Recurrent acute coronary syndrome and mechanisms of plaque instability

Patients with an acute coronary syndrome (ACS) due to plaque rupture had a worse prognosis when compared with those without plaque rupture with a higher rate of target vessel revascularization and readmission for unstable angina, suggesting that both stent failure and disease progression occur more frequently. However, it is not known whether recurrent episodes of coronary instability in the same patient are caused by the same pathogenetic mechanism. Thus, we sought to investigate the mechanisms of coronary instability imaged by optical coherence tomography in patients with recurrent ACS events. The present case series, with 4 patients having recurrent ACS, shows that the same mechanism of coronary instability is present during both first and recurrent instability. This hypothesis-generating finding may support further studies targeted at assessing the mechanisms of coronary instability recurrence and how to tailor preventive measures to the underlying mechanism of instability.