Why is aspirin used in myocardial infarction?

[sameeralord]

Hello,

I'm simply confused how effective is giving aspirin in various cardiac disorder? Ok someone develops severe chest pain, presents to hospital within 3 hours due to MI?Is there any use in giving aspirin. I know aspirin disaggregates platelets, and this is primary haemostasis. Now within 3 hours I believe primary haemostasis is already done, so is their any point in giving aspirin. What I'm basically asking is how long does primary and secondary haemostasis take and also let's say a full thrombus was formed then is the only choice to lyse it with streptokinase, or does aspirin have an effect even after a full thrombus is formed.Then having said all that and if they are only true only use I can see of aspirin is prophylaxis in cardiac disorders or very early MI. Thanks

 

[SW VandeCarr]

Hello,

I'm simply confused how effective is giving aspirin in various cardiac disorder? Ok someone develops severe chest pain, presents to hospital within 3 hours due to MI?Is there any use in giving aspirin. I know aspirin disaggregates platelets, and this is primary haemostasis. Now within 3 hours I believe primary haemostasis is already done, so is their any point in giving aspirin. What I'm basically asking is how long does primary and secondary haemostasis take and also let's say a full thrombus was formed then is the only choice to lyse it with streptokinase, or does aspirin have an effect even after a full thrombus is formed.Then having said all that and if they are only true only use I can see of aspirin is prophylaxis in cardiac disorders or very early MI. Thanks

Aspirin (ASA) has been shown to have a synergistic effect with a number of thrombolytic agents and is often used in combination with them in the ER/ICU unless there are contraindications. While there is an ideal time period for using such agents, the idea of a "full thrombus" doesn't apply in the acute situation. A thrombus may continue to extend under the right conditions. The real end point is evidence for reperfusion.

http://www.rcpals.com/downloads/fibrinoforACS72006.pdf

http://www.ncbi.nlm.nih.gov/pubmed/2108852

 

[mazinse]

you need to look up the protocols to treating MI, it gives a nice algorithms of what to do. Also unless you have been to a catheter lab you don know how much the coronaries are occluded

 

[SW VandeCarr]

Also unless you have been to a catheter lab you don know how much the coronaries are occluded

You need to distinguish between the use of antithrombotics/thrombolytics in the acute situation (MI in progress) and established occluded coronary arteries. In the latter case, mechanical dilatation and the placement of stents or bypass surgery may be indicated, but not the thrombolytic therapy that the OP asked about.

http://emedicine.medscape.com/article/161446-overview

Opening coronary arteries with PCI (see link) may be an option in the acute situation as well, usually if drug treatment fails.