Kenji Inoue

Acute coronary syndrome (ACS) remains one of the leading causes of cardiovascular morbidity and mortality. Recent advances in high-sensitivity cardiac troponin assays, multimodal imaging, and antithrombotic therapies have introduced more individualized risk assessment and management. This review highlights a precision-oriented diagnostic pathway, which integrates the 0/1-hour algorithm with imaging modalities for the comprehensive evaluation of culprit and non-culprit lesions. Revascularization strategies are advancing, with imaging-guided percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG), enabling more tailored approaches for complex diseases. Meanwhile, mechanical circulatory support offers potential benefits for cardiogenic shock; nevertheless, there are uncertainties regarding optimal timing and patient selection. Long-term antithrombotic therapy is becoming increasingly optimized. Recent strategies have focused on reducing the duration of dual antiplatelet therapy (DAPT) and exploring de-escalation approaches such as P2Y12 inhibitor monotherapy. Secondary prevention extends beyond lipid-lowering therapies and includes metabolic and anti-inflammatory interventions. Collectively, these advancements indicate a shift toward truly personalized care for ACS, aiming to improve outcomes by transitioning away from a one-size-fits-all approach.

Background Rapid triage of patients presenting with chest pain is essential for early diagnosis and safe disposition. The European Society of Cardiology (ESC) 0/1-hour hs-cTn algorithm has shown promising performance in Western cohorts, but evidence supporting its implementation in diverse Asian emergency department (ED) settings remains limited. Therefore, we evaluated the safety and clinical utility of the ESC 0/1-hour algorithm for chest pain triage across multiple Asian EDs. Methods This was a prospective, stepped-wedge, cluster-randomised trial conducted across 12 hospitals in five Asian countries, enrolling 3869 patients with suspected acute coronary syndrome without ST elevation (NSTE-ACS). Usual care involved troponin testing without standardised timing, whereas the 0/1-hour protocol followed ESC recommendations using high-sensitivity cardiac troponin T testing at baseline and 1 hour. The primary endpoint was 30-day major adverse cardiac events (MACE), including cardiovascular death, myocardial infarction (MI) and unplanned revascularisation. Non-inferiority was assessed using a one-sided 95% CI with a margin of 1.5%. Results Of 3869 patients (2059 usual care; 1810 0/1-hour care), MACE occurred in 1.7% of usual care patients and 1.4% in the 0/1-hour care (upper one-sided 95% CI –0.3%), confirming non-inferiority. ED discharge rates were significantly higher with the 0/1-hour algorithm (60% vs 35%, pConclusion The ESC 0/1-hour algorithm is safe and effective for rapid triage of chest pain in Asian EDs. These findings provide external validation of the 0/1-hour algorithm and support broader global implementation. Trial registration number UMIN000042461.

Background: Patients with atrial fibrillation (AF) often present with symptoms similar to acute coronary syndrome (ACS), including chest pain and elevated levels of high-sensitivity cardiac troponin (hs-cTn). The 0/1-hour algorithm using hs-cTn is a rapid diagnostic tool endorsed by the European Society of Cardiology to rule out myocardial infarction (MI). However, because its effectiveness in patients with AF remains unclear, in this study we assessed the diagnostic accuracy of the 0/1-hour algorithm in patients with and without AF presenting with chest pain in the emergency department.Methods and Results: We conducted a secondary analysis of the DROP-ACS cohort, including 1,333 patients from Japan and Taiwan, with AF in 10.3% of cases. We examined the algorithm’s negative predictive value (NPV), sensitivity, positive predictive value (PPV), and specificity for ruling MI in or out. Patients with AF were more frequently placed in the observe group (54% vs. 34.9%, P<0.05) and less often in the rule-out group (24.1% vs. 44.6%, P<0.05). The NPV and sensitivity for ruling out MI were 100%, while the PPV and specificity were lower in patients with AF (60% and 89.7%, respectively).Conclusions: The 0/1-hour algorithm effectively ruled out MI in patients with AF, with high safety and accuracy. However, patients with AF are more likely to be stratified into the observe group, requiring further examination for final diagnosis.

Acute coronary syndrome (ACS) is associated with high mortality rates. Although the goal was to achieve a missed diagnosis rate of 2%. Chest pain diagnosis has remained unchanged over the years and is based on medical interviews and electrocardiograms (ECG), with biomarkers playing complementary roles. We aimed to summarize the key points of medical interviews, ECG clinics, use of biomarkers, and clinical scores, identify problems, and provide directions for future research. Medical interviews should focus on the character and location of chest pain (is it accompanied by radiating pain?) and the duration, induction, and ameliorating factors. An ECG should be recorded within 10 minutes of the presentation. The serial performance of an ECG is recommended for emergency department (ED) evaluation of suspected ACS. Characteristic ECG traces, such as Wellens syndrome and De Winter T-waves, should be understood. Therefore, troponin levels in all patients with suspected ischemic heart disease should be examined using a highly sensitive assay system. Depending on the ED facility, the patient should be risk stratified by serial measurements of cardiac troponin levels (re-testing at one hour would be preferred) to determine the appropriate time to perform an invasive strategy for a definitive diagnosis. The diagnostics should be based on Bayes’ theorem; however, care should be taken to avoid the influence of heuristic bias.

Takotsubo cardiomyopathy (TCM) leads to serious left ventricular outflow tract (LVOT) obstruction with cardiogenic shock in 6%–20% of cases. The onset of LVOT obstruction, coupled with mitral regurgitation resulting from systolic anterior motion of mitral valve leaflets, can lead to haemodynamic instability in addition to severely impaired systolic function. We describe three patients who experienced chest discomfort following emotional stress. These patients displayed pronounced abnormalities on ECGs, insignificant obstructive coronary disease and haemodynamic instability due to LVOT obstruction. The infusion of landiolol, a short-acting beta blocker, was effective in releasing the gradient. Dynamic outflow obstruction is the major predictor of haemodynamic collapse. We suggested that an early identification of this complication in hypotensive patients with suspected TCM could be of utmost importance to optimise the therapeutic approach in the acute setting.

Background: This study investigated the economic impact of the European Society of Cardiology (ESC) clinical practice guideline recommendation of using the 0-h/1-h rule-out and rule-in algorithm with high-sensitivity cardiac troponin assays (0/1-h algorithm) to triage patients presenting with chest pain.Methods and Results: This post hoc cost-effectiveness evaluation (DROP-ACS; UMIN000030668) used deidentified electronic medical records from health insurance claims from 2 diagnostic centers in Japan. A cost-effectiveness analysis was conducted with 472 patients with care provided following the 0/1-h algorithm (Hospital A) and 427 patients following point-of-care testing (Hospital B). The clinical outcome of interest was all-cause mortality or subsequent myocardial infarction within 30 days of the index presentation. The sensitivity and specificity for the clinical outcome were 100% (95% confidence interval [CI] 91.1–100%) and 95.0% (95% CI 94.3–95.0%), respectively, in Hospital A and 92.9% (95% CI 69.6–98.7%) and 89.8% (95% CI 89.0–90.0%), respectively, in Hospital B. If the diagnostic accuracy of the 0/1-h algorithm was implemented in Hospital B, it is expected that the number of urgent (<24-h) coronary angiograms would decrease by 50%. Incorporating this assumption, implementing the 0/1-h algorithm could potentially reduce medical costs by JPY4,033,874 (95% CI JPY3,440,346–4,627,402) in Hospital B (JPY9,447 per patient; 95% CI JPY 8,057–10,837 per patient).Conclusions: The ESC 0/1-h algorithm was efficient for risk stratification and for reducing medical costs.

The European Society of Cardiology recommends the 0/1-hour algorithm for risk stratification of patients with suspected non-ST-elevation myocardial infarction as class I, level B; however, there are few reports on the long-term prognosis, resulting in a rule-out group. We aimed to determine whether implementation of the 0-hour/1-hour algorithm is safe and effective in emergency department (ED) patients with possible acute coronary syndrome (ACS) through a 1-year follow-up period. Our study analyzed the 1-year follow-up data from a prospective pre-post study of 1106 ED patients with possible ACS from 4 hospitals in Japan and Taiwan. Patients were 18 years or older. Accrual occurred for 1 year after implementing the 0-1-hour algorithm from November 2014 to December 2018. Overall, 520 patients were stratified into the rule-out group. Major advanced cardiovascular events (all-cause death, acute myocardial infarction [AMI], stroke, unstable angina, and revascularization) at 1-year were determined using data from health records and phone calls. The 0-1-hour algorithm stratified 47.0% of patients in the rule-out group. Over the 1-year follow-up period (follow-up rate = 86.9%), cardiovascular death and subsequent AMI did not occur in the rule-out group. Among the 27 patients who underwent the procedure within 30 days post-index visit, 3 patients (0.7%) had a stroke, 6 patients (1.3%) died of non-cardiovascular cause, and 30 patients (6.7%) underwent coronary revascularization within 1 year. At the 1-year follow-up, implementation of the 0-hour/1-hour algorithm was associated with very low rates of adverse event among patients in the rule-out group.