Contemporary Issues in Chronic Total Occlusion Percutaneous Coronary Intervention

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

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

ObjectivesThe purpose of this study was to test whether the success rate of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) increased with pre-procedural coronary computed tomography angiography (CTA).BackgroundCoronary CTA provides valuable information before and during CTO-PCI. However, there are no randomized data that explore whether coronary CTA increases its success rate.MethodsIn this multicenter, randomized trial, a total of 400 patients with CTO were randomized to receive PCI with pre-procedural coronary CTA (coronary CTA–guided group; n = 200) or without coronary CTA (angiography-guided group; n = 200) between January 2014 and September 2019. The primary endpoint was the successful recanalization rate, a final TIMI (Thrombolysis In Myocardial Infarction) grade ≥2, and ≤30% residual stenosis on the final angiogram.ResultsA total of 10 operators performed PCI. Successful recanalization was achieved in 187 patients (93.5%) in the coronary CTA–guided group and in 168 patients (84.0%) in the angiography-guided group (absolute difference, 9.5% [95% confidence interval: 3.4% to 15.6%]; p = 0.003). When comparing the success rates according to the Multicenter CTO Registry of Japan score (J-CTO), the coronary CTA guidance was favored over the angiography-guidance in the subset of J-CTO ≥2 versus in the subset of J-CTO <2 (p interaction = 0.035). Coronary perforations occurred in 2 (1%) and 8 patients (4%) in the coronary CTA- and angiography-guided groups, respectively (p = 0.055). Periprocedural myocardial infarction was not observed in the coronary CTA–guided group, whereas it occurred in 4 patients (2%) in the angiography-guided group (p = 0.123). Total procedure and fluoroscopic times were not different. There were no differences between the groups in the occurrences of cardiac death, target vessel–related myocardial infarction, or target-vessel revascularization at 1 year.ConclusionsPre-procedural coronary CTA-guidance for CTO resulted in higher success rates with numerically fewer immediate periprocedural complications such as coronary perforations or periprocedural myocardial infarction than angiography guidance. Higher success rates were more prominently observed in patients with CTO who had a high J-CTO score than those who did not. (Role of CT Scan for the Successful Recanalization of Chronic Total Occlusion; a Randomized Comparison Between 3D CT-guided PCI vs. Conventional Treatment [CT-CTO Trial]; NCT02037698)     

Stent-Related Adverse Events >1 Year After Percutaneous Coronary Intervention

BackgroundThe majority of stent-related major adverse cardiovascular events (MACE) after percutaneous coronary intervention (PCI) are believed to occur within the first year. Very-late (>1-year) stent-related MACE have not been well described.ObjectivesThe purpose of this study was to assess the frequency and predictors of very-late stent-related events or MACE by stent type.MethodsIndividual patient data from 19 prospective, randomized metallic stent trials maintained at a leading academic research organization were pooled. Very-late MACE (a composite of cardiac death, myocardial infarction [MI], or ischemia-driven target lesion revascularization [ID-TLR]), and target lesion failure (cardiac death, target-vessel MI, or ID-TLR) were assessed within year 1 and between 1 and 5 years after PCI with bare-metal stents (BMS), first-generation drug-eluting stents (DES1) and second-generation drug-eluting stents (DES2). A network meta-analysis was performed to evaluate direct and indirect comparisons.ResultsAmong 25,032 total patients, 3,718, 7,934, and 13,380 were treated with BMS, DES1, and DES2, respectively. MACE rates within 1 year after PCI were progressively lower after treatment with BMS versus DES1 versus DES2 (17.9% vs. 8.2% vs. 5.1%, respectively, p < 0.0001). Between years 1 and 5, very-late MACE occurred in 9.4% of patients (including 2.9% cardiac death, 3.1% MI, and 5.1% ID-TLR). Very-late MACE occurred in 9.7%, 11.0%, and 8.3% of patients treated with BMS, DES1, and DES2, respectively (p < 0.0001), linearly increasing between 1 and 5 years. Similar findings were observed for target lesion failure in 19,578 patients from 12 trials. Findings were confirmed in the network meta-analysis.ConclusionsIn this large-scale, individual patient data pooled study, very-late stent-related events occurred between 1 and 5 years after PCI at a rate of ∼2%/year with all stent types, with no plateau evident. New approaches are required to improve long-term outcomes after PCI.     

Subintimal Versus Intraplaque Recanalization of Coronary Chronic Total Occlusions: Mid-Term Angiographic and OCT Findings From the ISAR-OCT-CTO Registry

ObjectivesThe aim of this study was to compare angiographic and optical coherence tomography findings following subintimal as opposed to intraplaque recanalization of chronic total occlusions (CTOs).BackgroundThere is ongoing controversy regarding outcomes of intraplaque versus subintimal CTO recanalization.MethodsConsecutive patients undergoing angiography and intravascular optical coherence tomography following CTO recanalization were included in the ISAR-OCT-CTO (Intracoronary Stenting and Angiographic Results - Optical Coherence Tomography for Chronic Total Occlusions) registry. The study endpoints were percent diameter stenosis and late lumen loss as well as rate of uncovered and malapposed struts. Independent correlates of uncovered and malapposed struts were assessed by multivariate analysis.ResultsThe study included 75 patients. Intraplaque and dissection and re-entry techniques (DART) were used in 46 and 29 patients, respectively. There were no differences in terms of in-segment percent diameter stenosis (median 36.9 [interquartile range (IQR): 26.4 to 43.1] vs. 31.2 [IQR: 23.2 to 49.5]; p = 0.656), in-stent late lumen loss (0.215 mm [IQR: 0.063 to 0.495 mm] vs. 0.230 mm [IQR: 0.060 to 0.645 mm]; p = 0.837), or in-segment late lumen loss (0.030 mm [IQR: −0.278 to 0.510 mm] vs. 0.130 mm [IQR: −0.120 to 0.500 mm]; p = 0.395) at follow-up between the 2 techniques. Optical coherence tomography analysis showed comparable strut coverage (79.9% vs. 71.3%; p = 0.255) but significantly higher strut malapposition (6.6% vs. 13.6%; p < 0.001) following DART. Use of DART independently correlated with presence of strut malapposition (odds ratio: 3.41; 95% confidence interval: 1.24 to 9.36; p = 0.017) but not of strut coverage (odds ratio: 0.65; 95% confidence interval: 0.28 to 1.49; p = 0.314).ConclusionsIntraplaque and subintimal recanalization techniques are associated with comparable mid-term angiographic results. Although the rate of uncovered struts is high following CTO recanalization, the recanalization technique does not independently correlate with presence of uncovered struts. There is a high rate of strut malapposition following CTO recanalization, particularly if achieved by means of DART.     

Multivessel Versus Culprit-Vessel Percutaneous Coronary Intervention in Cardiogenic Shock

ObjectivesThis study sought to compare outcomes of patients enrolled in the NCSI (National Cardiogenic Shock Initiative) trial who were treated using a revascularization strategy of percutaneous coronary intervention (PCI) of multivessel PCI (MV-PCI) versus culprit-vessel PCI (CV-PCI).BackgroundIn patients with multivessel disease who present with acute myocardial infarction and cardiogenic shock (AMICS), intervening on the nonculprit vessel is controversial. There are conflicting published reports and lack of evidence, particularly in patients treated with early mechanical circulatory support (MCS).MethodsFrom July 2016 to December 2019, patients who presented with AMICS to 57 participating hospitals were included in this analysis. All patients were treated using a standard shock protocol emphasizing early MCS, revascularization, and invasive hemodynamic monitoring. Patients with multivessel coronary artery disease (MVCAD) were analyzed according to whether CV-PCI or MV-PCI was undertaken during the index procedure.ResultsOf 198 patients with MVCAD, 126 underwent MV-PCI (64%) and 72 underwent CV-PCI (36%). Demographics between the cohorts were similar with respect to age, sex, history of diabetes, prior PCI or coronary artery bypass grafting, and prior history of myocardial infarction. Patients who underwent MV-PCI had a trend toward more severe impairment of cardiac output and worse lactate clearance on presentation, and cardiac performance was significantly worse at 12 h. However, 24 h from PCI, the hemometabolic derangements were similar. Survival and rates of acute kidney injury were not significantly different between groups (69.8% MV-PCI vs. 65.3% CV-PCI; p = 0.51; and 29.9% vs. 34.2%; p = 0.64, respectively).ConclusionsIn patients with MVCAD presenting with AMICS treated with early MCS, revascularization of nonculprit lesions was associated with similar hospital survival and acute kidney injury when compared with culprit-only PCI. Selective nonculprit PCI can be safety performed in AMICS in patients supported with mechanical circulatory support.     

Long-Term Outcomes in Women and Men Following Percutaneous Coronary Intervention

BackgroundStudies examining sex-related outcomes following percutaneous coronary intervention (PCI) have reported conflicting results.ObjectivesThe purpose of this study was to examine the sex-related risk of 5-year cardiovascular outcomes after PCI.MethodsThe authors pooled patient-level data from 21 randomized PCI trials and assessed the association between sex and major adverse cardiac events (MACE) (cardiac death, myocardial infarction [MI], or ischemia-driven target lesion revascularization [ID-TLR]) as well as its individual components at 5 years.ResultsAmong 32,877 patients, 9,141 (27.8%) were women. Women were older and had higher body mass index, more frequent hypertension and diabetes, and less frequent history of surgical or percutaneous revascularization compared with men. By angiographic core laboratory analysis, lesions in women had smaller reference vessel diameter and shorter lesion length. At 5 years, women had a higher unadjusted rate of MACE (18.9% vs. 17.7%; p = 0.003), all-cause death (10.4% vs. 8.7%; p = 0.0008), cardiac death (4.9% vs. 4.0%; p = 0.003) and ID-TLR (10.9% vs. 10.2%; p = 0.02) compared with men. By multivariable analysis, female sex was an independent predictor of MACE (hazard ratio [HR:]: 1.14; 95% confidence interval [CI:]: 1.01 to 1.30; p = 0.04) and ID-TLR (HR: 1.23; 95% CI: 1.05 to 1.44; p = 0.009) but not all-cause death (HR: 0.91; 95% CI: 0.75 to 1.09; p = 0.30) or cardiac death (HR: 0.97; 95% CI: 0.73 to 1.29; p = 0.85).ConclusionsIn the present large-scale, individual patient data pooled analysis of contemporary PCI trials, women had a higher risk of MACE and ID-TLR compared with men at 5 years following PCI.     

In-Stent CTO Percutaneous Coronary Intervention: Individual Patient Data Pooled Analysis of 4 Multicenter Registries

ObjectivesThe authors sought to examine the outcomes of percutaneous coronary intervention (PCI) for in-stent restenosis (ISR) chronic total occlusions (CTOs).BackgroundThe outcomes of PCI for ISR CTOs have received limited study.MethodsThe authors examined the clinical and angiographic characteristics and procedural outcomes of 11,961 CTO PCIs performed in 11,728 patients at 107 centers in Europe, North America, Latin America, and Asia between 2012 and 2020, pooling patient-level data from 4 multicenter registries. In-hospital major adverse cardiovascular events (MACE) included death, myocardial infarction, stroke, and tamponade. Long-term MACE were defined as the composite of all-cause death, myocardial infarction, and target vessel revascularization.ResultsISR represented 15% of the CTOs (n = 1,755). Patients with ISR CTOs had higher prevalence of diabetes (44% vs. 38%; p < 0.0001) and prior coronary artery bypass graft surgery (27% vs. 24%; p = 0.03). Mean J-CTO (Multicenter CTO Registry in Japan) score was 2.32 ± 1.27 in the ISR group and 2.22 ± 1.27 in the de novo group (p = 0.01). Technical (85% vs. 85%; p = 0.75) and procedural (84% vs. 84%; p = 0.82) success was similar for ISR and de novo CTOs, as was the incidence of in-hospital MACE (1.7% vs. 2.2%; p = 0.25). Antegrade wiring was the most common successful strategy, in 70% of ISR and 60% of de novo CTOs, followed by retrograde crossing (16% vs. 23%) and antegrade dissection and re-entry (15% vs. 16%; p < 0.0001). At 12 months, patients with ISR CTOs had a higher incidence of MACE (hazard ratio: 1.31; 95% confidence interval: 1.01 to 1.70; p = 0.04).ConclusionsISR CTOs represent 15% of all CTO PCIs and can be recanalized with similar success and in-hospital MACE as de novo CTOs.     

Retrograde Chronic Total Occlusion Percutaneous Coronary Intervention via Saphenous Vein Graft

ObjectivesThe aim of this study was to examine the use of saphenous vein grafts (SVGs) for retrograde crossing during chronic total occlusion (CTO) percutaneous coronary intervention (PCI).BackgroundThe use of SVGs for retrograde crossing during CTO PCI has received limited study.MethodsA total of 1,615 retrograde CTO PCIs performed between 2012 and 2019 at 25 centers were examined. Clinical, angiographic, and technical characteristics and procedural outcomes were compared among retrograde cases via SVGs (SVG group) versus other collateral vessels (non-SVG group).ResultsRetrograde CTO PCI via SVGs was performed in 189 cases (12%). Patients in the SVG group were older (mean age 70 ± 9 years vs. 64 ± 10 years; p < 0.01) and had higher rates of prior myocardial infarction (62% vs. 51%; p < 0.01) and prior PCI (81% vs. 70%; p < 0.01). They were more likely to have moderate or severe calcification (81% vs. 65%; p < 0.01) and moderate or severe tortuosity (53% vs. 44%; p = 0.02) and had similar J-CTO (Multicenter CTO Registry in Japan) scores (3.2 ± 1.0 vs. 3.1 ± 1.1; p = 0.13) but higher PROGRESS-CTO (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention) scores (4.7 ± 1.7 vs. 3.1 ± 1.1; p < 0.01). Technical (85% vs. 78%; p = 0.04) and procedural (81% vs. 74%; p = 0.04) success rates were higher in the SVG group, with no difference in in-hospital major adverse events (6.4% vs. 4.4%; p = 0.22). Contrast volume was lower in the SVG group (225 ml [173 to 325 ml] vs. 292 ml [202 to 400 ml]; p < 0.01).ConclusionsUse of SVGs for retrograde crossing is associated with higher rates of technical and procedural success and similar rates of in-hospital major adverse cardiac events compared with retrograde CTO PCI via other collateral vessels.     

Uninterrupted Oral Anticoagulant Therapy in Patients Undergoing Unplanned Percutaneous Coronary Intervention

ObjectivesThis study sought to compare interrupted and uninterrupted oral anticoagulant therapy (I-OAC vs. U-OAC) in patients on OAC undergoing percutaneous coronary intervention.BackgroundThere is a paucity of data regarding the optimal peri-procedural management of OAC-treated patients.MethodsIn the SWEDEHEART registry, all patients on OAC who were admitted acutely and underwent percutaneous coronary intervention or coronary angiography with a diagnostic procedure, from 2005 to 2017, were included. Outcomes were major adverse cardiac and cerebrovascular events (MACCE; death, myocardial infarction, or stroke) and bleeds at 120 days. Propensity score was used to adjust for the nonrandomized treatment selection.ResultsThe study included 6,485 patients: 3,322 in the I-OAC group and 3,163 in the U-OAC group. The cumulative incidence of MACCE was 8.2% (269 events) versus 8.2% (254 events) in the I-OAC and the U-OAC groups, respectively. The adjusted risk for MACCE did not differ between the groups (I-OAC vs. U-OAC hazard ratio: 0.89; 95% confidence interval: 0.71 to 1.12). Similarly, no difference was found in the risk for MACCE or bleeds (12.6% vs. 12.9%, adjusted hazard ratio: 0.87; 95% confidence interval: 0.70 to 1.07). The risk for major or minor in-hospital bleeds did not differ between the groups. However, U-OAC was associated with a significantly shorter duration of hospitalization: 4 (3 to 7) days versus 5 (3 to 8) days; p < 0.01.ConclusionsI-OAC and U-OAC were associated with equivalent risk for MACCE and bleeding complications. An U-OAC strategy was associated with shorter length of hospitalization. These data support U-OAC as the preferable strategy in patients on OAC undergoing coronary intervention.     

Blinded Physiological Assessment of Residual Ischemia After Successful Angiographic Percutaneous Coronary Intervention: The DEFINE PCI Study

ObjectivesThis study sought to evaluate the incidence and causes of an abnormal instantaneous wave-free ratio (iFR) after angiographically successful percutaneous coronary intervention (PCI).BackgroundImpaired coronary physiology as assessed by fractional flow reserve is present in some patients after PCI and is prognostically relevant.MethodsDEFINE PCI (Physiologic Assessment of Coronary Stenosis Following PCI) was a multicenter, prospective, observational study in which a blinded iFR pull back was performed after angiographically successful PCI in 562 vessels in 500 patients. Inclusion criteria were angina with either multivessel or multilesion coronary artery disease with an abnormal baseline iFR. The primary endpoint of the study was the rate of residual ischemia after operator-assessed angiographically successful PCI, defined as an iFR <0.90. The causes of impaired iFR were categorized as stent related, untreated proximal or distal focal stenosis, or diffuse atherosclerosis.ResultsAn average of 1.1 vessels per patient had abnormal baseline iFRs, with a mean value of 0.69 ± 0.22, which improved to 0.93 ± 0.07 post-PCI. Residual ischemia after angiographically successful PCI was present in 112 patients (24.0%), with a mean iFR in that population of 0.84 ± 0.06 (range 0.60 to 0.89). Among patients with impaired post-PCI iFRs, 81.6% had untreated focal stenoses that were angiographically inapparent, and 18.4% had diffuse disease. Among the focal lesions, 38.4% were located within the stent segment, while 31.5% were proximal and 30.1% were distal to the stent. Post-PCI vessel angiographic diameter stenosis was not a predictor of impaired post-procedural iFR.ConclusionsBlinded post-PCI physiological assessment detected residual ischemia in nearly 1 in 4 patients after coronary stenting despite an operator-determined angiographically successful result. Most cases of residual ischemia were due to inapparent focal lesions potentially amenable to treatment with additional PCI. (Physiologic Assessment of Coronary Stenosis Following PCI [DEFINE PCI]; NCT03084367)     

Left Ventricular Filling Pressure in Chronic Thromboembolic Pulmonary Hypertension

BackgroundChronic thromboembolic pulmonary hypertension (CTEPH) is characterized by obstruction of major pulmonary arteries with organized thrombi. Clinical risk factors for pulmonary hypertension due to left heart disease including metabolic syndrome, left-sided valvular heart disease, and ischemic heart disease are common in CTEPH patients.ObjectivesThe authors sought to investigate prevalence and prognostic implications of elevated left ventricular filling pressures (LVFP) in CTEPH.MethodsA total of 593 consecutive CTEPH patients undergoing a first diagnostic right and left heart catheterization were included in this study. Mean pulmonary arterial wedge pressure (mPAWP) and left ventricular end-diastolic pressure (LVEDP) were utilized for assessment of LVFP. Two cutoffs were applied to identify patients with elevated LVFP: 1) for the primary analysis mPAWP and/or LVEDP >15 mm Hg, as recommended by the current pulmonary hypertension guidelines; and 2) for the secondary analysis mPAWP and/or LVEDP >11 mm Hg, representing the upper limit of normal. Clinical and echocardiographic features, and long-term mortality were assessed.ResultsLVFP was >15 mm Hg in 63 (10.6%) and >11 mm Hg in 222 patients (37.4%). Univariable logistic regression analysis identified age, systemic hypertension, diabetes, atrial fibrillation, calcific aortic valve stenosis, mitral regurgitation, and left atrial volume as significant predictors of elevated LVFP. Atrial fibrillation, calcific aortic valve stenosis, mitral regurgitation, and left atrial volume remained independent determinants of LVFP in adjusted analysis. At follow-up, higher LVFPs were measured in patients who had meanwhile undergone pulmonary endarterectomy (P = 0.002). LVFP >15 mm Hg (P = 0.021) and >11 mm Hg (P = 0.006) were both associated with worse long-term survival.ConclusionsElevated LVFP is common, appears to be due to comorbid left heart disease, and predicts prognosis in CTEPH.     

Antithrombotic Management of Elderly Patients With Coronary Artery Disease

Antithrombotic therapy represents the mainstay of treatment in patients with coronary artery disease (CAD), including elderly patients who are at increased risk for ischemic recurrences. However, the elderly population is also more vulnerable to bleeding complications. Numerous mechanisms, including abnormalities in the vasculature, thrombogenicity, comorbidities, and altered drug response, contribute to both increased thrombotic and bleeding risk. Age-related organ changes and drug-drug interactions secondary to polypharmacy lead to distinct pharmacokinetic and pharmacodynamic profiles of antithrombotic drugs. Overall these factors contribute to the risk-benefit profiles of antithrombotic therapies in elderly subjects and underscore the need for treatment regimens that can reduce bleeding while preserving efficacy. Given that the prevalence of CAD, as well as concomitant diseases with thromboembolic potential, such as atrial fibrillation, increases with age and that the elderly population is in continuous growth, understanding the safety and efficacy of different antithrombotic regimens is pivotal for patient-centered care. In the present overview the authors appraise the available data on the use of antithrombotic therapy in older patients with CAD to assist with the management of this high-risk population and define knowledge gaps that can set the basis for future research.     

Short Duration of DAPT Versus De-Escalation After Percutaneous Coronary Intervention for Acute Coronary Syndromes

ObjectivesThe aim of this study was to compare short dual antiplatelet therapy (DAPT) and de-escalation in a network meta-analysis using standard DAPT as common comparator.BackgroundIn patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI), shortening DAPT and de-escalating to a lower potency regimen mitigate bleeding risk. These strategies have never been randomly compared.MethodsRandomized trials of DAPT modulation strategies in patients with ACS undergoing PCI were identified. All-cause death was the primary outcome. Secondary outcomes included net adverse cardiovascular events (NACE), major adverse cardiovascular events, and their components. Frequentist and Bayesian network meta-analyses were conducted. Treatments were ranked on the basis of posterior probability. Sensitivity analyses were performed to explore sources of heterogeneity.ResultsTwenty-nine studies encompassing 50,602 patients were included. The transitivity assumption was fulfilled. In the frequentist indirect comparison, the risk ratio (RR) for all-cause death was 0.98 (95% CI: 0.68-1.43). De-escalation reduced the risk for NACE (RR: 0.87; 95% CI: 0.70-0.94) and increased major bleeding (RR: 1.54; 95% CI: 1.07-2.21). These results were consistent in the Bayesian meta-analysis. De-escalation displayed a >95% probability to rank first for NACE, myocardial infarction, stroke, stent thrombosis, and minor bleeding, while short DAPT ranked first for major bleeding. These findings were consistent in node-split and multiple sensitivity analyses.ConclusionsIn patients with ACS undergoing PCI, there was no difference in all-cause death between short DAPT and de-escalation. De-escalation reduced the risk for NACE, while short DAPT decreased major bleeding. These data characterize 2 contemporary strategies to personalize DAPT on the basis of treatment objectives and risk profile.     

Institutional Variability in Patient Radiation Doses ≥5 Gy During Percutaneous Coronary Intervention

ObjectivesThe aim of this study was to evaluate institutional variability in high radiation doses during percutaneous coronary intervention (PCI).BackgroundIt is unknown whether radiation safety practices are optimally applied across institutions performing PCI.MethodsUsing data from a large statewide registry, PCI discharges between July 1, 2016, and March 31, 2018, with a procedural air kerma (AK) recorded were analyzed. PCI procedures were grouped by the performing hospital, and institutional frequency of procedural AK ≥5 Gy was calculated. Fitted hierarchical Bayesian modeling was performed to identify variables independently associated with an AK ≥5 Gy. The performing hospital was included as a random effect in the hierarchical model.ResultsAmong 36,201 PCI procedures at 28 hospitals, procedural AK was ≥5 Gy in 1,477 cases (4.1%), ≥10 Gy in 185 (0.5%), and ≥15 Gy in 105 (0.3%). The institutional frequency of procedural AK ≥5 Gy ranged from 0.0% to 10.9%. Bayesian modeling identified body mass index, dyslipidemia, diabetes, prior coronary bypass surgery, use of mechanical circulatory support, and the performing hospital as independent predictors of an AK ≥5 Gy. The median odds ratio for the performing hospital, representing an estimate of the contribution of interhospital variability in determining the odds of having a procedural AK ≥5 Gy, was 3.08 (95% confidence interval: 3.01 to 3.16).ConclusionsWide variability exists in the institutional frequency of procedural AK ≥5 Gy during PCI. After accounting for patient characteristics and procedural variables, the performing hospital appears to be a major factor in determining patient radiation dose in contemporary PCI.     

Critical Appraisal of Contemporary Clinical Endpoint Definitions in Coronary Intervention Trials: A Guidance Document

The Academic Research Consortium (ARC) and the Standardized Data Collection for Cardiovascular Trials Initiative have recently published updated clinical and angiographic endpoint definitions for percutaneous coronary intervention trials. The aim of this document is to provide practical guidance to facilitate and harmonize the implementation of those definitions in randomized trials or registries, as well as to foster consistency among independent adjudication committees. The authors compared the ARC-2 and Standardized Data Collection for Cardiovascular Trials Initiative definitions to identify areas of consistency, complex scenarios, and definitions in need of further standardization. Furthermore, the authors compared the fourth universal definition of myocardial infarction with the ARC-2 definition of myocardial infarction. The Society for Cardiovascular Angiography and Interventions definition of periprocedural myocardial infarction was also compared with the ARC-2 definition and the fourth universal definition of myocardial infarction. An in-depth assessment was done for each individual clinical endpoint to guide clinical investigators on reporting and classifying clinical adverse events. Finally, the authors propose standard streamlined data capture templates for reporting and adjudicating death, myocardial infarction, stroke, revascularization, stent or scaffold thrombosis, and bleeding.     

Long-Term Outcomes of Coronary Stenting With and Without Use of Intravascular Ultrasound

ObjectivesThis study sought to explore if intravascular ultrasound (IVUS) use in real-world patients is associated with improved long-term outcomes of percutaneous coronary intervention (PCI).BackgroundThe benefit of IVUS use with PCI in real world is uncertain.MethodsWe identified Medicare patients who underwent PCI from 2009 to 2017 and evaluated the association of IVUS use with long-term risk of mortality, myocardial infarction (MI), and repeat revascularization. We used propensity score matching and inverse probability weighting to adjust for baseline characteristics. To account for hospital effects, patients undergoing IVUS-guided PCI were matched to non-IVUS patients in the same hospital and year. Sensitivity analyses comparing outcomes with and without IVUS in stable coronary artery disease and acute coronary syndrome, PCI with bare-metal stents and drug-eluting stents, complex and noncomplex PCI, and facilities with 1% to 5%, 5% to 10%, and >10% IVUS use were performed.ResultsOverall, IVUS was used in 5.6% of all PCI patients (105,787 out of 1,877,177 patients). Patients with IVUS-guided PCI had a higher prevalence of most comorbidities. In the propensity matched analysis, IVUS-guided PCI was associated with lower 1-year mortality (11.5% vs. 12.3%), MI (4.9% vs. 5.2%), and repeat revascularization (6.1% vs. 6.7%) (p < 0.001 for all). In inverse probability weighting analysis with a median follow-up of 3.7 years (interquartile range: 1.7 to 6.4 years), IVUS-guided PCI was associated with a lower risk of mortality (adjusted hazard ratio [aHR]: 0.903; 95% confidence interval [CI]: 0.885 to 0.922), MI (aHR: 0.899; 95% CI: 0.893 to 0.904), and repeat revascularization (aHR: 0.893; 95% CI: 0.887 to 0.898) (p < 0.001 for all). These findings were consistent in all subgroups in sensitivity analyses.ConclusionsIn this contemporary U.S. Medicare cohort, the use of IVUS guidance in PCI remains low. Use of IVUS is associated with lower long-term mortality, MI, and repeat revascularization.     

Retrograde Chronic Total Occlusion Percutaneous Coronary Interventions: Predictors of Procedural Success From the ERCTO Registry

ObjectivesThe aim of this study was to identify independent predictors of procedural success after retrograde chronic total occlusion (CTO) percutaneous coronary intervention (PCI).BackgroundRetrograde CTO PCI is an established technique, but predictors of success remain poorly understood.MethodsA multivariable logistic regression model was used to analyze potentially important demographic, clinical, anatomical, and technical aspects of retrograde CTO PCI cases uploaded to the multicenter European CTO (ERCTO) Club Registry.ResultsIn calendar years 2018 and 2019, 2,364 retrograde CTO PCI cases constituted the primary analysis cohort. A primary retrograde strategy was used in 1,953 cases (82.6%), and an initial antegrade approach was converted to retrograde in 411 cases (17.4%). Procedural success was achieved in 1,820 cases (77.0%) and was more likely to occur after a primary retrograde attempt versus conversion from an initial antegrade approach (80.9% vs 58.4%; P < 0.0001). After multivariable analysis, an absence of lesion calcification (OR: 1.86; 95% CI: 1.37-2.51; P < 0.0001), a higher degree of distal vessel opacification (OR: 2.47; 95% CI: 1.72-3.55; P < 0.0001), little or no proximal target vessel tortuosity (OR: 1.84; 95% CI: 1.28-2.64; P = 0.001), Werner collateral connection CC1 (OR: 4.87; 95% CI: 2.90-8.19; P < 0.0001) or CC2 (OR: 5.33; 95% CI: 3.02-9.42; P < 0.0001), and the top tertile of operator volume (>120 cases over 2 years) (OR: 1.88; 95% CI: 1.26-2.79; P = 0.002) were associated with the greatest chance of achieving angiographic success.ConclusionsLess calcification with good distal vessel opacification, little or absent proximal vessel tortuosity, and visible collateral connections, along with high-volume operator status, were all independently predictive of angiographically successful retrograde CTO PCI.     

Coronary CT Angiography in Patients With Non-ST-Segment Elevation Acute Coronary Syndrome

BackgroundIn patients with non–ST-segment elevation acute coronary syndrome (NSTEACS), coronary pathology may range from structurally normal vessels to severe coronary artery disease.ObjectivesThe purpose of this study was to test if coronary computed tomography angiography (CTA) may be used to exclude coronary artery stenosis ≥50% in patients with NSTEACS.MethodsThe VERDICT (Very Early Versus Deferred Invasive Evaluation Using Computerized Tomography in Patients With Acute Coronary Syndromes) trial (NCT02061891) evaluated the outcome of patients with confirmed NSTEACS randomized 1:1 to very early (within 12 h) or standard (48 to 72 h) invasive coronary angiography (ICA). As an observational component of the trial, a clinically blinded coronary CTA was conducted prior to ICA in both groups. The primary endpoint was the ability of coronary CTA to rule out coronary artery stenosis (≥50% stenosis) in the entire population, expressed as the negative predictive value (NPV), using ICA as the reference standard.ResultsCoronary CTA was conducted in 1,023 patients—very early, 2.5 h (interquartile range [IQR]: 1.8 to 4.2 h), n = 583; and standard, 59.9 h (IQR: 38.9 to 86.7 h); n = 440 after the diagnosis of NSTEACS was made. A coronary stenosis ≥50% was found by coronary CTA in 68.9% and by ICA in 67.4% of the patients. Per-patient NPV of coronary CTA was 90.9% (95% confidence interval [CI]: 86.8% to 94.1%) and the positive predictive value, sensitivity, and specificity were 87.9% (95% CI: 85.3% to 90.1%), 96.5% (95% CI: 94.9% to 97.8%) and 72.4% (95% CI: 67.2% to 77.1%), respectively. NPV was not influenced by patient characteristics or clinical risk profile and was similar in the very early and the standard strategy group.ConclusionsCoronary CTA has a high diagnostic accuracy to rule out clinically significant coronary artery disease in patients with NSTEACS.     

Updated Expert Consensus Statement on Platelet Function and Genetic Testing for Guiding P2Y12 Receptor Inhibitor Treatment in Percutaneous Coronary Intervention

Dual-antiplatelet therapy (DAPT) with aspirin and a P2Y₁₂ receptor inhibitor is the standard treatment for patients undergoing percutaneous coronary intervention. The availability of different P2Y₁₂ receptor inhibitors (clopidogrel, prasugrel, ticagrelor) with varying levels of potency has enabled physicians to contemplate individualized treatment regimens, which may include escalation or de-escalation of P2Y₁₂-inhibiting therapy. Indeed, individualized and alternative DAPT strategies may be chosen according to the clinical setting (stable coronary artery disease vs. acute coronary syndrome), the stage of the disease (early- vs. long-term treatment), and patient risk for ischemic and bleeding complications. A tailored DAPT approach may be potentially guided by platelet function testing (PFT) or genetic testing. Although the routine use of PFT or genetic testing in percutaneous coronary intervention–treated patients is not recommended, recent data have led to an update in guideline recommendations that allow considering selective use of PFT for DAPT de-escalation. However, guidelines do not expand on when to implement the selective use of such assays into decision making for personalized treatment approaches. Therefore, an international expert consensus group of key leaders from North America, Asia, and Europe with expertise in the field of antiplatelet treatment was convened. This document updates 2 prior consensus papers on this topic and summarizes the contemporary updated expert consensus recommendations for the selective use of PFT or genotyping in patients undergoing percutaneous coronary intervention.     

A Detailed Analysis of Perforations During Chronic Total Occlusion Angioplasty

ObjectivesThis study sought to describe the angiographic characteristics, strategy associated with perforation, and the management of perforation during chronic total occlusion percutaneous coronary intervention (CTO PCI).BackgroundThe incidence of perforation is higher during CTO PCI compared with non-CTO PCI and is reportedly highest among retrograde procedures.MethodsAmong 1,000 consecutive patients who underwent CTO PCI in a 12-center registry, 89 (8.9%) had core lab–adjudicated angiographic perforations. Clinical perforation was defined as any perforation requiring treatment. Major adverse cardiac events (MAEs) were defined as in-hospital death, cardiac tamponade, and pericardial effusion.ResultsAmong the 89 perforations, 43 (48.3%) were clinically significant, and 46 (51.7%) were simply observed. MAE occurred in 25 (28.0%), and in-hospital death occurred in 9 (10.1%). Compared with nonclinical perforations, clinical perforations were larger in size, more often at a collateral location, had a high-risk shape, and less likely to cause staining or fast filling. Compared with perforations not associated with MAE, perforations associated with MAE were larger in size, more proximal or at collateral location, and had a high-risk shape. When the core lab attributed the perforation to the approach used when the perforation occurred, 61% of retrograde perforations by other classifications were actually antegrade.ConclusionsLarger size, proximal or collateral location, and high-risk shapes of a coronary perforation were associated with MAE. Six of 10 perforations occurred with antegrade approaches among patients who had both strategies attempted. These finding will help emerging CTO operators understand high-risk features of the perforation that require treatment and inform future comparisons of retrograde and antegrade complications.