Background and Objectives: Cigarette smoking is a major risk factor for atherosclerosis.Nicotine, a crucial constituent of tobacco, contributes to atherosclerosis development and progression. However, evidence of the association between nicotine and neointima formation is limited. We aimed to evaluate whether nicotine enhances neointimal hyperplasia in the native epicardial coronary arteries of pigs after percutaneous coronary intervention (PCI) with drug-eluting stents (DES). Methods: After coronary angiography (CAG) and quantitative coronary angiography (QCA), we implanted 20 DES into 20 pigs allocated to 2 groups: no-nicotine (n=10) and nicotine (n=10) groups. Post-PCI CAG and QCA were performed immediately. Follow-up CAG, QCA, optical coherence tomography (OCT), and histopathological analyses were performed 2 months post-PCI. Results: Despite intergroup similarities in the baseline QCA findings, OCT analysis showed that the nicotine group had a smaller mean stent and lumen areas, a larger mean neointimal area, greater percent area stenosis, and higher peri-strut fibrin and inflammation scores than the no-nicotine group. In immunofluorescence analysis, the nicotine group displayed higher expression of CD68 and α-smooth muscle actin but lower CD31 expression than the no-nicotine group. Conclusions Nicotine inhibited re-endothelialization and promoted inflammation and NIH after PCI with DES in a porcine model.

Background and Objectives: Cigarette smoking is a major risk factor for atherosclerosis.Nicotine, a crucial constituent of tobacco, contributes to atherosclerosis development and progression. However, evidence of the association between nicotine and neointima formation is limited. We aimed to evaluate whether nicotine enhances neointimal hyperplasia in the native epicardial coronary arteries of pigs after percutaneous coronary intervention (PCI) with drug-eluting stents (DES). Methods: After coronary angiography (CAG) and quantitative coronary angiography (QCA), we implanted 20 DES into 20 pigs allocated to 2 groups: no-nicotine (n=10) and nicotine (n=10) groups. Post-PCI CAG and QCA were performed immediately. Follow-up CAG, QCA, optical coherence tomography (OCT), and histopathological analyses were performed 2 months post-PCI. Results: Despite intergroup similarities in the baseline QCA findings, OCT analysis showed that the nicotine group had a smaller mean stent and lumen areas, a larger mean neointimal area, greater percent area stenosis, and higher peri-strut fibrin and inflammation scores than the no-nicotine group. In immunofluorescence analysis, the nicotine group displayed higher expression of CD68 and α-smooth muscle actin but lower CD31 expression than the no-nicotine group. Conclusions Nicotine inhibited re-endothelialization and promoted inflammation and NIH after PCI with DES in a porcine model.

Background and Objectives: Cigarette smoking is a major risk factor for atherosclerosis.Nicotine, a crucial constituent of tobacco, contributes to atherosclerosis development and progression. However, evidence of the association between nicotine and neointima formation is limited. We aimed to evaluate whether nicotine enhances neointimal hyperplasia in the native epicardial coronary arteries of pigs after percutaneous coronary intervention (PCI) with drug-eluting stents (DES). Methods: After coronary angiography (CAG) and quantitative coronary angiography (QCA), we implanted 20 DES into 20 pigs allocated to 2 groups: no-nicotine (n=10) and nicotine (n=10) groups. Post-PCI CAG and QCA were performed immediately. Follow-up CAG, QCA, optical coherence tomography (OCT), and histopathological analyses were performed 2 months post-PCI. Results: Despite intergroup similarities in the baseline QCA findings, OCT analysis showed that the nicotine group had a smaller mean stent and lumen areas, a larger mean neointimal area, greater percent area stenosis, and higher peri-strut fibrin and inflammation scores than the no-nicotine group. In immunofluorescence analysis, the nicotine group displayed higher expression of CD68 and α-smooth muscle actin but lower CD31 expression than the no-nicotine group. Conclusions Nicotine inhibited re-endothelialization and promoted inflammation and NIH after PCI with DES in a porcine model.

Background and Objectives: Cigarette smoking is a major risk factor for atherosclerosis.Nicotine, a crucial constituent of tobacco, contributes to atherosclerosis development and progression. However, evidence of the association between nicotine and neointima formation is limited. We aimed to evaluate whether nicotine enhances neointimal hyperplasia in the native epicardial coronary arteries of pigs after percutaneous coronary intervention (PCI) with drug-eluting stents (DES). Methods: After coronary angiography (CAG) and quantitative coronary angiography (QCA), we implanted 20 DES into 20 pigs allocated to 2 groups: no-nicotine (n=10) and nicotine (n=10) groups. Post-PCI CAG and QCA were performed immediately. Follow-up CAG, QCA, optical coherence tomography (OCT), and histopathological analyses were performed 2 months post-PCI. Results: Despite intergroup similarities in the baseline QCA findings, OCT analysis showed that the nicotine group had a smaller mean stent and lumen areas, a larger mean neointimal area, greater percent area stenosis, and higher peri-strut fibrin and inflammation scores than the no-nicotine group. In immunofluorescence analysis, the nicotine group displayed higher expression of CD68 and α-smooth muscle actin but lower CD31 expression than the no-nicotine group. Conclusions Nicotine inhibited re-endothelialization and promoted inflammation and NIH after PCI with DES in a porcine model.

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.

Background and Objectives: Real-world evidence on the relationship between delayed hospitalization and outcomes in myocardial infarction with nonobstructive coronary arteries (MINOCA) is lacking. Hence, we aimed to evaluate the clinical characteristics of patients with MINOCA and the 2-year mortality outcomes in this patient population according to the symptom-to-door time (SDT). Methods: Overall, 861 patients with MINOCA from 2 Korean nationwide observational registries (2011–2020) were included and categorized as early or late presenters. Late presentation was defined as SDT ≥12 hours in patients with ST-segment elevation myocardial infarction (STEMI) and SDT ≥24 hours in patients with non-STEMI. The primary outcome was 2-year all-cause mortality. Propensity score matching (PSM) and age-sex adjusted analysis were used to determine whether late presentation independently affected mortality.Multivariate logistic regression analysis was used to examine the independent factors correlated with late presentation. Results: In unadjusted data, late presenters had a notably higher risk of 2-year all-cause mortality than early presenters (hazard ratio [HR], 2.44; 95% confidence interval [CI], 1.47–4.08). This trend persisted in age-sex adjusted analysis (adjusted HR, 2.29; 95% CI, 1.36–3.84) and PSM-adjusted analysis (adjusted HR, 2.18; 95% CI, 1.05–4.53). The positive independent factors for late presentation included female sex, no emergency medical service use and high creatinine level, whereas the negative independent factor was a dyslipidemia. Conclusions Late presentation is associated with higher mortality in patients with MINOCA.Multidisciplinary efforts are needed to reduce pre-hospital delay, thereby improving the clinical outcomes in these patients.

Background/Aims: Drug-eluting balloons (DEBs) represent a novel therapeutic approach for patients with small coronary artery disease. However, further studies are needed to compare the clinical efficacy of DEBs versus drug-eluting stents (DESs). Methods: In total, 492 patients (age, 67.9 ± 11.0 years; 339 men) with small coronary artery lesions (diameter < 2.75 mm) were randomly assigned to group I (DEB) (n = 104; age, 67.2 ± 10.7 years; 83 men) and group II (DES) (n = 388; age, 68.0 ± 11.1 years; 254 men). For inverse probability of treatment weighting (IPTW) analysis, the study population was stratified into groups I (n = 269) and II (n = 280). We compared the incidences of major adverse cardiac events (MACE) between the two groups during 12 months of clinical follow-up. Results: Group I had shorter device lengths (22.4 ± 5.8 mm) compared with group II (27.4 ± 9.3 mm; p < 0.001). Additionally, devices in group I were smaller in diameter (2.4 ± 0.1 mm) compared with those in group II (2.6 ± 0.1 mm; p < 0.001). Left ventricular ejection fraction (LVEF) was lower in group I (53.8% ± 12.6%) than in group II (58.6% ± 11.9%; p < 0.001). After IPTW, no significant differences in LVEF were observed between groups I and II. During 12 months of follow-up, the incidence of total MACE did not differ between the two groups. Conclusions No significant differences were observed in clinical efficacy between DEB and DES for the treatment of small coronary artery disease. Therefore, DEB can be considered a viable alternative to DES in patients with small coronary artery disease.

Background and Objectives: Real-world evidence on the relationship between delayed hospitalization and outcomes in myocardial infarction with nonobstructive coronary arteries (MINOCA) is lacking. Hence, we aimed to evaluate the clinical characteristics of patients with MINOCA and the 2-year mortality outcomes in this patient population according to the symptom-to-door time (SDT). Methods: Overall, 861 patients with MINOCA from 2 Korean nationwide observational registries (2011–2020) were included and categorized as early or late presenters. Late presentation was defined as SDT ≥12 hours in patients with ST-segment elevation myocardial infarction (STEMI) and SDT ≥24 hours in patients with non-STEMI. The primary outcome was 2-year all-cause mortality. Propensity score matching (PSM) and age-sex adjusted analysis were used to determine whether late presentation independently affected mortality.Multivariate logistic regression analysis was used to examine the independent factors correlated with late presentation. Results: In unadjusted data, late presenters had a notably higher risk of 2-year all-cause mortality than early presenters (hazard ratio [HR], 2.44; 95% confidence interval [CI], 1.47–4.08). This trend persisted in age-sex adjusted analysis (adjusted HR, 2.29; 95% CI, 1.36–3.84) and PSM-adjusted analysis (adjusted HR, 2.18; 95% CI, 1.05–4.53). The positive independent factors for late presentation included female sex, no emergency medical service use and high creatinine level, whereas the negative independent factor was a dyslipidemia. Conclusions Late presentation is associated with higher mortality in patients with MINOCA.Multidisciplinary efforts are needed to reduce pre-hospital delay, thereby improving the clinical outcomes in these patients.

Background/Aims: Drug-eluting balloons (DEBs) represent a novel therapeutic approach for patients with small coronary artery disease. However, further studies are needed to compare the clinical efficacy of DEBs versus drug-eluting stents (DESs). Methods: In total, 492 patients (age, 67.9 ± 11.0 years; 339 men) with small coronary artery lesions (diameter < 2.75 mm) were randomly assigned to group I (DEB) (n = 104; age, 67.2 ± 10.7 years; 83 men) and group II (DES) (n = 388; age, 68.0 ± 11.1 years; 254 men). For inverse probability of treatment weighting (IPTW) analysis, the study population was stratified into groups I (n = 269) and II (n = 280). We compared the incidences of major adverse cardiac events (MACE) between the two groups during 12 months of clinical follow-up. Results: Group I had shorter device lengths (22.4 ± 5.8 mm) compared with group II (27.4 ± 9.3 mm; p < 0.001). Additionally, devices in group I were smaller in diameter (2.4 ± 0.1 mm) compared with those in group II (2.6 ± 0.1 mm; p < 0.001). Left ventricular ejection fraction (LVEF) was lower in group I (53.8% ± 12.6%) than in group II (58.6% ± 11.9%; p < 0.001). After IPTW, no significant differences in LVEF were observed between groups I and II. During 12 months of follow-up, the incidence of total MACE did not differ between the two groups. Conclusions No significant differences were observed in clinical efficacy between DEB and DES for the treatment of small coronary artery disease. Therefore, DEB can be considered a viable alternative to DES in patients with small coronary artery disease.

Colorectal cancer is the third most common cancer in Korea and the third leading cause of death from cancer. Treatment outcomes for colon cancer are steadily improving due to national health screening programs with advances in diagnostic methods, surgical techniques, and therapeutic agents.. The Korea Colon Cancer Multidisciplinary (KCCM) Committee intends to provide professionals who treat colon cancer with the most up-to-date, evidence-based practice guidelines to improve outcomes and help them make decisions that reflect their patients’ values and preferences. These guidelines have been established by consensus reached by the KCCM Guideline Committee based on a systematic literature review and evidence synthesis and by considering the national health insurance system in real clinical practice settings. Each recommendation is presented with a recommendation strength and level of evidence based on the consensus of the committee.