A real-world, all-comers, registry—published in EuroIntervention and presented at EuroPCR (21–24 May, Paris, France)—has suggested that the incidence of stent thrombosis is 1.9% and cardiogenic shock (often excluded in clinical trials) is the strongest independent predictor for the complication.
Javaid Iqbal (Department of Cardiovascular Science, University of Sheffield, Sheffield, UK) and colleagues, wrote there was a need for contemporary registries to examine the incidence and risk of stent thrombosis because “The clinical trials tend to present stent thrombosis rates for a particular type of stent used in a selected patient cohort, whereas the registry data can evaluate the stent thrombosis in a real-life experience in a certain geographical area.” Therefore, the authors conducted a retrospective analysis of prospectively collected data of patients undergoing percutaneous coronary intervention (PCI) to examine the incidence of stent thrombosis and its risk factors in a real-world, all-comers setting.
Of the 5,833 patients who underwent PCI during the study period (2007–2010), 109 (1.9%) had stent thrombosis (70 definite; 39 probable). According to Iqbal et al, this figure is similar to the incidence of stent thrombosis in other contemporary registries. They also commented: “Eighty per cent of definite stent thrombosis presented as acute myocardial infarction and 20% as unstable angina. Six per cent of cases of probable stent thrombosis presented at deaths, 27% as acute myocardial infarction, and 13% as unstable angina.”
In a multivariate analysis, cardiogenic shock was found to be an independent predictor of both definite/probable stent thrombosis and definite stent thrombosis alone. Iqbal and others noted: “This has not been previously reported because these very high-risk patients are commonly excluded from trials and are underrepresented even in registries.” They added that the presence of cardiogenic shock could have “important implications for the choice of antiplatelet therapy and revascularisation strategy”, explaining that intravenous antiplatelet therapies may have a role in patients with cardiogenic shock to overcome problems with other therapies. According to the authors, in these patients, the bioavailability of thienopyridine-type antiplatelets may be reduced in cardiogenic shock and the non-thienopyridine oral P2Y12 ticagrelor may also have a delayed onset of action in ST-elevation myocardial infarction (STEMI) patients with cardiogenic shock.
Other independent predictors of definite/probable stent thrombosis included lack of dual antiplatelet therapy, diabetes, stent length, stent diameter, type of stent, and three-vessel PCI. Also, Iqbal and colleagues found that cardiogenic shock, stent size, STEMI, diabetes, and three-vessel PCI were associated with early stent thrombosis while lack of dual antiplatelet therapy was associated with late stent thrombosis. Stent length, STEMI, and use of first-generation drug-eluting stents were associated with delayed stent thrombosis. Iqbal et al commented: “It is generally advocated that STEMI patients presenting with cardiogenic shock should have complete (as opposed to culprit-only) revascularisation. However, our results highlighting a very high incidence of stent thrombosis in this cohort provide a note of caution.”