Garg Pallav, Galper Benjamin Z, Cohen David J, Yeh Robert W, Mauri Laura
Division of Cardiology, London Health Sciences Center, London, Ontario, Canada.
Division of Cardiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
Am Heart J. 2015 Feb;169(2):222-233.e5. doi: 10.1016/j.ahj.2014.11.002. Epub 2014 Nov 10.
After coronary stent placement, whether dual antiplatelet therapy (DAPT) duration should be extended to prevent late stent thrombosis (ST) or adverse cardiovascular events is uncertain.
To define the reduction in ischemic events required to outweigh increased bleeding with longer-duration DAPT, we developed a decision-analytic Markov model comparing DAPT durations of 6, 12, and 30 months after DES. Separate models were developed for patients presenting with and without an acute coronary syndrome (ACS). We used sensitivity analyses to identify the incremental benefit of longer-duration DAPT on either ST or the composite of cardiac death, myocardial infarction, and ischemic stroke (major adverse cardiovascular and cerebrovascular events [MACCEs]) required to outweigh the increased risk of bleeding associated with longer DAPT. The outcome from each strategy was quantified in terms of quality-adjusted life years.
In the non-ACS population, in order for 30 months of DAPT to be preferred over 12 months of therapy, DAPT would have to result in a 78% reduction in the risk of ST (relative risk [RR] 0.22, 3.1 fewer events per 1000) and only a 5% reduction in MACCE (RR 0.95, 2.2 fewer events per 1000) as compared with aspirin alone. For the ACS population, DAPT would have to result in a 44% reduction in the risk of ST (RR 0.56, 3.4 fewer events per 1000) but only a 2% reduction in MACCE (RR 0.98, 2.3 fewer events per 1000) as compared with aspirin alone, for 30 months of DAPT to be preferred for 12 months.
Small absolute differences in the risk of ischemic events with longer DAPT would be sufficient to outweigh the known bleeding risks.
冠状动脉支架置入术后,双联抗血小板治疗(DAPT)疗程是否应延长以预防晚期支架内血栓形成(ST)或不良心血管事件尚不确定。
为了确定延长DAPT疗程以抵消出血增加所需的缺血事件减少量,我们开发了一个决策分析马尔可夫模型,比较药物洗脱支架(DES)置入术后6、12和30个月的DAPT疗程。针对有和没有急性冠状动脉综合征(ACS)的患者分别建立了模型。我们使用敏感性分析来确定延长DAPT疗程对ST或心源性死亡、心肌梗死和缺血性卒中复合事件(主要不良心血管和脑血管事件[MACCE])的增量益处,以抵消延长DAPT疗程相关的出血风险增加。每种策略的结果以质量调整生命年进行量化。
在非ACS人群中,为了使30个月的DAPT优于12个月的治疗,与单独使用阿司匹林相比,DAPT必须使ST风险降低78%(相对风险[RR]0.22,每1000例事件减少3.1例),而MACCE仅降低5%(RR 0.95,每1000例事件减少2.2例)。对于ACS人群,与单独使用阿司匹林相比,为了使30个月的DAPT优于12个月的治疗,DAPT必须使ST风险降低44%(RR 0.56,每1000例事件减少3.4例),而MACCE仅降低2%(RR 0.98,每1000例事件减少2.3例)。
延长DAPT疗程导致的缺血事件风险的微小绝对差异足以抵消已知的出血风险。