Left main or proximal left anterior descending coronary artery disease location identifies high-risk patients deriving potentially greater benefit from prolonged dual antiplatelet therapy duration.

Abstract

It is currently unclear if the location of coronary artery disease affects decision making with regard to dual antiplatelet therapy (DAPT). We investigated if the presence of at least 30% luminal narrowing in the left main (LM) and/or proximal left anterior descending (pLAD) coronary arteries on angiography is an outcome modifier with respect to DAPT duration. In the Prolonging Dual Antiplatelet Treatment After Grading Stent-Induced Intimal Hyperplasia (PRODIGY) study, 953 (54.3%) patients with and 801 (45.7%) without LM/pLAD lumen narrowing at the qualifying coronary intervention were randomised to six or 24 months of DAPT. Twenty-four month as compared to six-month DAPT reduced the occurrence of definite, probable or possible stent thrombosis by 50% in patients with (2.8% vs. 5.6%; HR 0.45, 95% CI: 0.23-0.89; p=0.02) but not in those without LM/pLAD lumen narrowing, with a highly significant interaction testing (PINT= 0.002). This result remained consistent irrespective of whether stenting was (PINT: 0.01) or was not (PINT: 0.02) performed in the LM/pLAD. Left main and/or proximal LAD lumen narrowing may be a treatment modifier with respect to the duration of DAPT. Patients fulfilling these angiographic characteristics seem to benefit from a prolonged dual antiplatelet treatment. Trial registration: ClinicalTrials.gov Identifier: NCT00611286