Comparison of Benefit of Successful Percutaneous Coronary Intervention for Chronic Total Occlusion in Patients With Versus Without Reduced (≤40%) Left Ventricular Ejection Fraction

In-Hospital Outcomes Following Surgical Revascularization of Chronic Total Coronary Occlusions

Background and Objectives: Patients with chronic total occlusions of the coronary arteries are either treated with PCI or referred for surgical revascularization. We analyzed the patients with chronic occluded coronary arteries that were surgically treated and aimed to describe the anatomical characteristics, revascularization rates, and in-hospital outcomes achieved with coronary artery bypass grafting. Methods: Angiographic data of 2005 patients with coronary artery disease treated in our institution between January 2005 and December 2014 were retrospectively analyzed. A total of 1111 patients with at least one coronary total occlusion were identified. We reviewed the preoperative coronary angiograms and surgical protocols to determine the presence, localization, and revascularization of coronary occlusions. We also evaluated the perioperative data and in-hospital outcomes. Results: The median age of the study population was 68 years (25th-75th percentiles, 61.0-74.0). Three-vessel disease was present in 94.8% of patients and the rest (5.8%) had a two-vessel disease. The localizations of the occlusions were as follows: 68.4% in the RCA system, 26.4% in the LAD, and 28.5% in the LCX system. Multiple occlusions were present in 22.6% of the patients. Complete coronary total occlusion revascularization was achieved in 86.1% of the patients. The overall in-hospital mortality was 2.3%. The median in-hospital stay was 14.0 days. After logistic regression analysis, age (odds ratio 3.44 [95% confidence interval, 1.81-6.53], p < 0.001, for a 10-year increase) and the presence of peripheral artery disease (odds ratio 3.32 [1.39-7.93], p = 0.007) were the only statistically significant independent predictors of in-hospital mortality. Conclusions: A high revascularization rate and favorable in-hospital outcomes are achieved with coronary artery bypass surgery in patients with multi-vessel diseases and coronary total occlusions. Older age and the presence of peripheral artery disease are independent predictors of in-hospital mortality. A long-term follow-up and the type of graft (arterial vs. venous) used would bring more useful data for this type of revascularization.

Safety and Long-Term Outcomes of Rotablation in Patients with Reduced (<50%) Left Ventricular Ejection Fraction (rEF) (The Rota-REF Study)

Clinical outcomes in patients with reduced left ventricular systolic function undergoing rotational atherectomy (RA) for percutaneous coronary intervention (PCI) remain understudied. Our study sought to evaluate the impact of RA-PCI in patients with LV systolic dysfunction on long-term outcomes. Between 2015 and 2019, 4941 patients with reduced LV function (rEF) undergoing PCI (with or without RA) were included in the hospital database. The primary endpoint was in-hospital major adverse cardiovascular and cerebral events (MACCE). The secondary endpoint was 3-year MACCE. In-hospital MACCE rates were significantly higher in RA-PCI compared to standard PCI without RA (PCI) (7.6% vs. 3.9%, p = 0.0009). However, 3-years MACCE rates were similar in RA-PCI and PCI (26.40% vs. 26.6%, p = 0.948). In conclusion, RA-PCI in patients with rEF is feasible, safe, and shows similar long-term results to PCI.

Association of ejection fraction with mortality and cardiovascular events in patients with coronary artery disease

AIMS

Recent studies suggested that both left ventricular ejection fraction (LVEF) lower than 60% or higher than 65% were associated with an increased mortality in the general population. Uncertainty remains regarding adverse outcomes across LVEF in coronary artery disease (CAD). The common understanding was that LVEF <40% was associated with an increased risk of mortality. But the threshold at LVEF of 40% was arbitrary because quite a lot of adverse outcomes existed in patients with ejection fraction >40%. We aimed to evaluate the relationship between LVEF and mortality or adverse events in CAD patients undergoing percutaneous coronary intervention (PCI).

METHODS AND RESULTS

A total of 10 252 CAD patients undergoing PCI from an observational cohort were studied. All-cause mortality and major adverse cardiovascular and cerebrovascular events (MACCE) were set as outcomes. Kaplan-Meier curves, adjusted Cox regression models, and restricted cubic spline analyses were used for evaluation. A total of 137 (1.3%) patients had all-cause mortality, and 816 (8.0%) patients had MACCE during a median of 2.4 years of follow-up. The median LVEF was 64%. All-cause mortality and MACCE rates changed substantially across LVEF categories, and a linear inverse relationship of LVEF with all-cause mortality and MACCE risk was observed. All-cause mortality or MACCE risk increased significantly below an LVEF of 55 or 65%, respectively. Patients with LVEF <55% had a more than 3.5-fold higher mortality than those with LVEF ≥55%. Patients with LVEF <65% had a more than 1.3-fold higher MACCE than those with LVEF ≥65%. Below 55 or 65%, there was a rise in mortality or MACCE. A gradient-response relationship was observed, with an all-cause mortality risk range between 8.6-fold and 3.0-fold increase from LVEF <40 to 50-54.9% and MACCE risk range between 2.4-fold and 1.4-fold from LVEF <40 to 60-64.9%.

CONCLUSIONS

In CAD patients undergoing PCI, LVEF lower than 55% or LVEF lower than 65% was correlated with increased all-cause mortality and MACCE respectively, whereas higher LVEF was not.

Development and Validation of a Novel Nomogram to Predict Improved Left Ventricular Ejection Fraction in Patients With Heart Failure After Successful Percutaneous Coronary Intervention for Chronic Total Occlusion

Background

Heart failure with improved left ventricular ejection fraction (HFiEF) is linked to a good clinical outcome. The purpose of this study was to create an easy-to-use model to predict the occurrence of HFiEF in patients with heart failure (HF), 1 year after successful percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) (CTO PCI).

Methods

Patients diagnosed with HF who successfully underwent CTO PCI between January 2016 and August 2019 were included. To mitigate the effect of residual stenosis on left ventricular (LV) function, we excluded patients with severe residual stenosis, as quantitatively measured by a residual synergy between PCI with Taxus and Cardiac Surgery score (rSS) of &gt;8. We gathered demographic data, medical history, angiographic and procedural characteristics, echocardiographic parameters, laboratory results, and medication information. The least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression models were used to identify predictors of HFiEF 1 year after CTO revascularization. A nomogram was established and validated according to the area under the receiver operating characteristic curve (AUC) and calibration curves. Internal validation was performed using bootstrap resampling.

Results

A total of 465 patients were finally included in this study, and 165 (35.5%) patients experienced HFiEF 1 year after successful CTO PCI. According to the LASSO regression and multivariate logistic regression analyses, four variables were selected for the final prediction model: age [odds ratio (OR): 0.969; 95% confidence interval (CI): 0.952–0.988; p = 0.001], previous myocardial infarction (OR: 0.533; 95% CI: 0.357–0.796; p = 0.002), left ventricular end-diastolic dimension (OR: 0.940; 95% CI: 0.910–0.972; p &lt; 0.001), and sodium glucose cotransporter two inhibitors (OR: 5.634; 95% CI: 1.756–18.080; p = 0.004). A nomogram was constructed to present the results. The C-index of the model was 0.666 (95% CI, 0.613–0.719) and 0.656 after validation. The calibration curve demonstrated that the nomogram agreed with the actual observations.

Conclusions

We developed an simple and effective nomogram for predicting the occurrence of HFiEF in patients with HF, 1 year after successful CTO PCI without severe residual stenosis.

Myocardial Viability, Functional Status, and Collaterals of Patients With Chronically Occluded Coronary Arteries

Objective: Viability and functional assessments are recommended for indication and intervention for chronic coronary total occlusion (CTO). We aimed to evaluate myocardial viability and left ventricular (LV) functional status by using cardiovascular magnetic resonance (CMR) and to investigate the relationship between them and collaterals in patients with CTO.

Materials and Methods: We enrolled 194 patients with one CTO artery as detected by coronary angiography. Patients were scheduled for CMR within 1 week after coronary angiography.

Results: A total of 128 CTO territories (66%) showed scar based on late gadolinium enhancement (LGE) imaging. There were 1,112 segments in CTO territory, while only 198 segments (18%) subtended by the CTO artery showed transmural scar (i.e., >50% extent on LGE). Patients with viable myocardium had higher LV ejection fraction (LVEF) (56.7 ± 13.5% vs. 48.3 ± 15.4%, p < 0.001) than those with transmural scar. Angiographically, well-developed collaterals were found in 164 patients (85%). There was no significant correlation between collaterals and the presence of myocardial scar (p = 0.680) or between collaterals and LVEF (p = 0.191). Nevertheless, more segments with transmural scar were observed in patients with poorly-developed collaterals than in those with well-developed collaterals (25 vs. 17%, p = 0.010).

Conclusion: Myocardial infarction detected by CMR is widespread among patients with CTO, yet only a bit of transmural myocardial scar was observed within CTO territory. Limited number of segments with transmural scar is associated with preserved LV function. Well-developed collaterals are not related to the prevalence of myocardial scar or systolic functioning, but could be related to reduce number of non-viable segments subtended by the CTO artery.

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.

A Contemporary Definition of Periprocedural Myocardial Injury After Percutaneous Coronary Intervention of Chronic Total Occlusions

OBJECTIVES

The aim of this study was to assess the prognostic impact of post-procedural troponin T increase and mortality in patients undergoing percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) to define the threshold at which procedure-related myocardial injury drives mortality.

BACKGROUND

Coronary CTO recanalization represents the most technically challenging PCI. The complexity harbors a significant increased risk for complications with CTO PCI with compared with non-CTO PCI. However, there are evidenced biomarker cutoff levels that help identify those patients at risk for unfavorable clinical outcomes.

METHODS

A total of 3,712 consecutive patients undergoing PCI for at least 1 CTO lesion were enrolled, and comprehensive troponin T measurements were performed 6, 8, and 24 h after the procedure. All-cause mortality was defined as the primary study endpoint.

RESULTS

Using spline curve analysis, a more than 18-fold increase of troponin above the upper reference limit was significantly associated with mortality. In a Cox regression analysis, the crude hazard ratio was 2.32 (95% confidence interval: 1.83 to 2.93; p < 0.001) for a ≥18-fold increase compared with patients with post-procedural troponin increase <18-fold of the upper reference limit. Results remained virtually unchanged after bootstrap- or clinical confounder-based adjustment.

CONCLUSIONS

This large-scale outcome study demonstrates for the first time the prognostic value of post-procedural troponin T elevation after PCI in patients with CTOs. A threshold was defined for procedure-related myocardial injury in patients with CTOs to differentiate them from those without CTOs that may help guide post-procedural clinical care in this high-risk patient population.

Impact of treatment strategies on long-term outcome of CTO patients

BACKGROUND

The percutaneous coronary intervention (PCI) for chronic total occlusions (CTO) remains debated. Therefore the aim of this large-scale observational multi-center registry was to compare the long-term outcome of CTO patients undergoing different therapeutic approaches comparing successful CTO revascularization either by PCI or coronary artery bypass graft (CABG), failed CTO-PCI and optimal medical therapy (OMT) alone.

METHODS AND RESULTS

A total of 6630 CTO patients were enrolled from two high-volume centers to compare different treatment strategies. All procedures were performed by high-volume CTO operators in tertiary university hospital. Successful CTO-PCI was performed in 3906 patients, failed CTO-PCI in 1479 patients, 412 patients underwent CABG surgery and 833 patients were treated with OMT. During the 5-year follow-up period, 1019 (15%) patients died. Kaplan-Meier analysis unveiled a significantly improved long-term outcome for CTO patients undergoing revascularization either by PCI or by CABG compared to patients with failed CTO-PCI or OMT alone (log-rank P < 0.001). In the multivariate Cox-regression analysis successful CTO-PCI was associated with significantly improved long-term outcome compared to patients under OMT (adj. HR 0.39, 95%CI 0.33-0.45, P < 0.001) or CABG (adj. HR 0.68, 95%CI 0.53-0.86, P = 0.002) independent of clinical confounders encompassing age, BMI, diabetes, kidney function and left ventricular function.

CONCLUSIONS

This study showed an improved long-term outcome for CTO revascularization compared to optimal medical therapy, independent from revascularization mode, with the highest survival rate in patients undergoing successful CTO-PCI.

Scoring System for Identification of "Survival Advantage" after Successful Percutaneous Coronary Intervention in Patients with Chronic Total Occlusion

Background: Percutaneous coronary intervention (PCI) is widely used in patients with chronic total occlusion (CTO), but its benefit in improving long-term outcomes is controversial. We aimed to develop a prediction score for grading “survival advantage” conferred by successful results of CTO-PCI and a scoring system for prediction of the influence of CTO-PCI results on major adverse cardiac and cerebrovascular events (MACCEs). Methods: Follow-up data of 2625 patients who underwent CTO-PCI at 65 Japanese centers were analyzed. An integer scoring system was developed by including statistical effect modifiers on the association between successful CTO-PCI and one-year mortality. Results: Follow-up at 12 months was completed in 2034 patients. During follow-up, 76 deaths (3.7%) occurred. Patients with successful CTO-PCI had a better one-year survival than patients with failed CTO-PCI (log rank P = 0.016). Effect modifiers for the association between successful procedure and one-year mortality included diabetes (P interaction = 0.043), multivessel disease (P interaction = 0.175), Canadian Cardiovascular Society class ≥2 (P interaction = 0.088), and prior myocardial infarction (MI) (P interaction = 0.117). Each component was assigned a single point and summed to develop the scoring system. The patients were then categorized to specify the prediction of survival advantage by successful PCI: ≤2 (normal) and ≥3 (distinct). The differences in one-year mortality between patients with successful and failed treatment were −0.7% and 11.3% for normal and distinct score categories, respectively. In the scoring system for MACCE, score components were prior MI (P interaction = 0.19), left anterior descending artery (LAD)-CTO (P interaction = 0.079), and reattempt of CTO-PCI (P interaction = 0.18). The differences in one-year MACCEs between successful and failed patients for each score category (0, 1, and ≥2) were −1.7%, 7.5%, and 15.1%, respectively. Conclusions: The novel scoring system assessing the advantage of successful PCI can be easily applied in patients with CTO. It is a valid instrument for clinical decision-making while assessing the survival advantage of CTO-PCI and the influence of procedural results on MACCEs.

Left Main Coronary Artery Disease and Outcomes after Percutaneous Coronary Intervention for Chronic Total Occlusions

Background: Concomitant left main coronary artery (LMCA) disease in patients with chronic total occlusions (CTO) commonly results in referral for coronary artery bypass grafting, although the impact of LMCA in CTO patients remains largely unknown. Nevertheless, patient selection for percutaneous coronary intervention of CTOs (CTO-PCI) or alternative revascularization strategies should be based on precise evaluation of the coronary anatomy to anticipate those patients that most likely benefit from a procedure and not on strict adherence to perpetual clinical practice. Therefore, the aim of this study was to assess the impact of LMCA disease on long-term outcomes in patients undergoing percutaneous coronary intervention for CTO. Methods: We enrolled 3860 consecutive patients undergoing PCI for at least one CTO lesion and investigated the predictive value of concomitant LMCA disease. All-cause mortality was defined as the primary study endpoint. Results: We observed that LMCA disease is significantly associated with mortality. In the Cox regression analysis, we observed a crude hazard ratio (HR) 1.59 (95% confidence interval (CI) 1.23–2.04, p < 0.001) for patients with LMCA disease as compared to patients without. Results remained unchanged after bootstrap- or clinical confounder-based adjustment. Conclusion: LMCA disease is associated with excess mortality in CTO patients. Specifically, anatomical features such as CTO of the circumflex artery represent a high risk patient population.

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

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

Outcomes of Percutaneous Antegrade Intraluminal Coronary Intervention of Chronic Total Occlusion With Remote Surgical Backup

Percutaneous coronary intervention (PCI) of chronic total occlusion (CTO) is not favored in facilities without on-site surgical backup. We reviewed outcomes of patients who had CTO intervention with remote surgical backup in our institution. All patients who underwent attempted antegrade intraluminal CTO PCI from January 2013 to July 2017 were analyzed. Twenty cases (18 patients, 58.1 ± 7.0 years, 70% males) were identified. Procedure was successful in 85% (17 of 20). There were 2 nonflow limiting dissections and 1 wire perforation. Two patients had post-PCI myocardial infarction. There was no cardiac death, myocardial infarction, target vessel revascularization, or stroke at 30 days and at mean follow-up of 19.5 ± 13.7 months. There were 4 rehospitalizations for angina requiring repeat angiogram in 3 cases: 2 without intervention, and 1 referred for coronary artery bypass grafting. Careful attempt at antegrade intraluminal CTO intervention done at a center with remote surgical backup is feasible in selected patients.