The Current Status of Percutaneous Coronary Intervention in Korea: Based on Year 2014 & 2016 Cohort of Korean Percutaneous Coronary Intervention (K-PCI) Registry

Intravascular Imaging-Guided Versus Angiography-Guided Complex PCI in Patients With High Bleeding Risk: A Secondary Analysis of the RENOVATE-COMPLEX PCI Trial

BACKGROUND

Although patients with high bleeding risk (HBR) often have complex coronary artery lesions, it is not known whether intravascular imaging-guided percutaneous coronary intervention (PCI) improves their prognosis. We sought to investigate the benefit of intravascular imaging-guided PCI for complex coronary artery lesions in patients with HBR.

METHODS

This was a secondary analysis of the RENOVATE-COMPLEX-PCI trial (Randomized Controlled Trial of Intravascular Imaging Guidance Versus Angiography-Guidance on Clinical Outcomes After Complex Percutaneous Coronary Intervention) in which patients with complex coronary artery lesions undergoing PCI were enrolled at 20 sites in Korea from May 2018 through May 2021. Patients were randomized to receive intravascular imaging-guided PCI or angiography-guided PCI and classified according to the presence of HBR. The primary end point was target vessel failure, which was a composite of cardiac death, target vessel-related myocardial infarction, or clinically driven target vessel revascularization.

RESULTS

Of 1639 trial population, 478 patients met HBR criteria. There was no significant difference in the risk of the primary end point between HBR and non-HBR patients (11.8% versus 8.2%; adjusted hazard ratio [HR], 1.05 [95% CI, 0.72-1.54]; P=0.790). However, patients with HBR were at higher risk for cardiac death or spontaneous target vessel-related myocardial infarction (adjusted HR, 2.04 [95% CI, 1.09-3.80]; P=0.025), all-cause death (adjusted HR, 3.30 [95% CI, 1.93-5.62]; P<0.001), and cardiac death (adjusted HR, 2.36 [95% CI, 1.10-5.09]; P=0.028). Intravascular imaging-guided PCI showed a lower risk of the primary end point compared with angiography-guided PCI in both HBR patients (9.7% versus 15.8%; adjusted HR, 0.57 [95% CI, 0.31-1.02]; P=0.060) and non-HBR patients (6.9% versus 10.8%; adjusted HR, 0.65 [95% CI, 0.43-0.99]; P=0.045), without significant interaction (P for interaction=0.796).

CONCLUSIONS

Patients with HBR were associated with an increased risk of adverse cardiovascular events after complex PCI compared with those without HBR. Intravascular imaging-guided PCI showed a lower risk of the target vessel failure without significant interaction between treatment strategy and the presence of HBR in patients undergoing complex PCI.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03381872.

Contemporary Use of Post-Dilatation for Stent Optimization During Percutaneous Coronary Intervention; Results From the Netherlands Heart Registration

BACKGROUNDS

Post-dilatation after stenting with a non-compliant (NC) balloon can be used to improve overall percutaneous coronary intervention (PCI) result. Due to lack of evidence on the effect of post-dilatation on adverse clinical endpoints there is no consensus whether post-dilatation should be used routinely. The aim of the current study was to determine the contemporary practice of post-dilatation.

METHODS

This study included patients from the Netherlands Heart Registration who underwent PCI between the 4th quarter of 2020 and the 3rd quarter of 2021. The primary endpoint was the rate of post-dilatation with a NC balloon. Secondary endpoints included differences in baseline and procedural characteristics of patients that received post-dilatation and patients that did not receive post-dilatation.

RESULTS

Out of 12,960 patients from 11 hospitals, 49.9% underwent post-dilatation. There was a variety in post-dilatation between hospitals ranging from 29.3% to 82.7% and among operators ranging from 15.9% to 90.5%. Post-dilatation was used less frequent in patients presenting with ST-elevation myocardial infarction or out of hospital cardiac arrest. Multivessel and left main PCI, long stent length and use of intracoronary imaging and calcium modification were associated with increased use of post-dilatation. When imaging was used, the percentage of post-dilatation was 79.4%.

CONCLUSIONS

In the Netherlands, stent optimization with post-dilatation using NC balloon is performed in only half of the patients undergoing PCI, with variations in frequency across centres and operators. Post-dilatation is more often used in cases of complex PCI and when intracoronary imaging or calcium modification techniques are used.

Outcomes of Deferring Percutaneous Coronary Intervention Without Physiologic Assessment for Intermediate Coronary Lesions

BACKGROUND AND OBJECTIVES

Outcomes of deferring percutaneous coronary intervention (PCI) without invasive physiologic assessment for intermediate coronary lesions is uncertain. We sought to compare long-term outcomes between medical treatment and PCI of intermediate lesions without invasive physiologic assessment.

METHODS

A total of 899 patients with intermediate coronary lesions between 50% and 70% diameter-stenosis were randomized to the conservative group (n=449) or the aggressive group (n=450). For intermediate lesions, PCI was performed in the aggressive group, but was deferred in the conservative group. The primary endpoint was major adverse cardiac events (MACE, a composite of all-cause death, myocardial infarction [MI], or ischemia-driven any revascularization) at 3 years.

RESULTS

The number of treated lesions per patient was 0.8±0.9 in the conservative group and 1.7±0.9 in the aggressive group (p=0.001). At 3 years, the conservative group had a significantly higher incidence of MACE than the aggressive group (13.8% vs. 9.3%; hazard ratio [HR], 1.49; 95% confidence interval [CI], 1.00-2.21; p=0.049), mainly driven by revascularization of target intermediate lesion (6.5% vs. 1.1%; HR, 5.69; 95% CI, 2.20-14.73; p<0.001). Between 1 and 3 years after the index procedure, compared to the aggressive group, the conservative group had significantly higher incidence of cardiac death or MI (3.2% vs. 0.7%; HR, 4.34; 95% CI, 1.24-15.22; p=0.022) and ischemia-driven any revascularization.

CONCLUSIONS

For intermediate lesions, medical therapy alone, guided only by angiography, was associated with a higher risk of MACE at 3 years compared with performing PCI, mainly due to increased revascularization.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00743899.

Intravascular Imaging Predictors Associated With Cardiovascular Events After Complex PCIs

BACKGROUND

Intravascular imaging-guided percutaneous coronary intervention (PCI) has been shown to improve clinical outcomes in patients with complex coronary artery lesions compared with angiography-guided PCI. However, the prognostic impact of suboptimal findings on intravascular imaging such as stent underexpansion, malapposition, or dissection is unclear in the era of contemporary drug-eluting stents.

METHODS

From RENOVATE-COMPLEX-PCI (Randomized Controlled Trial of Intravascular Imaging Guidance Versus Angiography-Guidance on Clinical Outcomes After Complex Percutaneous Coronary Intervention) which compared imaging-guided PCI with angiography-guided PCI in patients with complex lesions, post-PCI intravascular imaging findings, including minimum stent area (MSA), relative stent underexpansion (MSA≤80% of the average reference lumen area), malapposition, or dissection, were assessed in nonleft main target lesions. The primary end point was target lesion failure (TLF), a composite of cardiac death, target lesion-related myocardial infarction, target lesion revascularization, or definite stent thrombosis.

RESULTS

A total of 897 nonleft main lesions from 714 patients undergoing imaging-guided PCI were included. During a median follow-up duration of 2.1 years, the optimal cutoff value of MSA to predict the occurrence of TLF was 5.5 mm2, and MSA<5.5 mm2 was associated with a significantly higher risk of TLF than MSA≥5.5 mm2 (2.2% versus 4.8%; adjusted hazard ratio, 3.09 [95% CI, 1.01-9.50]; P=0.048). Compared with the reference group (MSA≥5.5 mm2 and no suboptimal findings), the subgroup of patients with MSA≥5.5 mm2 and post-PCI intravascular imaging findings of relative stent underexpansion, major malapposition, or major dissection was associated with a numerically increased risk of TLF (0.0% versus 3.2%; P=0.057). Compared with the same reference group, the subgroup of patients with MSA<5.5 mm2 and suboptimal post-PCI intravascular imaging findings was associated with a significantly increased risk of TLF (0.0% versus 4.7%; P=0.017).

CONCLUSIONS

After intravascular imaging-guided PCI with contemporary drug-eluting stents for nonleft main complex lesions, inadequate absolute stent expansion was independently associated with a higher risk of TLF. Suboptimal post-PCI intravascular imaging findings of relative stent underexpansion, major malapposition, and major dissection seem to contribute to the risk of TLF.

REGISTRATION

https://www.clinicaltrials.gov; Unique identifier: NCT03381872.

Retrospective Analysis of the Thai Percutaneous Coronary Intervention Registry: Impacts of Center Volume and Operator Experience on Outcomes

BACKGROUND

Percutaneous coronary intervention (PCI) outcomes can vary due to various factors, including patient clinical condition, complexity of coronary lesions, expertise of operators, and quality of the PCI center.

AIMS

This study evaluated the influence of PCI center volume and operator experience on patient outcomes after the procedure.

METHODS

Retrospective data on demographic, clinical details, and outcomes for all patients undergoing PCI across 39 hospitals in Thailand from 2018 to 2019 were retrieved. PCI center volume was categorized based on annual number of interventions: low (< 200), intermediate (200-499), and high (≥ 500). Operator experience was assessed by years of practice (low [< 5] and high [≥ 5]) and the number of PCI cases performed annually (low [< 75] and high [≥ 75]). The evaluated PCI outcomes were: PCI failure; procedural complications; PCI-related in-hospital mortality; 1 year post-intervention all-cause mortality.

RESULTS

A total of 19,701 patients who underwent PCI were included in the analysis, of whom 17,432 had follow-up data available after 1 year. Of these, 58.1% presented with either ST-elevation or non-ST elevation myocardial infarction/unstable angina, while 41.9% had stable CAD. Nearly half of the patients had triple-vessel or left-main disease, and 8.7% presented with cardiogenic shock. The percent with PCI failure, procedural complications, PCI-related in-hospital death, and 1-year all-cause mortality were 4.9%, 5.1%, 2.7%, and 11.8%, respectively. Despite patients in higher-risk profiles being treated at high-volume PCI centers and by experienced operators, there were no significant differences in PCI failure, PCI-related in-hospital mortality nor 1-year all-cause mortality compared to those treated at low or intermediate volume PCI centers. However, high-volume PCI centers had procedural complications more frequently (4.7%) than did intermediate (3.9%) and low-volume (2.5%) centers (p < 0.001). After adjusting for confounding factors, no significant associations were found between PCI center volume and PCI outcome. Similarly, no significant relationship was found between operator experience and procedural complications, nor 1-year all-cause mortality. Nevertheless, operators with more years of practice were associated with lower PCI-related in-hospital mortality (odds ratio [95% CI] of 0.75 (0.57, 0.98); p < 0.038). Additionally, operators conducting a higher number of PCIs annually tended to have less PCI failures (odds ratio [95% CI] of 0.76 (0.57, 1.01); p = 0.062).

CONCLUSION

A center's PCI volume did not significantly impact PCI outcome. In contrast, operator experience did impact outcomes. This result highlights areas for improvement and can help reform strategies for national PCI systems at both center and operator levels.

Intravascular Imaging-Guided Percutaneous Coronary Intervention in Patients With End-Stage Renal Disease on Maintenance Dialysis

Background

Patients with end-stage renal disease (ESRD) are at a higher risk of cardiovascular diseases. Intravascular imaging (IVI)-guided percutaneous coronary intervention (PCI) using optical coherence tomography (OCT) or intravascular ultrasound (IVUS) has been shown to result in better clinical outcomes than angiography guidance. Nevertheless, the clinical outcomes of IVI-guided PCI in ESRD patients remain uncertain.

Objectives

This study aimed to compare the clinical outcomes of OCT- and IVUS-guided PCIs in ESRD patients and to report the trend of IVI-guided PCI in Taiwan.

Methods

Patients with ESRD on maintenance dialysis, who underwent OCT- or IVUS-guided PCI from 2015 to 2021, were compared by propensity-score matching. The primary outcome was composite cardiovascular outcomes, including coronary revascularization, cardiovascular death, and acute myocardial infarction.

Results

In 2021, IVI was used to guide PCIs in 27% (15,613 of 57,845) of general and 27.5% (1,754 of 6,387) of ESRD patients. Among 4,759 eligible ESRD patients, 443 and 4,316 patients underwent OCT- and IVUS-guided PCIs, respectively. After matching, the incidence of the primary outcome was comparable between the OCT and IVUS groups (42.1 [95% CI: 36.2-48.0] vs 47.6 [95% CI: 43.0-52.2] events per 100 person-years; HR: 0.88; 95% CI: 0.74-1.06). The results were similar for all components of the primary outcome and in subgroup analyses.

Conclusions

The number of PCI- and IVI-guided procedures has progressively increased in the past decade in Taiwan in both the general and ESRD populations. Among ESRD patients on maintenance dialysis, the clinical outcomes were comparable between OCT- and IVUS-guided PCI.

Intravascular imaging-guided percutaneous coronary intervention in patients with acute myocardial infarction and cardiogenic shock

INTRODUCTION AND OBJECTIVES

There are no clinical data on the efficacy of intravascular imaging-guided percutaneous coronary intervention (PCI) compared with angiography-guided PCI in patients with acute myocardial infarction (AMI) and cardiogenic shock. The current study sought to evaluate the impact of intravascular imaging-guided PCI in patients with AMI and cardiogenic shock.

METHODS

Among a total of 28 732 patients from the nationwide pooled registry of KAMIR-NIH (November, 2011 to December, 2015) and KAMIR-V (January, 2016 to June, 2020), we selected a total of 1833 patients (6.4%) with AMI and cardiogenic shock who underwent PCI of the culprit vessel. The primary endpoint was major adverse cardiovascular events (MACE) at 1 year, a composite of cardiac death, myocardial infarction, repeat revascularization, and definite or probable stent thrombosis.

RESULTS

Among the study population, 375 patients (20.5%) underwent intravascular imaging-guided PCI and 1458 patients (79.5%) underwent angiography-guided PCI. Intravascular imaging-guided PCI was associated with a significantly lower risk of 1-year MACE than angiography-guided PCI (19.5% vs 28.2%; HR, 0.59; 95%CI, 0.45-0.77; P<.001), mainly driven by a lower risk of cardiac death (13.7% vs 24.0%; adjusted HR, 0.53; 95%CI, 0.39-0.72; P<.001). These results were consistent in propensity score matching (HR, 0.68; 95%CI, 0.46-0.99), inverse probability weighting (HR, 0.61; 95%CI, 0.45-0.83), and Bayesian analysis (Odds ratio, 0.66, 95% credible interval, 0.49-0.88).

CONCLUSIONS

In AMI patients with cardiogenic shock, intravascular imaging-guided PCI was associated with a lower risk of MACE at 1-year than angiography-guided PCI, mainly driven by the lower risk of cardiac death.

The Western Denmark Heart Registry and Population-Based National Health Registries

The Western Denmark Heart Registry (WDHR) is a semi-national, multicenter-based clinical registry with unique potential for cardiovascular research. The registry has provided detailed prospectively registered information on patient and procedure characteristics since 1999. WDHR data can be linked to additional data in other healthcare registries in Denmark. Therefore, the WDHR is a valuable data resource for cardiovascular research, providing a foundation for numerous research projects and publications. This review describes three currently available cohorts from the WDHR containing individual-level information on: i) 200,647 first-time coronary angiographies from 2003 to 2021, ii) 88,630 first-time percutaneous coronary interventions from 1999 to 2022, and iii) 85,512 first-time coronary computed tomography angiographies from 2008 to 2021. Furthermore, we describe other frequently cross-linked Danish healthcare registries containing information on various patient characteristics and outcomes, such as vital status, cause of death, hospitalizations, medications, and laboratory test results. The comprehensive overview of these cohorts aims to assist researchers, collaborators, and other interested parties in understanding the scope and potential applications of the available data. All cohorts are regularly updated, thereby supporting continuing research on cardiovascular clinical practice and prognosis in Denmark.

Cost-Effectiveness of Intravascular Imaging-Guided Complex PCI: Prespecified Analysis of RENOVATE-COMPLEX-PCI Trial

BACKGROUND

Although clinical benefits of intravascular imaging-guided percutaneous coronary intervention (PCI) in patients with complex coronary artery lesions have been observed in previous trials, the cost-effectiveness of this strategy is uncertain.

METHODS

RENOVATE-COMPLEX-PCI (Randomized Controlled Trial of Intravascular Imaging Guidance vs Angiography-Guidance on Clinical Outcomes After Complex Percutaneous Coronary Intervention) was conducted in Korea between May 2018 and May 2021. This prespecified cost-effectiveness substudy was conducted using Markov model that simulated 3 states: (1) post-PCI, (2) spontaneous myocardial infarction, and (3) death. A simulated cohort was derived from the intention-to-treat population, and input parameters were extracted from either the trial data or previous publications. Cost-effectiveness was evaluated using time horizon of 3 years (within trial) and lifetime. The primary outcome was incremental cost-effectiveness ratio (ICER), an indicator of incremental cost on additional quality-adjusted life years (QALYs) gained, in intravascular imaging-guided PCI compared with angiography-guided PCI. The current analysis was performed using the Korean health care sector perspective with reporting the results in US dollar (1200 Korean Won, ₩=1 dollar, $). Willingness to pay threshold was $35 000 per QALY gained.

RESULTS

A total of 1639 patients were included in the trial. During 3-year follow-up, medical costs ($8661 versus $7236; incremental cost, $1426) and QALY (2.34 versus 2.31; incremental QALY, 0.025) were both higher in intravascular imaging-guided PCI than angiography-guided PCI, resulting incremental cost-effectiveness ratio of $57 040 per QALY gained within trial data. Conversely, lifetime simulation showed total cumulative medical cost was reversed between the 2 groups ($40 455 versus $49 519; incremental cost, -$9063) with consistently higher QALY (8.24 versus 7.89; incremental QALY, 0.910) in intravascular imaging-guided PCI than angiography-guided PCI, resulting in a dominant incremental cost-effectiveness ratio. Consistently, 70% of probabilistic iterations showed cost-effectiveness of intravascular imaging-guided PCI in probabilistic sensitivity analysis.

CONCLUSIONS

The current cost-effectiveness analysis suggests that imaging-guided PCI is more cost-effective than angiography-guided PCI by reducing medical cost and increasing quality-of-life in complex coronary artery lesions in long-term follow-up.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03381872.

Estimation of Supply and Demand for Cardiologists in Korea

BACKGROUND AND OBJECTIVES

The objective of this study was to estimate the supply and demand for cardiologists in Korea and provide evidence for healthcare policy to ensure a stable and adequate workforce for optimal cardiovascular disease management.

METHODS

Past trends of inflow and outflow of cardiologists were used to make crude projections, which were then adjusted based on demands of services to obtain final projections. Inflow of cardiologists was estimated using second-order polynomial regression and demand for cardiology care was estimated using linear regression.

RESULTS

There were 1,139 active cardiologists who were under the age of 65 in clinical practice in Korea. The estimated number of cardiologists from 2022 to 2040 showed that the number of cardiologists would peak at 1,344 in 2032 and gradually decrease thereafter. We also estimated an increase of 947,811 cases of heart-related procedures annually from 2023 to 2032. The number of heart-related procedures per cardiologist would increase 1.4 times from 12,964 in 2023 to 17,862 in 2032. The estimated number of emergency patients per cardiologist under 50 years old would almost double from 544 in 2022 to 987 in 2032.

CONCLUSIONS

We expect significant shortage of cardiologists in Korea within the next 10 years. The number of emergency patients per cardiologist will increase by nearly 50%, leading to high individual workload for cardiologists. To prevent this imbalance between supply and demand, an organized and collective approach by the specialty of cardiology is imperative to produce a balanced workforce.

Validation of artificial intelligence-based quantitative coronary angiography

Background

Coronary angiography is fundamental for the diagnosis and treatment of coronary artery disease. Manual quantitative coronary angiography (QCA) is accurate and reproducible; however, it is time-consuming and labor-intensive. However, recent advancements in artificial intelligence (AI) have enabled automated and rapid analysis of medical images, addressing the need for real-time quantitative coronary analysis.

Aims

This study aimed to evaluate the accuracy of AI-based QCA (AI-QCA) compared with that via manual QCA and clinician acceptance.

Methods

This retrospective, single-center study was conducted in two phases. Phase 1 was a pilot study comparing AI-QCA with manual QCA and visual estimation. It involved 15 patients who underwent coronary angiography at Seoul National University Bundang Hospital between September 2011 and July 2021. Phase 2 included a larger cohort of 762 patients, with 1002 coronary angiograms analyzed between May 2020 and April 2021.

Results

In phase 1, AI-QCA and manual QCA consistency varied among the observers, with AI-QCA showing superior consistency compared with visual estimation. However, a strong correlation between AI-QCA and manual-QCA was found in phase 2. AI-QCA accurately identified and quantitatively analyzed multiple lesions in the major vessels, providing results comparable with those of manual QCA.

Conclusions

AI-QCA demonstrated high concordance with manual QCA, offering real-time analysis and reduced workload. Therefore, AI-QCA has the potential to be a valuable tool for diagnosing and treating coronary artery disease, necessitating further studies for clinical validation.

Effect of risk factor-tailored autonomy enhancement education in the first-time middle-aged patients undergoing percutaneous coronary intervention: a randomized controlled trial

PURPOSE

It is important for middle-aged patients who have undergone acute treatment for coronary artery disease to voluntarily improve their lifestyle and risk factors based on their recognition as patients with chronic diseases. This study conducted individual education to improve risk factors and tried to verify its effectiveness.

METHODS

The hypothesis was verified by applying a randomized controlled pre- and post-test design through random assignment of two groups. Middle-aged (40-64 years) patients who underwent percutaneous coronary intervention for the first time were recruited from a university hospital in Seoul, Korea. For the experimental group, based on the Self-Determination Theory, risk factor- tailored counseling and education were provided individually for one hour based on the education booklet, and telephone counseling was conducted twice for 12 weeks. Differences in autonomous motivation, resilience, self-care compliance and biochemical indicators measured after 12 weeks in the experimental group and the control group were compared. Data were analyzed using SPSS/WIN ver. 22.0.

RESULTS

The autonomous motivation, resilience, and self-care compliance of the experimental group were significantly higher than those of the control group (p < .05). Body mass index (p = .005) and current smoking rate (p < .001) were also significantly decreased in the experimental group but there was no significant difference in other biochemical parameters.

CONCLUSION

For middle-aged patients with first coronary intervention, risk factor-tailored education emphasizing autonomy by nurses should be provided early after discharge.

TRIAL REGISTRATION

This study was retrospectively registered in the Clinical Research Information Service and the identification number is KCT0008698(11/08/2023).

Clinical Benefit of Intravascular Imaging Compared With Conventional Angiography in Left Main Coronary Artery Intervention

BACKGROUND

The RENOVATE-COMPLEX-PCI (Randomized Controlled Trial of Intravascular Imaging Guidance Versus Angiography-Guidance on Clinical Outcomes After Complex Percutaneous Coronary Intervention) demonstrated that intravascular imaging-guided percutaneous coronary intervention (PCI) improved clinical outcome compared with angiography-guided PCI for patients with complex coronary artery lesions. This study aims to assess whether the prognostic benefit of intravascular imaging-guided procedural optimization persists in patients undergoing PCI for left main coronary artery disease.

METHODS

Of 1639 patients enrolled in the RENOVATE-COMPLEX-PCI, 192 patients with left main coronary artery disease were selected for the current prespecified substudy. Selected patients were randomly assigned to either the intravascular imaging-guided PCI group (n=138) or the angiography-guided PCI group (n=54). The primary end point was target vessel failure defined as a composite of cardiac death, target vessel-related myocardial infarction, or clinically driven target vessel revascularization.

RESULTS

At a median follow-up of 2.1 years (interquartile range 1.1 to 3.0 years), intravascular imaging-guided PCI was associated with lower incidence of primary end point compared with angiography-guided PCI (6.8% versus 25.1%; hazard ratio, 0.31 [95% CI, 0.13-0.76]; P=0.010). This significant reduction in primary end point was mainly driven by a lower risk of cardiac death or spontaneous target vessel-related myocardial infarction (1.6% versus 12.7%; hazard ratio, 0.16 [95% CI, 0.03-0.82]; P=0.028). Intravascular imaging-guided PCI was independently associated with a lower risk of primary end point, even after adjusting for various clinical factors (hazard ratio, 0.29 [95% CI, 0.12-0.72]; P=0.007).

CONCLUSIONS

Intravascular imaging-guided PCI showed clinical benefit over angiography-guided PCI for left main coronary artery disease in reducing the risk of cardiac death, target vessel-related myocardial infarction, or target vessel revascularization.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03381872.

Accuracy of IVUS-Based Machine Learning Segmentation Assessment of Coronary Artery Dimensions and Balloon Sizing

Background

Accurate intravascular ultrasound (IVUS) measurements are important in IVUS-guided percutaneous coronary intervention optimization by choosing the appropriate device size and confirming stent expansion.

Objectives

The purpose of this study was to assess the accuracy of machine learning (ML) automatic segmentation of coronary artery vessel and lumen dimensions and balloon sizing.

Methods

Using expert analysis as the gold standard, ML segmentation of 60 MHz IVUS images was developed using 8,076 IVUS cross-sectional images from 234 patients, which were randomly split into training (83%) and validation (17%) data sets. The performance of ML segmentation was then evaluated using an independent test data set (437 images from 92 patients). The endpoints were the agreement rate between ML vs experts' measurements for appropriate balloon size selection, and lumen and acute stent areas. Appropriate balloon size was determined by rounding down from the mean vessel diameter or rounding up from the mean lumen diameter to the next balloon size. The difference of lumen area ≥0.5 mm2 was considered as clinically significant.

Results

ML model segmentation correlated well with experts' segmentation for training data set with a correlation coefficient of 0.992 and 0.993 for lumen and vessel areas, respectively. The agreement rate in lumen and acute stent areas was 85.5% and 97.0%, respectively. The agreement rate for appropriate balloon size selection was 70.6% by vessel diameter only and 92.4% by adding lumen diameter.

Conclusions

ML model IVUS segmentation measurements were well-correlated with those of experts and selected an appropriate balloon size in more than 90% of images.

Impact of the adjunctive use criteria for intravascular ultrasound-guided percutaneous coronary intervention and clinical outcomes

The impact of the adherence to the adjunctive use criteria (AUC) for intravascular ultrasound (IVUS) guided percutaneous coronary intervention (PCI) and clinical outcomes in low IVUS volume countries are limited. The current study compared the procedural success and complication rates between used and not used IVUS catheter in the patients who were met (C +) and were not met (C-) the AUC for IVUS-guided PCI. From June 2018 through June 2019, a total of 21,066 patients were included in the Thai PCI registry. Among the study population, 15,966 patients (75.8%) have met the IVUS-AUC. The IVUS-guided PCI rates were 14.5% and 11.3% in the C + and C - groups, respectively. After adjusting for covariables by propensity model, IVUS-guided PCI was identified as an independent predictor of the procedural success rate regardless of whether the AUC were met with the relative risk [RR (95% confidence interval (CI)] of 1.033(1.026-1.040) and 1.012(1.002-1.021) in C + and C- groups, respectively. IVUS-guided PCI increased the procedural complication risks in both groups but were not significant with corresponding RRs of 1.171(0.915-1.426) and 1.693(0.959-2.426). Procedural success was achieved with IVUS-guided PCI regardless of whether the AUC were met. IVUS-guided PCI did not lead to an increase in procedural complications.

Accuracy of Artificial Intelligence-Based Automated Quantitative Coronary Angiography Compared to Intravascular Ultrasound: Retrospective Cohort Study. (Preprint)

BACKGROUND

An accurate quantitative analysis of coronary artery stenotic lesions is essential to make optimal clinical decisions. Recent advances in computer vision and machine learning technology have enabled the automated analysis of coronary angiography.

OBJECTIVE

The aim of this paper is to validate the performance of artificial intelligence-based quantitative coronary angiography (AI-QCA) in comparison with that of intravascular ultrasound (IVUS).

METHODS

This retrospective study included patients who underwent IVUS-guided coronary intervention at a single tertiary center in Korea. Proximal and distal reference areas, minimal luminal area, percent plaque burden, and lesion length were measured by AI-QCA and human experts using IVUS. First, fully automated QCA analysis was compared with IVUS analysis. Next, we adjusted the proximal and distal margins of AI-QCA to avoid geographic mismatch. Scatter plots, Pearson correlation coefficients, and Bland-Altman were used to analyze the data.

RESULTS

A total of 54 significant lesions were analyzed in 47 patients. The proximal and distal reference areas, as well as the minimal luminal area, showed moderate to strong correlation between the 2 modalities (correlation coefficients of 0.57, 0.80, and 0.52, respectively; P<.001). The correlation was weaker for percent area stenosis and lesion length, although statistically significant (correlation coefficients of 0.29 and 0.33, respectively). AI-QCA tended to measure reference vessel areas smaller and lesion lengths shorter than IVUS did. Systemic proportional bias was not observed in Bland-Altman plots. The biggest cause of bias originated from the geographic mismatch of AI-QCA with IVUS. Discrepancies in the proximal or distal lesion margins were observed between the 2 modalities, which were more frequent at the distal margins. After the adjustment of proximal or distal margins, there was a stronger correlation of proximal and distal reference areas between AI-QCA and IVUS (correlation coefficients of 0.70 and 0.83, respectively).

CONCLUSIONS

AI-QCA showed a moderate to strong correlation compared with IVUS in analyzing coronary lesions with significant stenosis. The main discrepancy was in the perception of the distal margins by AI-QCA, and the correction of margins improved the correlation coefficients. We believe that this novel tool could provide confidence to treating physicians and help in making optimal clinical decisions.

Patient Characteristics, Procedural Details, and Outcomes of Contemporary Percutaneous Coronary Intervention in Real-World Practice: Insights from Nationwide Thai PCI Registry

Background

Percutaneous coronary intervention (PCI) practice and outcomes vary substantially in different parts of the world. The contemporary data of PCI in Asia are limited and only available from developed Asian countries.

Objectives

To explore the pattern of practice and results of PCI procedures in Thailand as well as a temporal change of PCI practice over time compared with the registry from other countries.

Methods

Thai PCI Registry is a prospective nationwide registry that was an initiative of the Cardiac Intervention Association of Thailand (CIAT). All cardiac catheterization laboratories in Thailand were invited to participate during 2018-2019, and consecutive PCI patients were enrolled and followed up for 1 year. Patient baseline characteristics, procedural details, equipment and medication use, outcomes, and complications were recorded.

Results

Among the 39 hospitals participated, there were 22,741 patients included in this registry. Their mean age (standard deviation) was 64.2 (11.7) years and about 70% were males. The most common presentation was acute coronary syndrome (57%) with a high proportion of ST-elevation myocardial infarction (28%). Nearly two-thirds of patients had multivessel disease and significant left main stenosis was reported in 11%. The transradial approach was used in 44.2%. The procedural success rate was very high (95.2%) despite the high complexity of the lesions (56.9% type C lesion). The incidence of procedural complications was 5.3% and in-hospital mortality was 2.8%.

Conclusion

Thai PCI Registry provides further insights into the current practice and outcomes of PCI in Southeast Asia. The success rate was very high, and the complications were very low despite the high complexity of the treated lesions.

Off-hour presentation and outcomes for percutaneous coronary intervention in acute myocardial infarction with Killip III-IV

BACKGROUND/AIMS

Acute myocardial infarction (AMI) is conventionally recognized as an urgent medical condition requiring timely and effective reperfusion therapy. However, the results of studies on the clinical outcomes in AMI according to hospital visit timings are inconclusive. To explore the difference in long-term outcomes between off- and on-hour percutaneous coronary interventions (PCI) in patients with AMI of Killip functional classification III-IV (Killip III-IV AMI).

METHODS

Data on the characteristics and clinical outcomes of 1,751 patients with Killip III-IV AMI between November 2011 and June 2015 from the Korea Acute Myocardial Infarction Registry-National Institutes of Health registry were analyzed. All participants were allocated into two groups: off-hour (weekdays from 6:00 PM to 8:00 AM, weekends, and legal holidays) and on-hour (weekdays from 8:00 AM to 6:00 PM) groups. The incidence of major adverse cardiac and cerebrovascular events, defined as a composite of all-cause mortality, nonfatal myocardial infarction, any revascularization, cerebrovascular accident, and stent thrombosis, was the primary endpoint.

RESULTS

Among the 1,751 patients, 572 (39.1%) underwent PCI during on-hours and 892 (60.9%) during off-hours. At the 3-year follow-up, no significant difference was found in the clinical outcomes between the two groups in both the unadjusted and propensity-score weighing-adjusted analyses.

CONCLUSION

The outcomes of patients with Killip III-IV AMI admitted during off- and on-hours were similar.

Long-term outcomes in ST-elevation myocardial infarction patients treated according to hospital visit time

BACKGROUND/AIMS

Rapid percutaneous coronary intervention (PCI) is the cornerstone of treatment for ST-elevation myocardial infarction (STEMI). However, there have been conflicting results regarding the differences in clinical outcomes between on-hours and off-hours presentation in STEMI patients. We aimed to examine the difference in long-term outcomes between off-hours and on-hours PCI in patients with STEMI.

METHODS

The characteristics and clinical outcomes of 5,364 STEMI patients between November 2011 and June 2015 from the Korea Acute Myocardial Infarction Registry-National Institutes of Health (KAMIR-NIH) registry were analyzed. Patients were divided into two groups: the off-hours group (weekdays from 6:01 PM to 7:59 AM, weekends, and legal holidays) and the on-hours group (weekdays from 8:00 AM to 6:00 PM). Major adverse cardiac and cerebrovascular events (MACCEs) were defined as a composite of allcause mortality, non-fatal myocardial infarction, any revascularization, cerebrovascular accident, and stent thrombosis. The primary endpoint was the occurrence of MACCEs, and all other clinical outcomes were analyzed.

RESULTS

A total of 3,119 patients (58.1%) underwent primary PCI due to STEMI during off-hours and 2,245 patients (41.9%) during on-hours. At 36 months, the clinical outcomes of the off-hours group were similar to those of the on-hours group in both the unadjusted and propensity score weighting-adjusted analyses.

CONCLUSION

Our analysis revealed that the long-term outcomes in STEMI patients admitted to hospitals during off-hours were similar to outcomes of those admitted during on-hours.

Clopidogrel monotherapy in patients with and without on-treatment high platelet reactivity: a SMART-CHOICE substudy

BACKGROUND

Although P2Y12 inhibitor monotherapy has emerged as a promising alternative for dual antiplatelet therapy (DAPT), there remains concern regarding the safety of clopidogrel monotherapy.

AIMS

We sought to investigate clinical outcomes of clopidogrel monotherapy in patients with and without on-treatment high platelet reactivity (HPR).

METHODS

In the SMART-CHOICE study, three-month DAPT followed by P2Y12 inhibitor monotherapy was compared with 12-month DAPT in patients undergoing percutaneous coronary intervention. A platelet function test was performed for 833 patients with clopidogrel-based therapy. The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE: a composite of all-cause death, myocardial infarction, or stroke) at 12 months.

RESULTS

Overall, 108 (13.0%) patients had HPR on clopidogrel. Patients with HPR had a significantly higher rate of MACCE than patients without HPR (8.7% vs 1.5%, adjusted HR 3.036, 95% CI: 1.060-8.693, p=0.038). The treatment effect of clopidogrel monotherapy for the 12-month MACCE was not significantly different compared with DAPT among patients with HPR (8.0% vs 9.4%, adjusted HR 0.718, 95% CI: 0.189-2.737, p=0.628) and without HPR (2.2% vs 0.9%, adjusted HR 2.587, 95% CI: 0.684-9.779, p=0.161; adjusted p for interaction=0.170).

CONCLUSIONS

Clopidogrel monotherapy showed treatment effects comparable to DAPT for MACCE in patients with or without HPR. However, HPR was significantly associated with an increased risk of MACCE in clopidogrel-treated patients regardless of maintenance of aspirin.

CLINICAL TRIAL REGISTRATION

Comparison Between P2Y12 Antagonist Monotherapy and Dual Antiplatelet Therapy After DES (SMART-CHOICE) (ClinicalTrials.gov: NCT02079194).

Barriers to the Implementation of Primary PCI in the Management of STEMI in Egypt

Introduction: Evidence-based guidelines recommend primary percutaneous coronary intervention (PPCI) be the mainstay reperfusion strategy for the treatment of ST-segment elevation myocardial infarction (STEMI) if it is performed in the proper time window. However, the Egyptian health care system is still struggling to provide such an important service. The aim of the present study, through a quantitative questionnaire, is to explore the current practice of STEMI management in Egypt, and to identify the barriers, opportunities, and potential areas for improvement.Methods and Results: The questionnaire was conducted in Egypt via face-to-face qualitative in-depth interviews with cardiologists from 14 PPCI-capable hospitals and 26 non-PPCI-capable hospitals. Participants were selected in view of their experience and knowledge. The study identified potential barriers to the implementation of PPCI among STEMI patients in Egypt. These barriers included the prehospital patient delay and emergency medical service delay, delay in the emergency department and delay in patient transfer to the CCU, unavailable equipment, catheterization laboratory activation delay, lack of trained interventional cardiologists, lack of regional STEMI networks and hospital policies, and insufficient ICU beds.Conclusion: Limited resources and health care system inadequacies have led to potential barriers that prevent suboptimal implementation of PPCI in Egypt. Efforts from all health care providers should be directed to overcome these identified barriers.

Contemporary Implications of ECG to Activation Time on Long-term Outcomes in Patients With ST-Segment Elevation Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention

PURPOSE

The prognosis of door to balloon time (DBT) after primary percutaneous coronary intervention (PPCI) in ST-segment elevation myocardial infarction (STEMI) has been extensively studied. However, the clinical implications of the ECG to activation time (EAT), as a component of DBT, on long-term outcomes are less well established. This study evaluates the association of EAT with major adverse cardiovascular events (MACEs) in more contemporary patients undergoing PPCI and investigates factors that influence EAT.

METHODS

A total of 1082 consecutive patients with STEMI who underwent PPCI from 2013 to 2019 were classified into 3 groups according to EAT: EAT ≤30 minutes, EAT of 30 to 60 minutes, and EAT >60 minutes. We analyzed the incidence of MACEs, including all-cause death, nonfatal recurrence of MI, or nonfatal stroke during a median follow-up of 37 months.

FINDINGS

The median EAT was 58 minutes (interquartile range, 44-80 minutes), which explained 90% of the variability in DBT and had the strongest correlation with DBT (r = 0.95, P < 0.001). Achieving an EAT of ≤30 minutes resulted in a 94.1% chance of achieving a DBT ≤90 minutes. The incidence of MACEs had a concurrent increase with increased EAT (10.2% for EAT ≤30 minutes, 14.3% for EAT of 30-60 minutes, and 17.3% for EAT >60 minutes; P = 0.027) that was driven by more mortality (4.2% for EAT ≤30 minutes, 6.9% for EAT of 30-60 minutes, and 9.8% for EAT >60 minutes; P = 0.020). An EAT >30 minutes was independently associated with risk-adjusted long-term MACEs (hazard ratio = 1.99; 95% CI, 1.07-3.69; P = 0.030). Critically ill status in emergency department (P = 0.001) and time required for consent of revascularization (P < 0.001) were significantly associated with delayed EAT.

IMPLICATIONS

Achieving an EAT ≤30 minutes was key to achieving the guideline-recommended target time of DBT in contemporary practice. As a strong driver of overall DBT, EAT >30 minutes was associated with worse clinical outcome in patients with STEMI undergoing PPCI. These data suggest that efforts to minimize EAT are needed to reduce long-term MACEs in contemporary population. (Clin Ther. 2021;XX:XXX-XXX) © 2021 Elsevier HS Journals, Inc.

P2Y12 inhibitor monotherapy after coronary stenting according to type of P2Y12 inhibitor

OBJECTIVE

To compare P2Y12 inhibitor monotherapy after 3-month dual antiplatelet therapy (DAPT) with 12-month DAPT according to the type of P2Y12 inhibitor in patients undergoing percutaneous coronary intervention (PCI).

METHODS

The Smart Angioplasty Research Team: Comparison Between P2Y12 Antagonist Monotherapy vs Dual Antiplatelet Therapy in Patients Undergoing Implantation of Coronary Drug-Eluting Stents (SMART-CHOICE) randomised trial compared 3-month DAPT followed by P2Y12 inhibitor monotherapy with 12-month DAPT. In this trial, 2993 patients undergoing successful PCI with drug-eluting stent were enrolled in Korea. As a prespecified analysis, P2Y12 inhibitor monotherapy after 3-month DAPT versus 12-month DAPT were compared among patients receiving clopidogrel and those receiving potent P2Y12 inhibitor (ticagrelor or prasugrel), respectively. The primary endpoint was a composite of all-cause death, myocardial infarction or stroke at 12 months after the index procedure.

RESULTS

Among 2993 patients (mean age 64 years), 58.2% presented with acute coronary syndrome. Clopidogrel was prescribed in 2312 patients (77.2%) and a potent P2Y12 inhibitor in 681 (22.8%). There were no significant differences in the primary endpoint between the P2Y12 inhibitor monotherapy group and the DAPT group among patients receiving clopidogrel (3.0% vs 3.0%; HR: 1.02; 95% CI 0.64 to 1.65; p=0.93) as well as among patients receiving potent P2Y12 inhibitors (2.4% vs 0.7%; HR: 3.37; 95% CI 0.77 to 14.78; p=0.11; interaction p=0.1). Among patients receiving clopidogrel, P2Y12 inhibitor monotherapy compared with DAPT showed consistent treatment effects across various subgroups for the primary endpoint. Among patients receiving potent P2Y12 inhibitors, the rate of bleeding (Bleeding Academic Research Consortium types 2- 5) was significantly lower in the P2Y12 inhibitor monotherapy group than in the DAPT group (1.5% vs 5.0%; HR: 0.33; 95% CI 0.12 to 0.87; p=0.03).

CONCLUSIONS

Compared with 12-month DAPT, clopidogrel monotherapy after 3-month DAPT showed comparable cardiovascular outcomes in patients undergoing PCI.

TRIAL REGISTRATION NUMBER

NCT02079194.

Long-term Outcomes of Clopidogrel Monotherapy versus Prolonged Dual Antiplatelet Therapy beyond 12 Months after Percutaneous Coronary Intervention in High-risk Patients

BACKGROUND

There are no data on comparison between clopidogrel monotherapy and prolonged dual antiplatelet therapy (DAPT) in patients at high-risk undergoing percutaneous coronary intervention (PCI).

METHODS

Of 2,082 consecutive patients undergoing PCI using second-generation drug-eluting stent (DES), we studied 637 patients at high-risk either angiographically or clinically who received clopidogrel longer than 24 months and were event-free at 12 months after index PCI. Patients were divided into 2 groups: the clopidogrel monotherapy group and the prolonged DAPT group. The primary outcome was a composite of all-cause death, non-fatal myocardial infarction (MI), definite or probable stent thrombosis, or stroke between 12 months and 36 months after the index PCI.

RESULTS

In propensity score-matched population (246 pairs), the cumulative rate of primary outcome was 4.5% in the clopidogrel monotherapy group and 4.9% in the prolonged DAPT group (hazard ratio, 1.21; 95% confidence interval, 0.54-2.75; P = 0.643). There was no significant difference in all-cause death, MI, stent thrombosis, stroke between the clopidogrel monotherapy group and the prolonged DAPT group.

CONCLUSION

Compared with prolonged DAPT, clopidogrel monotherapy showed similar long-term outcomes in patients at high-risk after second-generation DES implantation.

The IMPact on Revascularization Outcomes of intraVascular ultrasound-guided treatment of complex lesions and Economic impact (IMPROVE) trial: Study design and rationale

Intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) has been shown in clinical trials, registries, and meta-analyses to reduce recurrent major adverse cardiovascular events after PCI. However, IVUS utilization remains low. An increasing number of high-risk or complex coronary artery lesions are treated with PCI, and we hypothesize that the impact of IVUS in guiding treatment of these complex lesions will be of increased importance in reducing major adverse cardiovascular events while remaining cost-effective. The "IMPact on Revascularization Outcomes of intraVascular ultrasound-guided treatment of complex lesions and Economic impact" trial (registered on clinicaltrials.gov: NCT04221815) is a multicenter, international, clinical trial randomizing subjects to IVUS-guided versus angiography-guided PCI in a 1:1 ratio. Patients undergoing PCI involving a complex lesion are eligible for enrollment. Complex lesion is defined as involving at least 1 of the following characteristics: chronic total occlusion, in-stent restenosis, severe coronary artery calcification, long lesion (≥28 mm), or bifurcation lesion. The clinical investigation will be conducted at approximately 120 centers in North America and Europe, enrolling approximately 2,500 to 3,100 randomized subjects with an adaptive design. The primary clinical end point is the rate of target vessel failure at 12 months, defined as the composite of cardiac death, target vessel-related myocardial infarction, and ischemia-driven target vessel revascularization. The co-primary imaging end point is the final post-PCI minimum stent area assessed by IVUS. The primary objective of this study is to assess the impact of IVUS guidance on the PCI treatment of complex lesions.