Impact of prior coronary revascularisation on clinical presentation and one-year outcomes in acute coronary syndrome

Background Patients presenting with acute coronary syndrome (ACS) after prior coronary revascularization have traditionally been regarded as a high-risk population with poorer outcomes than those experiencing their first ACS event. Although many clinical trials have described this adverse prognosis, contemporary guideline-directed medical therapy (GDMT) may attenuate the clinical risk. This study evaluated current clinical characteristics and long-term outcomes of ACS patients with previous coronary revascularization in a real-world setting. Methods Our institution is the only hospital in the region providing 24-hour emergency percutaneous coronary intervention (PCI), resulting in a high concentration of ACS referrals, including those with prior interventions. We retrospectively reviewed 502 consecutive ACS patients who underwent emergency PCI from January 2021 to July 2024. Patients were categorized into Prior Revascularization and First-time Revascularization groups. Baseline demographics, cardiovascular risk profiles, medication use, angiographic findings, and in-hospital outcomes were compared. The primary endpoint was 1-year major adverse cardiovascular events (MACE), defined as a composite of all-cause death, myocardial infarction, and target lesion revascularization. Results Among the 502 patients, 93 (18.5%) had prior revascularization, whereas 409 (81.5%) presented with their first ACS requiring PCI. Patients with prior revascularization were older and had higher rates of diabetes, chronic kidney disease, and peripheral artery disease. They more frequently received antiplatelet therapy, statins, and beta-blockers, resulting in lower LDL-cholesterol levels at presentation. The incidence of ST-segment elevation myocardial infarction (STEMI) was markedly lower in patients with previous revascularization. Despite these differences, the incidence of 1-year MACE did not differ significantly, and survival analysis revealed no significant divergence in event-free survival. Conclusion ACS patients with prior coronary revascularization carried a higher burden of comorbidities yet were less likely to present with STEMI. Their 1-year outcomes were comparable to first-time ACS patients, suggesting that contemporary secondary prevention strategies and optimized therapy may mitigate the traditionally elevated risk of recurrent ACS. These findings highlight the impact of sustained GDMT in preventing total coronary occlusion and improving long-term prognosis in this high-risk population.Patient characteristicsMACE