Antiplatelet Therapy in Secondary Prevention of Stroke

Sekundarna prevencija obuhvaća liječenje i rehabilitaciju bolesnika koji su preboljeli moždani udar ili tranzitornu ishemijsku ataku (TIA) te identificiranje i liječenje osoba s vrlo visokim rizikom od nastanka moždanog udara kako bi se on spriječio. Sekundarnom prevencijom može se produžiti ukupno preživljavanje, poboljšati kvaliteta života, smanjiti potreba za kirurškim zahvatima te smanjiti učestalost budućih moždanih udara i TIA-e. U sekundarnoj prevenciji ishemijskoga moždanog udara najčešće se od antiagregacijskih lijekova propisuje acetilsalicilna kiselina (ASK). Ona inhibira ciklooksigenazu i tako sprečava sintezu tromboksana A2 (TXA2) u trombocitima, ali i sintezu prostaciklina (PGI2) u endotelnim stanicama te tako smanjuje agregaciju trombocita i učestalost kardiovaskularnih i cerebrovaskularnih bolesti. Primjenom ASK prosječno se smanjuje relativni rizik od vaskularnih incidenata oko četvrtine (25%). ASK u svakoj dozi višoj od 50 mg/dan smanjuje rizik od moždanog udara, a više doze povezane su s povećanom učestalošću nuspojava ASK (krvarenje iz probavnog trakta, probavne smetnje, žgaravica, mučnina, povraćanje). Od svih antiagregacijskih lijekova dostupnih na tržištu najjeftiniji je ASK te je u sekundarnoj prevenciji moždanog udara najisplativiji. Međutim, antiagregacijsku terapiju treba prilagoditi svakomu pojedinom bolesniku.Secondary prevention includes treatment and rehabilitation of patients who have had a stroke or transient ischemic attack (TIA), and the identification and treatment of people at a very high risk for stroke. Secondary prevention may prolong the overall survival, improve the quality of life, and reduce the need for surgery and the incidence of recurrent stroke and TIA. In the secondary prevention of ischemic stroke, the most commonly prescribed antiplatelet drug is acetylsalicylic acid (ASA). ASA inhibits cyclooxygenase, thus preventing the synthesis of thromboxane A2 (TXA2) in platelets and that of prostacyclin (PGI2) in endothelial cells, and consequently lowers platelet aggregation and reduces the incidence of cardiovascular and cerebrovascular diseases. Therefore ASA reduces the average relative risk for vascular events by approximately 25%. ASA, administered in any dose greater than 50 mg/day, reduces the risk of stroke, while higher doses are associated with an increased incidence of ASA side-effects (gastrointestinal bleeding, indigestion, heartburn, nausea, vomiting). Out of all antiplatelet drugs available on the market, ASA is the least expensive and therefore the most cost effective drug in secondary prevention of stroke. However, antiplatelet therapy should be individualized for each patient