Artificial intelligence-based quantitative coronary angiography of major vessels using deep-learning

BACKGROUND

Quantitative coronary angiography (QCA) offers objective and reproducible measures of coronary lesions. However, significant inter- and intra-observer variability and time-consuming processes hinder the practical application of on-site QCA in the current clinical setting. This study proposes a novel method for artificial intelligence-based QCA (AI-QCA) analysis of the major vessels and evaluates its performance.

METHODS

AI-QCA was developed using three deep-learning models trained on 7658 angiographic images from 3129 patients for the precise delineation of lumen boundaries. An automated quantification method, employing refined matching for accurate diameter calculation and iterative updates of diameter trend lines, was embedded in the AI-QCA. A separate dataset of 676 coronary angiography images from 370 patients was retrospectively analyzed to compare AI-QCA with manual QCA performed by expert analysts. A match was considered between manual and AI-QCA lesions when the minimum lumen diameter (MLD) location identified manually coincided with the location identified by AI-QCA. Matched lesions were evaluated in terms of diameter stenosis (DS), MLD, reference lumen diameter (RLD), and lesion length (LL).

RESULTS

AI-QCA exhibited a sensitivity of 89% in lesion detection and strong correlations with manual QCA for DS, MLD, RLD, and LL. Among 995 matched lesions, most cases (892 cases, 80%) exhibited DS differences ≤10%. Multiple lesions of the major vessels were accurately identified and quantitatively analyzed without manual corrections.

CONCLUSION

AI-QCA demonstrates promise as an automated tool for analysis in coronary angiography, offering potential advantages for the quantitative assessment of coronary lesions and clinical decision-making.

Quantitative Coronary Angiography vs Intravascular Ultrasonography to Guide Drug-Eluting Stent Implantation: A Randomized Clinical Trial

Importance

Although intravascular ultrasonography (IVUS) guidance promotes favorable outcomes after percutaneous coronary intervention (PCI), many catheterization laboratories worldwide lack access.

Objective

To investigate whether systematic implementation of quantitative coronary angiography (QCA) to assist angiography-guided PCI could be an alternative strategy to IVUS guidance during stent implantation.

Design, Setting, and Participants

This randomized, open-label, noninferiority clinical trial enrolled adults (aged ≥18 years) with chronic or acute coronary syndrome and angiographically confirmed native coronary artery stenosis requiring PCI. Patients were enrolled in 6 cardiac centers in Korea from February 23, 2017, to August 23, 2021, and follow-up occurred through August 25, 2022. All principal analyses were performed according to the intention-to-treat principle.

Interventions

After successful guidewire crossing of the first target lesion, patients were randomized in a 1:1 ratio to receive either QCA- or IVUS-guided PCI.

Main Outcomes and Measures

The primary outcome was target lesion failure at 12 months, defined as a composite of cardiac death, target vessel myocardial infarction, or ischemia-driven target lesion revascularization. The trial was designed assuming an event rate of 8%, with the upper limit of the 1-sided 97.5% CI of the absolute difference in 12-month target lesion failure (QCA-guided PCI minus IVUS-guided PCI) to be less than 3.5 percentage points for noninferiority.

Results

The trial included 1528 patients who underwent PCI with QCA guidance (763; mean [SD] age, 64.1 [9.9] years; 574 males [75.2%]) or IVUS guidance (765; mean [SD] age, 64.6 [9.5] years; 622 males [81.3%]). The post-PCI mean (SD) minimum lumen diameter was similar between the QCA- and IVUS-guided PCI groups (2.57 [0.55] vs 2.60 [0.58] mm, P = .26). Target lesion failure at 12 months occurred in 29 of 763 patients (3.81%) in the QCA-guided PCI group and 29 of 765 patients (3.80%) in the IVUS-guided PCI group (absolute risk difference, 0.01 percentage points [95% CI, -1.91 to 1.93 percentage points]; hazard ratio, 1.00 [95% CI, 0.60-1.68]; P = .99). There was no difference in the rates of stent edge dissection (1.2% vs 0.7%, P = .25), coronary perforation (0.2% vs 0.4%, P = .41), or stent thrombosis (0.53% vs 0.66%, P = .74) between the QCA- and IVUS-guided PCI groups. The risk of the primary end point was consistent regardless of subgroup, with no significant interaction.

Conclusions and Relevance

Findings of this randomized clinical trial indicate that QCA and IVUS guidance during PCI showed similar rates of target lesion failure at 12 months. However, due to the lower-than-expected rates of target lesion failure in this trial, the findings should be interpreted with caution.

Trial Registration

ClinicalTrials.gov Identifier: NCT02978456.

Impact of Target Lesion Revascularization on Long-Term Mortality After Percutaneous Coronary Intervention for Left Main Disease

BACKGROUND

Although target lesion revascularization (TLR) after percutaneous coronary intervention (PCI) for unprotected left main coronary artery (LMCA) disease is not rare, its timing of occurrence and prognostic impact on long-term mortality is uncertain.

OBJECTIVES

This study sought to investigate TLR incidence over time and its impact on mortality after PCI with drug-eluting stents (DES) for LMCA disease.

METHODS

Using a pooled data from 4 multicenter observational registries (IRIS-DES [Interventional Cardiology Research Incorporation Society-Drug-Eluting Stents], IRIS-MAIN [Interventional Cardiology Research Incorporation Society-Left MAIN Revascularization], MAIN-COMPARE [Revascularization for Unprotected Left Main Coronary Artery Stenosis: Comparison of Percutaneous Coronary Angioplasty Versus Surgical Revascularization], and PRECOMBAT [PREmier of Randomized COMparison of Bypass Surgery versus AngioplasTy Using Drug-Eluting Stent in Patients with Left Main Coronary Artery Disease]), we evaluated 1,397 patients with LMCA disease treated with DES and available long-term mortality data. The association between TLR and the 10-year risk of mortality was examined by multivariable Cox proportional hazards regression, with TLR as a time-varying covariate.

RESULTS

During maximum follow-up of 10 years (median 6.8 years), TLR occurred in 118 patients and its 10-year cumulative incidence was 10.8%. TLR mostly occurred within 2 years after initial PCI and decreased over time: early-stage TLR (within 2 years) in 73 (61.9%) patients and late-stage TLR (beyond 2 years) in 45 (38.1%) patients. Among all TLR patients, 23 patients underwent coronary artery bypass grafting and 95 underwent repeat PCI. In the time-varying multivariable Cox model, the presence of TLR was not significantly associated with an increased risk of mortality (adjusted HR: 0.90; 95% CI: 0.50-1.63; P = 0.73).

CONCLUSIONS

Although the incidence of ischemia-driven TLR was mostly common within 2 years after left main PCI, TLR occurred steadily during the 10-year follow-up period. However, given that such patients were optimally revascularized, the prognostic impact of TLR on mortality was not substantial. (Evaluation of the First, Second, and New Drug-Eluting Stents in Routine Clinical Practice [IRIS-DES]; NCT01186133; Observational Study for Left Main Disease Treatment [IRIS-MAIN]; NCT01341327; Ten-Year Outcomes of Stents Versus Coronary-Artery Bypass Grafting for Left Main Coronary Artery Disease [MAIN COMPARE]; NCT02791412; Bypass Surgery Versus Angioplasty Using Sirolimus-Eluting Stent in Patients With Left Main Coronary Artery Disease [PRECOMBAT]; NCT00422968).

Selective ensemble methods for deep learning segmentation of major vessels in invasive coronary angiography

BACKGROUND

Invasive coronary angiography (ICA) is a primary imaging modality that visualizes the lumen area of coronary arteries for diagnosis and interventional guidance. In the current practice of quantitative coronary analysis (QCA), semi-automatic segmentation tools require labor-intensive and time-consuming manual correction, limiting their application in the catheterization room.

PURPOSE

This study aims to propose rank-based selective ensemble methods that improve the segmentation performance and reduce morphological errors that limit fully automated quantification of coronary artery using deep-learning segmentation of ICA.

METHODS

Two selective ensemble methods proposed in this work integrated the weighted ensemble approach with per-image quality estimation. The segmentation outcomes from five base models with different loss functions were ranked either by mask morphology or estimated dice similarity coefficient (DSC). The final output was determined by imposing different weights according to the ranks. The ranking criteria based on mask morphology were formulated from empirical insight to avoid frequent types of segmentation errors (MSEN), while the estimation of DSCs was performed by comparing the pseudo-ground truth generated from a meta-learner (ESEN). Five-fold cross-validation was performed with the internal dataset of 7426 coronary angiograms from 2924 patients, and prediction model was externally validated with 556 images of 226 patients.

RESULTS

The selective ensemble methods improved the segmentation performance with DSCs up to 93.07% and provided a better delineation of coronary lesion with local DSCs of up to 93.93%, outperforming all individual models. Proposed methods also minimized the chances of mask disconnection in the most narrowed regions to 2.10%. The robustness of the proposed methods was also evident in the external validation. Inference time for major vessel segmentation was approximately one-sixth of a second.

CONCLUSION

Proposed methods successfully reduced morphological errors in the predicted masks and were able to enhance the robustness of the automatic segmentation. The results suggest better applicability of real-time QCA-based diagnostic methods in routine clinical settings.

Machine Learning-Based prediction of Post-Treatment ambulatory blood pressure in patients with hypertension

Purpose. Pre-treatment prediction of individual blood pressure (BP) response to anti-hypertensive medication is important to determine the specific regimen for promptly and safely achieving a target BP. This study aimed to develop supervised machine learning (ML) models for predicting patient-specific treatment effects using 24-hour ambulatory BP monitoring (ABPM) data.Materials and Methods. A total of 1,129 patients who had both baseline and follow-up ABPM data were randomly assigned into training, validation and test sets in a 3:1:1 ratio. Utilising the features including clinical and laboratory findings, initial ABPM data, and anti-hypertensive medication at baseline and at follow-up, ML models were developed to predict post-treatment individual BP response. Each case was labelled by the mean 24-hour and daytime BPs derived from the follow-up ABPM.Results. At baseline, 616 (55%) patients had been treated using mono or combination therapy with 45 anti-hypertensive drugs and the remaining 513 (45%) patients had been untreated (drug-naïve). By using CatBoost, the difference between predicted vs. measured mean 24-hour systolic BP at follow-up was 8.4 ± 7.0 mm Hg (% difference of 6.6% ± 5.7%). The difference between predicted vs. measured mean 24-hour diastolic BP was 5.3 ± 4.3 mm Hg (% difference of 6.8% ± 5.5%). There were significant correlations between the CatBoost-predicted vs. the ABPM-measured changes in the mean 24-hour Systolic (r = 0.74) and diastolic (r = 0.68) BPs from baseline to follow-up. Even in the patients with renal insufficiency or diabetes, the correlations between CatBoost-predicted vs. ABPM-measured BP changes were significant.Conclusion. ML algorithms accurately predict the post-treatment ambulatory BP levels, which may assist clinicians in personalising anti-hypertensive treatment.

Age- and Sex-Specific Disparities in Outcomes After Ticagrelor Versus Clopidogrel in East Asian Patients

It is unknown whether there are age- and gender-related differences in the safety and efficacy of potent P2Y12 inhibitors in East Asian populations with a different bleeding or ischemic propensity. Using data from the TICAKOREA (Ticagrelor Versus Clopidogrel in Asian/Korean Patients with ACS Intended for Invasive Management) trial comparing ticagrelor versus clopidogrel for 800 Korean patients with acute coronary syndrome, the safety and efficacy outcomes were compared according to age (<75 vs ≥75 years) and gender (men vs women). The primary bleeding end point was clinically significant bleeding, and the primary ischemic end point was a major adverse cardiovascular event (MACE) at 12 months. The incidences of clinically significant bleeding were significantly higher after ticagrelor than after clopidogrel in patients aged <75 years (adjusted hazard ratio [HR] 2.56, 95% confidence interval [CI] 1.40 to 4.67) but not in patients aged ≥75 years (adjusted HR 1.1, 95% CI 0.40 to 3.38). The incidences of MACEs were significantly higher after ticagrelor than after clopidogrel in patients aged ≥75 years (adjusted HR 6.14, 95% CI 1.40 to 26.90) but not in patients aged <75 years (adjusted HR 0.93, 95% CI 0.50 to 1.73). The incidences of clinically significant bleeding were significantly higher after ticagrelor than after clopidogrel in men (adjusted HR 2.69, 95% CI 1.38 to 5.24) but not in women (adjusted HR 1.49, 95% CI 0.64 to 3.46). The adjusted risks of MACEs after ticagrelor or clopidogrel were not significantly different between men and women. In conclusion, there were substantial age- and gender-related differences in bleeding and ischemic outcomes after ticagrelor or clopidogrel in Korean patients with acute coronary syndrome. Clinical Trial Registration: URL: https://www.clinicaltrials.gov Unique identifier: NCT02094963.

Early left atrial venting versus conventional treatment for left ventricular decompression during venoarterial extracorporeal membrane oxygenation support: The EVOLVE-ECMO randomized clinical trial

AIMS

Few studies have reported data on the optimal timing of left ventricular (LV) unloading during venoarterial extracorporeal membrane oxygenation (VA-ECMO) for cardiac arrest or shock. This study evaluated the feasibility of an early LV unloading strategy compared with a conventional strategy in VA-ECMO.

METHODS AND RESULTS

Between December 2018 and August 2022, 60 patients at two institutions were randomized in a 1:1 ratio to receive early (n = 30) or conventional (n = 30) LV unloading strategies. The early LV unloading strategy was defined as LV unloading performed at the time of VA-ECMO insertion. LV unloading was performed using a percutaneous transseptal left atrial cannulation via the femoral vein incorporated into the ECMO venous circuit. The early and conventional LV unloading groups included 29 (96.7%) and 23 (76.7%) patients, respectively (median time from VA-ECMO insertion to LV unloading: 48.4 h, interquartile range 47.8-96.5 h). The groups showed no significant differences in the rate of VA-ECMO weaning as the primary endpoint (70.0% vs. 76.7%; relative risk 0.91; 95% confidence interval 0.67-1.24; p = 0.386) and survival to discharge (53.3% vs. 50.0%, p = 0.796). However, the pulmonary congestion score index at 48 h after LV unloading was significantly improved only in the early LV unloading group (2.0 ± 0.7 vs. 1.7 ± 0.6 at baseline vs. at 48 h; p = 0.008).

CONCLUSIONS

Compared with the conventional approach, early LV unloading did not improve the VA-ECMO weaning rate, despite the rapid improvement in pulmonary congestion. Therefore, the results of this study do not support the application of this strategy after VA-ECMO insertion.

Preventive PCI or medical therapy alone for vulnerable atherosclerotic coronary plaque: Rationale and design of the randomized, controlled PREVENT trial

BACKGROUND

Acute coronary syndromes are commonly caused by the rupture of vulnerable plaque, which often appear angiographically not severe. Although pharmacologic management is considered standard therapy for stabilizing plaque vulnerability, the potential role of preventive local treatment for vulnerable plaque has not yet been determined. The PREVENT trial was designed to compare preventive percutaneous coronary intervention (PCI) plus optimal medical therapy (OMT) with OMT alone in patients with functionally nonsignificant high-risk vulnerable plaques.

METHODS

The PREVENT trial is a multinational, multicenter, prospective, open-label, active-treatment-controlled randomized trial. Eligible patients have at least 1 angiographically significant stenosis (diameter stenosis >50% by visual estimation) without functional significance (fractional flow reserve [FFR] >0.80). Target lesions are assessed by intracoronary imaging and must meet at least 2 imaging criteria for vulnerable plaque; (1) minimal lumen area <4.0 mm2; (2) plaque burden >70%; (3) maximal lipid core burden index in a 4 mm segment >315 by near infrared spectroscopy; and (4) thin cap fibroatheroma as determined by virtual histology or optical coherence tomography. Enrolled patients are randomly assigned in a 1:1 ratio to either preventive PCI with either bioabsorbable vascular scaffolds or metallic everolimus-eluting stents plus OMT or OMT alone. The primary endpoint is target-vessel failure, defined as the composite of death from cardiac causes, target-vessel myocardial infarction, ischemic-driven target-vessel revascularization, or hospitalization for unstable or progressive angina, at 2 years after randomization.

RESULTS

Enrollment of a total of 1,608 patients has been completed. Follow-up of the last enrolled patient will be completed in September 2023 and primary results are expected to be available in early 2024.

CONCLUSIONS

The PREVENT trial is the first large-scale, randomized trial to evaluate the effect of preventive PCI on non-flow-limiting vulnerable plaques containing multiple high-risk features that is appropriately powered for clinical outcomes. PREVENT will provide compelling evidence as to whether preventive PCI of vulnerable plaques plus OMT improves patient outcomes compared with OMT alone.

CLINICAL TRIAL REGISTRATION

URL: https://www.

CLINICALTRIALS

gov. Unique identifier: NCT02316886.

KEY POINTS

The PREVENT trial is the first, large-scale randomized clinical trial to evaluate the effect of preventive PCI on non-flow-limiting vulnerable plaque with high-risk features. It will provide compelling evidence to determine whether PCI of focal vulnerable plaques on top of OMT improves patient outcomes.

Ten-year prognostic value of coronary CT angiography in asymptomatic patients with type 2 diabetes

INTRODUCTION AND OBJECTIVES

The United Kingdom Prospective Diabetes Study (UKPDS) risk score has limited value for predicting coronary artery disease (CAD) events. We investigated the additive value of coronary computed tomography angiography (CCTA) on top of the UKPDS risk score in predicting 10-year adverse cardiac events in asymptomatic patients with type 2 diabetes.

METHODS

We evaluated 589 asymptomatic diabetic patients without a history of CAD who underwent CCTA. The primary outcome was a composite of cardiac death, nonfatal myocardial infarction, unstable angina requiring hospitalization, and revascularization. We estimated the discrimination and reclassification ability for the prediction models, which included combinations of the UKPDS category, severity of stenosis, and coronary artery calcium score by CCTA.

RESULTS

The incidence of the primary outcome was 12.4%. During 10 years of follow-up, patients without plaque by CCTA tended to have a low CAD event rate, while those with obstructive CAD tended to have a high event rate, irrespective of the baseline UKPDS risk category. The model that included only the UKPDS category had a Harrell's c-index of 0.658; adding the degree of stenosis to the model significantly increased the c-index by 0.066 (P=.004), while adding coronary artery calcium score increased the c-index by only 0.039 (P=.056). Overall, CCTA information in addition to the UKPDS risk category improved the reclassification rate for predicting the primary outcome.

CONCLUSIONS

In asymptomatic patients with type 2 diabetes, CCTA information for CAD provided significant incremental discriminatory power beyond the UKPDS risk score category for predicting 10-year adverse coronary events.

Effect of rosuvastatin 20 mg versus rosuvastatin 5 mg plus ezetimibe on statin side-effects in elderly patients with atherosclerotic cardiovascular disease: Rationale and design of a randomized, controlled SaveSAMS trial

BACKGROUND

Current guidelines recommend that patients with established atherosclerotic cardiovascular disease (ASCVD) use high-intensity statin therapy to lower low-density lipoprotein (LDL)-cholesterol levels by at least 50%, irrespective of age. However, in real-world practice, there is reluctance to maintain statin use in response to side-effects, particularly statin-associated muscle symptoms (SAMS). Moreover, no randomized trial has been conducted on the safety of statin therapy in elderly patients.

TRIAL DESIGN

This investigator-initiated, multicenter, randomized clinical trial aimed to investigate the incidence of SAMS and its effect on LDL-cholesterol levels in elderly patients with established ASCVD. Eligible patients were aged 70 years or older with established ASCVD. Consecutive patients who met the inclusion criteria were randomized in a 1:1 fashion to receive either intensive statin monotherapy (rosuvastatin 20 mg) or combination therapy (rosuvastatin/ezetimibe, 5/10 mg). The primary endpoint of the study is SAMS at 6 months with regard to treatment strategy. Positive SAMS results are defined as patients with a proposed statin myalgia index score of 7 or higher. The key secondary end-points are target LDL-cholesterol achievement (LDL < 70 mg/dL), incidence of myopathy, rhabdomyolysis, frequency of drug discontinuation, and creatinine kinase, aspartate transaminase, alanine transaminase, total cholesterol, LDL-cholesterol, high-density lipoprotein-cholesterol, triglyceride, and highly sensitive C-reactive protein levels at 6 months.

CONCLUSIONS

The SaveSAMS study is a multicenter, randomized trial that will compare the incidence of SAMS in patients with established ASCVD who are 70 years or older on intensive statin monotherapy to that combination therapy.

Validation of Academic Research Consortium for High Bleeding Risk Definition in East-Asian Patients

Background

Clinical applicability of the Academic Research Consortium High Bleeding Risk (ARC-HBR) criteria in East-Asian patients receiving potent antiplatelet therapy for acute coronary syndromes (ACS) is still undetermined.

Objectives

The purpose of this study was to validate the ARC definition for HBR in East-Asian patients with ACS for invasive management.

Methods

We analyzed data from the TICAKOREA (Ticagrelor Versus Clopidogrel in Asian/Korean Patients With ACS Intended for Invasive Management) trial and randomly assigned 800 Korean ACS subjects to receive, in a 1:1 ratio, ticagrelor or clopidogrel. Patients were considered HBR if they met at least 1 major or 2 minor ARC-HBR criteria. The primary bleeding endpoint was Bleeding Academic Research Consortium 3 or 5 bleeding and the primary ischemic endpoint was a major adverse cardiovascular event (MACE) (a composite of cardiovascular death, myocardial infarction, or stroke) at 12 months.

Results

Among 800 randomized patients, 129 (16.3%) were categorized HBR patients. HBR patients, compared with non-HBR patients, had a higher incidence of Bleeding Academic Research Consortium 3 or 5 bleeding (10.0% vs 3.7%; HR: 2.98; 95% CI: 1.52-5.86; P < 0.001) and MACE (14.3% vs 6.1%; HR: 2.35; 95% CI: 1.35-4.10; P = 0.002). The relative treatment effect of ticagrelor or clopidogrel on primary bleeding and ischemic outcomes were different between each group.

Conclusions

This study validates the ARC-HBR definition in Korean ACS patients. Approximately 15% of patients qualified as HBR patients who were at increased risk not only for bleeding but also for thrombotic events. The clinical application of ARC-HBR to determine the relative effect of different antiplatelet regiments should be further investigated. (Safety and Efficacy of Ticagrelor Versus Clopidogrel in Asian/KOREAn Patients with Acute Coronary Syndromes Intended for Invasive Management [TICA KOREA]; NCT02094963).

Myocardial Scar and Revascularization on Mortality in Ischemic Cardiomyopathy (from the Late Gadolinium Enhancement Cardiac Magnetic Resonance Study)

Myocardial viability test to guide revascularization remains uncertain in patients with ischemic cardiomyopathy. We evaluated the different impacts of revascularization on cardiac mortality according to the extent of myocardial scar assessed by cardiac magnetic resonance (CMR) with late gadolinium enhancement (LGE) in patients with ischemic cardiomyopathy. A total of 404 consecutive patients with significant coronary artery disease and an ejection fraction ≤35% were assessed by LGE-CMR before revascularization. Of them, 306 patients underwent revascularization and 98 patients received medical treatment alone. The primary outcome was cardiac death. During a median follow-up of 6.3 years, cardiac death occurred in 158 patients (39.1%). Revascularization was associated with a significantly lower risk of cardiac death than medical treatment alone in the overall population (adjusted hazard ratio [aHR] 0.29, 95% confidence interval (CI) 0.19 to 0.45, p <0.001). There was a significant interaction between the number of segments with >75% transmural LGE and revascularization on the risk of cardiac death (p = 0.037 for interaction). In patients with limited myocardial scar (<6 segments with >75% transmural LGE, n = 354), revascularization had a significantly lower risk of cardiac death than medical treatment alone (aHR 0.24, 95% CI 0.15 to 0.37, p <0.001); in patients with extensive myocardial scar (≥6 segments with >75% transmural LGE, n = 50), there was no significant difference between revascularization and medical treatment alone regarding the risk of cardiac death (aHR 1.33, 95% CI 0.46 to 3.80, p = 0.60). In conclusion, the assessment of myocardial scar by LGE-CMR may be helpful in the decision-making process for revascularization in patients with ischemic cardiomyopathy.

Impact of Complete or Incomplete Revascularization for Left Main Coronary Disease: The Extended PRECOMBAT Study

Background

Whether complete revascularization (CR) or incomplete revascularization (IR) may affect long-term outcomes after PCI) and coronary artery bypass grafting (CABG) for left main coronary artery (LMCA) disease is unclear.

Objectives

The authors sought to assess the impact of CR or IR on 10-year outcomes after PCI or CABG for LMCA disease.

Methods

In the PRECOMBAT (Premier of Randomized Comparison of Bypass Surgery versus Angioplasty Using Sirolimus-Eluting Stent in Patients with Left Main Coronary Artery Disease) 10-year extended study, the authors evaluated the effect of PCI and CABG on long-term outcomes according to completeness of revascularization. The primary outcome was the incidence of major adverse cardiac or cerebrovascular events (MACCE) (composite of mortality from any cause, myocardial infarction, stroke, or ischemia-driven target vessel revascularization).

Results

Among 600 randomized patients (PCI, n = 300 and CABG, n = 300), 416 patients (69.3%) had CR and 184 (30.7%) had IR; 68.3% of PCI patients and 70.3% of CABG patients underwent CR, respectively. The 10-year MACCE rates were not significantly different between PCI and CABG among patients with CR (27.8% vs 25.1%, respectively; adjusted HR: 1.19; 95% CI: 0.81-1.73) and among those with IR (31.6% vs 21.3%, respectively; adjusted HR: 1.64; 95% CI: 0.92-2.92) (P for interaction = 0.35). There was also no significant interaction between the status of CR and the relative effect of PCI and CABG on all-cause mortality, serious composite of death, myocardial infarction, or stroke, and repeat revascularization.

Conclusions

In this 10-year follow-up of PRECOMBAT, the authors found no significant difference between PCI and CABG in the rates of MACCE and all-cause mortality according to CR or IR status. (Ten-Year Outcomes of PRE-COMBAT Trial [PRECOMBAT], NCT03871127; PREmier of Randomized COMparison of Bypass Surgery Versus AngioplasTy Using Sirolimus-Eluting Stent in Patients With Left Main Coronary Artery Disease [PRECOMBAT], NCT00422968).

Ticagrelor Versus Clopidogrel in East Asian Patients With Acute Coronary Syndrome and Diabetes Mellitus

BACKGROUND

It is still unknown whether diabetes mellitus (DM) affects the relative safety and efficacy of ticagrelor vs clopidogrel in East Asian patients with acute coronary syndrome (ACS).

OBJECTIVES

The authors sought to assess the safety and efficacy of ticagrelor vs clopidogrel according to the diabetic status of East Asian patients with ACS undergoing invasive management.

METHODS

This prespecified analysis of the TICA KOREA (Clinically Significant Bleeding With Ticagrelor Versus Clopidogrel in Korean Patients With Acute Coronary Syndromes Intended for Invasive Management) trial included 800 Korean patients. The primary safety endpoint was clinically significant bleeding (PLATO [Platelet Inhibition and Clinical Outcomes] major or minor bleeding) at 12 months; the efficacy endpoint was major adverse cardiovascular events (cardiovascular death, myocardial infarction, and stroke).

RESULTS

Of 800 patients, 216 (27.0%) had DM. The incidence of clinically significant bleeding within 12 months was significantly higher with ticagrelor than clopidogrel in the nondiabetic group (10.2% vs 4.3%; HR: 2.45; 95% CI: 1.27-4.70; P = 0.007) and tended to be higher in the diabetic group (13.8% vs 8.0%; HR: 1.87; 95% CI: 0.54-4.36; P = 0.15); there was no significant interaction between treatment-arm and DM (P for interaction = 0.64). The incidences of major adverse cardiovascular events were not significantly different after ticagrelor or clopidogrel both in the diabetic group (10.8% vs 6.0%; HR: 1.90; 95% CI: 0.71-5.07; P = 0.20) and in the nondiabetic group (8.5% vs 5.7%; HR: 1.51; 95% CI: 0.81-2.81; P = 0.19) without significant interaction (P-for-interaction = 0.71).

CONCLUSIONS

In Korean ACS patients undergoing early invasive management, diabetes status did not affect the relative safety and efficacy of ticagrelor and clopidogrel. (Safety and Efficacy of Ticagrelor Versus Clopidogrel in Asian/Korean Patients With Acute Coronary Syndromes Intended for Invasive Management [TICA KOREA]; NCT02094963).

Association of Atrial Septal Aneurysm and Shunt Size With Stroke Recurrence and Benefit From Patent Foramen Ovale Closure

Importance

The Patent Foramen Ovale (PFO)-Associated Stroke Causal Likelihood classification system combines information regarding noncardiac patient features (vascular risk factors, infarct topography) and PFO features (shunt size and presence of atrial septal aneurysm [ASA]) to classify patients into 3 validated categories of responsiveness to treatment with PFO closure. However, the distinctive associations of shunt size and ASA, alone and in combination, have not been completely delineated.

Objective

To evaluate the association of PFO closure with stroke recurrence according to shunt size and/or the presence of an ASA.

Design, Setting, and Participants

Pooled individual patient data from 6 randomized clinical trials conducted from February 2000 to October 2017 that compared PFO closure with medical therapy. Patients in North America, Europe, Australia, Brazil, and South Korea with PFO-associated stroke were included. Analysis was completed in January 2022.

Exposures

Transcatheter PFO closure plus antithrombotic therapy vs antithrombotic therapy alone, stratified into 4 groups based on the combination of 2 features: small vs large PFO shunt size and the presence or absence of an ASA.

Main Outcomes and Measures

Recurrent ischemic stroke.

Results

A total of 121 recurrent ischemic strokes occurred in the pooled 3740 patients (mean [SD] age, 45 [10] years; 1682 [45%] female) during a median (IQR) follow-up of 57 (23.7-63.8) months. Treatment with PFO closure was associated with reduced risk for recurrent ischemic stroke (adjusted hazard ratio [aHR], 0.41 [95% CI, 0.28-0.60]; P < .001). The reduction in hazard for recurrent stroke was greater for patients with both a large shunt and an ASA (aHR, 0.15 [95% CI, 0.06-0.35]) than for large shunt without ASA (aHR, 0.27 [95% CI, 0.14-0.56]), small shunt with ASA (aHR, 0.36 [95% CI, 0.17-0.78]), and small shunt without ASA (aHR, 0.68 [95% CI, 0.41-1.13]) (interaction P = .02). At 2 years, the absolute risk reduction of recurrent stroke was greater (5.5% [95% CI, 2.7-8.3]) in patients with large shunt and ASA than for patients in the other 3 categories (1.0% for all).

Conclusions and Relevance

Patients with both a large shunt and an ASA showed a substantially greater beneficial association with PFO closure than patients with large shunt alone, patients with small shunt and ASA, and patients with neither large shunt nor ASA. These findings, combined with other patient features, may inform shared patient-clinician decision-making.

Intravascular ultrasound-guided optimization for chronic total occlusion-percutaneous coronary intervention with multiple drug-eluting stents

Background

Multiple stenting in the chronic total occlusion (CTO) lesions is frequently required, however associated with poorer clinical outcomes. It is demonstrated that intravascular ultrasound (IVUS)-guided CTO-percutaneous coronary intervention (PCI) is related to a lower risk of adverse clinical events.

Purpose

We aimed to evaluate the clinical impact of stent optimization under IVUS guidance for multiple stenting, comparing with single stenting.

Methods

A total of 916 patients receiving drug-eluting stent (DES) under IVUS guidance were classified into two groups (stent optimization and non-optimization) according to optimization criteria (an absolute expansion criteria; minimal stent area ≥4.9 mm2 and a relative expansion criteria; 80% of mean reference lumen area). Of total population, 314 patients (34.3%) were treated with single stent and 575 patients (62.7%) were treated with multiple stents, respectively. Ischemic-driven target-lesion revascularization (TLR)/reocclusion was evaluated.

Results

Under IVUS guidance, 316 patients (34.5%) met IVUS criteria for stent optimization The achieving rates were 53% in the single stent group and 24% in the multiple stents group, respectively, (p&lt;0.001). During a median of 4.7 years, the multiple stent group showed a significantly higher TLR/reocclusion rate, compared with the single stent group (12.8% vs. 5.2%, adjusted hazard ratio [HR] 2.51, 95% confidence interval [CI] 1.20–5.25, p=0.01). (Figure 1) Meeting both the absolute and relative expansion criteria was associated with a significantly low rate of TLR/reocclusion rate (12.5% vs. 5.2%, adjusted HR 0.34, 95% CI: 0.15–0.79, p=0.01). Under IVUS-guidance, there was no significant difference between multiple stenting and single stenting in case of achieving the optimization criteria (6.5% vs. 4.2%, p=0.11), whereas non-optimization group in the patients with multiple stenting showed a significantly higher rate of TLR/reocclusion, compared with IVUS-optimization group in the patients with single stenting (14.5% vs. 4.2%, p=0.002). (Figure 2)

Conclusions

In CTO-PCI with DES, multiple stenting significantly increased the risk of TLR/reocclusion. IVUS-guided optimization for multiple stenting showed a comparable long-term risk of TLR/reocclusion to single stenting with IVUS optimization. Hence, achieving IVUS expansion criteria may help to reduce the risk of TLR/reocclusion in CTO-PCI with multiple DES overlapping.

Funding Acknowledgement

Type of funding sources: None.

Incidence and predictors of intracranial bleeding after coronary artery bypass graft surgery

Background

There is a paucity of direct data on the incidence and predictors of intracranial bleeding (ICB) after coronary artery bypass graft surgery (CABG).

Methods

The Korean National Health Insurance database was used to identify patients without prior ICB who underwent CABG. The outcomes of interest were the time-dependent incidence rates of ICB and the associated mortality.

Results

Among 35,021 patients who underwent CABG between 2007 and 2018, 895 (2.6%) experienced an ICB during a median follow-up of 6.0 years. The 1-year cumulative incidence of ICB was 0.76%, with a relatively high incidence rate (9.93 cases per 1,000 person-years) within the first 1–30 days. Subsequent incidence rates showed a sharp decline until 3 years, followed by a steady decrease up to 10 years. The 1-year mortality rate after ICB was 38.1%, with most deaths occurring within 30 days (23.6%). The predictors of ICB after CABG were age ≥ 75 years, hypertension, pre-existing dementia, history of ischemic stroke or transient ischemic attack, and end-stage renal disease.

Conclusions

In an unselected nationwide population undergoing CABG, the incidence of ICB was non-negligible and showed a relatively high incidence rate during the early postoperative period. Post-CABG ICB was associated with a high risk of premature death. Further research is needed to stratify high-risk patients and personalize therapeutic decisions for preventing ICB after CABG.

Transcatheter versus surgical closure of atrial septal defect in adult patients with tricuspid regurgitation

OBJECTIVES

Transcatheter closure using a device has been established as an effective atrial septal defect (ASD) treatment, but its value in treating patients with concomitant functional tricuspid regurgitation (TR) is relatively unknown. We sought to evaluate outcomes of patients with ASD and significant TR after transcatheter ASD closure or surgical treatment.

METHODS

A total of 252 consecutive adult patients (53.8±13.8 years, 180 females) who had a significant functional TR before ASD closure were retrospectively analysed. The primary end point was a composite of all-cause death, stroke and heart failure. The secondary end point was significant residual TR early and at 1 year after ASD closure.

RESULTS

Transcatheter ASD closure alone and surgical ASD closure along with tricuspid annuloplasty (TAP) were performed in 68 and 184 patients, respectively. Significant TR remained in 32% (81/252) early after ASD closure and in 29% (52/182) after 1 year. The severity of TR was significantly decreased after transcatheter ASD closure (p<0.001). In multivariable analysis, TAP (OR 0.07; p<0.001) and ASD diameter (OR 0.90; p=0.040) were independent predictors of the significant residual TR early after treatment, while only TAP (OR 0.08; p<0.001) was a significant predictor at 1 year after treatment. After propensity score matching in patients with moderate or severe TR, there were no significant differences between the transcatheter ASD closure group and surgical ASD closure plus TAP group in terms of the event rates at 5 years (10.3% vs 5.5%, p=0.963).

CONCLUSIONS

While TAP was effective for the treatment of significant TR, transcatheter ASD closure also significantly reduced TR as well. Transcatheter ASD closure may be considered an alternative treatment option in patients with moderate or severe TR.

Comparison of Contemporary Drug-Eluting Stents in Patients Undergoing Complex High-Risk Indicated Procedures

BACKGROUND

Limited data are available on the relative performances of diverse contemporary drug-eluting stents (DES) in patients undergoing complex high-risk indicated procedures (CHIP).

OBJECTIVES

The purpose of this study was to evaluate the comparative effectiveness of contemporary second-generation DES for CHIP patients in "real-world" settings.

METHODS

Of 28,843 patients enrolled in the IRIS-DES registry, a total of 6,645 patients with CHIP characteristics who received 5 different types of contemporary DES were finally included: 3,752 with cobalt-chromium everolimus-eluting stents (CoCr-EES), 1,258 with Resolute zotarolimus-eluting stents (Re-ZES), 864 with platinum-chromium EES (PtCr-EES), 437 with ultrathin strut biodegradable-polymer sirolimus-eluting stents (UT-SES), and 334 with bioresorbable polymer SES (BP-SES). The primary outcome was target-vessel failure (a composite of cardiac death, target-vessel myocardial infarction, and target-vessel revascularization) at 12 months.

RESULTS

At 12 months, the rate of target-vessel failure was highest in the CoCr-EES (7.1%) group; intermediate in the Re-ZES (5.0%), PtCr-EES (4.6%), and BP-SES (4.2%) groups; and lowest in the UT-SES (3.8%) group (overall long-rank P = 0.001). In multiple-treatment propensity-score analysis, the adjusted hazard ratios (HRs) for target-vessel failure were significantly lower in the Re-ZES (HR: 0.71; 95% confidence interval [CI]: 0.52-0.97), the UT-SES (HR: 0.52; 95% CI: 0.29-0.95), and BP-SES (HR: 0.33; 95% CI: 0.16-0.70) groups than in the CoCr-EES group (referent).

CONCLUSIONS

In this contemporary PCI registry, we observed the differential risks of target-vessel failure according to various types of contemporary DES in patients with CHIP characteristics. However, owing to inherent selection bias, the results should be considered hypothesis-generating, highlighting the need for further randomized trials. (Evaluation of the First, Second, and New Drug-Eluting Stents in Routine Clinical Practice [IRIS-DES]; NCT01186133).

Time-Dependent Impact of Sex on the Long-Term Outcomes After Left Main Revascularization

Background

There are still limited data about the differential effect of sex on long‐term outcomes after percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) for left main coronary artery disease. This extended follow‐up study of the MAIN‐COMPARE (Ten‐Year Outcomes of Stents Versus Coronary‐Artery Bypass Grafting for Left Main Coronary Artery Disease) registry evaluated clinical outcomes beyond 10 years.

Methods and Results

Of 2240 patients with unprotected left main coronary artery disease (PCI=1102 and CABG=1138), all‐cause mortality, the composite of death, Q‐wave myocardial infarction, or stroke, and target vessel revascularization were separately evaluated in both sexes. Of 2240 patients, 631 (28.2%) were women and 1609 (71.8%) were men. Women had lower 10‐year incidences of death and serious composite outcomes than men. The adjusted 10‐year risks of adverse outcomes were similar in men. However, the adjusted 10‐year risks were different according to a prespecified period in women. In the short‐term (0–1 year) period, PCI had a significantly lower risk for serious composite outcomes (adjusted hazard ratio [HR], 0.41; 95% CI, 0.19–0.91; P=0.03) compared with CABG. The adjusted risks for death and serious composite outcomes were significantly higher after PCI than after CABG, during the midterm (1–5 years) period (death; adjusted HR, 3.99; 95% CI, 2.01–7.92; P<0.001 and composite outcome; adjusted HR, 2.93; 95% CI, 1.59–5.39; P=0.001). Beyond 5 years, adjusted risks were similar after PCI and CABG in women.

Conclusions

In this 10‐year extended follow‐up study of patients undergoing left main coronary artery revascularization, we observed a time‐dependent impact of sex on the long‐term outcomes after PCI and CABG, especially in women, with significant interactions. However, these results warrant confirmation on larger series of studies.

Registration

URl: https://www.clinicaltrials.gov; Unique identifier: NCT02791412.

Abstract TMP106: Pooled Analysis Of Five Randomized Trials Comparing Device Closure Of Patent Foramen Ovale After Stroke To Medical Treatment: Impact Of Residual Shunt On Stroke Outcomes

Introduction: Patent foramen ovale (PFO) closure is effective for secondary stroke prevention in well selected patients. After device implantation some patients have residual shunting. There was no impact of incomplete closure on recurrent stroke risk in any of the trials but outcome rates are low with little power to detect an effect.

Hypothesis: Patients with residual shunts after PFO closure have more recurrent strokes than those with complete elimination of shunting.

Methods: We pooled individual patient data from 5 of 6 randomized clinical trials comparing medical therapy to PFO closure + medical therapy. Residual shunt data were not available for 1 trial. This analysis only includes PFO closure subjects. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated with Cox proportional hazards regression, adjusted for age, sex, coronary disease, diabetes, hypertension, hyperlipidemia, prior stroke/TIA, smoking, index event (stroke vs TIA), hypermobile septum, shunt size (large vs small) and infarct location (superficial vs deep). Multiple imputation of missing values for adjusted variables was used.

Results: Among 1475 patients treated with PFO closure and with non-missing residual shunt data, 149 (10%) had incomplete closure. The median time from procedure to shunt measurement was 204 days (25 th -75 th percentile, 181-722). In the complete closure group the primary endpoint of recurrent ischemic stroke occurred in 30 patients (2.3%; 95% CI 1.5-3.2%) compared to 4 (2.7%; 95% CI 0.7-6.7%) with incomplete closure. Unadjusted and adjusted HRs comparing incomplete vs complete closure were 1.37 (0.48, 3.92) and 1.69 (0.37, 4.95) respectively. The secondary endpoint of recurrent ischemic stroke, TIA, or vascular death occurred in 66 (5.0%; 95% CI 3.9-6.3%) patients with complete closure compared to 9 (6.0%; 95% CI 2.8-11.2%) without. Unadjusted and adjusted HRs were 1.26 (0.63, 2.54) and 1.39 (0.68, 2.83) respectively.

Conclusions: Our pooled analysis of individual subjects after PFO closure from 5 of 6 relevant randomized clinical trials, showed no association between residual shunt and recurrent stroke events. This analysis was limited by low rates of residual shunt and recurrent events even in this large, combined dataset.

Quantitative coronary angiography versus intravascular ultrasound guidance for drug-eluting stent implantation (GUIDE-DES): study protocol for a randomised controlled non-inferiority trial

INTRODUCTION

Angiography remains the gold standard for guiding percutaneous coronary intervention (PCI). However, it is prone to suboptimal stent results due to the visual estimation of coronary measurements. Although the benefit of intravascular ultrasound (IVUS)-guided PCI is becoming increasingly recognised, IVUS is not affordable for many catheterisation laboratories. Thus, a more practical and standardised angiography-based approach is necessary to support stent implantation.

METHODS AND ANALYSIS

The Quantitative Coronary Angiography versus Intravascular Ultrasound Guidance for Drug-Eluting Stent Implantation trial is a randomised, investigator-initiated, multicentre, open-label, non-inferiority trial comparing the quantitative coronary angiography (QCA)-guided PCI strategy with IVUS-guided PCI in all-comer patients with significant coronary artery disease. A novel, standardised, QCA-based PCI protocol for the QCA-guided group will be provided to all participating operators, while the PCI optimisation criteria will be predefined for both strategies. A total of 1528 patients will be randomised to either group at a 1:1 ratio. The primary endpoint is the 12-month cumulative incidence of target-lesion failure defined as a composite of cardiac death, target-vessel myocardial infarction or ischaemia-driven target-lesion revascularisation. Clinical follow-up assessments are scheduled at 1, 6 and 12 months for all patients enrolled in the study.

ETHICS AND DISSEMINATION

Ethics approval for this study was granted by the Institutional Review Board of Asan Medical Center (no. 2017-0060). Informed consent will be obtained from every participant. The study findings will be published in peer-reviewed journal articles and disseminated through public forums and academic conference presentations. Cost-effectiveness and secondary imaging analyses will be shared in secondary papers.

TRIAL REGISTRATION NUMBER

NCT02978456.

Heterogeneity of Treatment Effects in an Analysis of Pooled Individual Patient Data From Randomized Trials of Device Closure of Patent Foramen Ovale After Stroke

Importance

Patent foramen ovale (PFO)-associated strokes comprise approximately 10% of ischemic strokes in adults aged 18 to 60 years. While device closure decreases stroke recurrence risk overall, the best treatment for any individual is often unclear.

Objective

To evaluate heterogeneity of treatment effect of PFO closure on stroke recurrence based on previously developed scoring systems.

Design, Setting, and Participants

Investigators for the Systematic, Collaborative, PFO Closure Evaluation (SCOPE) Consortium pooled individual patient data from all 6 randomized clinical trials that compared PFO closure plus medical therapy vs medical therapy alone in patients with PFO-associated stroke, and included a total of 3740 participants. The trials were conducted worldwide from 2000 to 2017.

Exposures

PFO closure plus medical therapy vs medical therapy alone. Subgroup analyses used the Risk of Paradoxical Embolism (RoPE) Score (a 10-point scoring system in which higher scores reflect younger age and the absence of vascular risk factors) and the PFO-Associated Stroke Causal Likelihood (PASCAL) Classification System, which combines the RoPE Score with high-risk PFO features (either an atrial septal aneurysm or a large-sized shunt) to classify patients into 3 categories of causal relatedness: unlikely, possible, and probable.

Main Outcomes and Measures

Ischemic stroke.

Results

Over a median follow-up of 57 months (IQR, 24-64), 121 outcomes occurred in 3740 patients. The annualized incidence of stroke with medical therapy was 1.09% (95% CI, 0.88%-1.36%) and with device closure was 0.47% (95% CI, 0.35%-0.65%) (adjusted hazard ratio [HR], 0.41 [95% CI, 0.28-0.60]). The subgroup analyses showed statistically significant interaction effects. Patients with low vs high RoPE Score had HRs of 0.61 (95% CI, 0.37-1.00) and 0.21 (95% CI, 0.11-0.42), respectively (P for interaction = .02). Patients classified as unlikely, possible, and probable using the PASCAL Classification System had HRs of 1.14 (95% CI, 0.53-2.46), 0.38 (95% CI, 0.22-0.65), and 0.10 (95% CI, 0.03-0.35), respectively (P for interaction = .003). The 2-year absolute risk reduction was -0.7% (95% CI, -4.0% to 2.6%), 2.1% (95% CI, 0.6%-3.6%), and 2.1% (95% CI, 0.9%-3.4%) in the unlikely, possible, and probable PASCAL categories, respectively. Device-associated adverse events were generally higher among patients classified as unlikely; the absolute risk increases in atrial fibrillation beyond day 45 after randomization with a device were 4.41% (95% CI, 1.02% to 7.80%), 1.53% (95% CI, 0.33% to 2.72%), and 0.65% (95% CI, -0.41% to 1.71%) in the unlikely, possible, and probable PASCAL categories, respectively.

Conclusions and Relevance

Among patients aged 18 to 60 years with PFO-associated stroke, risk reduction for recurrent stroke with device closure varied across groups classified by their probabilities that the stroke was causally related to the PFO. Application of this classification system has the potential to guide individualized decision-making.

Very Long-term Safety and Effectiveness of Drug-Eluting or Bare-Metal Stents for Left Main Coronary Disease

Background

Limited data are available on the long-term outcomes of drug-eluting stents (DES) vs bare-metal stents (BMS) in patients with left main coronary artery (LMCA) disease.

Methods

In this observational cohort of the Revascularization for Unprotected Left Main Coronary Artery Stenosis: Comparison of Percutaneous Coronary Angioplasty vs Surgical Revascularization (MAIN-COMPARE) registry, we evaluated patients with unprotected LMCA stenosis who received DES or BMS between January 2000 and June 2006. The primary outcome was a composite of all-cause death or myocardial infarction (MI) at 10 years. Adjusted outcomes were compared using propensity scores and inverse probability of treatment weighting.

Results

A total of 1102 patients underwent DES (n = 784) or BMS (n = 318) during the study period. At 10 years, the adjusted rate of the primary outcome was significantly lower in DES group than in the BMS group (27.9% vs 37.0%; hazard ratio [HR], 0.71; 95% confidence interval [CI], 0.53-0.94; P = 0.02). The adjusted 10-year mortality rate was significantly lower in DES group than in the BMS group (20.6% vs 29.6%; HR, 0.65; 95% CI, 0.46-0.91; P = 0.01), whereas the 10-year rate of MI was similar between the 2 groups (9.9% vs 11.0%; HR, 0.93; 95% CI, 0.54-1.59; P = 0.78). DES use was associated with a significant reduction in the rate of target-lesion revascularization (10.2% vs 21.8%; HR, 0.41; 95% CI, 0.27-0.61; P < 0.001).

Conclusions

In this 10-year follow-up study in patients with LMCA disease, DES use was associated with a significant reduction in the rate of the composite of death or MI, mortality, and target-lesion revascularization, when compared with BMS.

Long-Term Outcomes After Percutaneous Coronary Intervention With Second-Generation Drug-Eluting Stents or Coronary Artery Bypass Grafting for Multivessel Coronary Disease

More evidence is required with respect to the comparative effectiveness of percutaneous coronary intervention (PCI) with second-generation drug-eluting stents (DESs) versus coronary artery bypass grafting (CABG) in contemporary clinical practice. This prospective observational registry-based study compared the outcomes of 6,647 patients with multivessel disease who underwent PCI with second-generation DES (n = 3,858) or CABG (n = 2,789) between January 2006 and June 2018 and for whom follow-up data were available for at least 2 to 13 years (median 4.8). The primary outcome was a composite of death, spontaneous myocardial infarction, or stroke. Baseline differences were adjusted using propensity scores and inverse probability weighting. In the overall cohort, there were no significant between-group differences in the adjusted risks for the primary composite outcome (hazard ratio [HR] for PCI vs CABG 1.03, 95% confidence interval [CI] 0.86 to 1.25, p = 0.73) and all-cause mortality (HR 0.95, 95% CI 0.76 to 1.20, p = 0.68). This relative treatment effect on the primary outcome was similar in patients with diabetes (HR 1.15, 95% CI 0.91 to 1.46, p = 0.25) and without diabetes (HR 0.95, 95% CI 0.73 to 1.22, p = 0.67) (p for interaction = 0.24). The adjusted risk of the primary outcome was significantly greater after PCI than after CABG in patients with left main involvement (HR 1.39, 95% CI 1.01 to 1.90, p = 0.044), but not in those without left main involvement (HR 0.94, 95% CI 0.76 to 1.16, p = 0.56) (p = 0.03 for interaction). In this prospective real-world long-term registry, we observed that the risk for the primary composite of death, spontaneous myocardial infarction, or stroke was similar between PCI with contemporary DES and CABG.

Ischemic Burden Assessment Using Single Photon Emission Computed Tomography in Single Vessel Chronic Total Occlusion of Coronary Artery

BACKGROUND AND OBJECTIVES

Studies evaluating the nature of ischemic burden of chronic total occlusion (CTO) vessels are still lacking.

METHODS

A total of 165 patients with single vessel CTO >2.5 mm in an epicardial coronary artery who underwent single photon emission computed tomography (SPECT) were enrolled in the study. Ischemic burden was calculated with the use of semi-quantitative SPECT analysis, and was defined as the summed difference score (SDS) divided by the maximal limit of the score (=SDS/68).

RESULTS

The mean age of the participants was 59.5 years and the CTO of the left anterior descending coronary artery (LAD), left circumplex coronary artery (LCX), and right coronary artery (RCA) accounted for 93 (56.4%), 18 (10.9%), and 54 (32.7%) patients, respectively. The median ischemic burden of the total population was 8.8%, and it was highest in the LAD CTO (10.3%) compared with the LCX (5.9%) and RCA CTO (5.9%, p<0.001). High-ischemic burden (ischemic burden >10%) was observed in 66 patients (40.0%), and in 47 patients (50.5%) of the LAD CTO. Ischemic burden was different according to the CTO location only in LAD CTO. The statistically significant predictors for high-ischemic burden were hypertension, baseline ejection fraction >45%, LAD CTO, proximal CTO location, and de novo CTO. Japanese-CTO score and Rentrop scale collateral grade were not associated with high-ischemic burden.

CONCLUSIONS

Only 40% of patients with single vessel CTO had ischemic burden >10%. For CTO vessels, measurement of ischemic burden using SPECT prior to revascularization may be helpful in identifying beneficial subjects.

Primary versus rescue retrograde approach for chronic total coronary occlusion

OBJECTIVES

We aimed to assess the advantages of using the retrograde approach as an initial strategy rather than as a rescue strategy for complex chronic total occlusions (CTOs).

BACKGROUND

Even for complex CTOs where a retrograde approach is deemed necessary, an antegrade approach is frequently used as an initial strategy in real-world practice.

METHODS

We evaluated 352 retrograde procedures for CTO conducted at our high-volume center between January 2007 and January 2019. Procedural efficiency and safety was assessed based on the guidewire manipulation time (GWMT) and the occurrence of procedure-related adverse events for the primary retrograde approach (PRA) and the rescue retrograde approach (RRA).

RESULTS

PRA and RRA were used in 191 (54.3%) and 161 (45.7%) of the CTO procedures, respectively. The complexity of the CTO lesion was significantly higher in the PRA group than in the RRA group (Japanese-CTO score, 2.62 ± 1.07 vs. 2.38 ± 1.06, p = 0.037). The technical success rate of two groups was similar (p = 0.47). The median GWMT required for PRA was significantly shorter than that for RRA (85 [interquartile range, 55-126] vs. 120 [85-157] min, p < 0.001). The total duration of the procedure and fluoroscopic time were shorter, and the number of guidewires and amount of contrast used during the index procedure were smaller in the PRA group. The incidence of procedure-related adverse events was not significantly different between the two groups.

CONCLUSIONS

PRA showed higher procedural efficiency than RRA with comparable safety. Opting for PRA for complex CTOs might be a rational decision to enhance the procedural efficiency.

Different Clinical Features between Definite and Possible Takotsubo Syndrome in a Tertiary Referral Hospital

BACKGROUND

Although imaging examination to exclude coronary artery disease (CAD) is an indispensable step for a definite diagnosis of Takotsubo syndrome (TTS), this step may be overlooked in a substantial proportion of patients with secondary TTS admitted to a tertiary hospital. However, the clinical profiles and outcomes of these patients with "possible TTS" have rarely been investigated.

METHODS

Among 420 consecutive TTS patients with characteristic transient ventricular ballooning on repeated echocardiography, 244 patients (58.1%) who underwent an imaging study for CAD were diagnosed with "definite TTS", whereas the remaining 176 were designated with "possible TTS".

RESULTS

Overall, hypoxia (67.6%) and dyspnea (55.5%) were predominant presentations. The possible group was characterized by higher prevalence of male gender (46.6% vs. 35.2%, p = 0.019), secondary TTS (97.2% vs. 86.5%, p <0.001), cancer (43.2% vs. 29.1%, p = 0.003), sepsis (46.0% vs. 32.0%, p = 0.003), and non-apical ballooning pattern (30.7% vs. 21.3%, p = 0.001) with less common ST-segment elevation on electrocardiogram (18.8% vs. 34.0%, p = 0.001). The possible group showed higher frequency of mechanical ventilation (56.2% vs. 40.2%, p = 0.001), pulmonary edema (72.2% vs. 61.5%, p = 0.023) and shock management (70.5% vs. 54.1%, p = 0.001) with similar in-hospital mortality (17.2% vs. 17.0%, p = 0.964).

CONCLUSIONS

In real-world clinical practice, coronary evaluation for strict diagnosis of TTS is not frequently feasible. Addition of the possible group without coronary evaluation to the clinical spectrum of TTS would be helpful for fair estimation of clinical implication of TTS.

Ten-year outcomes of early generation sirolimus- versus paclitaxel-eluting stents in patients with left main coronary artery disease

To compare 10-year outcomes after implantation of sirolimus-eluting stents (SES) versus paclitaxel-eluting stents (PES) for left main coronary artery (LMCA) stenosis. Very long-term outcome data of patients with LMCA disease treated with drug-eluting stents (DES) have not been well described. In 10-year extended follow-up of the MAINCOMPARE registry, we evaluated 778 patients with unprotected LMCA stenosis who were treated with SES (n = 607) or PES (n = 171) between January 2000 and June 2006. The primary composite outcome (a composite of death, myocardial infarction [MI] or target-vessel revascularization [TVR]) was compared with an inverse-probability-of-treatment-weighting (IPTW) adjustment. Clinical events have linearly accumulated over 10 years. At 10 years, there were no significant differences between SES and PES in the observed rates of the primary composite outcome (42.0% vs. 47.4%; hazard ratio [HR] 0.85; 95% confidence interval [CI] 0.66-1.10), and definite stent thrombosis (ST) (1.9% vs. 1.8%; HR 1.02, 95% CI 0.28-3.64). In the IPTW-adjusted analyses, there were no significant differences between SES and PES in the risks for the primary composite outcome (HR 0.89, 95% CI 0.65-1.14) or definite ST (adjusted HR 1.05, 95% CI 0.29-3.90). In patients who underwent DES implantation, high overall adverse clinical event rates (with a linearly increasing event rate over time) were observed during extended follow-up. At 10 years, there were no measurable differences in outcomes between patients treated with SES vs. PES for LMCA disease. The incidence of stent thrombosis was quite low and comparable between the groups.

Long-Term Clinical Impact of Intravascular Ultrasound Guidance in Stenting for Left Main Coronary Artery Disease

[Figure: see text].

Long-Term (7-Year) Clinical Implications of Newly Unveiled Asymptomatic Abnormal Ankle-Brachial Index in Patients With Coronary Artery Disease

Background The long-term impact of newly discovered, asymptomatic abnormal ankle-brachial index (ABI) in patients with significant coronary artery disease is limited. Methods and Results Between January 2006 and December 2009, ABI was evaluated in 2424 consecutive patients with no history of claudication or peripheral artery disease who had significant coronary artery disease. We previously reported a 3-year result; therefore, the follow-up period was extended. The primary end point was a composite of all-cause death, myocardial infarction (MI), and stroke over 7 years. Of the 2424 patients with significant coronary artery disease, 385 had an abnormal ABI (ABI ≤0.9 or ≥1.4). During the follow-up period, the rate of the primary outcome was significantly higher in the abnormal ABI group than in the normal ABI group (P<0.001). The abnormal ABI group had a significantly higher risk of composite of all-cause death/MI/stroke than the normal ABI group, after adjustment with multivariable Cox proportional hazards regression analysis (hazard ratio [HR], 2.07; 95% CI, 1.67-2.57; P<0.001) and propensity score-matched analysis (HR, 1.97; 95% CI, 1.49-2.60; P<0.001). In addition, an abnormal ABI was associated with a higher risk of all-cause death, MI, and stroke, but not repeat revascularization. Conclusions Among patients with significant coronary artery disease, asymptomatic abnormal ABI was associated with sustained and increased incidence of composite of all-cause death/MI/stroke, all-cause death, MI, and stroke during extended follow-up over 7 years.

Association of Lipoprotein(a) With Recurrent Ischemic Events Following Percutaneous Coronary Intervention

OBJECTIVES

This study evaluated the association between elevated levels of lipoprotein(a) [Lp(a)] and risk of recurrent ischemic events in patients who underwent percutaneous coronary intervention (PCI).

BACKGROUND

Elevated levels of Lp(a) have been identified as an independent, possibly causal, risk factor for atherosclerotic cardiovascular disease in a general population study.

METHODS

A prospective single-center registry was used to identify 12,064 patients with baseline Lp(a) measurements who underwent PCI between 2003 and 2013. The primary outcomes were a composite of cardiovascular death, spontaneous myocardial infarction, and ischemic stroke.

RESULTS

From the registry, 3,747 (31.1%) patients had high Lp(a) (>30 mg/dL) and 8,317 (68.9%) patients had low Lp(a) (≤30 mg/dL). During a median follow-up of 7.4 years, primary outcomes occurred in 1,490 patients, and the incidence rates of primary outcomes were 2.0 per 100 person-years in the high-Lp(a) group and 1.6 per 100 person-years in the low-Lp(a) group (adjusted hazard ratio [aHR]: 1.17; 95% confidence interval [CI]: 1.05-1.30; P = 0.004). Increased risk of recurrent ischemic cardiovascular events in the high-Lp(a) group was consistent in various subgroups including patients receiving statin treatment at discharge (aHR: 1.18; 95% CI: 1.03-1.34; P = 0.011). In addition, the risk of repeated revascularization was significantly higher in the high-Lp(a) group (aHR: 1.13; 95% CI: 1.02-1.25; P = 0.022).

CONCLUSIONS

Elevated levels of Lp(a) were significantly associated with the recurrent ischemic events in patients who underwent PCI. This study provides a rationale for outcome trials to test Lp(a)-lowering therapy for secondary prevention in patients undergoing PCI.

Effectiveness and Safety of Contemporary Drug-Eluting Stents in Patients With Diabetes Mellitus

BACKGROUND

Diabetes mellitus (DM) is a well-known risk factor for adverse cardiovascular events in patients receiving percutaneous coronary intervention (PCI). Limited data are available on the relative performance of different types of contemporary drug-eluting stents (DES) for diabetic patients.

OBJECTIVES

The authors investigated the effectiveness and safety profiles of several contemporary DES in patients with DM in a "real-world" clinical setting.

METHODS

Among 24,516 patients enrolled in a multicenter, prospective registry, 7,823 patients with DM were treated with 4 contemporary DES: 2,877 with a cobalt chromium everolimus-eluting stent (EES), 789 with a biodegradable polymer biolimus-eluting stent, 2,286 with a platinum chromium-EES, and 1,871 with a Resolute zotarolimus-eluting stent. The primary outcome was target vessel failure (TVF) (a composite of cardiac death, target vessel myocardial infarction, and target vessel revascularization).

RESULTS

The median follow-up duration was 2.9 years. Observed 3-year rates of TVF were not significantly different according to different DES types. On multigroup propensity-score analysis, the adjusted HRs for TVF were similar in between-group comparisons: biodegradable polymer biolimus-eluting stent (HR: 0.94; 95% CI: 0.76-1.16; P = 0.57), platinum chromium-EES (HR: 0.94; 95% CI: 0.81-1.09; P = 0.41), and Resolute zotarolimus-eluting stent (HR: 1.01; 95% CI: 0.86-1.18; P = 0.93) compared with the cobalt chromium-EES (reference). This trend was maintained in patients with non-insulin- and insulin-treated DM.

CONCLUSIONS

In this multicenter clinical-practice PCI registry, no significant between-group differences were found for a 3-year risk of TVF in patients with DM undergoing PCI with various types of contemporary DES. (Evaluation of the First, Second, and New Drug-Eluting Stents in Routine Clinical Practice [IRIS-DES]; NCT01186133).

Comparison of Long-Term Outcomes Following Coronary Revascularization in Men-vs-Women with Unprotected Left Main Disease

Gender differences have been recognized in several aspects of coronary artery disease (CAD). However, evidence for gender differences in long-term outcomes after left main coronary artery (LMCA) revascularization is limited. We sought to evaluate the impact of gender on outcomes after percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) for unprotected LMCA disease. We evaluated 4,320 patients with LMCA disease who underwent CABG (n = 1,456) or PCI (n = 2,864) from the Interventional Research Incorporation Society-Left MAIN Revascularization registry. The primary outcome was a composite of death, myocardial infarction (MI), or stroke. Among 4,320 patients, 968 (22.4%) were females and 3,352 (77.6%) were males. Compared to males, females were older, had a higher prevalence of hypertension and insulin-requiring diabetes, more frequently presented with acute coronary syndrome, but had less extensive CAD and less frequent left main bifurcation involvement. The adjusted risk for the primary outcome was not different after PCI or CABG in females and males (hazard ratio [HR] 1.09; 95% confidence interval [CI]: 0.73-1.63 and HR 0.97; 95% CI: 0.80-1.19, respectively); there was no significant interaction between gender and the revascularization strategy (P for interaction = 0.775). In multivariable analysis, gender did not appear to be an independent predictor for the primary outcome. In revascularization for LMCA disease, females and males had a comparable primary composite outcome of death, MI, or stroke with either CABG or PCI without a significant interaction of gender with the revascularization strategy.

Long-Term Outcomes After PCI or CABG for Left Main Coronary Artery Disease According to Lesion Location

OBJECTIVES

The aim of this study was to investigate the impact of lesion site (ostial or shaft vs. distal bifurcation) on long-term outcomes after percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) for left main coronary artery (LMCA) disease.

BACKGROUND

Long-term comparative data after PCI and CABG for LMCA disease according to lesion site are limited.

METHODS

Patients from the MAIN-COMPARE (Revascularization for Unprotected Left Main Coronary Artery Stenosis: Comparison of Percutaneous Coronary Angioplasty Versus Surgical Revascularization) registry were analyzed, comparing adverse outcomes (all-cause mortality [a composite outcome of death, Q-wave myocardial infarction, or stroke] and target vessel revascularization) between PCI and CABG according to LMCA lesion location during a median follow-up period of 12.0 years.

RESULTS

In overall population, the adjusted risks for death and serious composite outcome were higher after PCI than after CABG for distal bifurcation disease, which was mainly separated beyond 5 years. These outcomes were not different for ostial or shaft disease. When comparing drug-eluting stents (DES) and CABG, the adjusted risks for death and serious composite outcome progressively diverged beyond 5 years after DES compared with CABG for distal bifurcation disease (death: hazard ratio: 1.78; 95% confidence interval: 1.22 to 2.59; composite outcome: hazard ratio: 1.94; 95% confidence interval: 1.35 to 2.79). This difference was driven mainly by PCI with a 2-stent technique for distal bifurcation. In contrast, the adjusted risks for these outcomes were similar between DES and CABG for ostial or shaft disease.

CONCLUSIONS

Among patients with distal LMCA bifurcation disease, CABG showed lower mortality and serious composite outcome rates compared with DES beyond 5 years. However, there were no between-group differences in these outcomes among patients with ostial or shaft LMCA disease.

Association of Stage 1 Hypertension Defined by the ACC/AHA 2017 Guideline With Asymptomatic Coronary Atherosclerosis

BACKGROUND

This study sought to assess the relationship between stage 1 hypertension and subclinical coronary atherosclerosis.

METHODS

A total of 4,666 individuals with available coronary computed tomography angiography (CCTA) results from a health checkup were enrolled. The classification of hypertension was adapted from the American College of Cardiology/American Heart Association (ACC/AHA) 2017 guideline. The presence of coronary plaques and its characteristics, and other CCTA findings were assessed.

RESULTS

There was a linear relationship between blood pressure (BP), both systolic BP (SBP) and diastolic BP (DBP), and the presence of coronary plaque. Patients were classified into 4 groups according to the BP category: normal BP (SBP <120 mm Hg and DBP <80 mm Hg; n = 2,395; 51.3%), elevated BP (SBP 120-129 mm Hg and DBP <80 mm Hg; n = 467; 10.0%), stage 1 hypertension (SBP 130-139 mm Hg or DBP 80-89 mm Hg; n = 1,139; 24.4%), and stage 2 hypertension (SBP ≥140 mm Hg or DBP ≥90 mm Hg; n = 665; 14.2%). Compared with the normal BP group after multivariate adjustment, the stage 1 hypertension group was significantly associated with the presence of atherosclerotic plaque (adjusted odds ratio [95% confidential interval], 1.37 [1.17-1.62]; P < 0.001), especially in noncalcified and mixed plaques. The relationship between stage 1 hypertension and stenosis >50% was not statistically significant. Isolated diastolic and isolated systolic stage 1 hypertensions were significantly related to the presence of coronary plaque. The elevated BP group was not associated with any positive CCTA findings.

CONCLUSIONS

Stage 1 hypertension was independently associated with subclinical coronary atherosclerosis.

Intracranial Bleeding After Percutaneous Coronary Intervention: Time-Dependent Incidence, Predictors, and Impact on Mortality

Background

Limited data are available on intracranial hemorrhage (ICH) in patients undergoing antithrombotic therapy after percutaneous coronary intervention (PCI).

Methods and Results

Using the Korean National Health Insurance Service database, we identified 219 274 patients without prior ICH and who underwent a first PCI procedure between 2007 and 2016 and analyzed nontraumatic ICH and all‐cause mortality. ICH after PCI occurred in 4171 patients during a median follow‐up of 5.6 years (overall incidence rate: 3.32 cases per 1000 person‐years). The incidence rate of ICH showed an early peak of 21.66 cases per 1000 person‐years within the first 30 days, followed by a sharp decrease to 3.68 cases per 1000 person‐years between 30 days and 1 year, and to <1 case per 1000 patient‐years from the second year until 10 years after PCI. The 1‐year mortality rate was 38.2% after ICH, with most deaths occurring within 30 days (n=999, mortality rate: 24.2%). No significant difference in mortality risk was observed between patients who had ICH within and after 1 year following PCI (adjusted hazard ratio, 1.04; 95% CI, 0.95–1.14; P=0.43). The predictors of post‐PCI ICH were age ≥75 years, hypertension, atrial fibrillation, end‐stage renal disease, history of stroke or transient ischemic attack, dementia, and use of vitamin K antagonists.

Conclusions

New ICH most frequently occurs in the early period after PCI and is associated with a high risk of early death, regardless of the occurrence time of ICH. Careful implementation of antithrombotic strategies is needed in patients at an increased risk for ICH, particularly in the peri‐PCI period.

Ten-year Outcomes After Drug-Eluting Stents or Bypass Surgery for Left Main Coronary Disease in Patients With and Without Diabetes Mellitus: The PRECOMBAT Extended Follow-Up Study

Background

Several trials reported differential outcomes after percutaneous coronary intervention with drug‐eluting stents (DES) and coronary‐artery bypass grafting (CABG) for multivessel coronary disease according to the presence of diabetes mellitus (DM). However, it is not well recognized how DM status affects very‐long‐term (10‐year) outcomes after DES and CABG for left main coronary artery disease.

Methods and Results

In the PRECOMBAT (Premier of Randomized Comparison of Bypass Surgery versus Angioplasty using Sirolimus‐Eluting Stent in Patients with Left Main Coronary Artery Disease) trial, patients with LMCA were randomly assigned to undergo PCI with sirolimus‐eluting stents (n=300) or CABG (n=300). The primary outcome was the incidence of major adverse cardiac or cerebrovascular events (MACCE; a composite of death from any cause, myocardial infarction, stroke, or ischemia‐driven target‐vessel revascularization). Outcomes were examined in patients with (n=192) and without (n=408) medically treated diabetes. The follow‐up was extended to at least 10 years for all patients (median, 11.3 years). The 10‐year rates of MACCE were not significantly different between DES and CABG in patients with DM (36.3% versus 26.7%, respectively; hazard ratio [HR], 1.35; 95% CI, 0.83–2.19; P=0.23) and without DM (25.3% versus 22.9%, respectively; HR, 1.15; 95% CI, 0.79–1.67; P=0.48) (P‐for‐interaction=0.48). There were no significant between‐group differences in composite of death, MI, or stroke, and all‐cause mortality, regardless of DM status. TVR rates were consistently higher after DES than CABG.

Conclusions

In this 10‐year extended follow‐up of PRECOMBAT, we found no significant difference between DES and CABG with respect to the incidences of MACCE, serious composite outcome, and all‐cause mortality in patients with and without DM with LMCA disease. However, owing to the limited number of patients and no adjustment for multiple testing, overall findings should be considered hypothesis‐generating, highlighting the need for further research.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03871127 and NCT00422968.

Prognostic Effect of the SYNTAX Score on 10-Year Outcomes After Left Main Coronary Artery Revascularization in a Randomized Population: Insights From the Extended PRECOMBAT Trial

Background

The long‐term prognostic effect of the SYNTAX (Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) score (SS) after percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) for left main coronary artery disease is controversial.

Methods and Results

In the PRECOMBAT (Premier of Randomized Comparison of Bypass Surgery Versus Angioplasty Using Sirolimus‐Eluting Stent in Patients With Left Main Coronary Artery Disease) trial, 600 patients with left main coronary artery disease were randomized to undergo PCI with drug‐eluting stents (n=300) or CABG (n=300). We compared 10‐year outcomes after PCI and CABG according to SS categories and evaluated the predictive value of SS in each revascularization arm. The primary outcome was a major adverse cardiac or cerebrovascular event (composite of death, myocardial infarction, stroke, or ischemia‐driven target‐vessel revascularization) at 10 years. Among 566 patients with valid SS measurement at baseline, 240 (42.4%) had low SS, 200 (35.3%) had intermediate SS, and 126 (22.3%) had high SS. The 10‐year rates of major adverse cardiac or cerebrovascular events were not significantly different between PCI and CABG in low (21.6% versus 22.2%, P=0.97), intermediate (31.8% versus 22.2%; P=0.13), and high SS (46.2% versus 35.7%; P=0.31) (P‐for‐interaction=0.46). There were no significant interactions between SS categories and revascularization modalities for death (P=0.92); composite of death, myocardial infarction, or stroke (P=0.87); and target‐vessel revascularization (P=0.06). Higher SS categories were associated with higher risks for major adverse cardiac or cerebrovascular events in the PCI arm but not in the CABG arm.

Conclusions

Ten‐year clinical outcomes between PCI and CABG were not significantly different according to the SS. The SS was predictive of major adverse cardiac or cerebrovascular events after PCI but not after CABG.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03871127.