Question

do heart attacks occur only in the coronary artery

Answer 1

No, CAD (coronary arterey disease ) is only the Primary cause of Heart Attacks

Answer 2

so no other artery can cause heart attack

Answer 3

I think any artery can cause a Heart Attack if its blocked up

Answer 4

Heart attacks (correctly called cardiac infarcts) are caused by a paucity of perfusion or blood flow to the myocardium, the layer of muscle surrounding the heart. Basically, the cardiac muscles cells don't get enough oxygen, a condition called ischemia, so they die with obvious loss of function.

For that reason, only blockages in the coronary arteries - the ones which supply the myocardium - cause heart attacks.

Blockages, called thromboses, can and certainly do occur in all other arteries and veins. If that artery is the only source of blood in that tissue (often tissues have secondary blood supplies) then it certainly will result in general ischemia and infarcts. If you get a blood clot in the arteries which supply the lungs, it is called a pulmonary embolism; if you get a blood clot in your legs, like people sitting too long on airplanes, it is called a deep vein thrombosis or DVT; you can get them in the cerebral arteries where they cause strokes...

Answer 5

I should say that the term thrombosis refers specifically to blockages due to blood clots. More generally, blockages can be caused by all sorts of other things...

Answer 6

when you form a plaque does form along the entire artery or only a part of the artery?

Answer 7

Plaque - as seen in diseases like atherosclerosis - is a build up along the arterial walls in general. Think of a plumbing pipe with rust or dirt slowly building up inside it. Sometimes, the fluid pressure of blood against the plaque tears part of it off and it then sticks somewhere and blocks blood flow at a specific point.

The technical answer is that the plaque doesn't build up evenly on the walls of most arteries. It tends to build up thickest in places where the artery is under the most fluid pressure, which is why high blood pressure is such a risk factor for development of atherosclerosis.

Answer 8

Heart attacks can be caused by blockages due to other things in the vessels: blood clots form when they shouldn't and get stuck. Some researchers have found that blood clots form over and around plaques, so plaques are a risk factor for heart attacks too.

Other times, like in vegetative endocarditis, growths inside the circulatory system tear off and block smaller arteries, too.

Answer 9

so it builds up usually in thickest regions of the artery?

Answer 10

No, plaque builds up in parts of the artery which are under the most fluid pressure from the blood.

Answer 11

how would you know which region
is under the most pressure

Answer 12

Consider blood as it leaves the heart. It is under a lot of pressure because it is really close to the pump which is pushing the rest of the blood through the circulatory system, and on the other side it has all that blood on the circulatory system sort of pushing back on it.

It enters a big thick artery called the ascending aorta and goes up toward your shoulders for an inch or so, then your aorta hooks a U turn in a structure called the aortic arch and descends through your chest and abdomen to supply arteries in there. As it makes that turn, the top of the aortic arch is under a lot more fluid pressure than the bottom of the arch.

Why plaques form differentially in high pressure areas is not really understood. There are a couple theories.

As all those little blood cells and fluid molecules hit the top of the arch and start to turn, they scrape against the cells which line it and damage them. This activates the clotting cascade and little clots adhere to the vessel wall and provide the substrate for plaque formation.

Other people think that the distribution of cells in the artery walls differ according to how much pressure the tissue is under. They contain more elastin fibers and a thicker sheaf of muscle; somehow, these cells are better suited to formation of plaques.

Answer 13

Closely related to blood pressure is an idea of "sheer forces." Pressure pushes outward on vessel walls; sheer forces are blood cells and fluid dragging along on the surface of the vessel walls in the same direction.

Answer 14

do you know what a thrombus( is it when blood clots around the plaque)

Answer 15

Yes, I know what a thrombus is: it is when blood clots either around itself or around any foreign body in circulation...

Answer 16

so when plaque breaks off in an artery blood clots around it forming a thrombus. eventually the thrombus completely blocks the flow of blood. cutting off blood supply to heart leading to a heart attack

Answer 17

That certainly could happen. It'll only cause a heart attack if it lodges in one of the coronary arteries which supplies the heart. If it lodges in some other artery which supplies blood to a different organ, it'll cause ischemic injury or an infarct there.

And not all blockages are caused by blood clots and plaques (although most are). Any foreign object which shouldn't be in circulation but is can cause blockages of pretty much any artery, depending on the object's size and the artery's size.

Answer 18

the thrombus moves until it gets stuck

Answer 19

Yup.

Answer 20

so what if a blood clot occur in another artery on the heart what is called

Answer 21

The blood clot itself usually forms in a different artery. Often times, they actually form in the veins because the blood pressure in veins is much lower. They get carried into the heart - not the arteries around the heart, but into the pumping chambers themselves - and then through the pulmonary circulation. If they lodge in the lungs, they are called pulmonary emboli. After that, they get pumped back through the heart and into the systematic circulation.

Then they are named for where ever they lodge. If they stick in a tissue which has another blood supply, the reduced total blood flow will produce a condition called ischemia. If they lodge in a tissue with only that artery, it will cause a much more severe oxygen deficit which results in a condition called an infarct.

So for example, if they lodge in a coronary artery, they will cause cardiac infarcts or heart attacks.

Clear?

Answer 22

you are so knowledgeable thank you so much!!!

Answer 23

You're very welcome.

Answer 24

heart attack if its blocked up