 What comes to nursing school explain in this video on collateral circulation? This is a term that many times we hear when we talk about coronary artery disease and the acute coronary syndrome and maybe even MI or myocardial infarction. Now in order to really understand this I've drawn out some pictures but first of all collateral circulation is the body's response to coronary artery occlusion. So when there is a blockage or a blockage that starts to build in one of the coronary arteries the body knows that this is not good for the perfusion and the oxygenation of the hard muscle itself. So over time it can build what's basically is a natural way to a coronary artery bypass. And so what happens is typically in normal blood flow we have our coronary arteries that gets fed by smaller blood vessels and then these kind of branch off, but the main blood flow is through this coronary artery. When there is a partial occlusion as we see in blue here the blood flow is diminished through the coronary artery because the coronary artery here is narrowed. And then what happens these extra blood vessels, the smaller vessels that we have on the side here they kind of grow together like tentacles. Imagine or remember from physiology class how kind of the dendrites of the neurons work. So these tentacles of these arteries they just kind of find each other and start to connect. So now because we can't put a hundred percent through the blood flow through here because we have this occlusion some of the blood flow will make its way through these arteries that have now connected to perfuse the distal part of the heart or the coronary artery. So there is decreased blood flow through the coronary artery and some bypassing and collateral circulation development. Now when there is a complete obstruction or occlusion when this blood vessel is completely clogged so no blood flow will go right through here through the center. These tentacles, these blood vessels that have grown together now build this extensive network so the blood flow can come from the top and run through all these side branches of the arteries right here to still perfuse this distal part of the heart. So in this case in a complete occlusion there is no blood flow through the main artery but all the all is bypassed by the collateral circulation so there's multiple different pathways that go through here so that we ensure that we have blood flow in the distal region. So this is something there's some contributing factors there is a term called hereditary angiogenesis angiomening blood vessel and then genesis the creation. So there is such a condition where the patient is more prone or through their genetics is more likely to build some more blood vessels but also if there is chronic ischemia and this occlusion starts to form very slowly so it's this takes years maybe even decades to come to this complete occlusion then the body has time to form this collateral circulation this network here that ensures the perfusion and so the longer the occlusion takes to form the higher the incidence of collateral circulation and then think about how much better it is for the patient because now they're not going to have acute coronary syndrome they might not be symptomatic with this occlusion because their body has taken care of it them and itself and this is also why we hear about maybe younger patients having poorer outcomes with a heart attack because they have not had this chronic ischemia this chronic partial occlusion that has eventually come to this complete occlusion so they don't have this collateral circulation so that's when you hear of the 40 50 year old having a heart attack and dying basically falling over and dying from that because their body has not had the time to develop this network of these arteries here to ensure the perfusion and so that if it takes longer for the occlusion to form the body has time to do that so many times we see collateral circulation in older patients and many times also in those that have chronic health conditions that make them more prone to coronary artery disease which are all the risk factors diabetes hyperlipidemia hypertension and all those things that that we know that contribute to coronary artery disease so thank you for watching this video on collateral circulation I hope it really has kind of helped you understand with the graph on what that is and what it really means and it's a beautiful mechanism that our bodies have developed that that we can actually ensure the perfusion of our cardiac muscle tissue by developing this collateral circulation please give me a thumbs up if you enjoyed the video and see you soon right here on nursing school explain thanks for watching