After 10 years, unstable or chronic coronary patients revascularized with drug-eluting stents (DES) had similar, very good outcomes regardless of whether the DES did or did not have a polymer, according to the ISAR-TEST-5 study, recently published in J Am Coll Cardiol.

The 10-year device-oriented endpoints occurred in 43.8% of patients treated with a polymer-free sirolimus-eluting stent and 43.0% of those treated with a durable-polymer zotarolimus-eluting stent.

The somewhat disappointed authors confessed that they had expected results to favor polymer-free devices over the longer-term follow-up, but that was not the case at all.

At the end of the follow-up, there was no difference between polymer-free technology and permanent-polymer devices. This is not necessarily bad news, since the long-term safety and efficacy of this new technology were confirmed. This is something that other apparently promising technologies could not achieve.

Read also: ESC 2019 | ISAR-REACT 5 | Which Is Better in ACS, Prasugrel or Ticagrelor?

Polymer-free stent technology was developed due to concerns about the inflammatory effect of the durable polymer after the drug is released. Delayed arterial healing and de novo atherosclerosis within the treated segment were partially attributed to the polymer.

In the ISAR-TEST-5 study, the rate of definite or probable stent thrombosis was very low and similar for the devices. Between 1 and 10 years, the rate of stent thrombosis was 0.5% with polymer-free DES and 0.7% with durable-polymer DES (p = 0.52). The very late stent thrombosis rates for both technologies fall below 1%, confirming their greater safety compared with first-generation drug-eluting stents.

The study included 2002 patients treated with polymer-free DES and 1000 patients treated with permanent-polymer DES. About 30% of subjects had a history of infarction and 10% had previous bypass surgery. Approximately 60% of procedures were scheduled, 30% were related to unstable angina, and 10% were related to acute infarction.

Read also: TCT 2019 | IDEAL-LM: Bioabsorbable Polymer DES vs. Permanent Polymer DES for Left Main Stenosis.

At one year, the polymer-free DES proved to be noninferior to the Resolute device as regards cardiac death, target-vessel infarction, and target lesion revascularization. Researcher hopes were put on long-term results, but at 5 years there were no differences; now, we know that there are no differences at 10 years either.

Original title: 10-year outcomes from a randomized trial of polymer-free versus durable polymer drug-eluting coronary stents.

Reference: Kufner S et al. J Am Coll Cardiol. 2020;76:146-158.

We are interested in your opinion. Please, leave your comments, thoughts, questions, etc., below. They will be most welcome.