Meta-Analysis Compares Short- and Long-Term DAPT After DES Implantation
July 10, 2017—The Society for Cardiovascular Angiography and Interventions (SCAI) announced the publication of an investigation evaluating the long-term efficacy and safety of long-duration dual antiplatelet therapy (L-DAPT) compared to short-duration DAPT (S-DAPT) after drug-eluting stent (DES) implantation. SCAI noted that that this meta-analysis is the first to compare outcomes between S-DAPT and L-DAPT in a meta-analysis restricted to trials with patient follow-up of 24 months or longer. The study by Abhisek Sharma, MD, et al is available online and will be published as an Editor’s Choice article in the July 2017 issue of Catheterization and Cardiovascular Interventions.
In the SCAI press release, Dr. Sharma commented, “A major limitation of most randomized control trials (RCTs) and previous meta-analyses was a short period of follow-up. Between the small number of stent thrombosis (ST) events due to the low risk of ST with newer generation DES and the possibility that very-late ST events were not captured due to inadequate follow-up, individual trials and even previous meta-analysis were probably underpowered to detect a definitive difference in reduction of very late ST with L-DAPT. This limitation was addressed in our study by pooling data from only those RCTs that have reported outcomes after a follow-up of at least 24 months or longer.”
According to SCAI, the investigators identified five RCTs in which 19,760 patients were randomized to S-DAPT (n = 9,810) and L-DAPT (n = 9,950). Compared with L-DAPT, S-DAPT was associated with a higher rate of myocardial infarction (MI) (odds ratio [OR], 1.48; 95% confidence interval [CI], 1.04–2.10).
There were no significant differences between S-DAPT and L-DAPT in terms of all-cause mortality (OR, 0.9; 95% CI, 0.73–1.12], cardiac mortality (OR, 1.02; 95% CI, 0.8–1.3), ST (OR, 1.59; 95% CI, 0.77–3.27), target vessel revascularization (OR, 0.87; 95% CI, 0.67–1.14), or stroke (OR, 1.08; 95% CI, 0.81–1.46). However, the rate of thrombolysis in myocardial infarction major bleeding was significantly lower with S-DAPT compared to L-DAPT (OR, 0.64; 95% CI, 0.41–0.99).
Dr. Sharma stated, “Our results support the importance of carefully choosing DAPT durations based on an individual patient's ischemic and bleeding risks. However, the clinical trials included in the current meta-analysis have mostly used clopidogrel as a second agent. With the increasing adoption of more potent P2Y12 inhibitors in clinical practice, the relative benefit-to-risk profile of S-DAPT versus L-DAPT using these agents remains to be established in future studies.”