Is there any Difference in Rate of Acute Complications - Especially Stent Thrombosis - Between Bare Metal and Drug Eluting Stents?

Background- Although bare metal stents (BMS) resolved abrupt closure which was the most important complication of percutaneous coronary balloon angioplasty, and then drug-eluting stents (DES) significantly reduced the rate of restenosis that was seen in around 30% to 40% at mid-term of post-percutaneous coronary intervention (PCI), but stent thrombosis is still a major problem which occurs in different phases. This study was conducted to evaluate the rate of acute complications, especially acute stent thrombosis (in the first 24 hours) in patients who received either BMS or DES.Method- This retrospective study was performed on 1674 patients (640 women and 1034 men) who underwent PCI with at least one stent (from 2002 until 2006). 2404 stents were deployed, 975 BMS (40%) and 1429 DES (60%), (820 Cypher, 570 Taxus and 39 other kinds). 705 stents (35%) were deployed directly and 1699 stents (65%) followed pre-dilatation.Results- In 35 cases (2%), the procedure was not completed because of several reasons (failure of guiding catheter engagement, failure to cross the lesions by guidewires or balloon catheters). Fourteen patients (0.8%) suffered acute stent thrombosis (eight in the DES and six in the BMS groups), one of whom was referred for emergency coronary bypass surgery (CABG) and twelve patients treated by re-PCI. One patient was complicated by embolic occlusion of a dominant LCX during manipulation of the guiding catheter that was referred to emergency CABG. Two patients suffered left main (LM) dissection, one of whom was treated by prompt stenting and the other after stabilizing by LM stenting, was referred for urgent CABG. Fifteen cases (0.8%) developed slow or no-reflow phenomenon (six cases in the BMS and nine cases in the DES groups) who were managed by medical and mechanical intervention. Twenty five cases (1.5%) had mild CPK-MB rising (ten patients in the BMS and fifteen patients in the DES groups). Totally 0.3% of cases were referred for emergency or urgent and (1.7%) for elective CABG. Fortunately there was no in-hospital death.Conclusion- This study showed a low and similar incidence of acute complications, especially acute stent thrombosis, in PCI in both BMS and DES groups