Impaired endogenous fibrinolysis in ST-segment elevation myocardial infarction patients undergoing primary percutaneous coronary intervention is a predictor of recurrent cardiovascular events: the RISK PPCI study

The endogenous fibrinolytic system serves to prevent lasting thrombotic occlusion and infarction following initiation of coronary thrombosis. We aimed to determine whether impaired endogenous fibrinolysis can identify patients with ST-segment elevation myocardial infarction (STEMI) who remain at high cardiovascular risk despite dual antiplatelet therapy (DAPT).

A prospective, observational study was conducted in 496 patients presenting with STEMI for primary percutaneous coronary intervention (PPCI). Blood was tested on arrival pre-PPCI, at discharge and at 30 days to assess thrombotic status using the automated point-of-care global thrombosis test and patients followed for 1 year for major adverse cardiovascular events (MACEs). Endogenous fibrinolysis was significantly impaired [baseline lysis time (LT) ≥2500 s] in 14% of patients and was highly predictive of recurrent MACE [hazard ratio (HR) 9.1, 95% confidence interval (CI) 5.29–15.75; P < 0.001], driven by cardiovascular death (HR 18.5, 95% CI 7.69–44.31; P < 0.001) and myocardial infarction (HR 6.2, 95% CI 2.64–14.73; P < 0.001), particularly within 30 days. Fibrinolysis remained strongly predictive of MACE after adjustment for conventional risk factors (HR 8.03, 95% CI 4.28–15.03; P < 0.001). Net reclassification showed that adding impaired fibrinolysis improved the prediction of recurrent MACE by >50% (P < 0.001). Patients with spontaneous ST-segment resolution pre-PPCI had more rapid, effective fibrinolysis [LT 1050 (1004–1125) s vs. 1501 (1239–1997) s, P < 0.001] than those without. Lysis time was not altered by standard of care STEMI treatment including DAPT and was unchanged at 30 days.

Endogenous fibrinolysis assessment can identify patients with STEMI who remain at very high cardiovascular risk despite PPCI and DAPT. Further studies are needed to assess whether these patients may benefit from additional, personalized antithrombotic/anticoagulant medication to reduce future cardiovascular risk.

http://www.clinicaltrials.gov. Unique identifier: NCT02562690.