Atherothrombotic events are influenced by systemic hypercoagulability and fibrinolytic activity. The present study evaluated thrombogenicity indices and their prognostic implications according to disease acuity. From the consecutive patients undergoing percutaneous coronary intervention (PCI), those with thrombogenicity indices (n = 2705) were grouped according to disease acuity [acute myocardial infarction (AMI) vs. non-AMI]. Thrombogenicity indices were measured by thromboelastography (TEG). Blood samples for TEG were obtained immediately after insertion of the PCI sheath, and TEG tracing was performed within 4 h post-sampling. Major adverse cardiovascular events (MACE, a composite of cardiovascular death, non-fatal myocardial infarction, and non-fatal stroke) were evaluated for up to 4 years. Compared with non-AMI patients, AMI patients had higher platelet-fibrin clot strength [maximal amplitude (MA): 66.5 ± 7.8 vs. 65.3 ± 7.2 mm, P < 0.001] and lower fibrinolytic activity [clot lysis at 30 min (LY₃₀): 0.9 ± 1.8% vs. 1.1 ± 1.9%, P < 0.001]. Index AMI presentation was associated with MA [per one-mm increase: odds ratio (OR): 1.024; 95% confidence interval (CI): 1.013–1.036; P < 0.001] and LY₃₀ (per one% increase: OR: 0.934; 95% CI: 0.893–0.978; P = 0.004). The presence of high platelet-fibrin clot strength (MA ≥68 mm) and low fibrinolytic activity (LY₃₀ < 0.2%) was synergistically associated with MACE occurrence. In the multivariable analysis, the combined phenotype of ‘MA ≥ 68 mm’ and ‘LY₃₀ < 0.2%’ was a major predictor of post-PCI MACE in the AMI group [adjusted hazard ratio (HR): 1.744; 95% CI: 1.135–2.679; P = 0.011], but not in the non-AMI group (adjusted HR: 1.031; 95% CI: 0.499–2.129; P = 0.935). AMI occurrence is significantly associated with hypercoagulability and impaired fibrinolysis. Their combined phenotype increases the risk of post-PCI atherothrombotic event only in AMI patients. These observations may support individualized therapy that targets thrombogenicity for better outcomes in patients with AMI. Gyeongsang National University Hospital (G-NUH) Registry, NCT04650529. The association between thrombogenicity and AMI occurrence, and their prognostic implications for long-term cardiovascular outcomes were investigated. Abbreviations: AMI, acute myocardial infarction; HR, hazard ratio; LY30, percentage of the clot that has lysed 30 minutes after the time of maximum amplitude; MA, maximum amplitude; MACE, major adverse cardiovascular events; OR, odds ratio; PCI, percutaneous coronary intervention; TEG, thromboelastography.

Background and Aims: Platelet-fibrin clot strength (PFCS) is linked to major adverse cardiovascular event (MACE) risk. However, the association between PFCS and platelet reactivity and their prognostic implication remains uncertain in patients undergoing percutaneous coronary intervention (PCI). Methods: In PCI-treated patients (n = 2512) from registry data from January 2010 to November 2018 in South Korea, PFCS using thromboelastography and platelet reactivity using VerifyNow were measured. High PFCS (PFCSHigh) was defined as thromboelastography maximal amplitude ≥ 68 mm, and high platelet reactivity (HPR) was defined as >208 P2Y12 reaction units. Patients were stratified into four groups according to maximal amplitude and P2Y12 reaction unit levels: (i) normal platelet reactivity (NPR)-PFCSNormal (31.8%), (ii) HPR-PFCSNormal (29.0%), (iii) NPR-PFCSHigh (18.1%), and (iv) HPR-PFCSHigh (21.1%). Major adverse cardiovascular event (all-cause death, myocardial infarction, or stroke) and major bleeding were followed up to 4 years. Results: High platelet reactivity and PFCSHigh showed an additive effect for clinical outcomes (log-rank test, P < .001). Individuals with NPR-PFCSNormal, NPR-PFCSHigh, HPR-PFCSNormal, and HPR-PFCSHigh demonstrated MACE incidences of 7.5%, 12.6%, 13.4%, and 19.3%, respectively. The HPR-PFCSHigh group showed significantly higher risks of MACE compared with the NPR-PFCSNormal group [adjusted hazard ratio (HRadj) 1.89; 95% confidence interval (CI) 1.23–2.91; P = .004] and the HPR-PFCSNormal group (HRadj 1.60; 95% CI 1.12–2.27; P = .009). Similar results were observed for all-cause death. Compared with HPR-PFCSNormal phenotype, NPR-PFCSNormal phenotype was associated with a higher risk of major bleeding (HRadj 3.12; 95% CI 1.30–7.69; P = .010). Conclusions: In PCI patients, PFCS and platelet reactivity demonstrated important relationships in predicting clinical prognosis. Their combined assessment may enhance post-PCI risk stratification for personalized antithrombotic therapy.

A 48-year-old female patient underwent a heart transplantation for acute fulminant myocarditis, following heterologous vaccination with the ChAdOx1 nCoV-19 and Pfizer-BioNTech COVID-19. She had no history of severe acute respiratory syndrome coronavirus-2 infection. She did not exhibit clinical signs or have laboratory findings of concomitant infection before or after vaccination. Heart transplantation was performed because her heart failed to recover with venoarterial extracorporeal oxygenation support. Organ autopsy revealed giant cell myocarditis, possibly related to the vaccines. Clinicians may have to consider the possibility of the development of giant cell myocarditis, especially in patients with rapidly deteriorating cardiac function and myocarditis symptoms after COVID-19 vaccination.

Objectives: To evaluate the effect of clopidogrel vs. aspirin monotherapy on vascular function and hemostatic measurement. Background: Monotherapy with P2Y₁₂ receptor inhibitor vs. aspirin can be a useful alterative to optimize clinical efficacy and safety in high-risk patients with coronary artery disease (CAD). Methods: We performed a randomized, open-label, two-period crossover study in stented patients receiving at least 6-month of dual antiplatelet therapy (DAPT). Thirty CAD patients with moderate-to-high ischemic risk were randomly assigned to receive either 75 mg of clopidogrel or 100 mg of aspirin daily for 4 weeks, and were crossed over to the other strategy for 4 weeks. Vascular function was evaluated with reactive hyperemia-peripheral arterial tonometry (RH-PAT) and brachial-ankle pulse wave velocity (baPWV). Hemostatic profiles were measured with VerifyNow and thromboelastography (TEG). The primary endpoint was the reactive hyperemia index (RHI) during clopidogrel or aspirin monotherapy. Results: Clopidogrel vs. aspirin monotherapy was associated with better endothelial function (RHI: 2.11 ± 0.77% vs. 1.87 ± 0.72%, p = 0.045), lower platelet reactivity (130 ± 64 vs. 214 ± 50 P2Y12 reaction unit [PRU], p < 0.001) and prolonged reaction time (TEG R: 5.5 ± 1.2 vs. 5.1 ± 1.1 min, p = 0.037). In multivariate analysis, normal endothelial function (RHI ≥ 2.1) was significantly associated with clot kinetics (TEG angle ≤ 68 degree) and ‘PRU ≤ 132’. ‘PRU ≤ 132’ was achieved in 46.2% vs. 3.8% during clopidogrel administration vs. aspirin monotherapy (odds ratio 21.4, 95% confidence interval 2.7 to 170.1, p < 0.001). Conclusions: In CAD patients, clopidogrel vs. aspirin monotherapy was associated with better endothelial function, greater platelet inhibition and lower coagulation activity, suggesting pleiotropic effects of clopidogrel on endothelial function and hemostatic profiles.

Objective: Strokes related to tandem occlusions of the internal carotid artery (ICA) and a major intracranial artery are associated with poor clinical outcome. We evaluated the clinical efficacy of endovascular approach for the management of these lesions. We also compared the clinical outcomes regarding the type of cervical ICA lesions; complete occlusion v s severe stenosis. Methods: We retrospectively reviewed 42 patients with acute ischemic stroke who underwent endovascular treatment for tandem lesions between January 2011 and April 2017. After dividing the patients into two groups according to lesion type of the proximal cervical ICA (complete occlusion and severe stenosis), we analyzed demographic data, angiographic findings and clinical outcomes. A modified Rankin Scale score ≤2 was defined as a favorable clinical outcome. Results: Of 42 patients, 27 patients (64.3%) had complete occlusion of the cervical ICA, and the remaining 15 had high-grade stenosis. Successful stenting was performed in all patients with favorable clinical outcomes (27/42, 64.3%). Successful reperfusion score (thrombolysis in cerebral infarction ≥2b) was 78.6%; occlusion group (18/27, 66.7%) vs stenosis group (15/15, 100%) of cases. Mean modified Rankin Scale score at 90 days was 2.36 ± 1.83. The rate of favorable clinical outcome was higher in stenosis group (11/15, 73.3%) than that of occlusion group (16/27, 59.3%) with no statistically significant difference (p = 0.506). Conclusion: Acute endovascular treatment of carotid artery tandem lesions is a technically feasible and clinically effective intervention regardless of the lesion type in proximal cervical ICA. Advances in knowledge: Our study supports the results of previous studies in which endovascular therapy has a favorable clinical outcome in carotid artery tandem occlusion.

Background and Aims: The optimal timing of complete revascularization in patients with ST-segment elevation myocardial infarction (STEMI) and multivessel disease complicated by heart failure remains uncertain. Methods: The OPTION-STEMI (Optimal Timing of Fractional Flow Reserve-Guided Complete Revascularization for Non-Infarct-Related Artery in ST-segment Elevation Myocardial Infarction with Multivessel Disease) trial compared immediate vs staged complete revascularization during the index admission in patients with STEMI and multivessel disease. In the OPTION-STEMI trial, immediate complete revascularization was not found to be non-inferior for the primary endpoint compared with staged complete revascularization. Pre-specified subgroup analysis was performed according to heart failure at admission, defined as Killip class II or III. The primary endpoint was a composite of death from any cause, non-fatal myocardial infarction, or any unplanned revascularization at 1 year. Results: Among 994 randomized patients, 329 (33.1%) had heart failure at admission. These patients had a higher risk of primary endpoint than those without heart failure (18.2% vs 8.7%; adjusted HR 1.63; 95% CI 1.11–2.40; P = .013). At 1 year, immediate complete revascularization was associated with a higher incidence of the primary endpoint than staged complete revascularization in patients with heart failure (22.8% vs 13.3%; HR 1.79; 95% CI 1.05–3.04), but not in those without heart failure (8.0% vs 9.5%; HR 0.84; 95% CI .50–1.40). A significant interaction was observed between heart failure status and randomized strategy (P = .043). Conclusions: In the OPTION-STEMI trial, among patients with STEMI and multi-vessel disease who were not in cardiogenic shock, immediate complete revascularization was not non-inferior compared with staged complete revascularization. However, subgroup analysis suggests that the worse outcomes with immediate complete revascularization may be limited to patients with heart failure at admission. Further studies are required to demonstrate the non-inferiority of immediate complete revascularization compared with staged complete revascularization in patients without heart failure.