Fully automated quantitative coronary angiography versus optical coherence tomography guidance for coronary stent implantation (FLASH): Study protocol for a randomized controlled noninferiority trial.

BACKGROUND: Artificial intelligence-based quantitative coronary angiography (AI-QCA) has been developed to provide a more objective and reproducible data about the severity of coronary artery stenosis and the dimensions of the vessel for intervention in real-time, overcoming the limitations of significant inter- and intraobserver variability, and time-consuming nature of on-site QCA, without requiring extra time and effort. Compared with the subjective nature of visually estimated conventional CAG guidance, AI-QCA guidance provides a more practical and standardized angiography-based approach. Although the advantage of intravascular imaging-guided PCI is increasingly recognized, their broader adoption is limited by clinical and economic barriers in many catheterization laboratories. METHODS: The FLASH (fully automated quantitative coronary angiography versus optical coherence tomography guidance for coronary stent implantation) trial is a randomized, investigator-initiated, multicenter, open-label, noninferiority trial comparing the AI-QCA-assisted PCI strategy with optical coherence tomography-guided PCI strategy in patients with significant coronary artery disease. All operators will utilize a novel, standardized AI-QCA software and PCI protocol in the AI-QCA-assisted group. A total of 400 patients will be randomized to either group at a 1:1 ratio. The primary endpoint is the minimal stent area (mm2), determined by the final OCT run after completion of PCI. Clinical follow-up and cost-effectiveness evaluations are planned at 1 month and 6 months for all patients enrolled in the study. RESULTS: Enrollment of a total of 400 patients from the 13 participating centers in South Korea will be completed in February 2024. Follow-up of the last enrolled patients will be completed in August 2024, and primary results will be available by late 2024. CONCLUSION: The FLASH is the first clinical trial to evaluate the feasibility of AI-QCA-assisted PCI, and will provide the clinical evidence on AI-QCA assistance in the field of coronary intervention. CLINICAL TRIAL REGISTRATION: URL: https://www. CLINICALTRIALS: gov. Unique identifier: NCT05388357.

Invasive physiologic assessment of coronary artery stenosis by resting full-cycle ratio and fractional flow reserve: a prospective observational study.

Resting full-cycle ratio (RFR), an alternative to fractional flow reserve (FFR) for evaluating intermediate coronary artery stenosis, helps reduce patients' time, cost, and discomfort. However, the validation data for RFR and FFR are lacking. We aimed to assess the diagnostic accuracy of RFR and FFR and evaluate effective decision-making for revascularization using their values. Patients subjected to an invasive physiological study for intermediate coronary artery stenosis in Yongin Severance hospital between October 2020 and April 2022 were prospectively and consecutively recruited. We evaluated the correlation between RFR and FFR measurements and the diagnostic performance of RFR (≤ 0.89) versus FFR (≤ 0.80). In all, 474 intermediate coronary stenosis lesions from 400 patients were evaluated using RFR and FFR values. There was a strong linear relationship between RFR and FFR (r = 0.75, 95% CI 0.70-0.78, p < 0.01). Comparing diagnostic performance between RFR and FFR, RFR demonstrated diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 85.0%, 80.0%, 86.7%, 67.1%, and 92.7%, respectively. We analyzed the RFR value in the hyperemia zone (0.86-0.93) according to positive (RFR: 0.86-0.89) and negative (RFR: 0.90-0.93) areas. PPV in positive area is 47.8% (95% Confidence Interval [CI]: 33.8% to 62.0%) and NPV in negative area is 87.7% (95% CI: 80.3% to 93.1%). Excellent correlation exists between RFR and FFR and the diagnostic value of RFR without hyperemia compared with FFR in establishing the accurate functional significance of coronary artery stenosis was shown. RFR alone could evaluate the functional significance of coronary artery stenosis without unnecessary hyperemia, except in the positive area.Trial registration: URL: http://trialsearch.who.int ; Unique identifier: KCT0005255.

Assessment of the conventional radial artery with optical coherent tomography after the snuffbox approach.

BACKGROUND: This study aimed to evaluate acute injuries of the radial artery (RA) using optical coherence tomography (OCT) in patients who underwent coronary intervention via the snuffbox approach. METHODS: Forty-six patients, who underwent coronary intervention and assessment of the conventional RA using OCT via the snuffbox approach, were enrolled from two university hospitals between August 2018 and August 2019. RESULTS: The mean age of the patients was 65.1 years. In this study population, 6-French (Fr) sheaths were used. The mean diameter of the conventional RA was 2.89 ± 0.33 mm, and the mean lumen area of the conventional RA was 6.68 ± 1.56 mm2. Acute injuries of the conventional RA, after the snuffbox approach, were observed in 5 (10.9%) patients. Intimal tear was observed in the RA in 1 (2.2%) case. Intraluminal thrombi, without vessel injuries, were detected in the RA in 4 (8.7%) cases. However, medial dissection was not observed in the OCT analysis. CONCLUSIONS: This retrospective OCT-based study showed that the diameter of the conventional RA was 2.89 mm and acute vessel injury of the conventional RA was rare in patients who underwent coronary intervention via the snuffbox approach.

Comparative overview of ST-elevation myocardial infarction epidemiology, demographics, management, and outcomes in five Asia-Pacific countries: a meta-analysis.

The aim of this study is to gain insight into the differences in demographics of ST-elevation myocardial infarction (STEMI) patients in Asia-Pacific, as well as inter-country variation in treatment and mortality outcomes. Systematic review of published studies and reports from known registries in Australia, Japan, Korea, Singapore, and Malaysia that began data collection after the year 2000. Supplementary self-report survey questionnaire on public health data answered by representative cardiologists working in these countries. Twenty studies comprising of 158 420 patients were included in the meta-analysis. The mean age was 61.6 years. Chronic kidney disease prevalence was higher in Japan, while dyslipidaemia was low in Korea. Use of aspirin, P2Y12 inhibitors, and statins were high throughout, but ACEi/ARB and ß-blocker prescriptions were lower in Japan and Malaysia. Reperfusion strategies varied greatly, with high rates of primary percutaneous coronary intervention (pPCI) in Korea (91.6%), whilst Malaysia relies far more on fibrinolysis (72.6%) than pPCI (9.6%). Similarly, mortality differed, with 1-year mortality from STEMI was considerably greater in Malaysia (17.9%) and Singapore (11.2%) than in Korea (8.1%), Australia (7.8%), and Japan (6.2%). The countries were broadly similar in development and public health indices. Singapore has the highest gross national income and total healthcare expenditure per capita, whilst Malaysia has the lowest. Primary PCI is available in all countries 24/7/365. Despite broadly comparable public health systems, differences exist in patient profile, in-hospital treatment, and mortality outcomes in these five countries. Our study reveals areas for improvements. The authors advocate further registry-based multi-country comparative studies focused on the Asia-Pacific region.