1.665; 95% CI 1.221-2.271; p = 0.001), as well as increased risk of first appropriate ICD therapy (40% vs. 31%; log rank p = 0.039; HR = 1.454; 95% CI 1.016-2.079; p = 0.041) and all-cause mortality at 5 years (26% vs. 16%; log rank p = 0.011; HR = 1.797; 95% CI 1.133-2.850; p = 0.013). Less developed collaterals (i.e., either ipsi- or contralateral compared to bilateral) and a J-CTO score ≥ 3 were strongest predictors of recurrences in CTO patients at 5 years.

CONCLUSION

A coronary CTO even in the presence of less developed collaterals and more complex CTO category is associated with increasing risk of recurrent ventricular tachyarrhythmias at 5 years in consecutive ICD recipients.

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.

Procedures for chronic total occlusion: when are they recommended and when not

Coronary chronic total occlusion (CTO) produces an important clinical problem, often treated with medical therapy or coronary artery bypass grafting. Recent clinical studies, both registries and randomized trials, demonstrated that percutaneous coronary interventions (PCI), could provide a valid therapeutic option. Nonetheless, significant reduction in all-cause mortality, cardiac mortality, myocardial infarction, MACE, and MACCE has not been demonstrated in the subgroups analysis of randomized trials. These analyses suggest that PCI for CTO should be reserved for patients with angina or with large areas of the myocardium with reversible ischaemia. Large randomized studies should search for a personalized approach, considering the risks and complexity of PCI in CTO, which should mainly consider the extension of the ischaemia and the viability of the myocardium.

Safety of Percutaneous Coronary Intervention for Chronic Total Occlusion in Patients With Multi-Vesel Disease: Sub-Analysis of the Japanese Retrograde Summit Registry

BACKGROUND

The success rate of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) has gradually increased thanks to the continuous development of devices and techniques. However, the impact of multi-vessel disease (MVD) on its success rate and safety is not well known.

METHODS

The clinical records of 5009 patients enrolled in the Japanese Retrograde Summit Registry and who had undergone PCI for CTO at 65 centers between 2012 and 2015 were reviewed. We compared the outcome for patients with and without MVD.

RESULTS

Two thousand nine hundred and seventy-eight patients (59%) had MVD. Although there was no significant difference in the J-CTO score between the two groups [MVD group 1.51 ± 1.07 vs. SVD group 1.48 ± 1.07, p = 0.48], the procedural success rate of CTO-PCI in the MVD group was significantly lower than that in the SVD group (87.2% vs. 90.2%, p = 0.001). However, occurrence of procedure-related adverse events (4% vs. 5%, p = 0.11), total fluoroscopy (70 ± 45 min vs. 69 ± 50 min, p = 0.75) and procedural time (154 ± 86 min vs. 151 ± 89 min, p = 0.36), and total amount of contrast media (219 ± 102 mL vs. 222 ± 105 mL, p = 0.33) did not differ between the two groups.

CONCLUSIONS

Although MVD had an impact on the success rate of CTO-PCI, it did not affect procedure-related adverse events.

Prognostic impact of collaterals in patients with a coronary chronic total occlusion: A meta-analysis of over 3,000 patients

OBJECTIVES

To assess the prognostic implications of the degree of coronary collaterals on outcomes in patients with a CTO.

BACKGROUND

Coronary chronic total occlusions (CTO) are identified frequently in patients undergoing coronary angiography and have been associated with poorer prognosis. Whether the degree of coronary collaterals, the hallmark of CTOs impacts prognosis, is unknown.

METHODS

A search of EMBASE, MEDLINE, and Cochrane Library was conducted to identify studies reporting on coronary collaterals and risk of all-cause mortality, acute myocardial infarction (AMI) and successful percutaneous coronary intervention (PCI). Patients with Rentrop grade 0 or 1 collaterals were defined as poor collaterals, while Rentrop grade 2 or 3 were defined as robust collaterals.

RESULTS

Twelve studies with a total of 3,369 were included. Patients with robust collaterals did not have lower rates of AMI (OR: 0.89, 95%CI: 0.39-2.04) or lower rates of all-cause mortality (OR: 0.81, 95% CI: 0.42-1.58), however were more likely to have successful PCI (OR: 4.04, 95%CI: 1.10-14.85).

CONCLUSION

The presence of robust collaterals is not associated with lower rates of AMI or mortality, but does increase the likelihood of successful CTO PCI. These results have importance implications with respect to the indications for CTO PCI as well as selecting appropriate patients to undergo the procedure.

Percutaneous coronary intervention versus medical therapy for chronic total coronary occlusions: a systematic review and meta-analysis of randomised trials

BACKGROUND

The results of chronic total occlusion percutaneous coronary intervention (CTO-PCI) trials are inconclusive. Therefore, we studied whether CTO-PCI leads to improvement of clinical endpoints and patient symptoms when combining all available randomised data.

METHODS AND RESULTS

This meta-analysis was registered in PROSPERO prior to starting. We performed a literature search and identified all randomised trials comparing CTO-PCI to optimal medical therapy alone (OMT). A total of five trials were included, comprising 1790 CTO patients, of whom 964 were randomised to PCI and 826 to OMT. The all-cause mortality was comparable between groups at 1‑year [risk ratio (RR) 1.70, 95% confidence interval (CI) 0.50-5.80, p = 0.40] and at 4‑year follow-up (RR 1.14, 95% CI 0.38-3.40, p = 0.81). There was no difference in the incidence of major adverse cardiac events (MACE) between groups at 1 year (RR 0.69, 95% CI 0.36-1.33, p = 0.27) and at 4 years (RR 0.85, 95% CI 0.60-1.22, p = 0.38). Left ventricular function and volumes at follow-up were comparable between groups. However, the PCI group had fewer target lesion revascularisations (RR 0.28, 95% CI 0.15-0.52, p < 0.001) and was more frequently free of angina at 1‑year follow-up (RR 0.65, 95% CI 0.50-0.84, p = 0.001), although the scores on the subscales of the Seattle Angina Questionnaire were comparable.

CONCLUSION

In conclusion, in this meta-analysis of 1790 CTO patients, CTO-PCI did not lead to an improvement in survival or in MACE as reported at long-term follow-up of up to 4 years, or to improvement of left ventricular function. However, CTO-PCI resulted in less angina and fewer target lesion revascularisations compared to OMT.

Incidence, Predictors, and Strategies for Failure of Retrograde Microcatheter Tracking After Successful Wiring of Septal Collateral Channels in Chronic Total Occlusions

Background

Retrograde microcatheter collateral channel (CC) tracking after successful wiring of septal CC is crucial for retrograde revascularization of coronary chronic total occlusion (CTO). However, the incidence, predictors, and strategies for failure of retrograde microcatheter CC tracking after successful wiring of septal CC remain unclear.

Methods

In total, 298 patients with CTO who underwent retrograde septal CC PCI between January 2015 and May 2019 were retrospectively analyzed. Clinical data were compared to investigate the predictors of initial microcatheter tracking failure.

Results

The initial and final microcatheter tracking success rates were 79.2% (236/298) and 96.6% (288/298), respectively. The procedural success rate was 94.0% (280/298). The right coronary artery-to-left anterior descending artery septal ratio (48.4% vs 33.1%, p=0.037) and CC tortuosity (34.6% vs 20.8%, p=0.045) were significantly higher in the initial microcatheter CC tracking failure group than in the successful tracking group. Multivariate logistic regression analysis revealed that severe collateral tortuosity (odds ratio [OR]: 13.241, 95% confidence interval [CI]: 3.429–27.057, p=0.038), CC entry angle of <90° (OR:4.921, 95% CI: 1.128–9.997, p=0.002), CC exit angle of <90° (OR:5.037, 95% CI: 2.237–11.182, p=0.004), use of Finecross MG as initial microcatheter (OR:1.826, 95% CI: 1.127–3.067, p=0.035), and shunning initial retrograde application of Guidezilla (OR:0.321, 95% CI: 0.267–0.915, p=0.024) were variables independently associated with initial microcatheter CC tracking failure in patients with CTO undergoing retrograde septal CC PCI.

Conclusion

The overall initial microcatheter CC tracking failure was 20.8%. Severecollateral tortuosity, CC entry, and exit angle of <90°, use of Finecross MG as initial microcatheter, and shunning initial retrograde application of Guidezilla were variables independently associated with initial microcatheter CC tracking failure in patients with CTO undergoing retrograde septal PCI.

Relationship between quality of coronary collateral and myocardial viability in chronic total occlusion: a magnetic resonance study

Revascularization of chronic total occlusion (CTO) is still debated regarding its indications and therapeutic benefits. Guidelines recommend patient selection based on ischemia detection and viability assessment. We aimed to investigate the relationship between the quality of coronary collaterals (CC), graded by Rentrop classification, and myocardial viability assessed by cardiovascular magnetic resonance (CMR). Unselected 100 consecutive patients with a single CTO were prospectively enrolled. CC of Rentrop grade two or three were considered as well-developed. Analyzing late gadolinium enhancement (LGE) images, CTO territories with mean segmental transmural scar extent < 50% were considered viable. Of the 100 patients (70 male, mean age 58.0 ± 6 years), 73 patients (73%) had angiographically visible CC. Based on LGE, patients were classified into viable (n = 50) and non-viable (n = 50) groups. Significant differences between both groups existed regarding frequency of diabetes mellitus (p = 0.044), frequency of congestive heart failure (p = 0.032), presence of pathological Q in CTO territory (p = 0.039); and presence of well-developed CC (p < 0.001). Binary logistic regression and receiver operating characteristic curve showed that presence of well-developed CC could independently (OR 9.4, 95% CI: 2.6-33.6, p < 0.001) predict myocardial viability with a sensitivity and a specificity of 72% and 74%, respectively (AUC: 0.796, 95% CI: 0.708-0.884, P < 0.001). The presence of well-developed CC could independently predict with high accuracy myocardial viability assessed by LGE in territories subtended by CTO vessels. Therefore, search for viable myocardium using different imaging modalities, e.g. CMR, may be recommended in CTO patients with well-developed CC.

Coronary Angiography Characteristics as Predictor of Successful Chronic Total Occlusion Recanalization

Although remarkable progress in percutaneous coronary intervention (PCI) has been achieved over the last decade, the success rate of chronic total occlusion (CTO) recanalization varies greatly. Coronary angiography characteristics may affect the success rate of CTO recanalization. This study sought to establish a scoring model to predict successful CTO recanalization based on coronary angiography characteristics. We analyze 287 angiography data from patients who underwent elective PCI. Angiography characteristics being measured were lesion location, blunt stump, calcification, ostial lesion, bridging collateral, bending, side branch, tortuosity, previous stent attempt, and lesion length of >20 mm. Data were analyzed using SPSS 25.0. Multivariate analysis shows that side branch lesion ( p  = 0.000), proximal vessels tortuosity ( p  = 0.015), calcified lesion ( p  = 0.000), lesion length of >20 mm ( p  = 0.000), and blunt stump ( p  = 0.000) can predict the successful PCI in the CTO. ROC curve analysis of the score ability to predict successful PCI in the CTO showed area under curve of 0.89 (confidence interval 95%), the cutoff point of ≤2 with a sensitivity of 93.33%, and specificity of 88.23%. We concluded that the five angiography characteristics that strongly associate with successful PCI in the CTO are calcified lesion, blunt stump, lesion length >20 mm, proximal vessel tortuosity, and side branch lesion. This score may help cardiologists to predict the success probability of PCI in the CTO.

The hybrid algorithm in treatment of coronary chronic total occlusions - MSWiA Lublin CTO 5-year registry

INTRODUCTION

Treatment of chronic total occlusions (CTO) despite improvement in techniques and results over the last years still seems to be limited to a small number of centres and operators. Application of the hybrid strategy may support further spread of CTO percutaneous coronary intervention (PCI) and increase procedural success rates.

AIM

Our single-centre prospective ongoing registry aims to provide details and results of recanalizations of coronary CTO performed according to the hybrid algorithm in a series of consecutive patients.

MATERIAL AND METHODS

Between January 2015 and September 2019 the clinical and procedural data of CTO PCI procedures on consecutive patients were collected. Lesion complexity was assessed according to the Multicenter CTO Registry of Japan (J-CTO) score: 0 - easy, 1 - intermediate, 2 - difficult, ≥ 3 - very difficult and PROGRESS score. Strategies applied were classified as: antegrade wire escalation (AWE), antegrade dissection and re-entry (ADR), retrograde wire escalation (RWE) and retrograde dissection and re-entry (RDR). Angiographic success was defined as < 30% residual stenosis with TIMI 3 flow. Angiographic and clinical complications were reported.

RESULTS

Two hundred sixty-six patients were included and 285 procedures were performed in total. Success rate was 87.7% (calculated per procedure) and 92.5% (calculated per patient). Four patients underwent successful staged double CTO recanalization. Fifteen patients out of 31 primary failures underwent a second attempt with a 73% success rate (11/15). Fifty-two patients (18.2%) were referred for a second attempt from other institutions. Mean J-CTO score was 2.6 (13 cases with J-CTO of 0, 41 cases with J-CTO of 1, 80 cases with J-CTO of 2, and 151 cases with J-CTO ≥ 3) and the success rate was respectively 92.3%, 95.1%, 91.3% and 83.4%. Higher complexity of occlusion required a higher number of applied strategies including retrograde access in over a quarter of cases. Complete revascularization was achieved in 215 (75.4%) cases. In-hospital MACCE rate was 3.5% - 1 patient died due to acute kidney injury complications, 9 (3.2%) patients sustained myocardial infarction (1 STEMI due to side branch occlusion). All 7 (2.5%) coronary perforations (Ellis 1 and Ellis 2) were treated conservatively and we recognised 10 (3.5%) cases of acute kidney injury (one dialysis).

CONCLUSIONS

The hybrid algorithm in CTO PCI can be successfully applied with good early results and low complication rates. Higher complexity CTOs require more procedural strategies with a significantly lower success rate in very difficult cases.

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.

Active Retrograde Extra Backup with a Mother-and-Child Catheter to Facilitate Retrograde Microcatheter Collateral Channel Tracking in Recanalization of Coronary Chronic Total Occlusion

OBJECTIVE

To explore the feasibility and safety of the active retrograde backup (ARB) for treatment of chronic total occlusion (CTO) during retrograde percutaneous coronary intervention (PCI).

BACKGROUND

Guiding support plays an important role in guidewire and microcatheter coronary channel (CC) tracking in retrograde PCI therapy for patients with CTO. However, the feasibility and safety of retrograde active use of a mother-and-child catheter are still unclear. Patients and Methods. A total of 271 consecutive patients with CTO who underwent retrograde PCI between January 2015 and January 2020 were retrospectively analyzed. Clinical data of two groups were compared to evaluate the feasibility and safety of ARB.

RESULTS

Of the 271 patients, 69.0% (187/271) underwent therapy through the septal branch, 31.0% (84/271) through the epicardial collateral channel, and 47.6% (129/271) through active retrograde extra backup with a mother-and-child catheter to facilitate retrograde microcatheter collateral CC tracking. The time of wire CC tracking was shorter in the ARB group than that in the non-ARB group (25.4 ± 8.5 vs 26.4 ± 9.7, p=0.348), but there was no significant difference. The duration of the retrograde microcatheter tracking (10.2 ± 3.8 vs 15.5 ± 6.8, p=0.012) and the retrograde approach (62.8 ± 20.3 vs 70.4 ± 24.3, p=0.026) in the ARB group was significantly shorter than that in the non-ARB group. The radiation dose (223.6 ± 112.7 vs. 295.2 ± 129.3, p=0.028), fluoroscopy time (50.6 ± 21.3 vs 62.3 ± 32.1, p=0.030), and contrast volume (301.8 ± 146.7 vs 352.2 ± 179.5, p=0.032) in the ARB group were significantly lower than that in the non-ARB group. There were no life-threatening procedural complications in either group. Complications unrelated to ARB included two cases of donor-vessel dissection, one case of CC perforation, and two cases of target-vessel perforation. There was no statistically significant difference in major adverse cardiac and cerebrovascular events between the groups during hospitalization (p > 0.05).

CONCLUSION

ARB is feasible, safe, and conducive to guidewire and microcatheter CC tracking in the recanalization of coronary CTO. It improves procedural efficiency and is worthy of further promotion.

Procedural and In-hospital Outcomes of Rotational Atherectomy in Retrograde Coronary Chronic Total Occlusion Intervention

Coronary chronic total occlusions (CTOs) are characterized by a high incidence of severe plaque calcifications, which are associated with a high use of the retrograde approach and a low success rate of percutaneous coronary intervention (PCI). However, the feasibility of rotational atherectomy (RA) in retrograde CTO-PCI remains unknown. The aim of the present study is to examine the safety and efficacy of RA in retrograde CTO-PCI. Consecutive patients (n = 129) who underwent RA during CTO-PCI were categorized into anterograde and retrograde groups according to the CTO crossing approach. The distributions of the baseline characteristics were similar in the 2 groups, but the lesion type was more complex (P = .001), and the starting burr size was smaller (P = .003) in the retrograde group than in the anterograde group. There was a trend of a higher incidence of procedural complications in the retrograde group than in the anterograde group (P = .054). Technical and procedural success and in-hospital outcomes were not significantly different between the 2 groups. In conclusion, RA was feasible in retrograde CTO PCI, but some specific precautions are required before and during the procedure. In addition, further investigation of the long-term outcomes of RA in retrograde CTO PCI is necessary.

Prognosis of Patients With Reduced Left Ventricular Ejection Fraction and Chronic Total Occlusion According to Treatment Applied

BACKGROUND

Chronic total occlusion (CTO) is common among patients with coronary artery disease. Very few studies have focused on outcomes of patients with CTO and reduced left ventricular ejection fraction (LVEF), according to treatment applied. The aim of our study was to determine the potential influence of the selected treatment on the prognosis in patients with CTO associated with reduced LVEF.

METHODS

Between June 2010 and October 2013, all consecutive patients with at least one CTO and reduced LVEF (<40%) were enrolled. Major adverse cardiac events (MACE), defined as the composite of cardiac mortality or myocardial infarction (MI) and its individual components, were compared between three treatment groups: medical therapy (MT), percutaneous coronary intervention (PCI), and coronary bypass graft (CABG).

RESULTS

In 256 included patients, the follow-up was 1129 ± 556 days. The incidence of MACE was 40% in the MT group, compared with PCI (20.3%) and CABG (16.7%); p < 0.001. All-cause and cardiac mortality were also higher in the MT group (40.7% and 33.3%, respectively) versus the PCI (21.9% and 15.6%) and CABG (11.9% and 9.5%) groups (p < 0.001 for both endpoints); MI rate did not differ among groups. In the adjusted multivariate analysis, CABG had lower MACE risk, compared with MT (HR = 0.39, 0.17-0.91; p = 0.029); successful PCI also trended toward lower risk of MACE, compared with MT.

CONCLUSIONS

Patients with CTO and reduced LVEF treated with MT had a worse prognosis than those treated with revascularization (either CABG or PCI). Patients with an indication for CABG appeared to perform best during long-term follow-up.

Relationship between Coronary Iodine Concentration Determined Using Spectral CT and the Outcome of Percutaneous Coronary Intervention in Patients with Chronic Total Occlusion

PURPOSE

To evaluate the feasibility of coronary iodine concentration (CIC) by using spectral CT in the assessment of the outcome of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO).

MATERIALS AND METHODS

In total, 50 consecutive patients underwent preprocedural coronary CT angiography with spectral CT prior to their staged PCI for CTO between June 2017 and July 2018. Iodine density maps, referred to as iodine-no-water maps throughout, with spectral CT provided the CIC at proximal CTO (CTO-CIC). Depending on the outcome of PCI, all CTO lesions were divided into two groups: failed PCI and successful PCI. The receiver operating characteristic curve was used to determine the cutoff values of CTO-CIC in the assessment of the outcome of PCI for CTO.

RESULTS

Of the 50 CTO lesions in 50 patients, 34 (68%) and 16 (32%) were assigned to the successful PCI and failed PCI groups, respectively. The mean CTO-CIC was significantly less in the failed PCI group than in the successful PCI group (1.3 mg/mL ± 0.9 [standard deviation] vs 5.2 mg/mL ± 2.5; P < .001). A low CTO-CIC (≤ 2.5 mg/mL) predicted failed PCI with 87% sensitivity, 79% specificity, 79% positive predictive value, and 90% negative predictive value. At multivariable analysis, the low CTO-CIC was significantly associated with the failed PCI (odds ratio, 27.0; 95% confidence interval: 4.9, 147.6; P < .0001).

CONCLUSION

The CTO-CIC determined by using spectral CT may be useful in the assessment of the outcome of staged PCI for CTO.See also the commentary by Rubinshtein and Blankstein in this issue.© RSNA, 2020.

Association of Operator and Hospital Experience With Procedural Success Rates and Outcomes in Patients Undergoing Percutaneous Coronary Interventions for Chronic Total Occlusions

Background:

An inverse relationship has been described between procedural success and outcomes of all major cardiovascular procedures. However, this relationship has not been studied for percutaneous coronary intervention (PCI) of chronic total occlusion (CTO).

Methods:

We analyzed the data on patients enrolled in Blue Cross Blue Shield of Michigan Cardiovascular Consortium registry in Michigan (January 1, 2010 to March 31, 2018) to evaluate the association of operator and hospital experience with procedural success and outcomes of patients undergoing CTO-PCI. CTO-PCI was defined as intervention of a 100% occluded coronary artery presumed to be ≥3 months old.

Results:

Among 210 172 patients enrolled in the registry, 7389 (3.5%) CTO-PCIs were attempted with a success rate of 53%. CTO-PCI success increased with operator experience (45% and 65% in the lowest and highest experience tertiles) and was the highest for highly experienced operators at higher experience centers and the lowest for inexperienced operators at low experience hospitals. Multivariable logistic regression models (with spline transformed prior operator and institutional experience) demonstrated a positive relationship between prior operator and site experience and procedural success rates (likelihood ratio test=141.12, df=15, P <0.001) but no relationship between operator and site experience and major adverse cardiac event (likelihood ratio test=19.12, df=15, P =0.208).

Conclusions:

Operator and hospital CTO-PCI experiences were directly related to procedural success but were not related to major adverse cardiac event among patients undergoing CTO-PCIs. Inexperienced operators at high experience centers had significantly higher success but not major adverse cardiac event rates compared with inexperienced operators at low experience centers. These data suggested that CTO-PCI safety and success could potentially be improved by selective referral of these procedures to experienced operators working at highly experienced centers.

Vulnerability for ventricular arrhythmias in patients with chronic coronary total occlusion

INTRODUCTION

The presence of a chronic total occlusion (CTO) is associated with an increased risk of ventricular arrhythmias.

AREAS COVERED

This review provides an overview of the relationship between CTO and ventricular arrhythmias, arrhythmogenic mechanisms, and the effect of revascularization.

EXPERT OPINION

Studies in recipients of an implantable cardioverter-defibrillator (ICD) have shown that a CTO is an independent predictor of appropriate ICD therapy. The myocardial territory supplied by a CTO is a pro-arrhythmogenic milieu characterized by scar tissue, large scar border zone, hibernating myocardium, residual ischemia despite collaterals, areas of slow conduction, and heterogeneity in repolarization. Restoring coronary flow by revascularization might be associated with electrical homogenization as reflected by a decrease in QT(c) dispersion, decrease in T wave peak-to-end interval, reduction of late potentials, and decrease in scar border zone area. Future research should explore whether CTO revascularization results in a lower burden of ventricular arrhythmias. Furthermore, risk stratification of CTO patients without severe LV dysfunction is interesting to identify potential ICD candidates. Potential tools for risk stratification are the use of electrocardiographic parameters, body surface mapping, electrophysiological study, and close rhythm monitoring using an insertable cardiac monitor.

Long term clinical impact of successful recanalization of chronic total occlusion in patients with and without type 2 diabetes mellitus

BACKGROUND

Diabetes mellitus is one of the risk factors for coronary artery disease and frequently associated with multivessels disease and poor clinical outcomes. Long term outcome of successful revascularization of chronic total occlusions (CTO) in diabetes patients remains controversial.

METHODS AND RESULTS

From January 2005 to December 2015, 739 patients who underwent revascularization for CTO in Taipei Veterans General Hospital were included in this study, of which 313 (42%) patients were diabetes patients. Overall successful rate of revascularization was 619 (84%) patients whereas that in diabetics and non-diabetics were 265 (84%) and 354 (83%) respectively. Median follow up was 1095 days (median: 5 years, interquartile range: 1-10 years). During 3 years follow-up period, 59 (10%) in successful group and 18 (15%) patients in failure group died. Although successful revascularization of CTO was non-significantly associated with better outcome in total cohort (hazard ratio (HR): 0.593, 95% confidence interval (CI) 0.349-0.008, P: 0.054), it might be associated with lower risk of all-cause mortality (HR: 0.307, 95% CI 0.156-0.604, P: 0.001) and CV mortality (HR: 0.266, 95% CI 0.095-0.748, P: 0.012) in diabetics (P: 0.512). In contrast, successful CTO revascularization didn't improve outcomes in non-diabetics (all P > 0.05). In multivariate cox regression analysis, successful CTO revascularization remained an independent predictor for 3-years survival in diabetic subgroup (HR: 0.289, 95% CI 0.125-0.667, P: 0.004). The multivariate analysis result was similar after propensity score matching (all-cause mortality, HR: 0.348, 95% CI 0.142-0.851, P: 0.021).

CONCLUSIONS

Successful CTO revascularization in diabetes may be related to better long term survival benefit but not in non-diabetic population.