SOLACI | Latin American Society of Interventional Cardiology

Original Title: 6-Month versus 12-Month Dual-Antiplatelet Therapy Following Long Everolimus-Eluting Stent Implantation. The IVUS-XPL Randomized Clinical Trial.

Reference: Hong et al. JACC Cardiovasc Interv. 2016 May 11. [Epub ahead of print]

Courtesy of Dr. Brian Nazareth Donato.

This publication stems from the IVUS-XPL published by JAMA in November 2015. This study presents outcomes on the safety of a 6-month dual antiplatelet therapy (DAPT) post PCI with everolimus eluting stents (EES – Xience Prime) vs. a 12-month DAPT, in long lesions.

With a 2×2 factorial design, researchers analyzed a total 1,400 patients to be treated between June 2010 and July 2014 in twenty centers across Korea, randomized to 6 vs. 12 months DAPT (ASA + clopidogrel) and angiography-guided PCI vs. intravascular ultrasound (IVUS) guided PCI.

Primary end point was a composite of cardiovascular death, MI, stroke, stent thrombosis and major bleeding. There were no significant differences.

The 6-month DAPT group presented an events rate of 2.2 %
The 12-month DAPT group presented an events rate of 2.1 %

[p= 0.99]

Neither were there statistically significant differences between the subgroups presented at randomization outset:

Acute coronary syndromes (SCA), with 2.4 % rate in both branches.
Diabetic patients with 2.2% events rate at 6 months and 3.3% at 12 months

[p=0.42]

At post hoc analyzis, there was significant interaction[p=0.018] between the use of IVUS and DAPT duration, with better evolution of patients in the IVUS and 6-month DAPT group, probably because stent optimization leads to the same number of ischemic events with lower bleeding rate.

Conclusion

The 6-month DAPT showed no differences in cardiac death, MI, stroke, stent thrombosis or major bleeding compared to the standard 12-month DAPT in patients undergoing PCI with EES.

Editorial Comment

At present the AHA guidelines continue to recommend 12-month DAPT after DES stenting, a recommendation that differs from the European guidelines for patients with stable heart disease undergoing second generation DES stenting.

However, well designed studies looking at the use of DAPT after DES stenting show contradicting outcomes and different evolution between first and second generation DES, in general, in low complex lesions.

The present study is for a shorter DAPT, this time in long lesions, with everolimus eluting stents only. The greatest limitations to this study are two: on one hand, it has little statistical power because of a rather low events rate; on the other hand, it does not use placebo beyond 6 months.

Even though shown by these study outcomes, the use of ultravascular ultrasound and shorter DAPT for better evolution should be considered with caution, in the light of the fact that these study subgroups have very low events rates.

Courtesy of Dr. Brian Nazareth Donato. Buenos Aires British Hospital, Argentina.