Long-term Safety And Efficacy Of Domestic Sirolimus-Eluting Stents For The Treatment Of Coronary Artery Disease In "Real-World" Practice

Objective:This study sought to evaluate the long-term safety and efficacy of domestic Sirolimus-Eluting Stents for the treatment of coronary artery disease in daily practice. The relationship between dual antiplatelet therapy and long-term prognosis after percutaneous coronary intervention were also discussed preliminarily.Methods:To retrospectively study the clinical data of 775 CAD patients who had implanted domestic Sirolimus-Eluting Stents from January 2006 to September 2009 in The Second Affiliated Hospital of Dalian Medical University. According to the stents implanted in the same patients or different patients, there were three guoups as follows:group of a biodegradable polymer-coated sirolimus-eluting stent (EXCEL, JW Medical System, Weihai, n=358), group of a durable polymer-coated sirolimus-eluting stent (PARTNER, LP Medical System, Beijing, n=279) and group of stents combined together (n=138). Compare characteristics of the base line, angiography and stent implantation. The incidences of major adverse cardiac events (MACE), stent thrombosis rates and dual antiplatelet therapy during the follow-up period among the three groups were also compared. The MACE included cardiac death, nonfatal myocardial infarction and target vessel revascularization (TVR).Results:Characteristics of the base line, angiography and stent implantation among three groups were similar. Implantation of 1384 domestic Sirolimus-Eluting stents was successfully performed in 775 CAD patients. The whole follow-up period was between zero and fifty months, and the mean follow-up period was 20.0±14.3 months.91 patients were lost to follow-up, and the defaulters among them were 46 ones,34 ones and 11 ones. Accordingly, the rates of the follow-up were 87.2%,87.8% and 92.0% respectively. Results of six-month follow-up period:There were three patients died of cardiac events in EXCEL group. Two of them died of acute myocardial infarction and heart failure respectively in hospital, whereas another died of acute myocardial infarction after the implantation 93 days later. Two patients of PARTNER group and one of combined stents group were all died of acute ST-segment elevation myocardial infarction in hospital. Patients who were died in hospital above were all in 24 hours after stents implantation. Considering no definite thromboses were found during the angiography, they were definded as probable stent thromboses and acute stent thrombosis. There was the other female who underwent target vessel revascularization five days later because of angina pectoris reoccurrence. Definite stent thrombosis was found during PCI and was definited as subacute stent thrombosis. All the patients were followed for six months, the incidences of MACE were 0.8%,0.7% and 1.4% separately. The MACE free survival among three groups were 99.1%,99.3% and 97.7% and the rate of cumulative survival were 99.1%,99.3% and 99.3% respectively. The incidences of stent thrombosis formation were 0.3% (n=1),0.7%(n=2) and 1.4%(n=2) individually. There were no significant differences all above among three groups. Results of all the follow-up period:The clinical cases in EXCEL groups, PARTNER group and group of stents combined implanted included cardiac death (8 [2.2%] vs.6 [2.2%] vs.9 [3.2%], p=0.852), nonfatal myocardialinfar-ction (11 [3.1%] vs.7 [2.5%] vs.3 [2.2%], p=0.830), TVR (4 [1.1%] vs. 9 [3.2%] vs.4 [2.9%], p=0.162) and the cumulative incidences of MACE were (7.0% vs.8.2% vs.7.2%, p=0.830). During forty month follow-up period, the MACE free survival among three groups were 99.1%, 99.3% and 97.7%, and the rate of cumulative survival were 99.1%,99.3% and 99.3% respectively and no significant differences among three groups were found. Follow-up results of duration for dual antiplatelet therapy:the mean duration for clopidogrel administration among three groups was 11.89±6.33 months,11.55±7.16 months and 11.67±6.62 months respectively, and no significant difference was found. Meanwhile, the mean duration for aspirin administration was 21.90±11.91 months, 23.48±14.96 months and 21.98±13.08 months. The mean duration of PARTNER group was prolonged obviously than the combined stents group, and there was significant difference between them. The incidences of stent thrombosis formation were 4.7%(n=17),4.7%(n=13) and 5.1% (n=7) individually. There were no significant differences all above among three groups. The incidences of stent thrombosis formation were 4.7%(n=17),4.7%(n=13) and 5.1%(n=7) separately. There was an inverse correlation between the duration for clopidogrel administration and the incidence of stent thrombosis. The incidences of stent thrombosis, nonfatal myocardial infarction, and the cumulative incidences of MACE were higher after the discontinuation of dual antiplatelet therapy in 6months, and significant differences were found among them.Conclusions:The implantation of domestic biodegradable polymer-coated sirolimus-eluting stent (EXCEL) and group of a durable polymer-coated sirolimus-eluting stent (PARTNER) in the same or different patients are both safe and effective in daily practice. The incidences of stent thrombosis rates are similar in domestic Sirolimus-Eluting Stents. It hints that the incidences of stent thrombosis rates are not related to the degradation of stents. Besides, the duration for clopidogrel administration for at least one year may be more appropriate.