AT EuroPCR 2015
PARIS (FRONTLINE MEDICAL NEWS) – A novel method of quantifying the risks of major bleeding and stent thrombosis may guide decisions about the duration of dual-antiplatelet therapy in stent recipients, according to Dr. Francesco Costa.
It’s a two-pronged approach that relies upon a CRUSADE bleeding risk score greater than 40 as a red flag cautioning against 24 months of dual-antiplatelet therapy (DAPT) in favor of 6 months, while also taking into consideration the anatomic location of an individual’s coronary artery disease as a guide to ischemic risk, such as stent thrombosis, Dr. Costa said at the annual congress of the European Association of Percutaneous Cardiovascular Interventions.
A patient with at least 30% luminal narrowing of the left main coronary artery and/or the proximal LAD (left anterior descending) artery is at markedly reduced risk of stent thrombosis with a DAPT regimen of 24 months rather than 6 months, according to Dr. Costa of Erasmus University in Rotterdam, the Netherlands. These findings were borne out in a retrospective analysis of data from the previously published PRODIGY trial , in which 2,013 patients undergoing percutaneous coronary intervention were randomized to receive a first- or second-generation drug-eluting stent or a bare metal stent, and then further randomized to 6 or 24 months of DAPT (Circulation 2012;125:2015-26).
As these findings about how to guide DAPT duration come from an exploratory retrospective analysis, Dr. Costa stressed, they must be considered hypothesis generating. A definitive prospective randomized trial is warranted to confirm the hypothesis. Such a trial is sorely needed, the cardiologist added.
“International guidelines suggest tailoring DAPT duration according to a patient’s ischemic and bleeding risks. However, currently a reproducible method of weighing these risks has not yet been proposed,” he said. “I think if we put 10 different [physicians] in front of a patient and asked them to define that patient’s bleeding risk, almost everyone would have a different idea.”
The PRODIGY-tested approach, while not ideal, is a definite step forward, according to Dr. Costa.
He and his coworkers evaluated three different bleeding risk scoring systems – HAS-BLED , ACUITY, and CRUSADE – before concluding that a CRUSADE score greater than 40 was superior as a predictor of major bleeding in the PRODIGY population.
Roughly 16% of participants in this all-comers study had a CRUSADE score above 40. A 24-month course of DAPT in this group was associated with a 2.7-fold increased risk of major bleeding events, compared with a 6-month course. The number-needed-to-harm with a 24-month course of DAPT was 17, compared with a number-needed-to-harm of 67 in an unselected population. In contrast, there was no significant increase in major bleeding risk with 24 months of DAPT in patients with a CRUSADE score of 40 or less.
Patients with a CRUSADE score greater than 40 also had a sharply increased need for RBC transfusion if they were on 24 months of DAPT.
The investigators chose 30% luminal narrowing of the left main or proximal LAD coronary arteries as their cutpoint for increased risk of ischemic events during follow-up because they consider it a good marker for more diffuse atherosclerotic disease.
PRODIGY participants with luminal narrowing at either location were 55% less likely to experience stent thrombosis with 24 months of DAPT than with 6.
Dr. Andreas Baumbach said the DAPT decision-making aid presented by Dr. Costa is just what interventional cardiologists have been looking for.
“We’re always talking about patients at high bleeding risk and high ischemic risk, but we haven’t really had a tool to identify those other than our clinical judgment, thinking that high bleeding risk comes with age and renal impairment. So to have a score that’s almost validated for this purpose is really important,” according to Dr. Baumbach, professor of interventional cardiology at the University of Bristol (England).
This analysis was conducted without external funding. Dr. Costa reported having no relevant financial conflicts.
