According to European guidelines, patients with stable coronary disease should undergo moderate-to-vigorous intensity exercise. Intense physical activity may have a negative impact on platelet aggregation and the protective effect of antiplatelet (AP) drugs is not documented. The aim of our study was to assess the effect of aspirin (ASA) and P2Y12 receptors antagonists (P2Y12-RA), before and immediately after intense physical activity.

We performed a prospective single center cross-over study. Patients had to be treated with dual AP therapy including ASA and P2Y12-RA (Clopidogrel or Prasugrel), at least 6 months after an acute coronary syndrome (ACS) but less than the recommended one year, in the absence of significant left ventricular sequelae or residual ischemia. A first Stress test was done with ASA and Clopidogrel or Prasugrel, then, after 2 weeks, the P2Y12-RA was switched (Prasugrel instead of Clopidogrel and vice versa) and a second Stress test was performed. Platelet responses were analyzed by Aspirin Reaction Units (ARU) and P2Y12 Reaction Units (PRU) measurements, before and immediately after Stress test.

23 patients (all men; mean age 57, 7 years) undertaking dual AP therapy (ASA-75mg plus Prasugrel-10mg or ASA-75mg plus Clopidogrel-75mg per day) were recruited. Mean Peak Activity reached was 164, 8 Watts. Mean exercise duration was 11.5minutes. Mean Maximal Heart Rate reached was 135 beats per minute. Before and after effort: PRU (reference range<235) was 124,5 and 112,8 (p=0,5) and 56,7 and 54,8 (p=0,8) respectively with Clopidrogrel and Prasugrel; ARU (reference range<550) was 433,2 and 398.7 (p=0,01).

In patients treated after an ACS, inhibitory effects of dual AP therapy are not modified during physical activity. The inhibitory effect of ASA seems even better immediately after a stress test. This is for a resumption of intense physical activity after six months.