Balancing the risks of restenosis and stent thrombosis in bare-metal versus drug-eluting stents: results of a decision analytic model.
OBJECTIVE
We sought to define what incremental risk of very late stent thrombosis (VLST) in drug-eluting stents (DES) would outweigh the restenosis benefit.


BACKGROUND
Although there are robust data on the restenosis benefit of DES versus bare-metal stents (BMS), the incremental risk of stent thrombosis, a rare but serious complication of percutaneous coronary intervention (PCI), is not known with certainty.


METHODS
We developed a decision analytic Markov model comparing DES versus BMS strategies for a contemporary PCI population. Procedure-related morbidity and mortality data from published reports were used to derive the model probabilities. Over a range of incremental risk and duration of risk of VLST, we identified the net benefit of DES versus BMS in terms of quality-adjusted life expectancy (QALE).


RESULTS
Under an assumption of equal stent thrombosis rates beyond 1 year, the DES strategy was superior to BMS in terms of QALE (16.262 vs. 16.248 quality-adjusted life years [QALYs], difference = 0.014). Under the alternative assumption of an incremental risk difference of 0.13%/year, the net benefit was substantially reduced (difference = 0.001 QALYs). The threshold excess risk of very late DES thrombosis compared with BMS, above which BMS would be the preferred strategy, was 0.14%/year (over 4 years of follow-up). This threshold increased as the population risk of restenosis increased and decreased as the vulnerable time window lengthened.


CONCLUSIONS
A small absolute increase in DES thrombosis compared with BMS after 1 year (>0.14%/year) would result in BMS being the preferred strategy for the overall PCI population. Larger clinical trials with longer follow-up are needed to estimate the risk of late stent thrombosis with greater certainty for existing and new DES.
Garg
Pallav
P
Division of Cardiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Cohen
David J
DJ
Gaziano
Thomas
T
Mauri
Laura
L
D015906:Angioplasty, Balloon, Coronary; D023903:Coronary Restenosis / Q000517:prevention & control*; D003328:Coronary Thrombosis / Q000517:prevention & control*; D003661:Decision Support Techniques; D054855:Drug-Eluting Stents; D006801:Humans; D008390:Markov Chains; D019057:Quality-Adjusted Life Years; D012306:Risk; D018570:Risk Assessment; D012307:Risk Factors