Heart Failure – Cardiology | Lecturio

[Music] welcome to lecture eight in the series introduction to cardiology in this series we are going to consider one of the most serious problems that faces a cardiologist the patient with heart failure heart failure is very common and increasingly common these days it's because it is a common complication of older individuals and of course the older population is increasing throughout North America and Western Europe as well as Asia heart failure is defined differently in different circumstances by different cardiologists but basically it's an inability of the heart to pump enough blood to meet the demands of the body in other words if one exercises one requires an increase in blood flow to the body and if you can't do that you may develop the symptoms of heart failure as we're going to see there are a number of compensatory mechanisms that get set off in heart failure and some of them actually work to increase symptoms in these patients the major issue here is that the heart has an inadequate or decreased cardiac output remember cardiac output that's stroke volume times heart rate that is the amount of blood the heart puts out each beat times the heart rate and in this setting what you see is that the patient has an increase in blood volume because of compensatory mechanisms that work to correct the heart failure state unfortunately this leads to fluid accumulation in the body and even edema that is swelling in the body this can also be associated with circulatory congestion for example in the lungs so you have increased fluid in the lungs so the patients are short of breath and in addition you may see patients being markedly fatigued because they're not getting adequate heart pumping as I said before it's a very common problem there are more than three million patients in the United States with heart failure there's a number of new patients presenting every year and unfortunately heart failure has a very poor prognosis often a prognosis just as bad as many forms of cancer heart failure is more common in african-americans and it's interesting that these patients seem to do better briefly in it when they're admitted to the hospital but their long-term outlook is worse some of this may be because of lower socioeconomic conditions in many African Americans the heart failure frequency in the US has been increasing with an increasing population a statistic I like to quote is that in the United States in every 24-hour period more people will become age 85 than will be born so you can imagine if heart failure is a very common problem in the elderly just as atrial fibrillation is a common problem the elderly both of these are what I call quote growth industries and again women tend to be a little less frequently affected by heart failure men is a little more common early on but once we get into the geriatric population above 65 to 70 the amount is about the same there are a number of factors that are referred to when we talk about heart failure and you'll remember some of these factors from the basic lectures on heart function remember preload preload is filling of the heart so that it's a manifestation of the size of the ventricle when it fills up when you have increased blood volume you increase the preload that is the amount of volume that the heart has to squeeze out this happens with some of the compensatory mechanisms that increase the blood volume and consequently preload may be increased in the heart and what increased preload leads to is increased filling pressures in the ventricle during diastole during the rest period this leads to increased pressures in the ventricle during diastole and those increased are transmitted back to the lungs and even back to the rest of the body leading to fluid accumulation in the tissues of the lung and the rest of the body afterload is the work of the heart it's the resistance the ventricle feels when it is pumping out this is usually due to resistance in the vascular system you'll remember that from the basic lecture in cardiology increased peripheral vascular resistance leads to increased afterload increased work of the heart you can imagine that's not good in heart failure and in fact here's a clue when we talk about therapy of heart failure one of the things is to decrease after load to decrease the work of the ventricle and hope that it will recover from its depressed state um there are two forms of heart failure systolic and diastolic in other words sometimes let's take diastolic first of the ventricle squeezes alright but it fails to relax normally it relaxes slowly or in a stiffened manner leading to increased pressure in there that gets transmitted throughout the circulation and leads to collection of fluid as we talked about before edema systolic heart failure is when the ventricle fails to squeeze well that can happen a course with the patient who's had heart attacks happens to patients with cardiomyopathy heart muscle disease and often systolic heart failure is associated also with diastolic so most patients with heart failure have both systolic and diastolic but there is a whole group of patients or minorities you can see from the circle diagram here who have pure diastolic heart failure interestingly the long-term prognosis for diastolic heart failure is just as bad as for systolic heart failure diastolic heart failure tends to occur in older individuals often with thickened heart muscle now there are a number of compensatory mechanisms that the body sets off when it sees heart failure remember I mentioned them just a few moments ago what are the compensatory mechanisms well let's think why would the body compensate for decrease cardiac output for decreased pumping of the blood the reason the body compensates is because it interprets heart failure as if there had been a hemorrhage a blood loss or dehydration in other words the reduced pumping ability the body interprets as oh there's a lack of blood from a hemorrhage or there's a lack of fluid into the circulation because of dehydration and it sets off a whole bunch of compensatory mechanisms aimed at holding on to fluid water and salt unfortunately this is exactly the opposite of what we would want because in holding on to fluid you actually create the setting where patients put some of that fluid into the tissues both in the legs as edema or in the lung as pulmonary edema so the activation of these of the neuro humoral system that is central nervous system initiated activity to correct the heart failure situation actually makes the situation worse these systems work great if there's dehydration you're caught in the desert without water they work great if there's a hemorrhage you've been cut somewhere or you're bleeding from an ulcer in your stomach but they work unfortunately in a negative manner in the patient with heart failure let's just talk for a moment about why these compensatory mechanisms work they work because of something I mentioned before starlings law the so-called rubber band law of the heart the more you fill it the more it contracts so what the compensatory mechanisms are trying to do is to increase the filling of the heart so it will squeeze more as I've said unfortunately that leads to elevated pressures that back up in the system and result in edema but the rubber band law of the heart says that the force of contraction is related to how much you stretch the heart muscle cells and this increases contractility so you see why the body is trying to increase the pumping ability of the heart and this works fine if it's a hemorrhage or dehydration but it doesn't work well when the patient has heart failure so remember stroke volume is the number of cubic centimeters that the heart puts out with each time it squeezes times heart rate that's cardiac output so when we have a reduction in stroke volume because the heart has been injured sometimes you'll even see the heart rate go up because the central nervous system says Oh cardiac output is falling we have to increase the heart rate we have to increase our ability to hold on to salt and water and increase the blood volume and use the Starling law to increase the contractility of the heart again unfortunately it's not the right setting for that and this leads to over filling of the circulation increased pressures in the circulation and increased fluid getting out into the lungs and into the tissues so the central factor in heart failure of course is depression of the heart muscle at least for systolic heart failure but also in diastolic heart failure the heart is supposed to actively relax and there's also depression of that but the communist form of heart failure as you've seen in the previous slide well it was systolic and it is usually because there's been some injury to the heart muscle most commonly from ischemic or coronary artery disease with heart attacks and again we've talked about the compensatory mechanisms here are the compensatory mechanisms listed first of all they're initiated by the central nervous system one of them is a signal that's sent to the kidneys and that the kidney actually does on its own the kidney is the regulator of the blood pressure in the body it sees a drop in blood pressure a drop in cardiac output and it releases compounds into something called the Rina angiotensin system which holds on to salt and water it's hormones that that actively tell the kidney hey don't don't pee out a sodium and water hold on to it because the circulatory system needs some volume there are also hormones that are released from the pituitary so called antidiuretic hormone we which tells the kidney hey hold on to water don't let the water go out in the urine in addition you also will have activation of the sympathetic nervous system which is part of the flight-or-fight system this sends adrenaline to the heart muscle to try and get it to contract more vigorously and it also clamps down a little bit on the periphery in an attempt to shrink the volume that the heart has to pump into all of these compensatory mechanisms you can see they work great if we're talking about dehydration or hemorrhage but they work in the wrong direction when the patient already has a depressed left ventricle the other thing that happens is that the heart muscle remodels it reconstructs itself if you will you can see in this diagram on the left the there's one form of remodeling left ventricular hypertrophy where the ventricle markedly thickens for example with aortic stenosis as we talked about with the patient in the last lecture on the other side is the sort of thing you see in a cardiomyopathy the heart dilates thickens a little bit but predominantly what it does is it dilates and you've all heard someone say oh so-and-so is in trouble they have a quote big heart that's because the heart's dilated that's often the final stage of heart failure when the heart has exhausted all of its other compensatory mechanisms to get the cardiac output up then you start to see this dilatation of the left ventricle now again we talked about the different kinds of heart failure systolic and diastolic but sometimes there are definitions based upon which ventricle is in the most trouble you most common is left-sided heart failure that's because the left ventricle has been injured but in some conditions such as severe lung disease with high pressures in the lung you may just see isolated right-sided heart failure so let's think about this for a moment with left-sided heart failure the backup is going to be into the lungs patients get flu in the lungs and they're short of breath so the edema is in the lungs with left-sided heart failure with right-sided heart failure the back-up is into the veins so you often see patients with fluid in the abdomen fluid in the in the legs so-called peripheral edema and the left ventricle may be working just fine but it's not getting any blood from the right ventricle because the right ventricle is failing and of course it's obvious what the left ventricle puts out depends on what the right ventricle puts out if they have to balance out if they don't balance out all the blood is going to end up on one side of the circulation or the other and then we've talked about before systolic heart failure failure of contraction diastolic heart failure failure of relaxation here's just a little diagram to remind you how the whole body is a coordinated system you see the brain is connected to the heart the brain is connected to the kidneys they're all connected to the peripheral blood vessels and as we've talked about when there's heart failure or when there's dehydration or when there's hemorrhage all of these factors become activated in an attempt to a restore the blood volume and B restore the pumping ability of the heart and here they are all listed again just as we've talked about before the central nervous system is critical sympathetic nervous system is activated the kidney through the real angiotensin system is activated and the ventricle is gets increased volume and therefore uses the Starling mechanism all of these things work together they work great if the patient's blood volume is down because of dehydration and hemorrhage they work against you when the problem is that the heart is not pumping enough and again here you see a diagram that just shows you how all of these interact how the decreased cardiac output can lead to lung congestion and how apper increased peripheral pressure can lead to peripheral edema the neuro hormonal activations through the kidney that go on all of these things are working in a complete circus motion like a horse riding around the the track and a circus around and around that they keep reinforcing each other and unfortunately in heart failure lead to marked retention of water and salt that leads to the various symptoms that the heart failure patient has in the American Heart Association guidelines talk about various levels of heart failure level a is somebody who's really predisposed to heart failure but has not developed it yet so that's somebody with high blood pressure diabetes hypercholesterolemia hyperlipidemia as we've talked about that leads to atherosclerosis heart failure hasn't developed yet but the substrate if you will is ready to go on and cause a heart condition that will lead to heart failure grade B is when you're starting to have some very early signs of heart failure by some of our fancy tests such as from the echocardiogram but the patient is still asymptomatic stage C is when the patient is already having symptoms they're tired they're short of breath they have peripheral edema and stage D is when they're really incapacitated with heart failure marked severe symptoms of heart failure now it's important to remember that heart failure relates to atherosclerosis in the majority of cases who present to the cardiologist with heart failure no surprise remember we talked about the last time I spoke to you about the typical patient that's the Communist patient that comes to the cardiologist the patient with atherosclerosis when that disease is advanced particularly if the patient has had previous myocardial infarcts or heart attacks the ventricular function is compromised and the patient shows up with heart failure so what are the risk factors for heart failure there the risk factors for a thorough Scottish heart disease there hypercholesterolemia hypertension cigarette smoking diabetes all the things we talked about before that can lead to atherosclerosis now and you can see that the Communists ones you know our problems leading to heart failure is ischemic heart disease but there's a number of other factors that are involved as well but ischemic heart disease the number one cause of death in the world number one cause of heart failure um there are a number of rarer causes of heart failure I'm not going to go into this in any detail but for example in the United States one of the commonest causes of cardiomyopathy is excessive alcohol intake alcohol is a poison for the myocardial taken in small amounts it's good increases the HDL level can be very pleasant in a social setting but excessive alcohol can lead to cardiomyopathy and of course a lot of other problems liver failure from cirrhosis etc etc um there are in other things that can cause heart failure we've talked about this before cardiomyopathy from a chronic viral infection certain drugs can do it um one of the favorite drugs for chemotherapy for breast cancer also damages the heart and some drug other drugs can do the same thing and of course arrhythmias with long standing fast heart rate that's uncontrolled can also lead to cardiac fatigue these things are much rarer remember ischemic heart disease is number one Public Enemy and here you just see all of the symptoms that patients will have with heart failure they will be dismiss there'll be shorter breath you will find maybe their lips are blue because they're not pumping enough oxygenated blood around there may be heart murmurs as we had in the patient in the last lecture with aortic stenosis sometimes on physical exam you will hear a loud extra heart sound that says the ventricles really hurting the patient's breathing fast you may hear actually sounds from fluid in the lungs and so forth there's a whole variety of physical findings that the doctor finds that confirms the diagnosis of heart failure remember from the last lecture the most important thing are the symptoms they give you the clue 90% of the answer of the diagnosis is in the history you then move to the physical exam oh yes I'm hearing things I'm seeing things that suggest that the reason the patient is tired the reason the patient is short of breath the reason the patient has swelling in their legs is because of heart failure right ventricular heart failure alone can cause a different set of symptoms and signs of course the edema the extra fluid is in the legs and you will remember that you may have problems in the abdomen because the increased venous pressure backing up is not only in the legs but it's also in the abdomen the liver swells so there's also swelling in the and fluid in the abdomen patients may find their their waist size gaining they become very very tired and often you can even feel on physical exam this bulging abdomen that's full of fluid remember again right heart failure much less common the left heart failure common has caused the left heart failure ischemic heart disease that is previous heart attacks so here's a few diagrams that just show you what the cardiologist sees when they see a patient usually with very clear and significant heart failure and you can see their pupils may be dilated from the from the adrenaline that's circulating the skin may be gray or pale or even blue cyanotic and a whole bunch of things they may be short of breath breathing fast they may be uncomfortable lying back and feel more comfortable breathing sitting up there may actually be sounds in the lungs from fluid in the lungs crackles or so called rowels they may have a cough from the excess fluid that's in their system there is often increased pressure in the veins and you can actually see that in the neck I'm going to show you a picture of that and the blood pressure may be decreased because the cardiac output is down and also the patient may even have some discomfort in the abdomen swelling and nausea and so forth and of course you may see bulging of the abdomen as I mentioned and edema that is swelling in the legs all of these are not seen necessarily in one patient but in individuals you may see a number of these findings and of course patients anxiety level is increased of course because they're short of breath one of the worst things that can happen to you is to be suffocated it activates anxiety and a huge way and again you may see the fact that the patient has decreased oxygen saturation often we can test that with a little finger thing or an ear thing to see that the oxygen level and the blood is going down the patient's in advanced heart failure may be confused particularly in elderly patients there may be as I'm going to show you a picture in a moment the jugular vein is distended because of high filling pressures in the right atrium transmitted back to the jugular vein there can if the patient's had a heart attack there may be chest discomfort in association with this of course the patient is markedly fatigued and you may hear the heart sounds that I mentioned before this extra heart sound a heart may be increased in rate and again you may feel a swelling of the liver or the spleen from the venous congestion that goes back there and of course there's decreased cardiac output if you measure that often with an echo and the pulse may be therefore weak the patient is often cool-cool the skin may be sweaty so here's a picture there's a lovely picture of a distended internal jugular vein you can see it rising up from just above the clavicle of the bone that's right here on the front of the chest and you can see rising up almost to the level of the jaw so this is a patient with quite advanced heart failure in this case it's a finding of right ventricular failure but the Communist cause of right ventricular failure is often left ventricular failure that increases pressure in the lungs increases the work of the right ventricle which eventually fails so this could be a patient with left ventricular and right ventricular failure or it could be somebody with isolated right ventricular failure and here we see an example of peripheral edema you can see you push into the soft tissue of the leg and you'll notice that the impression stays when you take your finger away so this is a patient with advanced peripheral edema it also looks to me like the skin does have its normal tone its normal color it looks grey and modeled and often this is because of decreased cardiac output so of course we're going to do some tests to confirm our clinical impression we've had the history oh this suggests heart failure the patient short of breath they have peripheral edema oh we listen to the heart and we hear on extra sound the s3 gallop okay we now pretty sure the patient has heart failure then we do a chest x-ray you can see the two examples here the one on that one side is normal and the one on the other side that shows an enlarged heart sometimes we will even see evidence of fluid in the lungs pretty obvious on this chest x-ray this is called pulmonary edema the left ventricle has failed significantly and what we see is fluid throughout the lungs and of course this patient is very short of breath they might be breathing at 30 or 40 times a minute normal is about 12 13 14 times a minute and they met you may actually hear gurgling from this fluid that's collecting in the small alveolar sacs in the lung and being transmitted into the into the bigger bronchial tubes now this can drop the oxygen saturation in the blood can lead to fatal arrhythmias and people can die from this and and this this is a medical emergency that requires urgent therapy and here as a chest x-ray showing a variety of findings of a little less serious heart failure one can see edema in the lymphatics so called curly lines one can see fluid collecting in the pleura of you can see in the little angle there where the heart meets the chest that there's a little sort of rounded area that's actually fluid in the pleural space the space that surrounds the the lungs there's a variety of other findings that the radiologists know will often call you up and say your patient has heart failure we often do an echocardiogram to see how bad of the heart failure is for example is it left ventricular is it right ventricular is it very advanced is the ejection fraction that is the percentage of blood squeezed out by the heart very low or is it only modestly reduced this is an echo car from a patient with a very advanced heart failure well left ventricle is markedly dilated we don't see the the film with it but I'm sure if we saw the film instead of the ventricle squeezing normally like this it's doing this hardly squeezing at all and you can see also and this echo the left ventricle is enlarged so this is a patient with long-standing heart failure so let's talk a little bit about a treatment clearly treatment goals are to reduce the edema to reduce the excess fluid volume and to make the patient much more comfortable and able to have full activity you'd also like to increase the pumping ability of the heart sometimes if it's for example in the patient we talked about in the last lecture somebody with aortic stenosis taking away the stenotic valve and putting in a good valve allows the ventricle to recover in other settings if it's due to severe ischemia lack of blood flow in the heart coronary bypass or angioplasty may improve the blood flow in the heart and may not always but may improve a function of the ventricle and again lead to resolution of symptoms and there's a variety of drugs that help increase the removal of fluid from the body for example diuretics that increase renal excretion of water and salt will reduce the excess volume of salt and water in the body and often lead to marked improvement in the symptoms patients with heart failure particularly new heart failure require hospitalization they require a number of tests to determine why they're in heart failure and they also require a number of drugs that are used to improve if possible the function of the heart and to decrease the work of the heart and to increase fluid and salt excretion and what you do this a step diagram is a complicated one I'm not anticipating that anybody needs to learn this right away but it shows you as the heart failure increases the aggressiveness of our therapy increases so in the beginning we use ace inhibitors that is they Veysel dilate the arterioles they decrease the blood pressure a bit and they decrease the work of the heart in the sense what we're trying to do is rest the heart make the hearts job the left ventricles job a little easier but as you go along there's a variety of other interventions that are used both improving blood flow for example with angioplasty we also use drugs that rest the heart a little bit by decreasing the heart rate beta-blockers and then eventually you may even progress to devices that increase the pumping ability of the heart while you're getting ready to do something more aggressive for example change of heart valve or even in the most severe stages do a heart transplant give the patient a new heart it's important that patients have lifestyle changes particularly with the milder forms of heart failure because what we're trying to do is prevent heart failure from progressing so what are those lifestyle changes clearly somebody who's obese you've got a lot of extra weight around if you have a big belly that has 40 or 50 pounds of extra weight it's like you're carrying a 40 or 50 pound knapsack on your back and you're asking the heart to do that extra work you can imagine that's a bad idea so dieting and reduction of obesity is important number 2 cutting back on salt because the more salt you take in the compensatory mechanisms of the body hold on to that salt and of course increase blood volume so restriction of salt it turns out that regular particularly in the beginning supervised exercise or physical activity actually improve the whole cardiovascular system and enable patients to do more work with the same cardiac output that they had before so and of course stopping things like cigarette smoking which are damaging to the blood vessels and which can cause acceleration of atherosclerosis just as in we talked about in patients with a heart attack or coronary artery disease there's a whole variety of lifestyle changes and often these are integrated between the cardiologist and the gu cardiac rehabilitation program and then there's a number of medications I talked about them briefly before let me describe them in just a little more detail we give beta blockers beta blockers block the effect of adrenaline on the heart and they decrease the heart rate no surprise you got a sick tired heart you don't want to keep it being having a very high heart rate you want to decrease the heart rate and actually sometimes the ventricle recovers when we get the heart rate which has been 90 down into the 60s or 70s - we can give ace inhibitors that's the angiotensin converting enzyme inhibitors what these do is they block the rina angiotensin system they decrease the constriction of blood vessels in the periphery drop the blood pressure a bit they also increase sodium and water excretion so you can see a they help by decreasing the work of the left ventricle a bit and B they help get rid of some of the excess salt and water diuretics I already mentioned they increase urine flow and consequently increase sodium and water excretion by the heart and of course you can see that there are also possibilities of increasing the squeeze of the heart it turns out that increasing the squeeze of the heart can sometimes overtax an already tired heart but at least one agent digitalis seems to be safe in critical situations where the patient is in shock that is they have a dangerously low blood pressure we give intravenous drugs for example intravenous adrenaline like drugs that increase the contractility of the heart but you can only do that for a short time because in a sense you're whipping a tired horse so maybe it runs a little faster for a short time but it dies sooner so we're very careful with the use of drugs that markedly increase the contraction of the heart in heart failure and again here you see all the drugs listed that can be used you can see the the beta blockers the ACE inhibitors the diuretics and then the inotropic agents on the far right are the ones we try to use as little as possible and again there are there's patient counseling we already talked about the lifestyle alcohol is a depressant on the heart so we want patients drinking as little as possible smoking has to stop we want weight control we want regular exercise all of the lifestyle things again repeated to work with the medicines we're giving or to work with the interventions for example opening up a coronary artery or replacing a heart valve and further patient counseling of course involves the medications are the patients taking the medications and are they taking them regularly and as appropriately prescribed this is a huge problem in the United States many patients fail to take their medications if there are surgical or catheter interventions what these contain and what they can do and what the potential complications are one wants to reduce stress in the patient's life one wants the patient to keep track of symptoms are they getting better are they getting worse is their weight gaining all of a sudden because of a marked increase in fluid retention and of course we would like patients to not over dull ghin fluid intake and certainly come for follow-up visits with the doctor or the nurse clinician in order for us to monitor how things are going with therapy and if we have to make further adjustments in therapy so in conclusion heart failure is a growth industry particularly in older individuals it's caused by many diseases but in particular by atherosclerosis are disease that causes damage to the left ventricle again leffen tricular systolic heart failure is the Communist the left ventricle doesn't squeeze as well and the Communist cause of that ischemic heart disease prevention of course is better than cure I don't have to tell you that and how do we prevent that by controlling a thorough Stratta Chris factors before they put the patient in the heart failure situation of course there's a whole variety of diagnostic tests that we use when the patient presents with heart failure but remember the clue is in the patient symptoms with confirmation by the exam and then we do some sophisticated tests to see what's the cause of the heart failure and how severe is the venturi Killer damage and then we introduced a whole variety of therapies both drugs and even some of the newer device therapies for example we can open up blood vessels and even in extreme cases we can take over with little pumps full of heart while we're trying to get it to respond and come back to normal and of course then we're going to have to do a lifestyle changes there's a new pacing protocol with a special pacemaker that can in some selected patients can improve the pumping of the heart all of these are fairly extreme things done right at the end and again we talked about the fact that there's a lot of Technology here but the best deal is to stop the heart failure before it starts with reduction in risk factors or identifying it early and getting all of those things including the lifestyle changes implemented before the patient progresses to a point that they need things like by ventricular pacing and heart-lung machines and so forth thank you for listening to this lecture I look forward to seeing you with the next one [Music]

Channel: Lecturio Medical

Views: 153,341

Rating: 4.9096541 out of 5

Keywords: Heart Failure, Heart Failure symptoms, heart failure diagnosis, Heart failure lecture, heart, Cardiology UMSLE

Id: eThrxyAobsQ

Length: 37min 2sec (2222 seconds)

Published: Mon Aug 06 2018