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Current time:0:00Total duration:8:27

Video transcript

all right let's talk about hypertension and the first thing we have to do is understand the two main categories or types of hypertension that are out there so there are two types primary and this is actually also called the essential hypertension you might hear that word essential and secondary and I'll write that as a 2 and so the the way that this is divided up is that primary hypertension is caused by something indirect okay so what does that mean exactly so I'll give you some examples of what the indirect causes could be it could be something like smoking or it could be that someone has obesity or is obese or it could be that they have hyperlipidemia meaning they have lots of fats floating around in the blood or let's say they have diabetes that would be another cause or indirect cause of hypertension and these are all risk factors right that's another way of thinking about these things these are general risk factors for having hypertension and the other category would be something direct and once I write this down you'll start seeing the difference this would be something like kidney disease so let's say that I have a problem with my kidneys and they for some reason these are my kidneys they are holding on to far too much fluid than they should and that's because they're diseased and so they're holding onto too much fluid and they're causing my volume of blood to go up they're causing the volume to go up and the stroke volume is going up as well and if the stroke volume goes up you know that you know stroke volume is going to cause a higher blood pressure because they're directly related to each other very direct now would be one example another example could be let's say I have what's called an aortic coarctation so this is a very specific problem this would be if I have my say Hart is here and I have the aorta coming off here normally it should be nice and open the way I've drawn it but if you have a coarctation then you might have a pinching in of the vessel so it would be weird start looking like this it would look like that like a pinch and if you have a pinching in right there then you have increased resistance they have increased resistance and if you have increased resistance you know again resistance is going to relate back to pressure so if you have more resistance you have higher pressure so these are direct causes of hypertension which is slightly different than the indirect causes I wrote above there smoking obesity because there's no clear direct mechanism in any of those things they're just more general risk factors so this is how we kind of divvy up the two groups and we say okay if you have one or the other then you're in the primary or secondary group so let's figure out of the two which is more prevalent prevalent and this basically means which is gonna affect more people at any point in time so if I was to pull all people with hypertension ask them hey what group are you in primary or secondary most people would say primary because most of these people are going to be smokers or obese or diabetics or people that have hyperlipidemias and these risk factors that we just laid out in fact over ninety percent of the people have primary hypertension and only a few people are less than 10 percent are gonna say nope I'm actually in the secondary group I have a very specific reason for having hypertension so this is actually a very easy way of figuring out if people are having hypertension from an indirect cause or direct cause all right so now let's assume that you follow one person over time one individual and that person used to have normal blood pressure let's say this is blood pressure over here and I'm going to write it out mean arterial pressure ma P mean arterial pressure and we want to maintain a mean arterial pressure a map you know of a certain number so this would be like a normal blood pressure range right something below this dashed line so this is normal but of course you know many people have something higher than normal they over time might develop higher blood pressure so maybe they start out here and here you know in the normal range and then they start having high blood pressure and it kind of goes up and down and up and then down and stops there so in this person I'm going to connect the dots they if you ask them would not have any symptoms for most of the time they would actually say you know I feel fine I don't have any symptoms at all in fact up until this point in time they would say they have no symptoms no symptoms and the vast majority of people are actually in this group so most people with hypertension if you ask them if they have symptoms from it they would say no they don't have any symptoms but at some point they can develop symptoms not everybody but you can develop symptoms and when you do it's usually quite significant so you might have problems with your heart maybe your heart is having to work harder than it ever had to and you're having some heart failure or you might have problems with your large vessels or medium vessels and primarily these are the arteries right because the arteries are the are the vessels that are seeing those high pressures and those arteries might be getting very stiff or you might have problems with tiny vessels these are the little arteries the smallest ones or the arterioles and remember the smallest arteries and arterioles they're not sitting there naked in your body they're usually within an organ right so they're usually within the kidney or they could be within the eye so I'll just draw these two all right so they're usually within some other organ and if you have problems with the smallest arterioles let's say they're breaking then you really what you're saying is you're gonna have kidney problems or eye problems so these are the kind of problems you can get and because most people are having no symptoms most people are over here you really want to catch them before they cross over from no symptoms to having symptoms and you want to take care of the blood pressure problem so that they never develop any symptoms that's the goal now unfortunately some people develop what's called malignant hypertension and I'm gonna write out for you what malignant hypertension means it's a few things and we can actually even draw it on our figure maybe I'll do that so you have people with malignant hypertension that have a rapid rise in their blood pressure and it causes damage and to to the heart and vessels and finally the range that we're talking about it's a rapid rise to a really high blood pressure sometimes we think of these pressures being around 240 over 120 really high blood pressures so on our graph this could be the person that you know unlike the person in white this person maybe had a very quick rise in pressure and then it got very high maybe got up to 120 over or 1 to 40 over 120 and so this would be the third point the rapid rise is the first point and the fact that they're having symptoms is point number two so you can see now how someone with malignant hypertension could look on this sort of a graph