Fully Automated Quantitative Coronary Angiography Versus Optical Coherence Tomography Guidance for Coronary Stent Implantation (FLASH): Study Protocol for a Randomized Controlled Non-Inferiority 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 intra-observer 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, non-inferiority 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.

Intravascular ultrasound-guided versus angiography-guided percutaneous coronary intervention for acute myocardial infarction with cardiogenic shock.

The benefits of intravascular ultrasonography (IVUS)-guided percutaneous coronary intervention (PCI) in the clinical context of cardiogenic shock (CS) complicating acute myocardial infarction are lacking. We aimed to investigate the impact of IVUS-guided PCI in patients with AMI and CS. From the pooled data based on a series of Korean AMI registries during 2011-2020, we identified 1418 consecutive patients who underwent PCI with second generation drug-eluting stent (DES) for AMI and CS. The primary endpoint was the 1-year rate of target lesion failure (TLF), defined as the composite of cardiac death, target vessel myocardial infarction, and ischemic-driven target lesion revascularization. In total, 294 (20.7%) and 1124 (79.3%) underwent IVUS-guided and angiography-guided PCI with second generation DES implantation, respectively. The 1-year TLF was not significantly different between groups after IPTW analysis (hazard ratio 0.93, 95% confidence interval 0.65-1.34, p = 0.70). Additionally, the adjusted landmark analysis for TLF at 30 days and between 30 days and 1 year after PCI demonstrated no significant difference between the groups. In conclusion, in patients with AMI and CS who underwent PCI with second-generation DES, IVUS-guided PCI did not improve the 1-year TLF compared with angiography-guided PCI.Registration: URL:  http://cris.nih.go.kr . KCT0000863 and KCT0008355.

Distal Radial Access for Coronary Procedures in a Large Prospective Multicenter Registry: The KODRA Trial.

BACKGROUND: Distal radial access (DRA) as an alternative access route lacks evidence, despite its recent reputation. OBJECTIVES: The aim of this study was to evaluate the safety and feasibility of DRA on the basis of daily practice. METHODS: The KODRA (Korean Prospective Registry for Evaluating the Safety and Efficacy of Distal Radial Approach) trial was a prospective multicenter registry conducted at 14 hospitals between September 2019 and September 2021. The primary endpoints were the success rates of coronary angiography (CAG) and percutaneous coronary intervention (PCI). The secondary endpoints included successful distal radial artery puncture, access-site crossover, access site-related complications, bleeding events, and predictors of puncture failure. RESULTS: A total of 4,977 among 5,712 screened patients were recruited after the exclusion of 735 patients. The primary endpoints, the success rates of CAG and PCI via DRA, were 100% and 98.8%, respectively, among successful punctures of the distal radial artery (94.4%). Access-site crossover occurred in 333 patients (6.7%). The rates of distal radial artery occlusion and radial artery occlusion by palpation were 0.8% (36 of 4,340) and 0.8% (33 of 4,340) at 1-month follow-up. DRA-related bleeding events were observed in 3.3% of patients, without serious hematoma. Multilevel logistic regression analysis identified weak pulse (OR: 9.994; 95% CI: 7.252-13.774) and DRA experience <100 cases (OR: 2.187; 95% CI: 1.383-3.456) as predictors of puncture failure. CONCLUSIONS: In this large-scale prospective multicenter registry, DRA demonstrated high success rates of CAG and PCI, with a high rate of puncture success but low rates of distal radial artery occlusion, radial artery occlusion, bleeding events, and procedure-related complications. Weak pulse and DRA experience <100 cases were predictors of puncture failure. (Korean Prospective Registry for Evaluating the Safety and Efficacy of Distal Radial Approach [KODRA]; NCT04080700).

Optical coherence tomography-guided versus intravascular ultrasound-guided percutaneous coronary intervention in patients with acute myocardial infarction.

INTRODUCTION AND OBJECTIVES: Optical coherence tomography (OCT)-guided percutaneous coronary intervention (PCI) yields clinical outcomes comparable to intravascular ultrasound (IVUS)-guided PCI in patients with stable ischemic heart disease. However, there is a scarcity of data comparing the clinical outcomes of OCT-guided and IVUS-guided PCI in the setting of acute myocardial infarction (AMI). We sought to compare the clinical outcomes of OCT-guided vs IVUS-guided PCI for patients with AMI in the era of second-generation drug-eluting stent (DES). METHODS: We identified 5260 consecutive patients who underwent PCI with a second-generation DES for AMI under IVUS or OCT guidance from pooled data derived from a series of Korean AMI registries between 2011 and 2020. The primary endpoint was the 1-year rate of target lesion failure, defined as a composite of cardiac death, target vessel myocardial infarction, or ischemia-driven target lesion revascularization. RESULTS: A total of 535 (10.2%) and 4725 (89.8%) patients were treated under OCT and IVUS guidance, respectively. The 1-year target lesion failure rates were comparable between the OCT and IVUS groups before and after propensity score matching (hazard ratio, 0.92; 95%CI, 0.42-2.05, P=.84). The OCT utilization rate did not exceed 5% of total patients treated with second-generation DES implantation during the study period. The primary factors for the selection of OCT over IVUS were the absence of chronic kidney disease, non-left main vessel disease, single-vessel disease, stent diameter <3mm, and stent length ≤ 25mm. CONCLUSIONS: OCT-guided PCI in patients with AMI treated with a second-generation DES provided comparable clinical outcomes for 1-year target lesion failure compared with IVUS-guided PCI.

An Automatic-Vertical Profile Monitoring System for Fresh-Saline Water Zones in Coastal Aquifer.

Coastal aquifers are complex systems governed by fresh-saline water interactions and ocean tidal effects. The vertical electrical conductivity (EC) and temperature (T) are general indicators for detecting the fresh-saline water interface (FSI) and sea water intrusion in groundwater wells located in coastal aquifers. In this method brief, we developed a cost-effective Arduino-based automatic-vertical profile monitoring system (A-VPMS) to continuously record vertical EC and T in groundwater wells, with the aim of testing its effectiveness in spatiotemporal monitoring of the FSI in a coastal aquifer located in eastern Korea. By analyzing the high-density EC and T data obtained by the A-VPMS, we evaluated the characteristics of the FSI, such as depth and spatial distribution. Our established EC and T data collection method using the A-VPMS proved to be efficient and reliable, providing an excellent tool for fine-scale temporal and spatial understanding of sea water intrusion. The results of this study demonstrate the potential of the A-VPMS for continuous monitoring of the FSI in coastal aquifers, which is crucial for sustainable management of groundwater resources.

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.

Impacto del uso de ultrasonido intravascular en pacientes con infarto agudo de miocardio y alto riesgo isquémico / Impact of intravascular ultrasound in acute myocardial infarction patients at high ischemic risk

Introducción y objetivos: Hay falta de evidencia científica sobre el papel de la ecocardiografía intravascular intravascular (IVUS) para guiar procedimientos de intervencionismo coronario percutáneo (PCI) en pacientes con infarto agudo de miocardio (IAM) y alto riesgo isquémico. El objetivo de este trabajo fue investigar el impacto clínico a largo plazo de la PCI guiada por IVUS en pacientes con IAM y alto riesgo isquémico. Métodos: Se seleccionó una población de 8.890 pacientes sometidos con éxito a PCI con stent recubierto de segunda generación entre un total de 13.104 pacientes con IAM incluidos en el registro Korea Acute Myocardial Infarction Registry-National Institutes of Health. Los pacientes se clasificaron en 2 grupos según la presencia o no de alto riesgo isquémico, definido como la presencia de alguna de las siguientes condiciones: implante ≥ 3 stents, tratamiento ≥ 3 vasos, longitud total de stent> 60mm, PCI en el tronco, diabetes o enfermedad renal crónica. El objetivo primario fue el fracaso a 3 años de la lesión diana revascularizada, incluida muerte cardiaca, infarto de miocardio en el vaso objetivo y revascularización por isquemia relacionada con la lesión objetivo. Resultados: En 4.070 pacientes con IAM y alto riesgo isquémico, la PCI guiada por IVUS se asoció a un riesgo significativamente menor de fracaso a 3 años de la lesión objetivo revascularizada comparado con la PCI guiada por angiografía (6,7 frente a 12,0%; HR=0,54; intervalo de confianza del 95%, 0,41-0,72; p <0,001). Los resultados se mantuvieron tras el ajuste por posibles factores de confusión, ponderación de probabilidad inversa y emparejamiento por puntuación de propensión. Conclusiones: La PCI guiada por IVUS se asocia a una reducción significativa del fracaso a 3 años de la lesión objetivo revascularizada en pacientes con IAM y alto riesgo isquémico en los que se utilizó stent recubierto de segunda generación.(AU)

Introduction and objectives: Evidence for the role of intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) in patients at high ischemic risk of acute myocardial infarction (AMI) is lacking. This study aimed to investigate the long-term clinical impact of IVUS-guided PCI in patients at high ischemic risk of AMI. Methods: Among 13 104 patients with AMI enrolled in the Korea Acute Myocardial Infarction Registry-National Institutes of Health, we selected 8890 patients who underwent successful PCI with second-generation drug-eluting stent implantation and classified them into 2 groups based on whether or not they were at high ischemic risk or not, defined as any of the following: number of stents implanted ≥ 3, 3 vessels treated, ≥ 3 lesions treated, total stent length> 60mm, left main PCI, diabetes mellitus, and chronic kidney disease. The primary outcome was target lesion failure including cardiac death, target vessel myocardial infarction, and ischemia-driven target lesion revascularization at 3 years. Results: In 4070 AMI patients at high ischemic risk, IVUS-guided PCI (21.6%) was associated with a significantly lower risk of target lesion failure at 3 years (6.7% vs 12.0%; HR, 0.54; 95%CI, 0.41-0.72; P <.001) than angiography-guided PCI. The results were consistent after confounder adjustment, inversed probability weighting, and propensity score matching. Conclusions: In patients at high ischemic risk of AMI who underwent PCI with second-generation drug-eluting stent implantation, use of IVUS guidance was associated with a significant reduction in 3-year target lesion failure.(AU)

Impact of Intravascular Ultrasound-Guided Percutaneous Coronary Intervention in Patients With Acute Myocardial Infarction and Chronic Kidney Disease.

BACKGROUND: In the setting of acute myocardial infarction (AMI), there are no data regarding the benefits of intravascular ultrasound (IVUS) for chronic kidney disease (CKD) patients.Methods and Results: This study used data from the Korea Acute Myocardial Infarction Registry, a large, multicenter prospective cohort. We evaluated 1,759 patients with AMI and CKD, defined as estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2, and patients were classified into 2 groups: with and without IVUS. The primary outcome was target lesion failure (TLF) at 3 years. The hazard ratio (HR) of TLF according to eGFR was also analyzed. A total of 1,759 patients with AMI and CKD who underwent IVUS-guided PCI (19.2%) had a significantly lower risk of TLF at 3 years (8.9% vs. 15.3%; HR 0.55; 95% confidence interval [CI]: 0.38 to 0.81; P=0.002) than those who underwent angiography-guided PCI, regardless of their eGFR and the presence of end-stage renal disease (ESRD). The results were consistent after confounder adjustment and inversed probability weighting. CONCLUSIONS: In patients with CKD and AMI who underwent PCI with 2nd-generation DES implantation, the use of IVUS guidance was associated with a significant reduction in 3-year TLF and showed consistently favorable outcomes regardless of eGFR and ESRD.

A modified and rapid method for the single-well push-pull (SWPP) test using SF6, Kr, and uranine tracers.

In the present study, a single-well push-pull (SWPP) test was conducted with multi-component tracers, including inert gas (SF6 and Kr) and uranine (conservative), to understand the volatile/semi-volatile component transport characteristics in the groundwater system. In an SWPP test, it is essential to obtain an initial breakthrough curve (BTC) of the inert gas concentration at the beginning of the pulling stage to analyze the hydraulic properties of the groundwater system. As a result of the SWPP test using a proposed method in this study, physicochemical parameters of the groundwater and BTC of gas tracers and uranine were acquired simultaneously and successfully. In addition, on-site measurements of uranine, pCO2, and water quality data, such as electrical conductivity (EC), temperature, pH, and dissolved oxygen, were undertaken. Modification of an existing pCO2 measuring system allowed the gas samples to be collected, transported, and analyzed for inert gas components within a few hours. As a result, reliable and interpretable data with a recovery ratio of 26%, 85%, and 95% for SF6, Kr, and uranine, respectively, were obtained. The differences in the recovery ratio were utilized to identify the environmental system, whether it contains gas inside the isolated system (closed) or not (open), and to understand plume behavior characteristics in the experimental zone. By applying a two-dimensional advection-dispersion model to the acquired tracer test data and comparing the observed and computed tracer concentrations, helpful information was obtained on the hydraulic and transport characteristics of the targeted zone. This method can be extended to the design of dissolved CO2 transport monitoring of an aquifer above a CCS site.

Comparison of spasmolytic regimen for prevention of radial artery spasm during the distal radial approach: A single-center, randomized study.

Background: The distal radial approach (DRA) for coronary catheterization is increasingly being used worldwide yet the optimal medication regimen to prevent radial artery spasm (RAS), an important factor for the success of the procedure, remains unclear. The aim of this study is to examine the effectiveness of medication for preventing RAS via the DRA. Methods: This was a prospective, comparative randomized study including 400 patients who underwent coronary catheterization via DRA in single center by three experienced DRA operators. Patients were randomized to either nitroglycerin (NTG) injection (N = 200) or NTG plus verapamil (N = 200) to compare the effectiveness and safety of these regimens. Results: There were no differences between the groups in the changes in radial artery diameter at most spastic area (0.34 ± 0.20 in the NTG group, 0.35 ± 0.20 in the NTG plus verapamil group; P = 0.73). There was no difference between the groups in the ratio of patients without arm pain during the procedure (95.0% in the NTG group, 93.5% in the NTG plus verapamil group; P = 0.67). However, there was a greater reduction in diastolic blood pressure in the NTG plus verapamil group (-8.3 ± 7.9 mmHg) than in the NTG group (-6.6 ± 7.6 mmHg) (P = 0.03). Conclusion: Intra-arterial injection of NTG as a single agent is effective and safe in the prevention of RAS during coronary catheterization via the DRA compared with a cocktail regimen of NTG plus verapamil. Clinical trial registration: https://cris.nih.go.kr, identifier KCT0005177.

Early Invasive Strategy Based on the Time of Symptom Onset of Non-ST-Segment Elevation Myocardial Infarction.

BACKGROUND: A limitation of the current guidelines regarding the timing of invasive coronary angiography for patients with non-ST-segment elevation acute coronary syndrome is the randomization time. To date, no study has reported the clinical outcomes of invasive strategy timing on the basis of the time of symptom onset. OBJECTIVES: The aim of this study was to investigate the effect of invasive strategy timing from the time of symptom onset on the 3-year clinical outcomes of patients with non-ST-segment elevation myocardial infarction (NSTEMI). METHODS: Among 13,104 patients from the Korea Acute Myocardial Infarction Registry-National Institutes of Health, 5,856 patients with NSTE myocardial infarction were evaluated. The patients were categorized according to symptom-to-catheter (StC) time (<48 or ≥48 hours). The primary outcome was 3-year all-cause mortality. RESULTS: Overall, 3,919 patients (66.9%) were classified into the StC time <48 hours group. This group had lower all-cause mortality than the group with StC time ≥48 hours (7.3% vs 13.4%; P < 0.001). The lower risk for all-cause mortality in the group with StC time <48 hours group was consistent in all subgroups. Notably, emergency medical service use (HR: 0.31; 95% CI: 0.19-0.52) showed a lower risk for all-cause mortality than no emergency medical service use (HR: 0.54; 95% CI: 0.46-0.65; P value for interaction = 0.008). CONCLUSIONS: An early invasive strategy on the basis of StC time was associated with a decreased risk for all-cause mortality in patients with NSTEMI. Because the study was based on a prospective registry, the results should be considered hypothesis generating, highlighting the need for further research. (iCReaT Study No. C110016).

Impact of intravascular ultrasound in acute myocardial infarction patients at high ischemic risk.

INTRODUCTION AND OBJECTIVES: Evidence for the role of intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) in patients at high ischemic risk of acute myocardial infarction (AMI) is lacking. This study aimed to investigate the long-term clinical impact of IVUS-guided PCI in patients at high ischemic risk of AMI. METHODS: Among 13 104 patients with AMI enrolled in the Korea Acute Myocardial Infarction Registry-National Institutes of Health, we selected 8890 patients who underwent successful PCI with second-generation drug-eluting stent implantation and classified them into 2 groups based on whether or not they were at high ischemic risk or not, defined as any of the following: number of stents implanted ≥ 3, 3 vessels treated, ≥ 3 lesions treated, total stent length> 60mm, left main PCI, diabetes mellitus, and chronic kidney disease. The primary outcome was target lesion failure including cardiac death, target vessel myocardial infarction, and ischemia-driven target lesion revascularization at 3 years. RESULTS: In 4070 AMI patients at high ischemic risk, IVUS-guided PCI (21.6%) was associated with a significantly lower risk of target lesion failure at 3 years (6.7% vs 12.0%; HR, 0.54; 95%CI, 0.41-0.72; P <.001) than angiography-guided PCI. The results were consistent after confounder adjustment, inversed probability weighting, and propensity score matching. CONCLUSIONS: In patients at high ischemic risk of AMI who underwent PCI with second-generation drug-eluting stent implantation, use of IVUS guidance was associated with a significant reduction in 3-year target lesion failure. iCreaT study No. C110016.

Corrigendum: Safety and efficacy of contemporary drug-eluting stents in patients with ST-segment elevation myocardial infarction and a high ischemic risk.

[This corrects the article DOI: 10.3389/fcvm.2022.880351.].

Safety and Efficacy of Contemporary Drug-Eluting Stents in Patients With ST-Segment Elevation Myocardial Infarction and a High Ischemic Risk.

Background: In patients with ST-elevation myocardial infarction (STEMI) with a high risk of ischemic events, the safety and efficacy of drug-eluting stent (DES) are unclear. Methods: Based on the nationwide, multicenter, prospective registry, we selected 1,592 patients who underwent primary percutaneous coronary intervention (PCI) with everolimus-(EES) and zotarolimus-eluting stent (ZES) for STEMI with a high risk of an ischemic event. The occurrence of target lesion failure (TLF) for 3 years, defined as the composite of cardiac death, target vessel myocardial infarction (TV-MI), and ischemia-driven target lesion revascularization (ID-TLR), was evaluated. Results: The prevalence of high ischemic risk features was observed in 43.4% (2,744/6,325) of overall patients with STEMI. Among them, a total of 1,078 and 514 patients were treated with EES and ZES, respectively. At 3 years, the risk of TLF was not significantly different between the two groups (p = 0.93). In addition, the incidence of cardiac death, TV-MI, ID-TLR, and definite/probable stent thrombosis (ST) were also not different between the two groups. Moreover, elderly patients (age > 75 years) and PCI for the left main disease were identified as independent predictors of TLF. Conclusion: Implantation of EES or ZES provided comparable clinical outcomes in STEMI patients and high ischemic risks.

Comparisons of Prehospital Delay and Related Factors Between Acute Ischemic Stroke and Acute Myocardial Infarction.

Background Prehospital delay is an important contributor to poor outcomes in both acute ischemic stroke (AIS) and acute myocardial infarction (AMI). We aimed to compare the prehospital delay and related factors between AIS and AMI. Methods and Results We identified patients with AIS and AMI who were admitted to the 11 Korean Regional Cardiocerebrovascular Centers via the emergency room between July 2016 and December 2018. Delayed arrival was defined as a prehospital delay of >3 hours, and the generalized linear mixed-effects model was applied to explore the effects of potential predictors on delayed arrival. This study included 17 895 and 8322 patients with AIS and AMI, respectively. The median value of prehospital delay was 6.05 hours in AIS and 3.00 hours in AMI. The use of emergency medical services was the key determinant of delayed arrival in both groups. Previous history, 1-person household, weekday presentation, and interhospital transfer had higher odds of delayed arrival in both groups. Age and sex had no or minimal effects on delayed arrival in AIS; however, age and female sex were associated with higher odds of delayed arrival in AMI. More severe symptoms had lower odds of delayed arrival in AIS, whereas no significant effect was observed in AMI. Off-hour presentation had higher and prehospital awareness had lower odds of delayed arrival; however, the magnitude of their effects differed quantitatively between AIS and AMI. Conclusions The effects of some nonmodifiable and modifiable factors on prehospital delay differed between AIS and AMI. A differentiated strategy might be required to reduce prehospital delay.

Successful Primary Percutaneous Coronary Intervention without Stenting: Insight from Optimal Coherence Tomography.

For patients with acute myocardial infarction, current management guidelines recommend implantation of a drug-eluting stent, dual antiplatelet therapy (including potent P2Y12 inhibitors) for at least 1 year, and maintenance of life-long antiplatelet therapy. However, a pilot study showed favorable results with antithrombotic therapy without stent implantation when plaque erosion, not definite plaque rupture, was confirmed using optical coherence tomography (OCT), despite the patients having acute myocardial infarction. Here, we present a case where successful primary percutaneous coronary intervention was performed without stenting with the aid of OCT in a patient with ST-elevation myocardial infarction who developed thrombotic total occlusion of the right coronary artery.

Role of Intravascular Ultrasound-Guided Percutaneous Coronary Intervention in Optimizing Outcomes in Acute Myocardial Infarction.

Background The role of intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) is still unclear in patients with acute myocardial infarction acute myocardial infarction. This study aimed to evaluate the long-term impact of IVUS-guided PCI in patients with acute myocardial infarction. Methods and Results Among a total of 13 104 patients with acute myocardial infarction, enrolled in the Korea Acute Myocardial Infarction Registry-National Institutes of Health, we selected patients who underwent PCI with second-generation drug-eluting stent implantation. The primary outcome was the risk of target lesion failure at 3 years. Among the study population, 1887 patients (21.0%) underwent IVUS-guidance, and 7120 patients (79.0%) underwent angiography-guidance for second-generation drug-eluting stent implantation. IVUS-guided PCI was associated with a significantly lower risk of target lesion failure at 3 years (4.8% versus 8.0%; hazard ratio [HR], 0.59; 95% CI, 0.47 to 0.73; P<0.001) compared with angiography-guided PCI. The difference was driven mainly by a lower risk of cardiac death and target vessel myocardial infarction. The results were consistent after confounder adjustment by multiple sensitivity analyses. Moreover, quartile analysis of volume of IVUS use showed that higher IVUS use was associated with a decreased risk of 3-year target lesion failure (adjusted HR, 0.58; 95% CI, 0.45 to 0.75; P<0.001 for quartile 1 versus 4; P<0.001 for trend comparison across all quartiles). Conclusions In patients with acute myocardial infarction who underwent PCI with second-generation drug-eluting stent implantation, the use of IVUS guidance was associated with a significant reduction in 3-year target lesion failure, mainly driven by hard end points, such as cardiac death and target vessel myocardial infarction.

Physicochemical and isotopic properties of ambient aerosols and precipitation particles during winter in Seoul, South Korea.

The aim of this study was to characterize the physicochemical properties and microbial communities of particulate matter (PM) in Seoul, Korea. We collected long-term (2017-2019) precipitation samples and PM10 and PM2.5 monitoring data to determine the impact of soluble and insoluble chemical species on the soil surface. Ambient PM10 concentrations were higher than PM2.5 concentrations during the monitoring period, but both decreased during rainfall due to the washing effect of precipitation. PM2.5 particles had a "fluffy" shape and contained sulfur (0.2%), but suspended particles (SPs) contained many carbon particles (approximately 60%). Spherical particles containing metal oxides, Fe and Al, might be originated from coal combustion, wild fires, and metal-refining processes under high-temperature conditions. Dissolved ions in precipitation included those eluted from salts and coal combustion based on the correlation coefficients of Na and Cl (R = 0.953) and F and NO3 (R = 0.706). The δ15N-NO3 and δ34S-SO4 of precipitation were enriched as the atmospheric temperature decreased from 9.8 to -1.6°C, implying the influence of domestic coal combustion. Backward trajectories showed that, in winter, air parcels passed through industrialized cities from China to South Korea. The microbial communities associated with PM were strongly influenced by atmospheric conditions. Proteobacteria (range from 4.6 to 76.7%) and Firmicutes (range from 6.0 to 91.4%) were the most dominant phyla and were significantly affected by changes in the PM2.5 environment. The results indicate that the acidity of precipitation and the composition of aerosols were affected by fossil fuel combustion and mineral dust, and that atmospheric conditions may change as PM2.5 concentrations increase.