in this video I will simplify heart failure so that you feel better prepared for USMLE and comlex as a brief overview heart failure refers to a dysfunction in the heart's ability to pump we know that the heart pumps blood I'm talking to you now like you're in seventh grade if the heart can't pump because of heart failure where will that blood go depending on where that blood will go and more specifically depending on which side of the heart can't pump that will help you figure out what symptoms you will see and what findings you will see in life and on your exam now some terminology to go over here first sometimes the the term congestive heart failure is used congestive heart failure is heart failure plus fluid overload and because in many of the cases that you'll see on your exam are going to have symptoms of fluid overload yes you are dealing with heart failure and more specifically yes you are dealing with congestive heart failure now there are some terms you might see when you go on your clinical rotations this is less important for step one and level one but I'll put it here for completeness sake hfref is heart failure with reduced that's the r ejection fraction historically this was referred to as systolic dysfunction but it has been renamed hfref because of the reduced ejection fraction hfp F the P stands for preserved that is heart failure with preserved ejection fraction and the terminology was changed because it's not only systolic or only diastolic dysfunction often times heart failure has elements of both and so the more scientifically correct terminology is to talk about the change in ejection fraction whether it's reduced or whether it's preserved but as far as step one and level one are concerned the best way to understand heart failure is to separated it into left and right heart failure so let's start with left-sided heart failure so in left-sided heart failure the left ventricle is unable to maintain ejection fraction to keep Pace with the incoming blood supply from the pulmonary circulation because the left heart and specifically the left ventricle can't pump blood out that blood is going to back up and congest the pulmonary system so all of your findings of left-sided heart failure will manifest as pulmonary symptoms so the patient is going to have very prominent shortness of breath that is caused by increased pulmonary capillary hydrostatic pressure again because left ventricle can't squeeze blood out blood has nowhere to go blood backs up in the pulmonary vasculature the key symptoms of left-sided heart failure are orthopnea paroxysmal nocturnal Al dnia and pulmonary edema orthopnea refers to shortness of breath when the patient is supine What's Happening Here is that because you lose the effect of gravity when supine blood redistributes to the pulmonary vasculature when that happens because you have left-sided heart failure the heart has nowhere to pump that blood that makes the patient feel short of breath paroxysmal nocturnal dmia is related and this is just shortness of breath that awakens one from sleep there's going to be an increased work of breathing when the patient is sleeping again because of that redistribution and when it wakes the patient up from sleep that is turned paroxysmal nocturnal dmia and lastly of course also related to the first two symptoms pulmonary edema that just refers to pulmonary Venus distension a key finding here that you could see as a buzzword on your exam is hemosin Laden macro fases and let's talk briefly about what those look like and how that works because this is pretty high yield so you have left-sided heart failure and that causes increased Alvar capillary pressure because there's increased Alvar capillary pressure red blood cells will leak out when they otherwise shouldn't the body's response to the red blood cell leakage is to have the macroasia essentially engulf those excess red blood cells and when a macras engulfs a red blood cell it's going to pick up the hemosiderin that was in that red blood cell and so if you look under a microscope you see what are termed heart failure cells which is just a macras that is Laden with hemosin meaning that there's lots of hemosin inside of it because it ate something in this case a leaking red blood cell in the capillaries uh in the in the alviola capillaries that shouldn't have leaked out but did and so when it eats it it's obviously going to take on the appearance of hemosin because hemosin is in your red blood cells so if you see this image this is termed a heart failure cell in this image the white arrow is pointing to the heart failure cell and if you see this it's suggestive of left-sided heart failure or heart failure in general so that's left-sided heart failure again big takeaway here is that because the dysfunction is in the left ventricle blood's not being ejected where does that blood go and what kind of issues does it cause well it backs up into the pulmonary vasculature so the patient has different findings and different sequele of shortness of breath now something that's really important to know for your test is pulmonary capillary wedge pressure or pcwp pulmonary capillary wedge pressure essentially is a surrogate of left atrial pressure the reason that this is called a wedge pressure is because they literally put a catheter they wedge Edge it into the pulmonary vasculature and they measure the pressure in there normally this should be between about 4 and 12 don't worry about the values if you're taking step one or level one they have to give you normal ranges if we have an increase in pulmonary capillary wedge pressure this suggests that there's a problem with left ventricular output because if blood was able to be ejected normally this pressure wouldn't be elevated but when you have left-sided heart failure and it backs up and puts a essentially distal resistance on the pulmonary vasculature the pulmonary capillary wedge pressures increased so let's simplify this and I'm going to make this as stupid as simple as possible so that your brain understands what pcwp means so normally blood will flow from right atrium to right ventricle to lungs to left atrium to left ventricle and out in left-sided heart failure the left ventricle cannot pump blood so blood fills up in the left ventricle the left atrium and then it backs up into the pulmonary system when this happens if you were to wedge a catheter right a wedge pressure if you were to wedge a catheter into the lungs your pulmonary capillary wedge pressure would be elevated again left ventricle can't squeeze pressures up in the lungs let's contrast that to a situation when you might have normal pulmonary capillary wedge pressure like in right-sided heart failure so in right-sided heart failure if the right ventricle can't pump out blood that backs up where's that fluid going to go well in this case not in the lungs so a wedged catheter in the pulmonary system might show a normal pulmonary capillary wedge pressure lastly understand that pulmonary capillary wedge pressure changes depending on different types of shock and I have a dedicated video on my channel to the different types of shock but just briefly because we're talking about it if you see an elevated pulmonary capillary wedge pressure you want to think cardiogenic or obstructive shock pulmonary capillary wedge pressure that's elevated with critically low blood pressure that's telling you that the patient has cardiogenic shock so that's something that's very important to know now all of that has to do with left-sided heart failure again left ventricle not squeezing blood where's the blood sitting in the left side of the heart where is pressure building up in the pulmonary system let's talk about right sided heart failure something that attendings love to pimp medical students on is that the most common cause of right-sided heart failure is left-sided heart failure so I've been repeating myself throughout this video but let's take this one step further left side of the heart can't pump where does blood back up the left ventricle it can't Pump It Out goes into the pulmonary system and going one step further back into the right ventrical so the most common cause of right-sided heart failure is left-sided heart failure left goes first that causes pulmonary symptoms then the right-sided goes isolated right heart failure of a pulmonary ideology meaning that it's due to a problem inherent to the lungs and has nothing to do with the heart itself that is termed core pulmonal symptoms of right-sided heart failure are going to be systemic so again on the left side your symptoms were shortness of breath and Pulmonary issues because blood was backing up into the pulmonary system if the right side of your heart can't pump blood out where does that blood back up well that's going to go into inputs into the right side of the heart so into the Venus system into the systemic circulation the liver the spleen peripherally if blood is not being pumped on the right side of the heart which receives Venus return that blood will be distributed systemically so what you will see is hipat spin omegal which is is due to increased portal resistance jugular Venus distension which is due to the increased Central Venus pressure and something to note here is that it has to be greater than 3 cm above the sternal angle and I have a picture so just hang tight and peripheral edema again because of this increased hydrostatic pressure and fluid transmutation peripherally so here's an image of jugular Venus distension in order for it to technically be jvd it's got to be greater than 3 cm above the sternal angle which I have on this slide here so just make sure you see a measurement of four or greater that's jvd now let's talk briefly about core pulmonal now this quite literally translates to pulmonary heart and again this is when there is an inherent pulmonary disease so like patient has severe COPD um patient has some type of pulmonary issue which causes pulmonary hypertension which can lead to heart failure secondary to that pulmonary issue so on your exam if you have core pulmonal you're going to see right-sided heart failure and you're going to see pulmonary hypertension couple high yield things to know here one is that in pulmonary hypertension you're going to have increased endothelin one which is a vasoconstrictor and decreased nitric oxide synthese which is a vasod dilator so should make a little bit sense here because we're dealing with pulmonary hypertension so we're going to have increased levels of vasoconstrictors and decreased levels of vasod dilators you're additionally going to see a loud P2 sound which the P2 sound is the pulmonic vve closing the reason that this is loud in pulmonary hypertension is because you have all of this distal resistance past the pulmonic valve so instead of the pulmonic valve closing normally or in a relatively soft manner it snaps shut it slams shut there's a lot of distal resistance and so it can't close normally that's going to be a very accentuated sound so if the P2 is loud and especially if you see tricuspid regurgitation you want to think about pulmonary hypertension and core pulmonal the last thing to talk about in this video as it pertains to heart failure is your S3 Gallop now this is a finding that you're going to probably see if you have an exam question about heart failure the S3 Gallop is a low pitch sound that occurs in early diaso at the end of the rapid ventricular diastolic filling phase what the S3 Gallop represents is ventricular overload this is a little bit controversial but we think that this is due to blood reverberating on the walls of The ventricle after the atrial flow because the heart has failed and because your the patient is unable to eject that blood out that increased volume reverberating on the walls of The ventricle and some scientists think that this has to do with the wall of The ventricle maybe even pushing against the chest creates an abnormal S3 Gallop now as far as where you can hear this sound this is best appreciated at the cardiac Apex with a patient lying left lateral decubitus so on your exam if they give you that 3D image of a patient make sure that you put it at the C put the you know the digital stethoscope that you control at the cardiac Apex to see if you hear an S3 Gallop but this would be present in a patient with heart failure so takeway of this entire video is that if you have shortness of breath evidence of of Venus overload jvd S3 Gallop you want to think about heart failure and separating that heart failure into left-sided versus right-sided can help your brain conceptualize what types of symptoms you should expect to see I hope that this was helpful to you best of luck