Meta-analysis on the impact of percutaneous coronary intervention of chronic total occlusions on left ventricular function and clinical outcome

Assessment of chronical total occlusions management in France: The ENCOCHE Registry, a prospective, multicentric study

BACKGROUND

Coronary chronic total occlusions (CTO) are frequent, and coronary angioplasty has been increasingly used in recent years for lesion revascularisation. However, to date, no dedicated multicentric prospective study is available in France.

AIM

To describe the characteristics of CTO patients and to assess current treatment strategies in French catheterisation laboratory practice.

METHODS

Patients presenting with CTOs were included from 16/09/2021 to 13/12/2021 over two consecutive prospective phases. In phase I (one month), data were collected to include all patients presenting CTO at diagnostic angiography. In phase II (two months), data were collected focusing on patients who underwent CTO-PCI.

RESULTS

A total of 1303 patients (1460 CTOs) were included in 68 French centres. The mean age was 67.7±10.7 years and 84.3% of the patients were men. The prevalence of prior PCI (44.6%), and diabetes mellitus (35.6%) was high. In phase I, multivessel coronary artery disease was detected in two-thirds of cases, and most of them (88.5%) had a single CTO. The mean J-CTO score was 1.9±1.2, with a proportion of difficult and very difficult CTO (J CTO score ≥2) of 61.1%. The selected treatment was medical therapy in 57% of cases, coronary angioplasty in 30% and bypass surgery in 13%. In phase II, 528 patients were included with a mean J-CTO score of 1.8±1.2. Successful guidewire crossing through CTO lesion was obtained with an antegrade access in 89% of patients. Procedural success rate of CTO-PCI was 80%, with a rate of major in-hospital complications of 1% (death: 0.4%, MI: 0.2%, stroke: 0.2%, emergency CABG: 0.2%).

CONCLUSION

This prospective study provides a snapshot of CTOs prevalence and CTO treatment strategies in France in 2021.

Advances in Technology and Technique in Percutaneous Coronary Intervention: A Clinical Review

Percutaneous coronary intervention (PCI) has become the standard procedure for patients with angina and acute coronary syndrome. From the perspective of technology and technique, PCI has advanced over the last four decades, resulting in considerably improved clinical outcomes in patients with coronary artery disease in the current era. In this review article, we summarize recent advances, promising technologies, and areas for research in the field of PCI.

N terminal pro-brain natriuretic peptide level and benefits of chronic total occlusion revascularization

BACKGROUND

The management of revascularization of chronic total occlusions (CTOs) remains controversial. Whether specific patients gain survival benefit from CTO revascularization remains unknown.

OBJECTIVES

We investigated whether (i) patients with CTO have higher N terminal pro-brain natriuretic peptide (NT pro-BNP) levels than patients without CTO, (ii) in patients with CTO, NT pro-BNP levels predict adverse events, and (iii) those with elevated levels benefit from revascularization.

METHODS

In 392 patients with stable, significant coronary artery disease (CAD) and CTO undergoing coronary angiography, rates of all-cause mortality, cardiovascular death, and a composite (cardiovascular death, myocardial infarction and heart failure hospitalizations) were investigated. Unadjusted and adjusted Cox proportional and Fine and Gray sub-distribution hazard models were performed to determine the association between NT pro-BNP levels and incident event rates in patients with CTO.

RESULTS

NT pro-BNP levels were higher in patients with, compared to those without CTO (median 230.0 vs. 177.7 pg/mL, p ≤0.001). Every doubling of NT pro-BNP level in patients with CTO was associated with a > 25% higher rate of adverse events. 111 (28.5%) patients underwent CTO revascularization. In patients with elevated NT pro-BNP levels (> 125 pg/mL), those who underwent CTO revascularization had substantially lower adverse event rates compared to patients without CTO revascularization (adjusted cardiovascular death hazard ratio 0.29, 95% confidence interval (0.09-0.88). However, in patients with low NT pro-BNP levels (≤ 125 pg/mL), event rates were similar in those with and without CTO revascularization.

CONCLUSION

NT pro-BNP levels can help identify individuals who may benefit from CTO revascularization.

20 years of treating ischemic cardiomyopathy with mesenchymal stromal cells: a meta-analysis and systematic review

This meta-analysis and systematic review compiles comparative data from 2004 to 2024, investigating the safety and efficacy of mesenchymal stem/stromal cells (MSCs) derived from various tissues for the treatment of ischemic cardiomyopathy (ICM) and associated heart failure. In addition, this review highlights the limitations of these interventions and provides valuable insights for future therapeutic approaches. Relevant articles were retrieved from the PubMed® database using targeted keywords. Our inclusion criteria included clinical trials with patients over 18 years of age, case reports and pilot studies. Animal experiments, in vitro studies, correlational and longitudinal studies, and study designs and protocols were excluded. Forty-nine original articles resulted in follow-up reports of 45 trials. MSCs from bone marrow, umbilical cord and adipose tissue were moderately well tolerated. Of the 1408 participants who received MSCs, 33 trials (67.3%) reported the occurrence of death or serious adverse events. These events resulted in 80 deaths (52% of reported cases) following MSC administration. Importantly, 41.3% of these deaths (n = 33) were not considered to be related to the intervention itself, while 40% of these deaths had no reported cause. As the primary outcome, the mean increase in left ventricular ejection fraction (LVEF) from baseline was 5.75% (95% CI: 3.38% -8.11%, p < 0.0001, I2 = 90,9%) in the randomized controlled trials only (n = 24) within the treatment groups and 3.19% (95% CI: 1.63% to 4.75%, p < 0.0001, I2 = 74,17%) in the control groups after the intervention. When the above results were compared using the standardized mean difference (SDM), a significance in favor of the treatment group was also found (SDM = 0.41; 95% CI: 0.19-0.64, p < 0.001, I2 = 71%). Although improvements were also seen in the control groups, 33.3% (n = 15) of the studies showed no significant difference between the control and treatment groups. The 6-minute walking test (6MWT) and New York Heart Association (NYHA) class scores, used for assessing exercise tolerance and quality of life (QoL), respectively, further supported the improvements in the treatment group. These improvements were noted as 62.5% (n = 10) for the 6MWT and 54.5% (n = 12) for the NYHA class scores. According to the risk of bias analysis, 4 trials were of good quality (11.8%), 15 were of fair quality (44.1%), and 15 were of poor quality (44.1%). Major limitations of these studies included small sample size, diagnostic challenges/lack, uncertain cell dosage and potential bias in patient selection. Despite the ongoing debate surrounding cell administration for ICM, there are supporting signs of improved clinical and laboratory outcomes, as well as improved QoL in the MSC-treated groups. However, it is important to recognize the limitations of each study, highlighting the need for larger, controlled trials to validate these findings.

Chronic Total Occlusions: A State-of-the-Art Review

The percutaneous management of chronic total occlusions (CTO) is a well-established sub-specialty of Interventional Cardiology, requiring specialist equipment, training, and techniques. The heterogeneity of approaches in CTO has led to the generation of multiple algorithms to guide operators in their management. The evidence base for management of CTOs has suffered from inconsistent descriptive and quantitative terminology in defining the nature of lesions and techniques utilised, as well as seemingly contradictory data about improvement in ventricular function, symptoms of angina, and mortality from large-scale registries and randomised controlled trials. Through this review, we explore the history of CTO management and its supporting evidence in detail, with an outline of limitations of CTO-percutaneous coronary intervention and a look at the future of this growing field within cardiology.

Percutaneous Coronary Intervention versus Optimal Medical Therapy in Patients with Chronic Total Occlusion: A Meta-Analysis

Background/Objectives: Chronic total occlusion (CTO) is a prevalent finding in patients with coronary artery disease and is associated with increased mortality. Prior reports on the efficacy of percutaneous coronary intervention (PCI) compared to optimal medical therapy (OMT) were controversial. Following the emergence of recently published new evidence, a meta-analysis is warranted. The current meta-analysis assessed the effects of PCI compared to OMT in the treatment of CTO. Methods: A structured literature search was performed. Randomized controlled trials (RCTs) and non-randomized controlled studies of interventions were eligible. The primary outcome was an accumulated composite of cardiac mortality, myocardial infarction and target vessel/lesion revascularization events. Results: Thirty-two studies reporting on 11260 patients were included. Of these, 5712 (50.7%) were assigned to the PCI and 5548 (49.3%) were allocated to the OMT group. The primary outcome occurred in 14.6% of the PCI and 20.1% of the OMT group (12 trials, OR 0.66, 95% CI 0.50 to 0.88, p = 0.005, I2 = 67%). Subgrouping demonstrated a consistent reduction in the primary outcome for the PCI group in RCTs (six trials, OR 0.58, 95% CI 0.33 to 0.99, p = 0.05). The primary outcome reduction was irrespective of the study design, and it was replicable in sensitivity and subgroup analyses. Advantages in other outcomes were rather related to statistical pooling effects and dominated by observational data. Conclusions: CTO-PCI was associated with improved patient-oriented primary outcome compared to OMT in a study-level meta-analysis. This composite outcome effect was mainly driven by target vessel treatment, but a significant reduction in mortality and myocardial infarction was observed, irrespectively. These findings have hypothesis-generating implications. Future RCTs with adequate statistical power are eagerly awaited.

Long-term improvement of symptoms of angina pectoris after successful revascularization of coronary artery chronic total occlusions

Objectives. To compare long-term angina pectoris relief of successful versus failed percutaneous coronary intervention of chronic total occlusions (CTO PCI). Background. Previous studies demonstrate better short-term angina pectoris relief of CTO PCI than with optimal medical treatment (OMT), however, data on the long-term effects are lacking. Methods. 295 patients undergoing CTO PCI were analyzed retrospectively, with a follow-up evaluation of symptoms of angina pectoris and all-cause death one to four years after the intervention. The primary outcome was long-term relief of symptoms of angina pectoris. Secondary outcomes included a composite of major adverse cardiovascular events (MACE), including all-cause death, myocardial infarction, stroke, and later target vessel revascularization (TVR). At follow-up, patients were interviewed for symptoms of angina pectoris at 1, 6, 12, and 22 to 48 months after the intervention. Results. CTO PCI was successful in 225 (76%) patients and failed in 70 (24%) patients. Short-term (six months) relief of angina pectoris was observed in both groups, but only the successful CTO PCI group showed long-term relief. The Kaplan-Meier curves of all-cause death did not differ between the groups (p = .715). The final follow-up was a mean (range) of 37 (25 to 44) months after the intervention in the successful CTO PCI group, and 33 (28 to 48) months in the failed CTO PCI group. Conclusions. Successful CTO PCI is associated with better long-term relief of symptoms of angina pectoris compared to failed CTO PCI.

High Sensitivity Troponin Level and Benefits of Chronic Total Occlusion Revascularization

Background The survival benefit of revascularization of chronic total occlusion (CTO) of the coronary arteries remains a subject of controversy. We measured high sensitivity troponin-I (hsTn-I) levels as an estimate of myocardial ischemia in patients with stable coronary artery disease, with the hypothesis that (1) patients with CTO have higher levels of hsTn-I than patients without CTO, (2) hsTn-I levels will predict adverse cardiovascular events in patients with CTO, and (3) patients with elevated hsTn-I levels will have a survival benefit from CTO revascularization. Methods and Results In 428 patients with stable coronary artery disease and CTO undergoing coronary angiography, adverse event rates were investigated. Cox proportional hazards models and Fine and Gray subdistribution hazard models were performed to determine the association between hsTn-I level and incident event rates in patients with CTO. HsTn-I levels were higher in patients with compared with those without CTO (median 6.7 versus 5.6 ng/L, P=0.002). An elevated hsTn-I level was associated with higher adverse event rates (adjusted all-cause mortality hazard ratio, 1.19 [95% CI, 1.08-1.32]; P=0.030) for every doubling of hsTn-I level. CTO revascularization was performed in 28.3% of patients. In patients with a high (>median) hsTn-I level, CTO revascularization was associated with substantially lower all-cause mortality (adjusted hazard ratio, 0.26 [95% CI, 0.08-0.88]; P=0.030) compared with those who did not undergo revascularization. In patients with a low ( Collapse

Key Words

• chronic total occlusion
• coronary artery bypass graft
• high sensitivity troponin‐I
• percutaneous coronary intervention

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MESH Headings

• Humans
• Coronary Artery Disease/complications
• Coronary Occlusion
• Risk Factors
• Treatment Outcome
• Percutaneous Coronary Intervention/adverse effects
• Coronary Angiography/adverse effects
• Chronic Disease
• Troponin I

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Grants

• U54 AG062334 NIA NIH HHS
• P01 HL154996 NHLBI NIH HHS
• R33 HL138657 NHLBI NIH HHS
• P01 HL086773 NHLBI NIH HHS
• P30 DK111024 NIDDK NIH HHS
• R01 HL109413 NHLBI NIH HHS
• R01 HL166004 NHLBI NIH HHS
• R61 HL154116 NHLBI NIH HHS
• P20 HL113451 NHLBI NIH HHS
• P01 HL101398 NHLBI NIH HHS

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Affiliation(s)

Daniel A. Gold Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Pratik B. Sandesara Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Vardhmaan Jain Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Matthew E. Gold Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Nishant Vatsa Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Shivang R. Desai Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Malika Elhage Hassan Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Chenyang Yuan Department of Biostatistics and Bioinformatics, Rollins School of Public HealthEmory UniversityAtlantaGA
Yi‐An Ko Department of Biostatistics and Bioinformatics, Rollins School of Public HealthEmory UniversityAtlantaGA
Ayman Alkhoder Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Kiran Ejaz Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Zain Alvi Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Alireza Rahbar Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Gillian Murtagh Abbott Diagnostics, Abbott LaboratoriesAbbott ParkIL
Wissam A. Jaber Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
William J. Nicholson Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Arshed A. Quyyumi Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA

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Baseline angina burden predicts quality of life and functional improvement in patients with viable myocardium treated for chronic total occlusion

Chronic total occlusion (CTO) is a common finding in patients with known or suspected coronary artery disease and has a distinctive role in these patients' quality of life. However, there is still a lack of evidence of correct patient selection for percutaneous coronary intervention (PCI). From July 2017 to August 2020, 68 patients with successful PCI of a CTO and previous evidence of viability for PCI by cardiovascular magnetic resonance imaging (CMR) were prospectively included in this single-centre observational study. Of these patients, 62 underwent follow-up CMR, and 56 underwent surveys using the Seattle Angina Questionnaire before PCI and 3, 12 and 24 months after PCI. The CMR results were assessed for volumetric, functional and deformation parameters. From the baseline to the follow-up, there was a significant reduction in the left ventricular volumes (all p < 0.001) and an increase in the left ventricular ejection fraction (57.6 ± 11.6% vs. 60.3 ± 9.4%, p = 0.006). Among the deformation parameters, only the left ventricular radial strain showed significant improvement. The SAQ showed an early improvement that emphasised angina stability and frequency as well as a summary score, which persisted after 24 months. A low SAQ summary score before PCI was the best predictive factor of good clinical improvement thereafter. Improvements in myocardial function and quality of life can be achieved with PCI of a CTO. Patient selection for PCI should be performed primarily among relevantly symptomatic patients when evidence of viability for PCI is present. The SAQ can help guide such patient selection.Trial registration ISRCTN, identifier: ISRCTN33203221. Retrospectively registered on 01.04.2020. https://www.isrctn.com/ISRCTN33203221.

Short- and Long-term Outcomes of Percutaneous Coronary Interventions in Chronic and Non-chronic Total Occlusions: A Meta-analysis of 690,123 Patients

The use of percutaneous coronary intervention (PCI) in patients with chronic total occlusion (CTO) is still a subject of debate, with conflicting outcomes reported in different studies when compared to non-CTO lesions. This meta-analysis aims to clarify the clinical outcomes of PCI in CTO cases compared to non-CTO lesions, both in the short and long-term. PubMed, Scopus, Web of Science, Ovid, and Cochrane Central were searched until March 2023 for relevant studies addressing short- and long-term outcomes of PCI in CTO vs non-CTO lesions. Dichotomous data were pooled as odds ratio (OR) with its 95% confidence interval (CI) in a random Der-Simonian lair effect model using STATA 17 MP. Eight studies with a total of 690,123 patients were included. In terms of short-term outcomes, CTO PCI was associated with higher rates of vessel perforation (OR = 2.16, 95% CI: 1.31-3.57) and cardiac tamponade (OR = 5.19, 95% CI: 4.29-6.28). Additionally, CTO PCI showed lower rates of procedural success (OR = 0.84, 95% CI: 0.73-0.96). Moreover, in the long-term, CTO PCI had higher rates of MACE (OR = 1.02, 95% CI: 1.01-1.04), however, it showed lower rates of cardiac death (OR = 0.61, 95% CI: 0.38-0.98), with no significant difference in other reported outcomes. Our findings underscore the challenges and adverse outcomes associated with using PCI to treat CTO lesions in the short term. This suggests that interventional cardiologists should carefully evaluate the risks and benefits before proceeding with PCI in CTO lesions.

International randomized trial on the effect of revascularization or optimal medical therapy of chronic total coronary occlusions with myocardial ischemia - ISCHEMIA-CTO trial - rationale and design

BACKGROUND

Chronic total occlusions (CTO) are frequent among patients with coronary artery disease. Revascularization with percutaneous coronary intervention (PCI) is safe and feasible in experienced hands. However, randomized data are needed to demonstrate symptomatic as well as prognostic effect of CTO-PCI compared to optimal medical therapy alone.

METHODS

This trial aims to evaluate the effect of CTO PCI in patients with a CTO lesion and target vessel diameter ≥ 2.5 mm, and myocardial ischemia in the relevant territory. First, all patients are subjected to optimal medical therapy (OMT) for at least for 3 months and non-CTO lesions are managed according to guidelines. Subsequently, prior to randomization myocardial ischemia and quality of life (Seattle Questionnaire (SAQ)) is assessed. Patients are divided into two cohorts based on their SAQ score and randomized to either OMT alone or OMT and CTO-PCI. Cohort A is defined as Low- or asymptomatic patients with a quality-of-life score > 60 and/or CCS class < 2, and more than 10 % ischemia in the left ventricle (LV). Cohort B is symptomatic patients with a quality-of-life score < 60 or CCS class angina > 1 and at least ischemia in 5% of the LV. The primary end-point in cohort A is a composite of major adverse cardiac and cerebral events, hospitalization for heart failure and malignant ventricular arrhythmias. The primary endpoint in cohort B is difference in quality of life 6 months after randomization.

IMPLICATIONS

This trial is designed to investigate if CTO-PCI improves QoL and MACCE. Both positive and negative outcome of the trial will affect future guidelines and recommendations on how to treat patients with CTO.

In-Hospital Outcomes of Chronic Total Occlusion Percutaneous Coronary Interventions in Heart failure patients

In-hospital outcomes of chronic total occlusion Percutaneous Coronary Interventions (CTO PCI) in heart failure patients has not been evaluated on a national base and was the focus of this investigation. We used the Nationwide Inpatient Sample database from 2008 to 2014 to identify adults with single vessel CTO PCI for stable ischemic heart disease (SIHD). Patients were divided into 3 groups: patients without heart failure, heart failure with reduced ejection fraction (HFrEF) and heart failure with preserved ejection fraction (HFpEF). Clinical characteristics and in-hospital outcomes were studied using relevant statistics. Multiple logistic regression models were performed to assess in-hospital mortality, acute renal failure, and the use of mechanical support devices. Of 112,061 inpatients with SIHD from 2008 to 2014 undergoing CTO PCI, 21,185 (19%) had HFrEF and 3309 (3%) had HFpEF. Compared to patients without heart failure, HFrEF and HFpEF patients were older (mean age 69.2 vs 66.3, 70.3 vs 66.3 respectively, P < 0.001), had more comorbidities and higher acute in-hospital complications. HFrEF patients had higher adjusted in-hospital mortality [AOR 1.73, 95% CI (1.21-2.48)], acute renal failure [AOR 2.68, 95% CI (2.34-3.06)], and need for mechanical support [AOR 2.76, 95% CI (2.17-3.51)]. Compared to patients without heart failure, HFpEF patients had similar mortality and need for mechanical support, but higher incidence of acute renal failure. Older age was significantly associated with increased in-hospital mortality. chronic total occlusion PCI in patients with heart failure is associated with higher in-hospital morbidity and mortality and warrants further investigation to optimize health care delivery.

Long-term follow-up of patients with chronic total coronary artery occlusion previously randomized to treatment with optimal drug therapy or percutaneous revascularization of chronic total occlusion (COMET-CTO)

Background

The COMET-CTO trial was a randomized prospective study that assessed long-term follow-up in patients with chronic total occlusion (CTO) in coronary arteries treated with percutaneous coronary intervention (PCI) or with optimal medical therapy (OMT). During the 9-month follow-up, the incidence of major adverse cardiac events (MACE) did not differ between the two groups; no death or myocardial infarction (MI) was observed. There was a significant difference in quality of life (QoL), assessed by the Seattle Angina Questionnaire (SAQ), in favor of the PCI group. Here we report long-term follow-up results (56 ± 12 months).

Methods

Between October 2015 and May 2017, a total of 100 patients with CTO were randomized into two groups of 50 patients: PCI CTO or OMT group. The primary endpoint of the current study was the incidence of MACE defined as cardiac death, MI, and revascularization [PCI or coronary artery bypass graft (CABG)]. As the secondary exploratory outcome, we analyzed all the cause-mortality rate.

Results

Out of 100 randomized patients, 92 were available for long-term follow-up (44 in the PCI group and 48 in the OMT group). The incidence of MACE did not differ significantly between the two groups (p = 0.363). Individual components of MACE were distributed, respectively: cardiac death (OMT vs. PCI group, 6 vs. 3, p = 0.489), MI (OMT vs. PCI group, 1 vs. 0, p = 1), and revascularization (PCI: OMT vs. PCI group, 2 vs. 2, p = 1; CABG: OMT vs. PCI group, 1 vs. 1, p = 1). There was no significant difference between the two groups regarding the individual component of MACE. Six patients died from non-cardiac causes [five deaths were reported in the OMT group and one death in the PCI group (p = 0.206)]. Kaplan-Meier survival curves for MACE did not differ significantly between the study groups (log-rank 0.804, p = 0.370). Regarding the secondary exploratory outcome, a total of 15 patients died at 56 ± 12 months (11 in the OMT and 4 in the PCI group) (p = 0.093). The Kaplan-Meier survival curves for all-cause mortality rates did not differ significantly between the two groups (log rank 3.404, p = 0.065). There were no statistically significant differences between OMT and PCI groups in all five SAQ domains. There was a significant improvement in three SAQ domains in the PCI group: PL (p < 0.001), AF (p = 0.007), and QoL (p = 0.001).

Conclusion

After 56 ± 12 months of follow-up, the incidence of MACE, as well as QoL measured by SAQ, did not differ significantly between the PCI and OMT groups.

Impact of percutaneous coronary intervention on chronic total occlusion in the non-infarct-related artery in patients with STEMI: a systematic review and meta-analysis

OBJECTIVES

We sought to compare the clinical outcomes between culprit-only percutaneous coronary intervention (PCI) versus multivessel PCI (MV-PCI) in patients with ST-segment elevation myocardial infarction (STEMI) accompanied by chronic total occlusion (CTO) in the non-infarct-related artery(non-IRA).

DESIGN

Studies that compared culprit-only PCI versus MV-PCI in patients with STEMI accompanied by CTO in the non-IRA were included. Random odds ratio (OR) and 95% confidence interval (CI) were calculated.

RESULTS

Eight studies with 2,259 patients were included. The results suggested that in patients with STEMI accompanied by CTO in the non-IRA, culprit-only PCI was associated with higher risks of all-cause mortality (OR: 2.89; 95% CI: 2.09-4.00; I² = 0.0%), cardiac death (OR: 3.12; 95% CI: 2.05-4.75; I² = 16.8%), stroke (OR: 2.80; 95% CI: 1.04-7.53; I² = 0.0%), major adverse cardiovascular event (MACE; OR: 2.06; 95% CI: 1.39-3.06; I² = 54.0%), and heart failure (OR: 1.99; 95% CI: 1.22-3.24; I² = 0.0%) compared with staged MV-PCI, which were mainly derived from retrospective studies. No differences were observed in myocardial infarction or revascularization. Pooled multivariable adjusted results consistently indicated that staged MV-PCI was superior to culprit-only PCI.

CONCLUSIONS

For patients with STEMI accompanied by CTO in the non-IRA, staged MV-PCI may be better compared with culprit-only PCI due to potential reduced risks of all-cause mortality, cardiac death, stroke, MACE, and heart failure. Meanwhile, further randomized trials are warranted to confirm or refute our findings.

The constricting effect of reduced coronary artery compliance on the left ventricle is an important cause of reduced diastolic function in patients with coronary heart disease

Background

Previous studies of left ventricular diastolic function (LVDF) have focused on the decrease in active and passive diastolic function due to ischemic factors but have not investigated if the decrease in compliance of the coronary arteries that bypass the surface of the heart and travel between the myocardium could cause a constricting effect on the ventricular wall like that caused by myocardial fibrosis.

Methods and Results

581 patients diagnosed with coronary heart disease (CHD) were divided into A group (patients are the control group), B group (patients with less than 50% coronary artery stenosis), C group (patients with coronary artery stenosis between 50 and 75%), D group (patients with coronary artery stenosis greater than 75%) according to the degree of coronary stenosis. The diastolic function of the ventricle is reflected by applying the relaxation time constant T value, which refers to the time between peak dp/dt and end-diastolic pressure in the left ventricle. It was concluded that there was a statistical difference in Gensini scores between patients in groups B, C and D (P < 0.001). And multiple linear regression analysis showed that T was correlated with Gensini score and C-dp/dtmax (R = 0.711, P < 0.001). Grouping according to the site of stent implantation and the number of stents implanted, it was found out that the changes in T values before and after left anterior descending artery (LAD) stent implantation were greater than left circumflex artery (LCX) and right coronary artery (RCA) (P < 0.001). And multiple linear regression revealed a correlation between T values and stent length, ventricular stiffness, and C-dp/dtmax (P = 0.001).

Conclusions

The decrease in compliance of the coronary arteries bypassing the surface of the heart and travelling between the myocardium would cause a constricting effect on the ventricular wall like that caused by myocardial fibrosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02809-0.

Comparison of Outcomes of Patients With Acute Myocardial Infarction Between Chronic Total Occlusion Versus 90-99% Stenosis in Non-Culprit Arteries

Patients with acute myocardial infarction (AMI) with chronic total occlusion (CTO) in nonculprit arteries had worse prognosis than patients with AMI without CTO in nonculprit arteries. However, the reason was not clearly explained. This retrospective study aimed to compare the clinical outcomes between patients with AMI with CTO versus those with severe stenosis (90% to 99% stenosis) in nonculprit arteries, which would help to elucidate the role of CTO in nonculprit arteries. We included 643 patients with AMI and divided those into the CTO group (n = 188) and 90% to 99% stenosis group (n = 455). The primary end point was the major adverse cardiovascular events (MACE) defined as the composite of all-cause death, nonfatal myocardial infarction, and readmission for heart failure. During the median follow-up duration of 431 days (Q1:178 days to Q3:950 days), a total of 189 MACE was observed. The Kaplan-Meier curves showed that MACE was more frequently observed in the CTO group than in the 90% to 99% stenosis group (p <0.001). The multivariate Cox hazard analysis revealed that CTO in nonculprit arteries (vs 90% to 99% stenosis) was significantly associated with MACE (hazard ratio 1.410, 95% confidence interval 1.042 to 1.907; p = 0.026) after controlling known confounding factors. In conclusion, patients with AMI with CTO in nonculprit arteries had worse clinical outcomes than those with 90% to 99% stenosis in nonculprit arteries. Patients with AMI with CTO could be recognized as a high-risk group rather than those with 90% to 99% stenosis and should be carefully managed to prevent cardiovascular events.

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.

Risk Factor Analysis and Construction of a Prognostic Model after Percutaneous Coronary Intervention in Patients with Chronic Total Occlusion

METHODS

The clinical data of 82 patients with CTO who underwent PCI in Lianshui County People's Hospital were collected in this study. The patients were divided into training set (n = 54) and validation set (n = 28) by random sampling method. Statistical difference test was performed for clinical features of patients. Univariate and multivariate Cox regression analyses were performed to determine the risk factors affecting progression of CTO. Nomogram was used to construct a prediction model for disease progression. C-index was calculated, and the accuracy of the model was tested by calibration curve.

RESULTS

No statistically significant differences were incorporated in baseline characteristics of included patients (p > 0.05). There were 25 patients with adverse cardiac events during follow-up in the training set and 13 in the validation set. The results of multivariate Cox regression analysis demonstrated that the important factors affecting postoperative disease progression mainly came down to age, BMI, diabetes, creatinine clearance rate, and left ventricular fraction < 40%. A nomogram was constructed and C-index was calculated. The calibration curve was then used to evaluate and predict risk model of disease progression. The result showed an internal validation C-index of 0.6219 and an external validation C-index of 0.6453, which indicated the good prediction performance of the model.

CONCLUSION

The risk of disease progression in CTO patients treated with PCI can be effectively predicted by the risk model constructed in this study, which opens up a great possibility for enriching the means of predicting the prognosis of these patients in clinical practice.

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

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

Update on chronic total occlusion percutaneous coronary intervention

Chronic total occlusion (CTO) percutaneous coronary interventions (PCI) can be challenging to perform. The main indication for CTO PCI is to improve symptoms. Several contemporary studies have reported high CTO PCI success rates at experienced centers but success rates in all-comer registries remain low. Several scores can estimate the difficulty and the likelihood of success of CTO PCI. Dual arterial access and use of CTO crossing algorithms can improve the success and safety of CTO PCI. Intracoronary imaging can optimize stent expansion and minimize adverse cardiovascular events. While complications are more common in CTO PCI, careful planning and prompt diagnosis and treatment can prevent them or minimize their adverse consequences. In this article, we review contemporary data on the indications, safety and efficacy of CTO PCI.

The effect of slow breathing exercise on heart rate and blood pressure in patients undergoing percutaneous coronary intervention: a randomized controlled trial

AIM

To determine the effects of slow breathing exercise (SBE) on heart rate (HR) and blood pressure (BP) in patients after percutaneous coronary intervention (PCI).

METHODS AND RESULTS

The study is a single-blind, randomized controlled trial. Seventy-eight eligible patients after primary PCI were divided randomly into either the control group or the trial group. The control group only received routine post-PCI care. In addition to routine care, participants in the trial group performed SBE at home, two to three times for a total of 30 min every day for 12 weeks. The main outcomes were HR and BP measured in the office and at home. The secondary outcome was compliance with the breathing exercise. Patients allocated to the trial group, on average, performed 5.21 days/week for 26.00 min/day. The trial group showed a significant reduction in HR of 3.95 b.p.m. (P = 0.004) measured in the office. The reduction in HR measured in the office was greater for the trial group, with a significant difference between the two groups (P = 0.005). There was no significant difference between the two groups in HR measured at home. There was also no significant difference in BP measured in the office or at home between the two groups.

CONCLUSION

Slow breathing exercise is an effective non-pharmacological method to reduce HR in patients undergoing PCI. Further study is needed to confirm whether the intervention is effective on BP.

Does multivessel revascularization fit all patients with STEMI and multivessel coronary artery disease? A systematic review and meta-analysis

Objective

We sought to assess the relative merits of different revascularization strategies in patients with ST-segment elevation myocardial infarction (STEMI) and multivessel coronary artery disease complicated by cardiogenic shock or chronic total occlusion (CTO).

Background

Recent randomized trials and meta-analysis have suggested that multivessel percutaneous coronary intervention (PCI) is associated with better outcomes in patients with STEMI and multivessel coronary artery disease, however, patients complicated by cardiogenic shock or CTO were excluded.

Methods

Studies that compared multivessel PCI (immediate or staged) with culprit-only PCI in patients with STEMI and multivessel coronary artery disease complicated by cardiogenic shock or CTO were included. Random odd ratio (OR) and 95% confidence interval (CI) were conducted.

Results

Sixteen studies with 8695 patients complicated by cardiogenic shock and eight studies with 2259 patients complicated by CTO were included. In patients complicated by cardiogenic shock, a strategy of CO-PCI was associated with lower risk for short-term renal failure (OR: 0.75; 95% CI: 0.61–0.93; I² = 0.0%), with no significant difference in MACE, all-cause mortality, re-infarction, revascularization, cardiac death, heart failure, major bleeding, or stroke compared with an immediate MV-PCI strategy. In patients complicated by CTO, a strategy of CO-PCI was associated with higher risk for long-term MACE (OR: 2.06; 95% CI: 1.39–3.06; I² = 54.0%), all-cause mortality (OR: 2.89; 95% CI: 2.09–4.00; I² = 0.0%), cardiac death (OR: 3.12; 95% CI: 2.05–4.75; I² = 16.8%), heart failure (OR: 1.99; 95% CI: 1.22–3.24; I² = 0.0%), and stroke (OR: 2.80; 95% CI: 1.04–7.53; I² = 0.0%) compared with a staged MV-PCI strategy, without any difference in re-infarction, revascularization, or major bleeding.

Conclusions

For patients with STEMI and multivessel coronary artery disease complicated by cardiogenic shock, an immediate multivessel PCI was not advocated due to a higher risk for short-term renal failure, whereas for patients complicated by CTO, a staged multivessel PCI was advocated due to reduced risks for long-term MACE, all-cause mortality, cardiac death, heart failure, and stroke.

Infarct-related chronic total coronary occlusion and the risk of ventricular tachyarrhythmic events in out-of-hospital cardiac arrest survivors

Introduction

Chronic total coronary occlusion (CTO) has been identified as a risk factor for ventricular arrhythmias, especially a CTO in an infarct-related artery (IRA). This study aimed to evaluate the effect of an IRA-CTO on the occurrence of ventricular tachyarrhythmic events (VTEs) in out-of-hospital cardiac arrest survivors without ST-segment elevation.

Methods

We conducted a post hoc analysis of the COACT trial, a multicentre randomised controlled trial. Patients were included when they survived index hospitalisation after cardiac arrest and demonstrated coronary artery disease on coronary angiography. The primary endpoint was the occurrence of a VTE, defined as appropriate implantable cardioverter-defibrillator (ICD) therapy, sustained ventricular tachyarrhythmia or sudden cardiac death.

Results

A total of 163 patients from ten centres were included. Unrevascularised IRA-CTO in a main vessel was present in 43 patients (26%). Overall, 61% of the study population received an ICD for secondary prevention. During a follow-up of 1 year, 12 patients (7.4%) experienced at least one VTE. The cumulative incidence rate of VTEs was higher in patients with an IRA-CTO compared to patients without an IRA-CTO (17.4% vs 5.6%, log-rank p = 0.03). However, multivariable analysis only identified left ventricular ejection fraction < 35% as an independent factor associated with VTEs (adjusted hazard ratio 8.7, 95% confidence interval 2.2–35.4). A subanalysis focusing on CTO, with or without an infarct in the CTO territory, did not change the results.

Conclusion

In out-of-hospital cardiac arrest survivors with coronary artery disease without ST-segment elevation, an IRA-CTO was not an independent factor associated with VTEs in the 1st year after the index event.

Supplementary Information

The online version of this article (10.1007/s12471-021-01578-3) contains supplementary material, which is available to authorized users.

Clinical outcomes of percutaneous coronary intervention for chronic total occlusion in prior coronary artery bypass grafting patients

OBJECTIVE

To compare the clinical characteristics and outcomes in patients with stable angina who have undergone chronic total occlusion (CTO) percutaneous coronary intervention (PCI) in native arteries with or without prior coronary artery bypass grafting (CABG) surgery in a national cohort.

BACKGROUND

There are limited data on outcomes of patients presenting with stable angina undergoing CTO PCI with previous CABG.

METHODS

We identified 20,081 patients with stable angina who underwent CTO PCI between 2007-2014 in the British Cardiovascular Intervention Society database. Clinical, demographical, procedural and outcome data were analyzed in two groups; group 1-CTO PCI in native arteries without prior CABG (n = 16,848), group 2-CTO PCI in native arteries with prior CABG (n = 3,233).

RESULTS

Patients in group 2 were older, had more comorbidities and higher prevalence of severe left ventricular systolic dysfunction. Following multivariable analysis, no significant difference in mortality was observed during index hospital admission (OR:1.33, CI 0.64-2.78, p = .44), at 30-days (OR: 1.28, CI 0.79-2.06, p = .31) and 1 year (OR:1.02, CI 0.87-1.29, p = .87). Odds of in-hospital major adverse cardiovascular events (MACE) (OR:1.01, CI 0.69-1.49, p = .95) and procedural complications (OR:1.02, CI 0.88-1.18, p = .81) were similar between two groups but procedural success rate was lower in group 2 (OR: 0.34, CI 0.31-0.39, p < .001). The adjusted risk of target vessel revascularization (TVR) remained similar between the two groups at 30-days (OR:0.68, CI 0.40-1.16, P-0.16) and at 1 year (OR:1.01, CI 0.83-1.22, P-0.95).

CONCLUSION

Patients with prior CABG presenting with stable angina and treated with CTO PCI in native arteries had more co-morbid illnesses but once these differences were adjusted for, prior CABG did not independently confer additional risk of mortality, MACE or TVR.

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.

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.

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.

Outcomes of Percutaneous Coronary Intervention Versus Optimal Medical Treatment for Chronic Total Occlusion: A Comprehensive Meta-analysis

The presence of concurrent chronic total occlusion (CTO) is a strong predictor for both short-term and long-term mortality. Successful percutaneous coronary intervention (PCI) of CTO has been associated with clinical benefit. We sought to perform a meta-analysis comparing CTO-PCI versus optimal medical therapy. PubMed, ClinicalTrials.gov, Google scholar and the Cochrane Central Register of Controlled Trials were searched for studies published from 2006 to 2019. A total of 16 studies, with 11,314 patients were included. We analyzed data on mortality, cardiac deaths, myocardial re-infarction, major adverse cardiac events, stroke, and repeat CTO-PCI using random-effects models. The odds ratios (OR) with 95% confidence interval (CI) were computed and P < 0.05 was considered as a level of significance. Compared with medical therapy alone, CTO-PCI was associated with lower mortality (OR: 0.45, CI: 0.32-0.63, P < 0.00001) and cardiac deaths (OR: 0.58, CI: 0.38-0.89, P = 0.01). These results were primarily driven by observational studies with no difference observed in randomized controlled trials. There was no significant difference in the incidence of major adverse cardiac events (OR: 0.71, CI: 0.48-1.05, P = 0.54), myocardial re-infarction (OR: 0.71, CI: 0.48-1.05, P = 0.54), stroke (OR: 0.61, CI: 0.32-1.17, P = 0.14, and repeat PCI (OR: 1.28, CI: 0.91-1.78, P = 0.16). This meta-analysis shows lower long-term mortality and cardiac deaths in CTO-PCI group as compared to OMT driven by observational studies with no difference observed in randomized controlled trials. Further randomized trials are needed to confirm these findings and evaluate long term results.

Non-pharmacological Treatment of Refractory Angina and Microvascular Angina

Refractory angina (RA) is defined as debilitating anginal symptoms despite the optimal guideline-directed combination of medical, percutaneous, and surgical therapies. Often referred to as “no option”, these patients represent a significant unmet clinical need for healthcare institutions. Due to the ageing of the population, and increased survival from coronary artery disease, the number of patients with RA is expected to rise exponentially. Despite the developments of novel technologies for the treatment of RA, none of them found wide clinical application (to date). Microvascular dysfunction, alone or in combination with epicardial coronary disease, is thought to contribute significantly to refractory angina. However, most of the techniques developed to improve RA symptoms have not been tested specifically on patients with microvascular dysfunction. This review discusses the recent developments in the treatment of RA, and gives some perspectives on the future of these techniques.

The role of coronary angiography in out-of-hospital cardiac arrest patients in the absence of ST-segment elevation: A literature review

Out-of-hospital cardiac arrest (OHCA) is a major cause of death. Although the aetiology of cardiac arrest can be diverse, the most common cause is ischaemic heart disease. Coronary angiography and percutaneous coronary intervention, if indicated, has been associated with improved long-term survival for patients with initial shockable rhythm. However, in patients without ST-segment elevation on the post-resuscitation electrocardiogram, the optimal timing of performing this invasive procedure is uncertain. One important challenge that clinicians face is to appropriately select patients that will benefit from immediate coronary angiography, yet avoid unnecessary delay of intensive care support and targeted temperature management. Observational studies have reported contradictory results and until recently, randomised trials were lacking. The Coronary Angiography after Cardiac Arrest without ST-segment elevation (COACT) was the first randomised trial that provided comparative information between coronary angiography treatment strategies. This literature review will provide the current knowledge and gaps in the literature regarding optimal care for patients successfully resuscitated from OHCA in the absence of ST-segment elevation and will primarily focus on the role and timing of coronary angiography in this high-risk patient population.

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.

Periprocedural and clinical outcomes of percutaneous coronary intervention of chronic total occlusions in patients with low- and mid-range ejection fractions

BACKGROUND

The benefit and safety of percutaneous coronary intervention (PCI) to chronic total occlusions (CTO) in patients with low and mid-range left ventricular ejection fraction (LVEF) continue to be evidence limited. The aim of our study was to investigate the impact of LVEF in patients undergoing CTO PCI and to evaluate the mid-term clinical outcome of those with low and mid-range LVEF. We assessed the periprocedural and mid-term outcomes of 75 patients undergoing CTO PCIs according to pre-procedural LVEF: group (N), ≥ 50% (normal, nom.= 25); group (M), 40-49% (mid-range, nom.= 25); and group (L), < 40% (low, nom.= 25); within 6 months of follow-up.

RESULTS

The prevalence of DM and chronic kidney disease (CKD) was significantly higher in low LVEF group (60%, p = 0.04 and 48%, p = 0.01 respectively). Apart from significantly lower contrast volume in patients with low LVEF (p = 0.04), there was no significant difference between the three groups regarding the procedural time, SYNTAX score and J-CTO score. We noticed similar procedural success in the three groups (88% vs. 84% vs. 76%, p = 0.521). LVEF category failed to predict procedural success (OR = 0.652, p = 0.268). There was a highly significant improvement in angina 6 months following intervention in normal LVEF group (p value < 0.001). Grade of dyspnea significantly improved 6 months following intervention in mid-range LVEF and low LVEF groups (p value = 0.04 and 0.031 respectively). There was no significant difference between the three groups regarding the reported MACCEs (12% vs. 16% vs. 28%, p = 0.268).

CONCLUSION

CTO PCI represents an efficient and safe strategy in patients with low and mid-range LVEFs. Mid-term outcomes in these patients were significantly improved following successful CTO PCI, without higher risk of MACCE at 6 months follow-up.

The success of opening concurrent chronic total occlusion lesion to improve cardiac function trial in patients with multi-vessel disease (SOS-moral): Study protocol of a prospective multicenter study

AIMS

The purpose of the present trial is to determine whether opening co-existing chronic total occlusions (CTOs) using percutaneous coronary interventions (PCIs) improves cardiac function in patients with multi-vessel disease (MVD). Patients with MVD are defined as having at least one additional major vessel exhibiting no less than 75% stenosis combined with the presence of a CTO artery.

METHODS AND RESULTS

Patients will be prospectively recruited who meet the following criteria:Patients presenting with no necrosis of myocardial tissue in the territory of the CTO will be excluded. Recruited patients will be randomized into 2 groups: those undergoing PCI of only the non-CTO artery (non-CTO PCI group), and those undergoing PCI of the non-CTO artery concurrently with the CTO artery (CTO-PCI group). The primary outcome will be the change in cardiac function evaluated via CMR at a 12-month of follow-up appointment, which will be compared to a baseline measurement. Secondary outcomes include occurrence of major cardiac events, CMR-assessed myocardial viability in the CTO-supplied territory, and quality of life assessed by Seattle angina questionnaire, Patient Health Questionnaire 9 and Generalized Anxiety Disorder Scale-7 after 12-month follow-up.

CONCLUSION

The SOS-moral trial will provide data necessary to determine whether to open concurrent CTOs among MVD patients with CMR-detected necrotic myocardial tissue.

The Role of Percutaneous Coronary Intervention in the Treatment of Chronic Total Occlusions: Rationale and Review of the Literature

BACKGROUND

Chronic total occlusion (CTO) of a coronary artery is defined as an occluded segment with no antegrade flow and a known or estimated duration of at least 12 weeks.

OBJECTIVE

We considered the current literature describing the indications and clinical outcomes for denovo CTO- percutaneous coronary intervention (PCI), and discuss the role of CTO-PCI and future directions for this procedure.

METHODS

Databases (PubMed, the Cochrane Library, Embase, EBSCO, Web of Science, and CINAHL were searched and relevant studies of CTO-PCI were selected for review.

RESULTS

The prevalence of coronary artery CTO's has been reported to be ~ 20% among patients undergoing diagnostic coronary angiography for suspected coronary artery disease. Revascularization of any CTO can be technically challenging and a time-consuming procedure with relatively low success rates and may be associated with a higher incidence of complications, particularly at non-specialized centers. However, with an increase in experience and technological advances, several centers are now reporting success rates above 80% for these lesions. There is marked variability among studies in reporting outcomes for CTO-PCI with some reporting potential mortality benefit, better quality of life and improved cardiac function parameters. Anecdotally, properly selected patients who undergo a successful CTO-PCI most often have profound relief of ischemic symptoms. Intuitively, it makes sense to revascularize an occluded coronary artery with the goal of improving cardiovascular function and patient quality of life.

CONCLUSION

CTO-PCI is a rapidly expanding specialized procedure in interventional cardiology and is reasonable or indicated if the occluded vessel is responsible for symptoms or in selected patients with silent ischemia in whom there is a large amount of myocardium at risk and PCI is likely to be successful.

Impact of coronary collateralization on long-term clinical outcomes in type 2 diabetic patients after successful recanalization of chronic total occlusion

Background

To assess the prognostic role of coronary collaterals in patients with type 2 diabetes mellitus (T2DM) after successful percutaneous coronary intervention (PCI) for chronic total occlusion (CTO).

Methods

Coronary collateralization was graded according to Rentrop scoring system in 198 type 2 diabetic patients and 335 non-diabetics with stable angina undergoing PCI for at least one CTO lesion. Left ventricular ejection fraction (LVEF) was determined and major adverse cardio-cerebral events (MACCE) were recorded during follow-up.

Results

Poor collateralization was more common in patients with T2DM than in non-diabetics (40% vs 29%, p = 0.008). At 13.5 ± 4.1 months, the rate of composite MACCE (17.3% vs 27.6%, p = 0.034) and repeat revascularization (15.2% vs 25.5%, p = 0.026) was lower and the increase in LVEF (3.10% vs 1.80%, p = 0.024) was greater in patients with good collaterals than in those with poor collaterals for non-diabetic group. The associations were in the same direction for T2DM group (35% vs 44%; 30% vs 36%; 2.14% vs 1.65%, respectively) with a higher all-cause mortality in diabetic patients with poor collaterals (p = 0.034). Multivariable Cox proportional hazards analysis showed that coronary collateralization was an independent factor for time to MACCE (HR 2.155,95% CI 1.290–3.599, p = 0.003) and repeat revascularization (HR 2.326, 95% CI 1.357–3.986, p = 0.002) in non-diabetic patients, but did not enter the model in those with T2DM.

Conclusions

T2DM is associated with reduced coronary collateralization. The effects of the status of coronary collateralization on long-term clinical outcomes and left ventricular function appear to be similar in size in type 2 diabetic patients and non-diabetics after successful recanalization of CTO.

Long-term clinical effects of recanalization of chronic coronary total occlusions in patients with left ventricular systolic dysfunction

OBJECTIVES

The aim of the present analysis is to evaluate the clinical impact of chronic total occlusions (CTOs) recanalization in patients with left ventricular (LV) systolic dysfunction.

BACKGROUND

According to contemporary knowledge, patient selection for percutaneous CTO revascularization is not yet standardized. In particular, data on outcomes in patients with LV systolic dysfunction undergoing percutaneous coronary intervention (PCI) for CTO are scarce.

METHODS

From a total of 2,421 consecutive patients with at least one CTO, 436 patients with ejection fraction (EF) ≤45%, who were referred for coronary angiography between January 1998 and September 2014, were selected. Patients with successful recanalization of the target CTO were assigned to CTO-revascularized group and those with failed or not attempted recanalization to the CTO-not revascularized (CTO-NR) group. Study endpoints were all-cause death, cardiac death, and occurrence of myocardial infarction on follow-up.

RESULTS

Out of 436 CTO patients with reduced EF, 228 (52.3%) were successfully recanalized and 208 patients (47.7%) were not, either due to CTO-PCI failure (n = 106, 24.3%) or because CTO-PCI was not attempted (n = 102, 23.4%). At long-term follow-up, CTO-NR patients had significantly higher rate of overall (p = .021) and cardiac mortality (p = .035) compared to those successfully revascularized.

CONCLUSION

In patients with systolic LV dysfunction (EF ≤ 45%), CTO revascularization was associated with significant lower rate of total and cardiac mortality compared to those with nonrevascularized CTO.

Efficacy and safety of standard and low dose ticagrelor versus clopidogrel in east AsianPatients with chronic total occlusion undergoing percutaneous coronary intervention: a single center retrospective study

BACKGROUND

Patients with coronary chronic total occlusion (CTO) require effective antiplatelet therapy after percutaneous coronary intervention (PCI). Ticagrelor has more pronounced platelet inhibition than clopidogrel. However, the most appropriate dose of ticagrelor in East Asian populations remains unclear.

METHOD

We compared ticagrelor (180 mg loading dose, 90 mg twice daily thereafter and 120 mg loading dose, 60 mg twice daily thereafter) and clopidogrel (300 mg loading dose, 75 mg daily thereafter) for prevention of cardiovascular events in 525patients with CTO undergoing PCI.

RESULTS

The rate of in-hospital major adverse cardiac and cerebral events (MACCE) was not different between the groups. At 1-year follow-up, target vessel revascularization (TVR) in both ticagrelor groups were significantly lower than that in the clopidogrel group (p = 0.047); TVR was significantly decreased in 60 mg ticagrelor compared to standard dose clopidogrel (p = 0.046). At 1-year follow-up, overall MACCE in both ticagrelor groups were significantly lower than that in the clopidogrel group (p = 0.023). Kaplan-Meier analysis showed MACCE-free survival was significantly higher in both ticagrelor groups than in the clopidogrel group (p = 0.024). During hospitalization, minor bleeding was significant increased in the 90 mg ticagrelor group (p = 0.021). At 1-year follow-up, risk of major and minor bleeding were significantly increased in the 90 mg ticagrelor group.

CONCLUSION

In East Asian patients with CTO undergoing PCI, 60 mg ticagrelor was as effective as 90 mg, at the same time significantly reduced risk of bleeding.

Incidence, Predictors, and Prognosis of Coronary Slow-Flow and No-Reflow Phenomenon in Patients with Chronic Total Occlusion Who Underwent Percutaneous Coronary Intervention

Background

The incidence and prognosis of coronary slow-flow (CSF) and no-reflow phenomenon (NRP) in patients with coronary chronic total occlusion (CTO) who underwent percutaneous coronary intervention (PCI) remain unclear.

Methods

This single-center prospective study aimed to investigate the incidence of CSF/NRP during CTO interventional therapy, determine predictors of CSF/NRP, and evaluate its effect on patient outcomes.

Results

In this study, 552 patients with CTO who underwent PCI were included. CSF/NRP occurred in 16.1% of them. They had higher incidences of diabetes mellitus (53.9% vs 36.3%, p=0.002) and hypertension (50.6% vs 37.1%, p=0.018) and a lower incidence of retrograde filling grade >2 (34.8% vs 47.1%, p=0.036). Patients with CSF/NRP had a higher neutrophil ratio (55.6±19.4 vs 52.4±18.3, p=0.038) and levels of low-density lipoprotein (LDL; 3.0±0.8 vs 2.8±0.6, p=0.029), fasting glucose (FG; 8.3±1.3 vs 6.8±1.1, p=0.005), uric acid (332.6±82.9 vs 308.2±62.8, p=0.045), and high-sensitivity C-reactive protein (Hs-CRP; 9.8±4.8 vs 7.3±3.9, p=0.036). A multivariate logistic regression analysis revealed that diabetes mellitus (odds ratio [OR], 1.962; 95% confidence interval [CI]: 1.198–2.721; p=0.042), mean platelet volume (MPV; OR,1.284; 95% CI, 1.108–1.895; p=0.046), LDL cholesterol (LDL-C; OR, 1.383; 95% CI, 1.105–2.491; p=0.036), FG (OR, 2.095; 95% CI, 1.495–2.899; p=0.018), Hs-CRP(OR, 2.218; 95% CI, 1.556–3.519; p=0.029), and retrograde filling of grade >2 (OR, 0.822; 95% CI, 0.622–0.907; p=0.037) were independent predictors of CSF/NRP in CTO patients who underwent PCI. Kaplan-Meier analysis revealed that the patients in the CSF/NRP group had a significantly lower cumulative major cardiac and cerebrovascular events (MACCE)-free survival than those in the non-CSF/NRP group (p<0.0001).

Conclusion

Of the patients with CTO who underwent PCI, 16.1% developed CSF/NRP and had a significantly lower cumulative MACCE-free survival rate. Diabetes mellitus; higher levels of MPV, LDL-C, FG, and Hs-CRP; and a lower incidence of retrograde filling grade >2 were independent predictors of CSF/NRP in CTO patients who underwent PCI. Thus, they can be used for risk stratification.

Echocardiographic assessment of left ventricular function recovery post percutaneous coronary intervention of chronic total occlusions in patients with low and mid-range left ventricular ejection fractions

OBJECTIVES

Coronary chronic total occlusion (CTO) is a frequent condition encountered in cardiac catheterization laboratory with a prevalence of about 20%. Through literature, data are scarcely reported regarding the left ventricular (LV) function recovery post CTO percutaneous coronary intervention (PCI) in patients with low (<40%) and mid-range (40%-49%) LV ejection fraction (LVEF). The aim of this study was to assess the echocardiographic outcomes of CTO patients with low and mid-range LVEF successfully revascularized at 6-month follow-up.

METHODS

This prospective study included 75 patients with at least one CTO of an epicardial coronary artery proved by previous diagnostic coronary angiography with PCI attempt indication, and successfully revascularized. They were equally divided according to LVEF into three groups, and echocardiographic remodeling indices were assessed at baseline and 6 months post PCI.

RESULTS

Our study showed significant improvement of LVEF, S-wave velocity by tissue doppler imaging (TDI), LV wall-motion score (LVWMS), and LV systolic sphericity index (LVSIS) 6 months post CTO PCI in low LVEF group, and a significant improvement in LVEF, S-wave velocity, and LVWMS in mid-range LVEF group (P < .05). The delta change in LVEF was significantly more in low LVEF group, compared to the other two groups (F = 4.739, P < .05).

CONCLUSION

Successful CTO PCI in patients with low and mid-range LVEF is associated with significant improvement of LVEF and other indices of myocardial remodeling after 6 months of follow-up.

Impact of Elevated Serum Uric Acid Level on Target Lesion Revascularization After Percutaneous Coronary Intervention for Chronic Total Occlusion

Elevated serum uric acid (SUA) level is reportedly associated with subsequent cardiovascular events including revascularization in patients with coronary artery disease. However, the impact of SUA level on revascularization in patients with chronic total occlusion (CTO), one of the highest risk subsets in coronary artery disease, is unclear. The aim of this study was to evaluate the impact of SUA level on target lesion revascularization (TLR) in contemporary percutaneous coronary intervention (PCI) for CTO. A total of 165 patients who underwent successful PCI with new-generation drug-eluting stent for CTO under intravascular ultrasound guidance were included. Patients were classified into 3 groups according to the tertiles of SUA level at baseline. Coronary angiography was qualitatively and quantitatively assessed, and gray-scale intravascular ultrasound was also analyzed. The primary end point was TLR. The tertiles of SUA level were as follows: low tertile, ≤5.2 mg/dl; intermediate tertile, 5.3 to 6.4 mg/dl; and high tertile, ≥6.5 mg/dl. During a median follow-up of 34 months, TLR was observed in 5 patients (8.8%) in the low tertile, in 5 (9.4%) in the intermediate tertile, and in 14 (25.5%) in the high tertile (p = 0.02). Kaplan-Meier analysis demonstrated a significantly higher incidence of TLR in patients with high tertile than the low and intermediate groups. Multivariable analysis showed SUA ≥6.5 mg/dl, diabetes mellitus, and longer CTO length as independent predictors of TLR. In conclusion, in patients who underwent PCI with drug-eluting stent, elevated SUA level was associated with TLR after successful recanalization of CTO.

Incidence and characteristics of ventricular tachycardia in patients after percutaneous coronary revascularization of chronic total occlusions

Objectives

This study sought to investigate the prevalence of ventricular tachycardia after percutaneous coronary intervention (PCI) of chronic total occlusion (CTO).

Background

PCI of a CTO is associated with improvement of the left ventricular ejection fraction and possibly associated with reduced mortality. However, benefits of CTO-PCI must be weighed against a higher risk of procedure-related complications. The incidence of new-onset ventricular tachycardia after a successful CTO-PCI has not been investigated so far. In this retrospective registry we seek to describe characteristics and predictors of occurrence of post-procedural ventricular tachycardias.

Methods and results

Between 2010 and 2015, 485 patients underwent successful CTO-PCI at Heart Center Leipzig. Of them, 342 had complete follow-up and were further analyzed. Ventricular tachycardias were detected in 9 (2.6%) patients. All of them were monomorphic ventricular tachycardias occurring in median 1 day (interquartile range [IQR] 0.25–4.75 days) after PCI and caused prolongation of the hospital stay. Patients with ventricular tachycardia were older, had worse left ventricular ejection fraction (mean 33.1%, SD 5.9%) and more frequently a CTO of an infarct-related artery. The target vessel was not associated with the occurrence of ventricular arrhythmias. In multivariable analysis, only impaired left ventricular systolic function was an independent predictor for procedure-related ventricular tachycardia. Mortality rates were not different between patients with or without ventricular tachycardia.

Conclusion

Ventricular tachycardia can occur early after CTO-PCI as possible reperfusion arrhythmia and poorer left ventricular ejection fraction is the only independent predictor for onset. Although the occurrence of ventricular tachycardia after CTO-PCI seems not to influence mortality, awareness of this possible complication and longer monitoring may be recommended.

Outcomes after percutaneous coronary intervention and comparison among scoring systems in predicting procedural success in elderly patients (≥ 75 years) with chronic total occlusion

BACKGROUND

Evidence-based data on percutaneous coronary intervention in elderly patients with chronic total occlusion (CTO) and comparison among different scoring systems have not been well established.

PATIENTS AND METHODS

A total of 246 consecutive patients were stratified into two groups according to the age: elderly group (age≥ 75 years, n = 68) and nonelderly group (age < 75 years, n = 178). Clinical and angiographic characteristics including the Synergy Between PCI With TAXUS and Cardiac Surgery score, in-hospital major adverse cardiac events, procedural success rates, and predictive capacity of four scoring systems [J-CTO, Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS CTO), clinical and lesion-related (CL), and ostial location, Rentrop grade < 2, age ≥ 75 years (ORA) scores] were examined.

RESULTS

Triple-vessel disease and the Synergy Between PCI With TAXUS and Cardiac Surgery score in the elderly group were significantly higher than those in the nonelderly group (73.53 vs. 53.93%, P = 0.005; 31.39 ± 7.68 vs. 27.85 ± 7.16, P = 0.001, respectively). The in-hospital major adverse cardiac event rates, vascular access complication rates, and major bleeding rates were similar between the elderly and the nonelderly group (2.94 vs. 2.25%, P = 0.669; 1.47 vs. 0.56%, P = 0.477; 2.94 vs. 1.12%, P = 0.306, respectively). By contrast, the procedural success rate was statistically lower in the elderly group than that in the nonelderly group (73.53 vs. 84.83%, P = 0.040). All the four scoring systems showed a moderate predictive capacity [area under the curve (AUC) for J-CTO score: 0.806, P < 0.0001; AUC for PROGRESS CTO score: 0.727, P < 0.0001; AUC for CL score: 0.800, P < 0.0001; AUC for ORA score: 0.672, P < 0.0001, respectively]. Compared with the ORA score, the J-CTO score, and the CL score showed a significant advantage in predicting procedural success among overall patients (ΔAUC = 0.134, P = 0.0122; ΔAUC = 0.128, P = 0.0233, respectively).

CONCLUSION

Despite the lower procedural success rate, percutaneous coronary intervention in elderly patients with CTO is feasible and safe. J-CTO, PROGRESS, ORA, and CL scoring systems have moderate discriminatory capacity.

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.

Evaluation of the impact of percutaneous coronary intervention of chronic total occlusion on regional myocardial function using strain echocardiography

BACKGROUND

Successful revascularization of chronic total occlusions has been associated with potential effects on left ventricular (LV) function. Strain and strain rate are more sensitive measures of LV mechanics than LV ejection fraction (LVEF). This study was conducted to investigate the impact of revascularization of chronic total occlusion (CTO) on LV function using tissue Doppler (TDI) strain echocardiography.

RESULTS

This study included 60 patients divided into two main groups: the percutaneous coronary intervention (PCI) group including patients who had a successful PCI of CTO on left anterior descending (LAD) artery and was presented for elective PCI with symptomatic angina and/or positive functional ischemic study. They included 18 males with a mean age of 57 ± 5 years. The optimum medical treatment (OMT) group, including 30 patients, had non-revascularized CTO-LAD and was kept on OMT alone; 20 of them were males with a mean age of 58 ± 4 years. In the PCI group, there was a significant improvement in all the TDI strain parameters of the LAD territory segments. Six months after PCI, the peak systolic strain rate improved from - 0.65 ± 0.21 to 1.05 ± 0.31 1/s (p value < 0.01), the peak systolic strain improved from 6.54 ± 2.48 to 11.51 ± 3.33% ( p value < 0.001 ), and the end systolic strain improved from 7.88 ± 2.77 to 10.51 ± 3.14% (p value < 0.01 ). There was no significant improvement in the mean LVEF (60.70 ± 8.33 vs 61.91 ± 8.16% (p value = 0.6)). In the OMT group, there was no improvement in all the strain parameters and there was no change in the mean LVEF. In the PCI group, there was a significant improvement in the angina class (p value = 0.03) while, in the OMT group, there was no significant improvement (p value = 0.835).

CONCLUSIONS

Successful PCI for CTO improved regional LV myocardial function assessed by TDI strain echocardiography. This improvement was associated with improvement in the angina class.

Percutaneous Coronary Intervention With Drug-Eluting Stent Versus Optimal Medical Therapy for Chronic Total Occlusion: Systematic Review and Meta-Analysis

The optimal treatment strategy for coronary chronic total occlusion (CTO) has not been well established. The benefit of percutaneous coronary intervention (PCI) was inferred mainly from observational studies comparing successful versus failed PCI without a control group receiving optimal medical therapy (OMT). We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) and observational studies comparing PCI using drug-eluting stent (DES) versus OMT alone in patients with CTO. Eight studies were identified: 3 RCTs and 5 observational studies. Among a total of 4784 included patients, 2461 patients underwent PCI and 2323 patients received OMT. There was a significant association between PCI and lower cardiac mortality (odds ratio = 0.62; 95% confidence interval 0.42-0.93; P = .02). There was no significant difference between PCI and OMT regarding major adverse cardiac events, recurrent myocardial infarction (MI), repeat revascularization, or stroke. In the RCT subset (1399 patients), there was no significant difference between PCI and OMT regarding clinical outcomes. Compared with OMT alone, PCI with DES for CTO was associated with lower cardiac mortality, mainly driven by observational studies, without significant difference in recurrent MI or repeated revascularization. Further RCTs are needed to investigate the role of PCI for management of patients with CTO.