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Biology - myocardial infarction

how does high blood pressure lead directly to a myocardial infarction?
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Original post by bee2018
High blood pressure can damage your arteries and overtime it thickens even more to withstand that high pressure. Think about it this way - the aorta is quite thick and it needs to be because it's got to pump blood all the way around your body, and for this you need high pressure!
But too much pressure is bad because the aorta can only withstand so much. As a result, the high pressure over time can damages the aorta's interior lining. High blood pressure is usually due to a build up of cholesterol, and this narrows the lumen of these vessels due to an increase in fatty deposits.
When your aorta due to either it's thickened walls, narrow lumen or a combination of both - it becomes blocked. Blood cannot pass through and you get a heart attack - otherwise known as a myocardial infarction.
Go on YouTube and you'll find some nice animations on how exactly this works. I hope that helps.

This is not correct. Myocardial infarctions (MI) is caused by a thrombus causes by rupture of an atherosclerotic plaque in the coronary arteries.

Atherosclerosis occurs when the blood vessel lining (endothelium) is damaged. This allows LDL to enter the vessel wall where it is oxidised. Oxidised LDL is taken up by inflammatory cells (macrophages). This starts an inflammatory cascade leading to fatty plaques. These fatty plaques get bigger over time which narrows the lumen. Sometimes these plaques can rupture which triggers a blood clot to form causing myocardial infarctions (if in coronary arteries) or strokes (if in brain).

Hypertension not only damages blood vessels, allowing LDL to enter the vessel wall, but also causes systemic inflammation which increases oxidised LDL.
Neither type 1 nor type 2 myocardial infarction are directly caused by hypertension.

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