Clopidogrel administration is commonly prescribed in patients undergoing percutaneous coronary intervention, in patients with previous stroke and in patients under chronic hemodialysis via fistulae. Patients with chronic renal failure present lower clopidogrel response compared to those with normal renal function. Ticagrelor is a new oral direct-acting antagonist, which provides greater platelet inhibition in both clopidogrel responders and non-responders. It has also been shown that in patients with chronic kidney disease (creatinine clearance <60 mL/min)ticagrelor achieved an absolute risk reduction of cardiovascular death, myocardial infarction, and stroke greater than that of patients with normal renal function. Clopidogrel resistant patients as assessed by VerifyNow P2Y12(Accumetrics)will be administered after informed consent ticagrelor 90 mg twice daily for 15 days. Platelet reactivity will be determined at the end of the treatment period. Bleeding events, major adverse cardiac events and any side effects until Day 15 will be reported in a descriptive manner.

Inclusion Criteria:

• Age≥18 years
• Chronic renal failure under haemodialysis
• Platelet reactivity under clopidogrel 75mgx1 ≥235 PRU
• Informed written consent

Exclusion Criteria:

• Recent (within 1 month) PCI or ACS
• Requirement for oral anticoagulant prior to the Day 14 visit
• PLTs<100.000 / μL), Hct <28%, Hct > 52% at randomization
• Increased risk of bradycardiac events.
• Severe uncontrolled chronic obstructive pulmonary disease
• Known severe hepatic impairment
• History of gastrointestinal bleeding, genitourinary bleeding or other site abnormal bleeding within the previous 6 months.
• Other bleeding diathesis, or considered by investigator to be at high risk for bleeding
• Concomitant therapy with a strong cytochrome P-450 3A inhibitor or inducer
• Recent (<6weeks)major surgery including CABG
• Recent (<6weeks)stroke or any prior intracranial bleeding