Deferred stent implantation in patients with ST-segment elevation myocardial infarction: a pilot study

Aims: Disturbance in the flow of an infarct-related artery due to embolisation of thrombus and plaque material occurs frequently during primary percutaneous coronary intervention (PCI) and is associated with impaired prognosis. The aim of the present study was to minimise the risk of embolisation during PCI in patients with ST-segment elevation myocardial infarction (STEMI). Methods and results: Of 124 consecutive patients with STEMI, thrombectomy and/or balloon dilatation was performed in 110 (89%). Stent implantation was deferred in 113 (91%) patients who then comprised the study group. In 38% of the patients stent implantation was deemed unnecessary at the second examination because of <30% residual stenosis and no visible thrombus, and all lesions re-examined three months later were patent. Major adverse cardiac events occurred in two patients during eight months of follow-up (one cardiac death, one case of reinfarction with target lesion revascularisation). In five patients no PCI was performed at all. Myocardial salvage determined by cardiac magnetic resonance in a subset of patients was relatively high. Conclusions: Deferred stent implantation is safe in the majority of patients with STEMI. Although the concept has to be evaluated in a randomised trial, the strategy may prove beneficial for many patients referred for primary PCI.