Temporal patterns of the association between Achilles tendon thickening and clinical outcomes after percutaneous coronary intervention in acute and chronic coronary syndromes

Although Achilles tendon thickening (ATT) is associated with adverse outcomes after percutaneous coronary intervention (PCI), whether its prognostic impact differs over time between acute (ACS) and chronic coronary syndromes (CCS) remains unclear. We retrospectively analyzed 1,362 patients who underwent successful PCI and assessment of ATT using soft X-ray radiography. ATT was defined as Achilles tendon thickness ≥8.0 in men and ≥7.5 mm in women. MACE, including death, myocardial infarction, stent thrombosis, stroke, and target vessel revascularization, were investigated for up to 3 years. To evaluate temporal differences, we conducted the Kaplan-Meier method with landmark analysis and time-segmented Cox proportional hazards analyses dividing follow-up into ≤ 1 year and 1-3 years after PCI. ATT was observed in 228 patients (16.7%), who had a significantly higher incidence of MACE compared to patients without ATT. In ACS patients (n = 387), ATT was independently associated with an increased risk of MACE within 1 year, but not beyond 1 year. Conversely, in CCS patients (n = 975), ATT was not associated with early events, but was significantly associated with increased MACE risk during 1-3 years after PCI. Similar trends were observed after excluding familial hypercholesterolemia. These findings suggest different temporal patterns in the association between ATT and MACE after PCI in patients with ACS and CCS, which may provide additional insights into risk stratification during follow-up.