Author + information
- Antonio Colombo, MD∗ ( and )
- Francesco Giannini, MD
- ↵∗Address for correspondence:
Dr. Antonio Colombo, San Raffaele Scientific Institute, Via Olgettina 60, 20132 Milan, Italy.
- complex lesions
- dual antiplatelet therapy
- dual antiplatelet therapy score
- percutaneous coronary intervention
Prolonged dual antiplatelet therapy (DAPT) after coronary stenting has been associated with a reduction in ischemic events at the expense of higher bleeding. There is a valuable need to define the “sweet spot” for a specific patient where we optimize the benefits of DAPT with minimal associated risks.
Intuitively, lesion complexity is a variable associated with a higher risk for ischemic events; therefore, the decision to extend DAPT duration seems appropriate. This concept is supported by a pooled analysis of different trials demonstrating an additional benefit of prolonged DAPT in patients with complex anatomy (1). This study evaluated the effect of lesion complexity (3 vessels treated, 3 stents implanted, 3 lesions treated, bifurcation with 2 stents implanted, total stent length >60 mm, or chronic total occlusion as the target lesion) upon DAPT duration of 6 months versus 12 months. The definition adopted for lesion complexity was, in our view, more realistic compared with the pre-specified definition applied in the DAPT trial (2). In addition, the study of Giustino et al. (1) evaluated the effect of DAPT between 6 and 12 months and not after 12 months.
The specific analysis from the DAPT Trial (3) in this issue of the Journal evaluates if stenting complex lesions benefits from prolonged DAPT (12 months vs. 30 months; event rates evaluated after 12 months from stent implantation).
A lesion was considered complex if any of the following was present: unprotected left main, >2 lesions per vessel, lesion length ≥30 mm, bifurcation lesion with side branch ≥2.5 mm, lesion located on a saphenous vein graft, and thrombus-containing lesion.
An important initial consideration is that patients randomized in the DAPT trial represent a relatively low-risk population. These are patients who did not experience adverse events in the first year following stent implantation.
Complex lesions were present in 45.5% of the 11,554 patients randomized. Most of the patients with complex lesions had only 1 complex feature. The ischemic endpoint was myocardial infarction or stent thrombosis, and the safety endpoint was moderate or severe bleeding events according to GUSTO (Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Arteries) criteria and was evaluated between 12 and 30 months. As expected, patients with complex lesions experienced more adverse events compared with patients without complex lesions between 0 and 12 months (major adverse cardiovascular and cerebrovascular events: 5.3% vs. 3.5%; p < 0.001; myocardial infarction or stent thrombosis: 3.9% vs. 2.4%; p < 0.001). There was no difference in moderate or severe bleeding (2.2% vs. 2.4%; p = 0.40). Regarding the primary endpoint of the study, there were no differences in ischemic events between 12 and 30 months in patients with versus without complex lesion characteristics (3.5% vs. 2.9%; p = 0.07). However, there was a trend toward increased events in patients with more complex lesion features. Nevertheless, the extended duration of DAPT was effective to reduce ischemic events in all type of lesions, and treatment effects were not greater in lesions with more complex characteristics. Moreover, lesion complexity did not affect the incidence of safety endpoints.
In addition to lesion complexity, the authors analyzed the effect of DAPT score (4). This score is as follows: 1 point for myocardial infarction at presentation, prior myocardial infarction, prior percutaneous coronary intervention, diabetes, stent diameter <3 mm, smoking, and paclitaxel-eluting stent; 2 points for history of congestive heart failure/low ejection fraction and vein graft intervention; −1 point for age between 65 and 75 years; and −2 points for age >75 years. A value ≥2 was used as a cutoff point to define a high-risk group for thrombotic events. A total of 61% of patients with complex lesions had a high DAPT score, and in these patients, prolonged DAPT significantly reduced the ischemic event rate (3% for extended DAPT vs. 6.1% for placebo; p < 0.001), maintaining the low rate of moderate or severe bleeding (1.7% for extended DAPT vs. 1.4% for placebo; p = 0.61). Prolonged DAPT was also significantly beneficial to reduce ischemic events in patients without complex lesions provided they had a high DAPT score.
From this study, we have learned the following:
1. Lesion complexity determines the occurrence of adverse events mainly in the first 6 months after stenting.
2. The influence on patient outcomes of a complex lesion may depend upon its definition.
3. The introduction of second-generation drug-eluting stents may further curtail the effect of lesion complexity.
4. Patient-related factors, as evaluated by the DAPT score, are important determinants of adverse events.
5. Extending the duration of DAPT treatment in patients with complex lesions and DAPT scores ≥2 does not increase the amount of bleeding events.
6. The decision to extend the duration of the DAPT should be based on patient-related factors.
As the authors suggest, lesion complexity may not affect the benefits of DAPT duration because of a need to protect the entire coronary tree as opposed to the stented/treated segments. This need is better expressed by patient-related factors, whereas lesion complexity remains an indirect marker of disease burden. The power of lesion complexity to be a marker for disease burden depends upon the definition of a complex lesion.
↵∗ Editorials published in the Journal of the American College of Cardiology reflect the views of the authors and do not necessarily represent the views of JACC or the American College of Cardiology.
Both authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- 2017 American College of Cardiology Foundation
- Giustino G.,
- Chieffo A.,
- Palmerini T.,
- et al.
- Yeh R.W.,
- Kereiakes D.J.,
- Steg P.G.,
- et al.,
- on behalf of the DAPT Study Investigators
- Yeh R.W.,
- Secemsky E.A.,
- Kereiakes D.J.,
- et al.