Abstract
BACKGROUND: Primary percutaneous coronary intervention (PCI) is the preferred reperfusion strategy compared with onsite fibrinolytic therapy (O-FT) for ST-segment-elevation myocardial infarction when delivered promptly. However, the contemporaneous data to inform the comparative benefits of primary PCI versus O-FT, especially in developing countries, have been largely understudied. METHODS: We used data from the National Chest Pain Center Program (NCPCP), the largest nationwide registry in China, including patients with ST-segment-elevation myocardial infarction treated with primary PCI or O-FT from January 2016 to December 2022. Patients were matched using propensity scores, and the PCI-related delay was defined as the difference between the observed door-to-wiring time and the door-to-needle time. Mortality outcomes were assessed at different delay intervals (<60 minutes, 60-90 minutes, >90 minutes). Subgroup analyses were conducted based on age, infarction location, and Killip classification. RESULTS: In 19 334 matched patients, primary PCI demonstrated a significant mortality benefit over O-FT when PCI-related delays were <60 minutes (2.34% versus 6.01%). However, this advantage diminished when delays exceeded 90 minutes. The critical threshold at which PCI lost its mortality benefit was identified as 119.51 minutes (door-to-wiring time - door-to-needle time). Subgroup analyses showed that older patients, patients with anterior infarction, and those with a higher Killip class appeared to have lower equipoise thresholds. CONCLUSIONS: Primary PCI offers a mortality benefit compared with O-FT in patients with timely treated ST-segment-elevation myocardial infarction, but treatment delays can mitigate this benefit. In settings with prolonged treatment delays, immediate fibrinolysis may be a more effective strategy. Treatment decisions should incorporate both patient characteristics and health care system constraints to optimize ST-segment-elevation myocardial infarction outcomes.