Gallic Acid Inhibits Proliferation and Migration of Smooth Muscle Cells in a Pig In-Stent Restenosis Model / 전남의대학술지

In-stent restenosis (ISR) develops primarily due to neointimal hyperplasia. Gallic acid (GA) has anti-inflammatory, antioxidant, and cardioprotective effects. This study sought to investigate the effects of GA on neointimal hyperplasia and proliferation and migration of vascular smooth muscle cells (VSMCs) in a pig ISR model. In vitro proliferation and migration experiments were confirmed, after VSMCs were treated with plateletderived growth factor (PDGF-BB) and GA (100 µM) using a 3‑(4,5‑dimethylthiazol)‑ 2,5‑diphenyltetrazolium bromide (MTT) assay and a scratch wound assay for 24 hours and 48 hours. A bare metal stent (BMS) was implanted in the pig coronary artery to induce ISR with overdilation (1.1-1.2:1), and GA (10 mg/kg/day) was administered for 4 weeks. At the 4-week follow-up, optical coherence tomography (OCT) and histopathological analyses were performed. GA decreased the proliferation of VSMCs by PDGF-BB for 24 hours (89.24±24.56% vs. 170.04±19.98%, p＜0.001) and 48 hours (124.87±7.35% vs. 187.64±4.83%, p＜0.001). GA inhibited the migration of VSMCs induced by PDGF-BB for 24 hours (26.73±2.38% vs. 65.38±9.73%, p＜0.001) and 48 hours (32.96±3.04% vs. 77.04±10.07%, p＜0.001). Using OCT, % neointimal hyperplasia was shown to have significantly decreased in the GA group compared with control vehicle group (28.25± 10.07% vs. 37.60±10.84%, p＜0.001). GA effectively reduced neointimal hyperplasia by inhibiting the proliferation and migration of VSMCs in a pig ISR model. GA could be a potential treatment strategy for reducing ISR after stent implantation.

Clinical Outcome after Everolimus-Eluting Stent Implantation for Small Vessel Coronary Artery Disease: XIENCE Asia Small Vessel Study / 전남의대학술지

There are limited data on outcomes after implantation of everolimus-eluting stents (EES) in East Asian patients with small vessel coronary lesions. A total of 1,600 patients treated with XIENCE EES (Abbott Vascular, CA, USA) were divided into the small vessel group treated with one ≤2.5 mm stent (n=119) and the non-small vessel group treated with one ≥2.75 mm stent (n=933). The primary end point was a patient-oriented composite outcome (POCO), a composite of all-cause death, myocardial infarction (MI), and any repeat revascularization at 12 months. The key secondary end point was a device-oriented composite outcome (DOCO), a composite of cardiovascular death, target-vessel MI, and target lesion revascularization at 12 months. The small vessel group was more often female, hypertensive, less likely to present with ST-elevation MI, and more often treated for the left circumflex artery, whereas the non-small vessel group more often had type B2/C lesions, underwent intravascular ultrasound, and received unfractionated heparin. In the propensity matched cohort, the mean stent diameter was 2.5±0.0 mm and 3.1±0.4 mm in the small and non-small vessel groups, respectively. Propensity-adjusted POCO at 12 months was 6.0% in the small vessel group and 4.3% in the non-small vessel group (p=0.558). There was no significant difference in DOCO at 12 months (small vessel group: 4.3% and non-small vessel group: 1.7%, p=0.270).Outcomes of XIENCE EES for small vessel disease were comparable to those for non-small vessel disease at 12-month clinical follow-up in real-world Korean patients.

Time to presentation and mortality outcomes among patients with diabetes and acute myocardial infarction

Background/Aims@#Due to limited real-world evidence on the association between time to presentation (T2P) and outcomes following acute myocardial infarction and diabetes (AMI-DM), we investigated the characteristics of patients with AMI-DM and their outcomes based on their T2P. @*Methods@#4,455 patients with AMI-DM from a Korean nationwide observational cohort (2011–2015) were divided into early and late presenters according to symptom-to-door time. The effects of T2P on three-year all-cause mortality were estimated using inverse probability of treatment weighting (IPTW) and survival analysis. @*Results@#The incidence of all-cause mortality was consistently higher in late presenters than in early presenters (11.4 vs. 17.2%; p < 0.001). In the IPTW-adjusted dataset, the incidence of all-cause mortality was numerically higher in late presenters than in early presenters (9.1 vs. 12.4%; p = 0.072). In the survival analysis, the cumulative incidence of all-cause mortality was significantly higher in late presenters than in early presenters before and after IPTW. In the subgroup with ST-elevation myocardial infarction, late presenters had a higher incidence of cardiac death than early presenters before (4.8 vs. 10.5%; p < 0.001) and after IPTW (4.2 vs. 9.7%; p = 0.034). In the initial glycated hemoglobin (HbA1c)-stratified analysis, these effects were attenuated in patients with HbA1c ≥ 9.0% before (adjusted hazard ratio [HR]: 1.45, 95% confidence interval [CI]: 0.80-2.64) and after IPTW (adjusted HR: 0.82, 95% CI: 0.40-1.67). @*Conclusions@#Late presentation was associated with higher mortality in patients with AMI-DM; therefore, multifaceted and systematic interventions are needed to decrease pre-hospital delays.

Preliminary Investigation on Efficacy and Safety of Substance P-Coated Stent for Promoting Re-Endothelialization: A Porcine Coronary Artery Restenosis Model

BACKGROUND@#Current polymer-based drug-eluting stents (DESs) have fundamental issues about inflammation and delayed re-endothelializaton of the vessel wall. Substance-P (SP), which plays an important role in inflammation and endothelial cells, has not yet been applied to coronary stents. Therefore, this study compares poly lactic-co-glycolic acid (PLGA)-based everolimus-eluting stents (PLGA-EESs) versus 2-methacryloyloxyethyl phosphorylcholine (MPC)-based SP-eluting stents (MPC-SPs) in in-vitro and in-vivo models. @*METHODS@#The morphology of the stent surface and peptide/drug release kinetics from stents were evaluated. The invitro proliferative effect of SP released from MPC-SP is evaluated using human umbilical vein endothelial cell. Finally, the safety and efficacy of the stent are evaluated after inserting it into a pig’s coronary artery. @*RESULTS@#Similar to PLGA-EES, MPC-SP had a uniform surface morphology with very thin coating layer thickness (2.074 lm). MPC-SP showed sustained drug release of SP for over 2 weeks. Endothelial cell proliferation was significantly increased in groups treated with SP (n = 3) compared with the control (n = 3) and those with everolimus (n = 3) (SP:118.9 ± 7.61% vs. everolimus: 64.3 ± 12.37% vs. the control: 100 ± 6.64%, p < 0.05). In the animal study, the percent stenosis was higher in MPC-SP group (n = 7) compared to PLGA-EES group (n = 7) (MPC-SP: 28.6 ± 10.7% vs. PLGAEES: 16.7 ± 6.3%, p < 0.05). MPC-SP group showed, however, lower inflammation (MPC-SP: 0.3 ± 0.26 vs. PLGAEES: 1.2 ± 0.48, p < 0.05) and fibrin deposition (MPC-SP: 1.0 ± 0.73 vs. PLGA-EES: 1.5 ± 0.59, p < 0.05) around the stent strut. MPC-SP showed more increased expression of cluster of differentiation 31, suggesting enhanced reendothelialization. @*CONCLUSION@#Compared to PLGA-EES, MPC-SP demonstrated more decreased inflammation of the vascular wall and enhanced re-endothelialization and stent coverage. Hence, MPC-SP has the potential therapeutic benefits for the treatment of coronary artery disease by solving limitations of currently available DESs.

Ghrelin Modifies the Impact of Life Stress on Suicidality in Patients With Acute Coronary Syndrome

Objective@#This study investigated associations of life stressors and serum ghrelin levels with suicidal ideation (SI), and evaluated the potential mediating effect of ghrelin on associations between life stressors and SI in patients with acute coronary syndrome (ACS). @*Methods@#In total, 969 ACS patients recruited from a tertiary university hospital in Korea within 2 weeks of disease onset were evaluated in terms of life stressors (using the List of Threatening Events Questionnaire), serum ghrelin levels, and SI (using the “suicidal thoughts” item of the Montgomery–Asberg Depression Rating Scale). Covariates included sociodemographics, depression, vascular risk factors, and disease severity. After 1 year, 711 patients were re-evaluated in terms of SI; logistic regression was performed with adjustment for covariates. @*Results@#Life stressors were significantly associated with SI at baseline and follow-up. Serum ghrelin showed no such associations, but high levels thereof mediated associations of life stressors with SI; significant interaction terms were also observed after adjustment for covariates. @*Conclusion@#By evaluating life stressors and serum ghrelin levels, clinical prediction of SI in the acute and chronic phases of ACS could be improved.

Possible Link between Serotonin and Interleukin 18 on Suicidality in Patients with Acute Coronary Syndrome

Objective@#We investigated effects of serum serotonin and interleukin 18 levels on suicidal ideation (SI) at acute and chronic phases of acute coronary syndrome (ACS). @*Methods@#Recent-onset 969 ACS patients were evaluated for serum serotonin and interleukin 18 levels; and SI by the“suicidal thoughts” item of the Montgomery–Åsberg Depression Rating Scale. After 1-year, 711 patients were re-evaluated for SI. Logistic regression models were used adjustment for potential covariates. @*Results@#Associations between serum interleukin 18 and SI at both phases were significant only in the lower serotonin group. @*Conclusion@#By evaluating serum serotonin and interleukin 18 levels, the clinical prediction of SI of ACS may be improved.

Effect Modification of Cortisol on the Associations Between Obsessive-Compulsive Symptoms on Suicidality in Patients With Acute Coronary Syndrome

Objective@#Obsessive-compulsive symptoms (OCS) and suicidal ideation (SI) are common in patients with acute coronary syndrome (ACS). This study investigated the associations of OCS and serum cortisol levels with SI, and further evaluated the possible modifying effects of cortisol on the associations between OCS and SI in acute and chronic phases of ACS. @*Methods@#In total, 969 ACS patients were recruited from a tertiary university hospital in Korea within 2 weeks of disease onset and evaluated in terms of OCS (using the OCS dimension of the Symptom Checklist-90–Revised), serum cortisol levels, and SI (using the “suicidal thoughts” item of the Montgomery–Åsberg Depression Rating Scale). Covariates included sociodemographics, depression, vascular risk factors, and disease severity. After 1 year, 711 patients were re-evaluated in terms of SI. Logistic regression analysis was performed with adjustment for covariates. @*Results@#Higher OCS was significantly associated with SI both at baseline and follow-up. Serum cortisol showed no such association, but modified the association between OCS and SI. That was the associations were significant only in the higher but not in the lower serum cortisol levels, with significant interaction terms after adjusted for relevant covariates. @*Conclusion@#Evaluating OCS and serum cortisol levels at the acute phase could improve the accuracy of clinical predictions of SI both in the acute and chronic phases of ACS.

Preclinical Evaluation of an Everolimus-Eluting Bioresorbable Vascular Scaffold Via a Long-Term Rabbit Iliac Artery Model

BACKGROUND@#Biodegradable poly (l-lactic acid) (PLLA), a bio safe polymer with a large elastic modulus, is widely used in biodegradable medical devices. However, because of its poor mechanical properties, a PLLA strut must be made twice as thick as a metal strut for adequate blood vessel support. Therefore, the mechanical properties of a drug-eluting metal-based stents (MBS) and a bioresorbable vascular scaffolds (BVS) were evaluated and their safety and efficacy were examined via a long-term rabbit iliac artery model. @*METHODS@#The surface morphologies of the MBSs and BVSs were investigated via optical and scanning electron microscopy. An everolimus-eluting (EE) BVS or an EE-MBS was implanted into rabbit iliac arteries at a 1.1:1 stent-toartery ratio. Twelve months afterward, stented iliac arteries from each group were analyzed via X-ray angiography, optical coherence tomography (OCT), and histopathologic evaluation. @*RESULTS@#Surface morphology analysis of the EE coating on the MBS confirmed that it was uniform and very thin (4.7 lm). Comparison of the mechanical properties of the EE-MBS and EE-BVS showed that the latter outperformed the former in all aspects (radial force (2.75 vs. 0.162 N/mm), foreshortening (0.24% vs. 1.9%), flexibility (0.52 vs. 0.19 N), and recoil (3.2% vs. 6.3%). At all time points, the percent area restenosis was increased in the EE-BVS group compared to the EE-MBS group. The OCT and histopathological analyses indicate no significant changes in strut thickness. @*CONCLUSION@#BVSs with thinner struts and shorter resorption times should be developed. A comparable long-term safety/efficacy evaluation after complete absorption of BVSs should be conducted.

Predictors of Progression of Tricuspid Regurgitation in Patients with Persistent Atrial Fibrillation / 전남의대학술지

Previous studies have shown that tricuspid regurgitation (TR) can be developed in patients with atrial fibrillation (AF) due to annular dilatation. This study aimed to investigate the incidence and predictors of the progression of TR in patients with persistent AF. A total of 397 patients (66.9±11.4 years, 247 men; 62.2%) with persistent AF were enrolled between 2006 and 2016 in a tertiary hospital, and 287 eligible patients with follow-up echocardiography were analyzed. They were divided into two groups according to TR progression (progression group [n=68, 70.1±10.7 years, 48.5% men] vs. non-progression group [n=219, 66.0±11.3 years, 64.8% men]). Among 287 patients in the analysis, 68 had worsening TR severity (23.7%). Patients in the TR progression group were older and more likely to be female. Patients with left ventricular ejection fraction ＜50% were less frequent in the progression group than those in the non-progression group (7.4% vs. 19.6%, p=0.018). Patients with mitral valve disease were more frequent in the progression group. Multivariate analysis with COX regression demonstrated independent predictors of TR progression, including left atrial (LA) diameter ＞54 mm (HR 4.85, 95%CI 2.23-10.57, p＜0.001), E/e’ (HR 1.05, 95%CI 1.01-1.10, p=0.027), and no use of antiarrhythmic agents (HR 2.20, 95%CI 1.03-4.72, p=0.041). In patients with persistent AF, worsening TR was not uncommon. The independent predictors of TR progression turned out to be greater LA diameter, higher E/e’, and no use of antiarrhythmic agents.

Baseline Lipoprotein(a) Levels and Long-Term Cardiovascular Outcomes After Acute Myocardial Infarction

Background@#Lipoprotein(a) is a known independent risk factor for atherosclerotic cardiovascular disease. However, the prognostic impact of the baseline lipoprotein(a) levels on long-term clinical outcomes among patients with acute myocardial infarction remain unclear. @*Methods@#We analyzed 1,908 patients with acute myocardial infarction from November 2011 to October 2015 from a single center in Korea. They were divided into 3 groups according to their baseline lipoprotein(a) levels: groups I (< 30 mg/dL, n = 1,388), II (30–49 mg/dL, n = 263), and III (≥50 mg/dL, n = 257). Three-point major adverse cardiovascular events (a composite of nonfatal myocardial infarction, nonfatal stroke, and cardiac death) at 3 years were compared among the 3 groups. @*Results@#The patients were followed for 1094.0 (interquartile range, 1,033.8–1,095.0) days, during which a total of 326 (17.1%) three-point major adverse cardiovascular events occurred. Group III had higher rates of three-point major adverse cardiovascular events compared with Group I (23.0% vs. 15.7%; log-rank P = 0.009). In the subgroup analysis, group III had higher rates of three-point major adverse cardiovascular events compared with group I in patients with non-ST-segment elevation myocardial infarction (27.0% vs. 17.1%; log-rank P = 0.006), but not in patients with ST-segment elevation myocardial infarction (14.4% vs. 13.3%; logrank P = 0.597). However, in multivariable Cox time-to-event models, baseline lipoprotein(a) levels were not associated with an increased incidence of three-point major adverse cardiovascular events, regardless of the type of acute myocardial infarction. Sensitivity analyses in diverse subgroups showed similar findings to those of the main analysis. @*Conclusion@#Baseline lipoprotein(a) levels in Korean patients with acute myocardial infarction were not independently associated with increased major adverse cardiovascular events at 3 years.

Characteristics and Clinical Outcomes of Cancer Patients who Developed Constrictive Physiology After Pericardiocentesis

Background and objectives@#This study aimed to identify the characteristics and clinical outcomes of cancer patients who developed constrictive physiology (CP) after percutaneous pericardiocentesis. @*Methods@#One-hundred thirty-three cancer patients who underwent pericardiocentesis were divided into 2 groups according to follow-up echocardiography (CP vs. non-CP). The clinical history, imaging findings, and laboratory results, and overall survival were compared. @*Results@#CP developed in 49 (36.8%) patients after pericardiocentesis. The CP group had a more frequent history of radiation therapy. Pericardial enhancement and malignant masses abutting the pericardium were more frequently observed in the CP group. Fever and ST segment elevation were more frequent in the CP group, with higher C-reactive protein levels (6.6±4.3mg/dL vs. 3.3±2.5mg/dL, p<0.001). Pericardial fluid leukocytes counts were significantly higher, and positive cytology was more frequent in the CP group. In baseline echocardiography before pericardiocentesis, medial e′ velocity was significantly higher in the CP group (8.6±2.1cm/s vs. 6.5±2.3cm/s, p<0.001), and respirophasic ventricular septal shift, prominent expiratory hepatic venous flow reversal, pericardial adhesion, and loculated pericardial fluid were also more frequent. The risk of all-cause death was significantly high in the CP group (hazard ratio, 1.53; 95% confidence interval,1.10–2.13; p=0.005). @*Conclusions@#CP frequently develops after pericardiocentesis, and it is associated with poor survival in cancer patients. Several clinical signs, imaging, and laboratory findings suggestive of pericardial inflammation and/or direct malignant pericardial invasion are frequently observed and could be used as predictors of CP development.

Comparison of Prognosis According to the Use of Emergency Medical Services in Patients with ST-Segment Elevation Myocardial Infarction

Purpose@#This study aimed to compare long-term clinical outcomes according to the use of emergency medical services (EMS) in patients with ST-segment elevation myocardial infarction (STEMI) who arrived at the hospital within 12 hr of symptom onset. @*Materials and Methods@#A total of 13104 patients with acute myocardial infarction were enrolled in the Korea Acute Myocardial Infarction Registry–National Institutes of Health from October 2011 to December 2015. Of them, 2416 patients with STEMI who arrived at the hospital within 12 hr were divided into two groups: 987 patients in the EMS group and 1429 in the non-EMS group. Propensity score matching (PSM) was performed to reduce bias from confounding variables. After PSM, 796 patients in the EMS group and 796 patients in the non-EMS group were analyzed. The clinical outcomes during 3 years of clinical follow-up were compared between the two groups according to the use of EMS. @*Results@#The symptom-to-door time was significantly shorter in the EMS group than in the non-EMS group. The EMS group had more patients with high Killip class compared to the non-EMS group. The rates of all-cause death and major adverse cardiac events (MACE) were not significantly different between the two groups. After PSM, the rate of all-cause death and MACE were still not significantly different between the EMS and non-EMS groups. The predictors of mortality were high Killip class, renal dysfunction, old age, long door-to-balloon time, long symptom-to-door time, and heart failure. @*Conclusion@#EMS utilization was more frequent in high-risk patients. The use of EMS shortened the symptom-to-door time, but did not improve the prognosis in this cohort.

Prognostic Value of Baseline Neutrophilto-Lymphocyte Ratio Combined With Anemia in Patients With ST-Segment Elevation Myocardial Infarction: A Nationwide Prospective Cohort Study

Objective@#Data pertaining to the prognostic value of the combination of high neutrophilto-lymphocyte ratio (NLR) and anemia on admission in patients with ST-segment elevation myocardial infarction (STEMI) are limited. The objective of this study was to investigate the clinical value of baseline NLR in combination with anemia in predicting clinical outcomes after STEMI. @*Methods@#A total of 5,194 consecutive patients with STEMI within 12 hours of symptom onset from the Korea Acute Myocardial Infarction Registry-National Institute of Health database between 2011 and 2015 were categorized into 4 groups according to their NLR and hemoglobin levels: low NLR (<4) without anemia (n=2,722; reference group); high NLR (≥4) without anemia (n=1,527); low NLR with anemia (n=508); and high NLR with anemia (n=437). The co-primary outcomes were 180-day and 3-year all-cause mortality. @*Results@#Mortality rates significantly increased at the 3-year follow-up across the groups (3.3% vs. 5.4% vs. 16.5% vs. 21.7% for 180-day mortality and 5.3% vs. 9.0% vs. 23.8% vs. 33.4% for 3-year mortality; all p-trends <0.001). After adjusting for baseline covariates, the combination of high NLR and anemia was a significant predictor of 180-day mortality after STEMI with low NLR and no anemia as the reference (adjusted hazard ratio, 2.16; 95% confidence interval, 1.58–2.95; p<0.001). Similar findings were observed for the 3-year mortality. @*Conclusions@#This nationwide prospective cohort study showed that the combination of high NLR (≥4) and anemia is a strong predictor of all-cause mortality after STEMI.

Treatment delay and outcomes of ST-segment elevation myocardial infarction treated by primary percutaneous coronary intervention during the COVID-19 era in South Korea

Background/Aims@#Little is known about the clinical characteristics and treatment outcomes of ST-segment elevation myocardial infarction (STEMI) in Korea during the coronavirus disease 2019 (COVID-19) era. We aimed to evaluate the clinical characteristics and treatment outcomes of patients with STEMI in the COVID-19 era. @*Methods@#A total of 588 consecutive patients with STEMI who underwent primary percutaneous coronary intervention were included in this study. The patients were categorized into the COVID-19 (from January 20, 2020 to December 31, 2020) and control groups (from January 20, 2019 to December 31, 2019). @*Results@#The COVID-19 group showed pre-hospital and in-hospital delays than the control group. The control group underwent more thrombus aspiration and had a higher proportion of left main coronary artery diseases, while the COVID-19 group had a higher proportion of multivessel diseases with a marked increase in the number and total length of stents than the control group. As for the prescribed medications, the COVID-19 group was administered more beta-blockers, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, and statins than the control group. The clinical outcomes were comparable between the groups, except for higher incidences of atrioventricular block and temporary pacemaker implantation in the COVID-19 group. @*Conclusions@#Reperfusion after STEMI treatment during the COVID-19 period was delayed; therefore, efforts should be made to improve on reperfusion.

Predictors of recurrent acute myocardial infarction despite successful percutaneous coronary intervention

Background/Aims@#Recurrent acute myocardial infarction (AMI) is an adverse cardiac event in patients with a first AMI. The predictors of recurrent AMI after the first AMI in patients who underwent successful percutaneous coronary intervention (PCI) have not been elucidated. @*Methods@#We analyzed the data collected from 9,869 patients (63.2 ± 12.4 years, men:women = 7,446:2,423) who were enrolled in the Korea Acute Myocardial Infarction Registry-National Institute of Health between November 2011 and October 2015, had suffered their first AMI and had received successful PCI during the index hospitalization. Multivariable logistic regression analysis was performed to identify the independent predictors of recurrent AMI following the first AMI. @*Results@#The cumulative incidence of recurrent AMI after successful PCI was 3.6% (359/9,869). According to the multivariable logistic regression analysis, the significant predictive factors for recurrent AMI were diabetes mellitus, renal dysfunction, atypical chest pain, and multivessel disease. @*Conclusions@#In this Korean prospective cohort study, the independent predictors of recurrent AMI after successful PCI for the first AMI were diabetes mellitus, renal dysfunction, atypical chest pain, and multivessel disease.

The current status and outcomes of in-hospital P2Y12 receptor inhibitor switching in Korean patients with acute myocardial infarction

Background/Aims@#While switching strategies of P2Y12 receptor inhibitors (RIs) have sometimes been used in acute myocardial infarction (AMI) patients, the current status of in-hospital P2Y12RI switching remains unknown. @*Methods@#Overall, 8,476 AMI patients who underwent successful revascularization from Korea Acute Myocardial Infarction Registry-National Institute of Health (KAMIR-NIH) were divided according to in-hospital P2Y12RI strategies, and net adverse cardiovascular events (NACEs), defined as a composite of cardiac death, non-fatal myocardial infarction (MI), stroke, or thrombolysis in myocardial infarction (TIMI) major bleeding during hospitalization were compared. @*Results@#Patients with in-hospital P2Y12RI switching accounted for 16.5%, of which 867 patients were switched from clopidogrel to potent P2Y12RI (C-P) and 532 patients from potent P2Y12RI to clopidogrel (P-C). There were no differences in NACEs among the unchanged clopidogrel, the unchanged potent P2Y12RIs, and the P2Y12RI switching groups. However, compared to the unchanged clopidogrel group, the C-P group had a higher incidence of non-fatal MI, and the P-C group had a higher incidence of TIMI major bleeding. In clinical events of in-hospital P2Y12RI switching, 90.9% of non-fatal MI occurred during pre-switching clopidogrel administration, 60.7% of TIMI major bleeding was related to pre-switching P2Y12RIs, and 71.4% of TIMI major bleeding was related to potent P2Y12RIs. Only 21.6% of the P2Y12RI switching group switched to P2Y12RIs after a loading dose (LD); however, there were no differences in clinical events between patients with and without LD. @*Conclusions@#In-hospital P2Y12RI switching occurred occasionally, but had relatively similar clinical outcomes compared to unchanged P2Y12RIs in Korean AMI patients. Non-fatal MI and bleeding appeared to be mainly related to pre-switching P2Y12RIs.

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. @*Conclusions@#The outcomes of patients with Killip III–IV AMI admitted during off- and on-hours were similar.

Higher Long-Term Mortality in Patients with Non-ST-Elevation Myocardial Infarction than ST-Elevation Myocardial Infarction after Discharge

Purpose@#This study aimed to compare mortality rates after discharge between the patients with non-ST-elevation myocardial infarction (NSTEMI) and those with ST-elevation myocardial infarction (STEMI), and identify each mortality risk factors in these two types of myocardial infarction. @*Materials and Methods@#Between 2011 and 2015, 13105 consecutive patients were enrolled in the Korea Acute Myocardial Infarction-National Institute of Health registry (KAMIR-NIH); 12271 patients with acute myocardial infarction met the inclusion criteria and were further stratified into the STEMI (n=5828) and NSTEMI (n=6443) groups. The occurrence of mortality and cardiac mortality at 3 years were compared between groups, and the factors associated with mortality for NSTEMI and STEMI were evaluated. @*Results@#The comparison between these two groups and long-term follow-up outcomes showed that the cumulative rates of allcause and cardiac mortality were higher in the NSTEMI group than in the STEMI group [all-cause mortality: 10.9% vs. 5.8%; hazards ratio (HR), 0.464; 95% confidence interval (CI), 0.359–0.600, p100 beats/min), no PCI, and low hemoglobin level were identified as the risk factors for 3-year mortality. @*Conclusion@#The NSTEMI group had higher mortality compared to the STEMI group during the 3-year clinical follow-up after discharge. Low LVEF and no PCI were the main risk factors for mortality in the NSTEMI group. In contrast, old age and renal dysfunction were the risk factors for long-term mortality in the STEMI group.

Preclinical Evaluation of a Novel Polymer-free Everolimus-eluting Stent in a Mid-term Porcine Coronary Restenosis Model

Background@#Titanium dioxide films exhibit good biocompatibility and may be effective as drug-binding matrices for drug-eluting stents. We conducted a mid-term evaluation of a novel polymer-free everolimus-eluting stent using nitrogen-doped titanium dioxide film deposition (TIGEREVOLUTION® ) in comparison with a commercial durable polymer everolimus-eluting stent (XIENCE Alpine® ) in a porcine coronary restenosis model. @*Methods@#Twenty-eight coronary arteries from 14 mini-pigs were randomly allocated to TIGEREVOLUTION® stent and XIENCE Alpine® stent groups. The stents were implanted in the coronary artery at a 1.1–1.2:1 stent-to-artery ratio. Eleven stented coronary arteries in each group were finally analyzed using coronary angiography, optical coherence tomography, and histopathologic evaluation 6 months after stenting. @*Results@#Quantitative coronary analysis showed no significant differences in the preprocedural, post-procedural, and 6-month lumen diameters between the groups. In the volumetric analysis of optical coherence tomography at 6 months, no significant differences were observed in stent volume, lumen volume, and percent area stenosis between the groups. There were no significant differences in injury score, inflammation score, or fibrin score between the groups, although the fibrin score was zero in the TIGEREVOLUTION® stent group (0 vs. 0.07 ± 0.11, P = 0.180). @*Conclusion@#Preclinical evaluation, including optical coherence tomographic findings 6 months after stenting, demonstrated that the TIGEREVOLUTION® stent exhibited efficacy and safety comparable with the XIENCE Alpine® stent, supporting the need for further clinical studies on the TIGEREVOLUTION® stent.

2021 Korean Society of Myocardial Infarction Expert Consensus Document on Revascularization for Acute Myocardial Infarction

Acute myocardial infarction (AMI) is a fatal manifestation of ischemic heart disease and remains a major public health concern worldwide despite advances in its diagnosis and management. The characteristics of patients with AMI, as well as its disease patterns,have gradually changed over time in Korea, and the outcomes of revascularization have improved dramatically. Several characteristics associated with the revascularization of Korean patients differ from those of patients in other countries. The sophisticated state of AMI revascularization in Korea has led to the need for a Korean expert consensus. The Task Force on Expert Consensus Document of the Korean Society of Myocardial Infarction has comprehensively reviewed the outcomes of large clinical trials and current practical guidelines, as well as studies on Korean patients with AMI. Based on these comprehensive reviews, the members of the task force summarize the major guidelines and recent publications, and propose an expert consensus for revascularization in patients with AMI.