• The Korean Journal of Emergency Medical Services
• /
• v.25 no.1
• /
• pp.243-249
• /
• 2021

A decrease in coronary blood flow leads to an imbalance between the supply of oxygen to the myocardium and its demand, and reversible or irreversible damage to the myocardium could occur depending on the severity of the resultant ischemia and the duration of the imbalance. This imbalance results in a cascade of ischemic reactions in the following order: metabolic abnormalities, diastolic dysfunction, systolic dysfunction, and electrocardiogram changes. Variant angina is caused by the closure of the coronary artery due to reversible coronary artery spasm, resulting in myocardial ischemia and subsequent chest pain as a clinical symptom. Variant angina may be observed as ST segment elevation in electrocardiogram measured when present in chest pain. However, 12-lead electrocardiogram performed after the patient's chest pain resolves does not help in the diagnosis. Since the duration of chest pain appears to be <15 minutes, it is important to perform the 12-lead electrocardiogram when clinical symptoms are present. If nitroglycerin is administered without performing 12-lead electrocardiogram by 119 pre-hospital paramedics, the chest pain would be resolved, making it impossible to identify changes in the ST segment. Before administration of nitroglycerin, changes in the ST segment must be recorded by performing 12-lead electrocardiogram.

• Korean Journal of Clinical Pharmacy
• /
• v.6 no.2
• /
• pp.32-40
• /
• 1996

The electrophysiological effects of benzopyran potassium channel openers (PCOs: lemakalim, KR-30450 and KR-30818) on the ischemia/reperfusion-induced arrythmias were investigated. In anesthetized rats, subjected to 45 min occlusion of the left anterior descending coronary artery (LAD) followed by 90 min reperfusion, ventricular arrythmias were identified according to the Lambeth Conventions by lead II ECG. Rats were intravenously given vehicle ($1\%$ DMSO), lemakalim, KR-30450, and KR-30818 alone or in combination with a selective $K_{ATP}$ blocker glibenclamide, 30 min prior to coronary occlusion. Compared to vehicle, lemakalim ($30{\mu}g/kg$ i.v.), the active enantiomer of cromakalim, had a tendancy to increase the duration of ventricular tachycardia (Vl) and ventricular fibrillation (VF), the number of premature ventricular complexes (PVC) and the incidence of VF, especially in the early post-occlusion peroid ($0\~15$ min), while increasing ST-segment elevation. Both KR-30450 ($30{\mu}g/kg$, i.v.) and KR-30818 (30, $100{\mu}g/kg$, i.v.) showed similar proarrhythmic effects to lemakalim (PVC, duration of VT, and incidence of VF) with a tendancy to decrease the duration of VF and ST-segment elevation. Unlike other PCOs, however, glibenclamide (0.3, 1.0 mg/kg) had opposite effects on the induction of arrhythmias (PVC, the duration of VF); it had a tendancy to increase the duration of VT with a slight elevation of ST-segment. It seems likely that glibenclamide (0.3 mg/kg, i.v.), reduced the effects of lemakalim or KR-30450 ($30{\mu}g/kg$, i.v.) on arrhythmias (PVC, VT, VF and ST-segment). These results indicate that, in the coronary occluded rat model of ischemia, lemikuiln and KR-30450 exert a proarrhythmic activity, the effect being considered related to the opening of KATP channel.

• Journal of Medicine and Life Science
• /
• v.21 no.2
• /
• pp.31-39
• /
• 2024

This study was conducted to determine whether level-1 emergency medical technicians (EMTs) can adequately recognize ST-segment elevation myocardial infarction (STEMI) in the emergency department (ED) and whether their ability to do so differs from that of emergency medicine physicians (EMP). From December 2022 to November 2023, patients aged 20 years or older visiting the ED with chief complaints suggesting acute coronary syndrome (ACS) were enrolled. As soon as the patient arrived at the ED, a level-1 EMT conducted a 12-lead electrocardiogram (ECG) to assess STEMI; an EMP subsequently assessed whether to activate the percutaneous coronary intervention team. Demographic characteristics, test results, and final diagnoses were collected from the medical records. Among the 723 patients with case report forms, 720 were included in the analysis. These were categorized as follows: 117 (16.3%) with STEMI, 159 (22.1%) with non-ST-segment elevation ACS, and 444 (61.7%) with other conditions. STEMI was correctly recognized in 100 patients (91.7%) by level-1 EMTs and in 104 patients (95.4%) by EMPs (kappa=0.646). EMTs with less than 1 year of ED work experience correctly recognized 60 out of 67 STEMI patients (89.6%), which was comparable with the EMPs who recognized 65 out of 67 STEMI patients (97.0%, kappa=0.614). EMTs with more than 1 year of ED work correctly recognized 40 out of 42 STEMI patients (95.2%), and therefore performed better than EMPs, who recognized 39 out of 42 STEMI patients (92.9%, kappa=0.727). The level-1 EMTs adequately recognized STEMI using a 12-lead ECG and were in substantial agreement with the evaluations of the EMPs.

• Journal of the Korean Society of Radiology
• /
• v.83 no.1
• /
• pp.28-41
• /
• 2022

Acute coronary syndrome involves three types of coronary artery disease associated with sudden rupture of coronary artery plaque, and has a clinical presentation ranging from ST-segment elevation myocardial infarction (STEMI) to non-ST-segment elevation myocardial infarction (NSTEMI) or unstable angina. Cardiac CT can help quantify and characterize atherosclerotic plaques. According to a previous study, low-attenuation plaque, napkin ring sign, positive remodeling, spotty calcification, and increased perivascular fat attenuation are associated with plaque ruptures on cardiac CT. Therefore, coronary artery stenosis, as well as acute coronary artery syndrome, can be diagnosed using cardiac CT.

• Journal of Cardiovascular Imaging
• /
• v.30 no.3
• /
• pp.197-201
• /
• 2022

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.50 no.4
• /
• pp.201-207
• /
• 2001

This paper describes an automated detection algorithm of ST-T episodes using global curvature which can connect the isoelectric level in ECG and can eliminate not only the slope of ST segment, but also difference of the baseline and global curve. This above method of baseline correction is very faster than the classical baseline correction methods. The optimal values of parameters for baseline correction were found as the value having the highest detection rate of ST episode. The features as input of backpropagation Neural Network were extracted from the whole ST segment. The European ST-T database was used as training and test data. Finally, ST elevation, ST depression and normal ST were classified. The average ST episode sensitivity and predictivity were 85.42%, 80.29%, respectively. This result shows the high speed and reliability in ST episode detection. In conclusion, the proposed method showed the possibility in various applications for the Holter system.

• Korean Journal of Adult Nursing
• /
• v.27 no.1
• /
• pp.83-93
• /
• 2015

Purpose: This study was to investigate the relationship among the symptom recognition, health behavior compliance, and the hospital arrival time to identify factors influencing the hospital arrival time in patient with acute myocardial infarction (AMI). Methods: The subjects of this study were 200 patients with AMI in C hospital in D city. Data were analyzed using descriptive statistics, independent t-test, One way ANOVA, Pearson's correlation coefficients, and stepwise multiple liner regression tests. Results: Level of symptom recognition and health behavior compliance was low. The median value of hospital arrival time was 4.48 hours (ST-segment Elevation Ml was 2.43 hours and Non ST-segment Elevation MI was 7.83 hours). Among the studied factors, only symptom recognition had a statistically significant positive correlation with health behavior compliance (r=0.38, p<.001). Factors influencing the hospital arrival time were MI classification, diabetes mellitus (DM) and transport vehicle to the 1st hospital, and they accounted for 13% of the variance for hospital arrival time in AMI patients. Conclusion: To prevent the delay of hospital arrival time in MI patients, a more robust nursing strategic intervention according to MI classification and DM is necessary; further education on the importance of transportation utilization is also mandated.

• Korean Circulation Journal
• /
• v.52 no.4
• /
• pp.280-287
• /
• 2022

Several studies have shown the benefit of complete revascularization (CR) over culprit-only percutaneous coronary intervention (PCI) in patients with ST-segment elevated myocardial infarction (STEMI) and multivessel disease (MVD). Nevertheless, optimal strategy to select targets for non-culprit PCI has not been clarified. In this paper, we critically discuss and compare the safety and efficacy of different strategies for CR in patients with STEMI and MVD using a Bayesian network meta-analysis including all previous randomized controlled trials (RCTs). In Bayesian network meta-analysis of 13 RCTs, culprit-only PCI was associated with higher risk of major adverse cardiac events (MACE), compared with angiography-guided or fractional flow reserve (FFR)-guided CR strategies. However, there was no significant difference between angiography-guided and FFR-guided CR strategies in the risk of MACE and its individual components including all-cause death, cardiac death, myocardial infarction (MI), and revascularization. These evidence support that both angiography-guided and FFR-guided complete revascularization strategies would be reasonable treatment option in patients with STEMI and MVD. If the non-culprit lesion is severe on visual assessment, angiography-guided PCI can be considered. If the non-culprit lesion is intermediate in severity or unclear based on visual assessment, FFR-guided strategy can be used as a reliable and objective tool, providing similar benefits with less stents compared with an angiography-guided strategy. Further RCT is needed to evaluate direct comparison between angiography-guided and FFR-guided CR strategies in patients with STEMI and MVD. Ongoing FRAME-AMI trial (NCT02715518) will provide more evidence regarding this issue.

• Korean Circulation Journal
• /
• v.48 no.11
• /
• pp.989-999
• /
• 2018

Background and Objectives: We aimed to compare outcomes of complete revascularization (CR) versus culprit-only revascularization for ST-segment elevation myocardial infarction (STEMI) and multivessel disease (MVD) in the $2^{nd}$ generation drug-eluting stent (DES) era. Methods: From 2009 to 2014, patients with STEMI and MVD, who underwent primary percutaneous coronary intervention (PCI) using a $2^{nd}$ generation DES for culprit lesions were enrolled. CR was defined as PCI for a non-infarct-related artery during the index admission. Major adverse cardiovascular event (MACE) was defined as cardiovascular (CV) death, non-fatal myocardial infarction, target lesion revascularization, or heart failure during the follow-up year. Results: In total, 705 MVD patients were suitable for the analysis, of whom 286 (41%) underwent culprit-only PCI and 419 (59%) underwent CR during the index admission. The incidence of MACE was 11.5% in the CR group versus 18.5% in the culprit-only group (hazard ratio [HR], 0.56; 95% confidence interval [CI], 0.37-0.86; p<0.01; adjusted HR, 0.64; 95% CI, 0.40-0.99; p=0.04). The CR group revealed a significantly lower incidence of CV death (7.2% vs. 12.9%; HR, 0.51; 95% CI, 0.31-0.86; p=0.01 and adjusted HR, 0.57; 95% CI; 0.32-0.97; p=0.03, respectively). Conclusions: CR was associated with better outcomes including reductions in MACE and CV death at 1 year of follow-up compared with culprit-only PCI in the $2^{nd}$ generation DES era.

• Journal of Yeungnam Medical Science
• /
• v.31 no.2
• /
• pp.122-126
• /
• 2014

Coronary vasospasm is one of the fatal complications that may occur in patients undergoing open heart surgery. To date, however, there are not many cases in this series and no definite pathophysiology has been documented. We experienced a case of coronary artery vasospasm after atrial septal defect (ASD) surgery and then successfully treated it with both transbrachial intraaortic balloon pump and percutaneous cardiopulmonary support. Only several hours after ASD surgery, the patient exhibited the cardiovascular collapse, the ST-segment elevation, followed by ventricular fibrillation and normal coronary angiography findings. It is important to make a differential diagnosis of coronary artery vasospasm in patients presenting with ST-segment elevation who had no notable coronary artery diseases. This case indicates that clinicians should be aware of the possibility that the coronary artery vasospasm may also occur in patients undergoing ASD surgery.