Abstract Number: PB1387
Meeting: ISTH 2020 Congress
Theme: Platelet Disorders and von Willebrand Disease » Antiplatelet Therapy
Background: Long-term stability of platelet reactivity has been prospectively demonstrated in small, non-high-risk populations on dual antiplatelet therapy (DAPT) with clopidogrel and aspirin.
Aims: Aim of our study was 1) to investigate whether platelet function testing (PFT) performed 1 month after percutaneous coronary intervention (PCI) remains stable for the total treatment duration with DAPT in a specifically high-risk, vulnerable patient group, and 2) to compare stability in 3 different, simultaneously measured PFTs.
Methods: In this prospective study 123 patients were included with ≥3 risk factors on DAPT consisting of clopidogrel (n=95), prasugrel (n=22) or ticagrelor (n=6) in combination with aspirin (n=106) and/or anticoagulants (n=19). Platelet reactivity was measured after a median of 45 [36-57] (T1) and 198 [184-215] (T2) days post-PCI, using three different PFTs; Multiplate ADP, light transmission aggregometry (LTA ADP) and VerifyNow P2Y12. According to consensus-based therapeutic windows (JACC 2013), patients were classified in categories of high, optimal or low on-treatment platelet reactivity (HTPR, OTPR and LTPR, respectively) at both time points.
Results: As shown in table 1, median platelet reactivity at T1 and T2 was stable when measured with Multiplate and LTA, whereas VerifyNow demonstrated a small decrease from 150.0 [69.0-207.3] to 140.5 [57.5-200.5] PRU (p=0.03). Figure 1 shows that 72.9-81.3% of patients were classified in the same platelet reactivity category at both time points, while their classification increased in 7.4-14.4% (e.g. from LTPR to OTPR) and decreased in 11.1-15.8% (e.g. from HTPR to OTRP).
Conclusions: In this high-risk population, platelet reactivity measured by Multiplate and LTA is stable from 45 to 198 days post-PCI, contrary to VerifyNow, which demonstrated a significant, but probably clinically irrelevant, decrease of 9.5 PRU (therapeutic window: 85-208 PRU). Thus, PFTs performed 1 month post-PCI could possibly assist in risk assessment of high-risk, vulnerable patients using DAPT, without the need for repetitive measurements.
| Platelet function test | Platelet reactivity T1, median [IQR] | Platelet reactivity T2, median [IQR] | Pairwise comparison Wilcoxon Signed Rank test, p |
| Multiplate ADP (6.4 μmol/L) (AU) | 47.0 [34.5-66.0] | 47.5 [31.0-70.5] | 0.34 |
| LTA ADP (20 μmol/L) (% max. aggr.) | 39.0 [25.5-48.6] | 41.0 [27.0-49.0] | 0.41 |
| VerifyNow P2Y12 (20 μmol/L) (PRU) | 150 [69.0-207.3] | 140.5 [57.5-200.5] | 0.03 |
[Table 1: Pairwise comparison of median residual platelet reactivity between T1 and T2 in three platelet function tests]
[Figure 1: Distribution of patients switching between platelet reactivity categories between both time points as measured with 3 PFTs Click to previe]
To cite this abstract in AMA style:
Olie R, Roelofs J, Veenstra L, Henskens Y, Vries M, van der Meijden PEJ, ten Cate H. Long-term Variation of Platelet Reactivity in High-Risk Patients on Antiplatelet Therapy after Percutaneous Coronary Intervention [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/long-term-variation-of-platelet-reactivity-in-high-risk-patients-on-antiplatelet-therapy-after-percutaneous-coronary-intervention/. Accessed November 29, 2023.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/long-term-variation-of-platelet-reactivity-in-high-risk-patients-on-antiplatelet-therapy-after-percutaneous-coronary-intervention/