DIP Episode 288 - The USMLEs and Stress Tests/TEEs

Okay, welcome. My name is Divine. This is episode 288 of the Divine intervention podcasts. And in this podcast I'm going to be talking about stress tests and T Es. These are classic things that pop up quite a bit on MBME exams. This should be a relatively short podcast because there are some just higher things I want to hit on. But this is just one of those things you can almost promise yourself. You'll find it being tested in some way, shape of almost on step 2, secure on step 3. So I'd encourage you to pay attention to this. Take good quality notes and then go from there. And again, as a reminder, I'll be offering the comprehensive 16 and a half hour step 2, see key course and the MBME test against strategy scores. Both of those courses hold the MBME test against strategy scores holds on the 24th of March. And then the 16 and a half hour step 2, see key course holds across the 25th to the 27th of March. So just five and a half hours each day for the comprehensive 2, see key course. And then it's 2 and a half hours for the testing and strategy scores. For the test against strategy scores, we basically have a bunch of questions that are written. And we'll use those to review MBME test against strategies. Again, it'll be a very systematic fashion. By the end, you should be very well versed in the classic mistakes that people make on these exams and how to avoid them, how to read questions, predominantly how to know for for MBME traps.

And then for the comprehensive course, we cover everything. Right? So we cover and the comprehensive course, I will say is useful for sure, people taking step 2, see key and for sure people taking step 3. We cover peeds, surgery, OB guy, internal medicine, neuro, psych, bio stats, ethics, quality and safety. And all those things that were changed in starting in November 2020, we cover all of those in great detail. Again, I have one in the original of the class and the people that attended found it to be extremely helpful. So if that's something I'm interested in, reach out to me and I'll be happy to point you point in the right direction. Okay, just should be an email through the website and I'll give you some more details on costs and what we do. But the course is a health over Zoom. And again, for those of you that are taking the newer MBME exam, some telling you, it will definitely be for your best benefit. It will definitely be for your best benefit is very thorough, very comprehensive. We cover a ton, we cover probably about 1200 concepts across the three days. So, okay. So let's jump right into it. Right? So let's talk about these stress tests. So the thing is, many people I feel unfortunately have a warped on the standing of water stress test constitutes the thing is stress tests. If you divide it into two category into two major goals, you're trying to accomplish your being good shape. Right?

So the thing is these stress tests, there are two major things you try to do. One day is going to be a method of stress. And then two, there's going to be a method of imaging. Right? I'll say that again, there's going to be a method of stress and there's going to be a method of imaging. The method of stress is different. The method of imaging is different. So you stress the heart to see if you can induce a skin by performing certain maneuvers. And then you then image the heart in some way as a target for all because it's not enough to just try to induce a skin. You need to be able to capture that ischemia. So you know that ischemia ischemia actually exists. Right? So what are the methods of stress? Well, the first one is doburemi. Right? Although, maybe I should talk about exercise first. Let's talk about exercise first. The thing is an exercise based stress test is the one you should always speak if there are no contraindications to exercise. This is the first line method of stress. Again, the fact that is the first line method of stress, again, doesn't mean that all an e kg must always be what you do alongside no. Okay? That's why again, you need to parse the stress test into two things. There's a method of stress and there is a method of image in. Okay? So the first line modality for stressing a person is exercise. Right? It's exercise. Many times they call this the burst protocol. You basically try to see if you can get to 85% of the persons that target heart rigged.

Right? So it's what you should always go with if there are no contraindications to exercise. Right? So the contraindications to exercise would be like if the person has like severe peripheral atrial disease or the person has severe peripheral atrial disease or the person has severe peripheral atrial disease. So the first line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line. So the second line is the first line.

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You don't want to be giving them Dubitamin. Because again, being a beta one eigenest, it increases cardiac output, right? It increases heart rate, it increases stroke volume. So all these things can raise the presence blood pressure and more. If a person's blood pressure is like one 90 over one 10 at baseline, then you give them Dubitamin. You're getting your blood pressure into the 200s. That's not very pretty. You don't want them getting like a stroke or something during the study. They'll probably be bad. And then the other one is if the person has a very nasty attack here, right? If the person has like WPW, that is especially like it's symptomatic. Or they have those here as a baseline. You don't want to go ahead and give those people Dubitamin because they get equal worsening. Those are the right. And then if a person has an acute coronary syndrome, especially on stable antenna, it should also not be giving them Dubitamin, right? Because again, you don't want to be increasing the myocardial oxygen demand. In a person that already has, because when a person is in unstable antenna territory, chances are the coronary stenosis is more than 90%. So you don't want to be doing that under those circumstances. Because again, if you increase myocardial oxygen demand, you can throw those people into a full blown M.I. Because again, remember M.I. is a rise from a supply demand issue, right?

So if you increase the demand, right, for blood, but there's nothing happening to the supply because the person has coronary disease, then the person can be thrown into an M.I. Even if they don't have like full blown obstruction. And then another reason why you should maybe not do a Dubitamin stress test, again, as a method of stress, is if the person has a cardiac condition that predisposes them to syncopy, right? A cardiac condition that predisposes them to syncopy. So what in the world do I mean by this? Well, think about the genetic disease athlete collapses on the field, right? hypertrophic cardiomyopathy. Those people, they shouldn't do a Dubitamin stress test, right? And again, the newer M.B.M.E. is, right, they can give you these scenarios where you're like, wait, I thought? Because the thing is, many people think the M.B.M.E. for some reason you just invent new concepts to test. That's not really true, right? It's the same concepts that, well, you know, the new stuff is the stuff from November 2020, which again, I've made tons of podcasts for, right? You can all find those on the website. But really, like, I know that thing is just, they can give you these, like, they're just finding, you know, usually is to test the same things that you've known before. So like, if a person has a HCM, you don't want to give them something that stresses out their heart, right?

Because if their heart rates, their contractivity increases, they're worsening that live-entry cloud flow track obstruction that is caused by systolic motion of the anterior microvolve leaflet and deconsyncopies. If you see an older person with a histroviatic stenosis, again, you don't want to do a Dubitamin-based stress test because again, those people can collapse and, you know, probably like die during the course of the study and that will not be ideal. Now, the next method of stress, right, is viso-dialiter stress. So the thing is, these viso-dialiter, they work based on the coronary steel principle, right? So let's look at two blood vessels, right? A and B. So let's say A is 95% stenosed and B has stenosis, right? These are both coronary arteries. Now, the thing is, A, the stenose vessel, the heart has this unique adaptation. The coronary vessels have this unique adaptation when there's stenosis distal to that stenosis. That coronary vessel dilates maximally, right? I mean, you can't dilate forever if you dilate, dilate, dilate, right? You pop the vessel, which you don't want. So it dilates maximally until it hits its maximum dilation. So it's always maximally dilated, right? So that means if you give a viso-dialiter, it can't dilate any further, if not the vessel pop. But coronary vessels will be the one without stenosis because it doesn't have any stenosis. It's not maximally dilated, so it has the ability to respond to the administration of a viso-dialiter.

So if, for example, you administer a viso-dialiter, and these viso-dialitres can be drug like adenosine, right? Or diperidomol or regadenosin, right? Regadenosin is R-E-G-A-D-O-N-O-S-O-N. Remember, regadenosin is a derivative of adenosine, probably a little more expensive if I'm not mistaken. But basically, like these drugs are viso-dialitres. So if you give that viso-dialiter, well, the sub-e, the hasmost stenosis is going to dilate because a viso-dialiter is around as it's supposed to. But vessel A will not, right? vessel A will not because it's maximally dilated. It can't dilate any further, so it doesn't pop. So because vessel B is dilated, if the same fixed amount of blood is coming to those two vessels, well, some extra blood will be shunted through B. Because B has more room to receive blood compared to A. So let's see, normally A and D together, they have this common source artery that delivers 500 meals to artery A and 500 meals to artery B. Well, if that one liter of blood total comes through that source vessel, because viso-dialiter may get 800 meals and then 200 meals will go to vessel A. If 200 meals gets to go to vessel A, that region of the heart that vessel A supplies would then be like, I'm not seeing enough oxygen. What's going on here? You'll stop freaking out the person will have chest pain, right? Person will have his skin exempt. Right? So that's the coronary steel principle.

The liter is still in blood blood from a coronary artery because that stenosis, you're still in blood from a stenosis coronary artery because the stenosis coronary artery has no ability to dilate. It's maximally dilated, distal to occlusion. Okay. Right? So the thing is, again, I don't know if you remember, it causes hyperpolarization. So if you hyperpolarize stents, especially smoke muscles, they're going to relax. Remember, hyperpolarization means you're making potassium escape from the cell. If potassium escapes, the smoke muscle cells will relax and get viso-dialition. Diperidomol. We know that diperidomol is a phosphodiesterase inhibitor. Again, the reason you may see me going over some basic science details in some of these step to seek is the three targeted podcasts. Is that your friends at the end of the year may be getting smart. Again, you know this exam is becoming, step one is becoming pass-field in a few months here. So some of these step one details are slowly beginning to shift to step to seek a and step three. I mean, step three for sure. They ask a ton of pharmacological questions. I can tell you this from experience and from tutoring tons of people that have taken said exam. So essentially, like diperidomol, it's a viso-dialiter in one of two ways. So one is, it's a phosphodiesterase inhibitor. So by inhibiting phosphodiesterase, it's going to increase your levels of cyclic AMP. When cyclic AMP is high in smoke muscle, it causes it to relax.

When it relaxes, it dilates. So you have smoke muscle relaxation with diperidomol. So it's a viso-dialiter in that regard. So it dilates the coronary vessels. Another thing is diperidomol is also an adenosine diaminase inhibitor. So by inhibiting adenosine diaminase, adenosine is going to build up. And then you're going to get that hyperpolarization and you're going to get that viso-dialition. And then like I said, regadenocene is an adenosine analog. So what are some reasons? What are some key things to know about these viso-dialiters? Well, the thing is, again, you can use them when the pressing cannot exercise. When exercise as the method of stress is not indicated. Now, what are some contraindications? Again, these ones are especially high autonome for the USML As. So the thing is, these things are very bronchoconstructive. They are very bronchospastic. So the thing is, if a person has really bad reactive airway disease, let's say they have really bad asthma, really bad COPD, they really shouldn't be taking these medications. Theophilin. Theophilin basically antagonizes the actions of adenosine. So if a person is on theophilin, and they should not be doing this particular test, or they need to stop the theophilin for a while before they do these. Viso-dialitobies, the stress methods. Remember adenosine, slows conduction down the evening.

So if a person has really bad IV block, like a 30-degree IV block, or a morbid stool, for example, then they should not be getting this test. And remember, again, caffeine actually antagonizes the actions of adenosine. So you are feeling interested to tell your patients to not have coffee or tea for about a day before these adenosine-based stress tests are done. Right? Now, one floorily high yield thing to know that I can almost promise you probably will not find anywhere is that in general, if a person has a left bondo branch block, I'll say it again, if a person has a left bondo branch block, the method of stress that is preferred, that is first line in these people, is this viso-dialitobies stress testing. Right? If a person has a left bondo branch block, do not give them dubido-mean, do not have them do any kind of exercise. Well, why is that? The reason behind that is, the way I think of it is, dubido-mean activates the heart, activates the heart's electricity for you to get contraction on all those things. Exercise, right? Your sympathetic nervous system comes into gear, activates the heart's electricity, and then the heart contracts.

The thing is, because these are versus a viso-dialitob that just relaxes the coronary vessels, the thing is, electricity may actually skew your results, because these electricity-based methods, if you may, may actually skew your results, because the thing is, you need to again activate the heart's electric activity, electrical activity, right, with all these methods. But viso-dialitobies, again, they are less dependent on the heart's electrical activity, because in the repression has a left-wound dubido-branch block. Remember, it may take some time for the signals to be translated from the left-eatrum to the left ventricle, right, or from the AV notes to the left ventricle. So, because there is a delay in signal transmission, it may lead you to believe that a certain region of the heart is a schematic, when it's not, where it's just like, you know, the signal is still coming through, it's just taking a long while to come through. So, if you see a prisoner has a left-wound dubido-branch block, you want to pick a method of stress that involves a denocene or diperidomol, or a regadenoset, right? And then, what are the methods of imaging? This one should be a much easier discussion. EKG, right, is a classic one that's used. But again, if a person has a baseline of nomality in the EKG, right, let's say they have like a left-wound dubranch block, or they have like 11 trucolide per trophy, right?

Or they have like some kind of STD pressure on this line, then it can make your studies very non-diagnostic, right? So, if a person has a baseline EKG abnormality, don't select an EKG-B stress test. The next one that can be used as the method of imaging is an echocardiogram, right? Again, if a person has a baseline EKG abnormality, you can do an EKG stress test. The thing is, if you're trying to evaluate for like, vovele data, you're trying to evaluate for one motion abnormalities, then, classically, namely, an exam, so an EKG is a pretty great idea to use in those circumstances. And then, the third thing is a nuclear medicine-based test, right? So, usually on imbim exams, they can call this a phallium, THA-W-L-I-U-M, phallium's integrity, right? So, this one is great, right? Basically, if you see like a radio nucleic mentioned in the Q-step, or in an answer choice, it's the nuclear medicine-based stress test. So, what are some contraindications to this? Well, if the person should not be getting a radiation exposure, because you're literally getting a radiation, although it's extremely minimal, it's pretty much safe. So, like, if a person is pregnant from the getting a stress test, you should not be the swan, right? Or if a kid is getting a stress test, they should probably not be the swan either, right? And also, if a person has like very large breasts, right? Like a lot of breast tissue, they should also be getting this particular stress test, right?

Because again, that can cause a lot of artifacts. That's one thing that is pain in radiology, right? And it does say a lot of radiology boards, just different artifacts, how you minimize them on all those things. But this is not a radiology podcast. So, last thing I will just say here is, many people have had this question for many many students, like, divine, when do I choose TEE as the answer on MB-Mexams? When do I choose TEE as the answer on MB-Mexams? Because, you know, TEE, transistophagealical cardiography, is different from TEE transthoracic echocardiography. Obviously, TEE is better because, you know, you put the ultrasound probe in the esophagus, and the esophagus is like really put just behind the left-eat room. So, you get much better views of the heart. It's a little more sensitive in those respects. So, let me tell you this. There are four scenarios on MB-Mexams where you always go to TEE over a TEE. Okay? And sometimes your friends at the MB-Mex will put both as answer choices, just to mess with your head. Pick the TEE. So, let me explain the first one. Is, if the person has endocraditis. If the person has endocraditis, you're trying to pick an echocardiographic method, always go to TEE. Second one. If the person you suspect they have a thrombus in the left-eat room, right? It doesn't matter. Always go to TEE.

I mean, literally, you're putting the ultrasound probe in a region of the body, the esophagus, that's what is called transness of a geolachocardiography. That is right posterior to the, it's like really right behind the left-eat room, right? So, you get much better image in that way. Right? And then, the next one is, if the person has some kind of prosthetic valve, anything, right? If you ever worry that, oh, this prosthetic valve, this person has, it's not working right. Just always do a TEE. It's the best modality in those circumstances. And then, the last one is, if a person has like really body, or a disease, right? So, let's say like, your dig-dyssection. Remember, when people have a dig-dyssection, and they have a more dynamically unstable, typically the smart thing to do for those folks is actually to go ahead and do a TEE. Right? So, the mnemonic eye remember is, I use the term, LPA. E-L-P-A, right? So, E for endocratitis, L for left-eatral thrombus, P for prosthetic valve issues, and then, if we're a dig-dyssees, especially a dig-dyssection, right? Especially a dig-dyssection. So, I think if you know these things, you should be able to get these TEE and stress-desk questions, right? So, as I wrap up, please don't forget to subscribe to the You Tube channel. Divine intervention, you're a semi-li-podcasts and videos. That's where I post my videos. Although the slides, you find them on the website, on the respective episode number.

And then, for people that are, if you want to get a notification whenever I make a new podcast, just subscribe to the website, divineinterventionpodcasts.com. And then, I also have these podcasts, on Apple Podcasts, on Google Podcasts, on Spotify. Although, it's going to be the most recent 150. I mean, it's a Word Press role. It's something that, sadly, I have, like, literally zero control over. So, if you want, like, the other podcasts from episodes like one, I mean, I guess this is episode two, E-D-Eat, if I'm doing my math rights, that means episodes one through one, 38, probably won't show up on Apple Podcasts, for example, right? So, if you want all the other podcasts, just go on the website. They're all there. They all, you know, God willing, be there. And they're all free again. You don't have to be to download any of my podcasts. They're all free. Even all the way to episode one. Okay. And the last thing I'll also say is, you know, if you need one or one tutoring for these exams, step one, step two, CK, step three, pre-clinical, medical exams, 30-ish-off exams, if you're a medicine resident, I need tutoring for the ABI and medicine boards, or the medicine-intrining exam. I'd love for tutoring for those. Again, I've worked with people that have had very, very, very low scores, very low scores, very low practice test scores starting out. In some cases, I've worked with people for like two weeks and they've bumped up by like 30 points.

So again, if you're interested in any of the students, feel free to reach out to me. And also, if you need help with your applications, I consult on your applications, like ER As applications, medical applications, I'd be more than happy to point you in the right direction. Again, I've been on an admissions committee for a year, and I've also worked with turns of people that again have very tricky applications, but now our residents are now medical students. So again, I have a lot of experience with this. What admissions committees are looking for, how to present yourself, even if you feel the USML exam or feel it multiple times, or have limited research, things like that, or you have to dig breaks in your education, again, I've dealt with many of those scenarios. So again, I'm more than happy to help you in those circumstances. Now, quickly, the life lesson I just want to share today is the importance of working in your area of gifting. The importance of working in your area of gifting. There's actually something that I've learned quite a bit from my church. Many people you see them, they see someone that's really successful at something, and they just jump right into it. They're like, the fact that this person has been successful. Boom, that means I can be successful in this thing as well. Again, I have this very strong belief that everyone has an niche. Everyone has a path that's carved out specifically for them.

So when you begin to work in areas that are not your areas of gifting, it's almost like you're trying to fit a round peg in a square hole, or a square peg in a round hole, whichever way it goes. So just encourage you to be careful with that. You can learn from people who don't copy them. You can learn from people who don't copy them. That's one very important thing. I think even in the Bible, Jesus says, learn from me. He did not say copy me. I think that's something that many people lose sight of in this day and age. When people see that, oh, a person is a Tik Tok sensation, or a person does this, or a person does that. They immediately want to become like that person. Again, learn from people who don't copy them. The thing is you're your only unique person. And this is one thing that unfortunately, because as you've noticed, for many of these lifeless things, I love to circle back to med students and residents and people in healthcare. You see some people they see like this person that seems to be really good at their job, or they are amazing surgeons, or they're amazing radiologists. Like they're just crushing it, whatever. And then they'd be like, you know what, radiology must be my calling. But they don't have any aptitude for it. It's not something that they really love. You need to be careful. Or you see some people, they see their friends doing this on key deck. They're like, wow, this on key deck that has 2 million cards.

Again, many people think that if something is on key, no. On key is actually a means it's one of the best things known to them. But again, it's not something that works for everybody. But people see that, oh, a person did on key. And they go to 270 or 280 on step one or step 2ck. So that means I must do on key to get a 272 million step 2ck or step one. No, you don't have to do that. I'll just tell you the truth. You really don't have to do that. Right? Again, even the Bible says that people that compare themselves with themselves is like a famous scripture you can look it up, comparing themselves with themselves and not wise. Right? You see many people they just like to make these comparisons. Well, maybe one thing that maybe more useful to learn from that on key person is, wow. Did he do something unique? Was there something about the study process that made them so succeed? I remember when I was studying for the MCAC back in the day, this was like 2013 or 2012. I remember, you know, there was this person that was a mentor of mine, crushed the exam, like crushed the exam. So I asked him, what study methods did you use? What study techniques did you use? What study resources did you use? Did I use many of the study resources that he used? No. But did I use many of the study approaches that he used? Yes. Did he work for me? He did. Right? So the thing is, in this case, I didn't copy him, work for what he did. I learned from what he did. Right?

And executed and thankfully was successful. Same thing with step one. Right? Again, you see many people like, oh, this huge ass-unkey deck, you know, is the key to a 280? No. You don't, again, there are people. Again, I can tell you from personal experience, I'm from experience I've worked with. You don't always have to, you can do onkey and getting the 270's to 80's. That's not what I'm saying. Right? But there are other many other things you can do. There are some people that don't touch the famous Cubans that people know. And they still crushed the exam. There are some people that don't touch any Cubans at all and just do just the MbME assessments. And they crushed the exam. That's why many times when I tell other people I like to hold like an introductory meeting for like an hour, where we just, I ask them many questions and I figure out like, okay, what will work best for you? What works best for another person? What made a person get a 270 using an onkey? It may not be the same thing that will make you get a 270. You could maybe get a 270 using a completely different resource that is off the bidding path. Obviously you should use like a well established resource. But again, just be mindful of that. Stop copying other people. Be unique in your own way. Right? Be unique in your own way. You may be passing across the same information, but maybe you can pass it across in a different modality, in a different way. Right? So again, just be unique.

Learn from people, but don't copy them. Right? Because again, you have a certain grace, you have a certain niche. Right? That other people don't have. Right? I just want to tell you this because some people are really down. I don't know if this is maybe a word of encouragement for someone. Some people are really down on themselves. The thing is, you're unique. Even if there are like 7 billion people in this world. Even if you're from a very poor family. Even if you're from a place of the world where people say, wow, nothing good can come out of this place. Let me tell you this. You're unique. You're especially in your own way. Right? I mean, like the Bible talks about how people say, oh, can anything good come out of Nazareth. Right? But Jesus, they were referring to, well, Jesus came from Nazareth. Or you see this Bible verse that says that there's this treasure in earthen vessels. So that earthen vessel is you. There's treasure inside you. You just have to find where your niche area is, where your area of giftedness. And then begin to use it to shine and be a star in the world that surrounds you. Right? So again, don't feel like, wow, you're stupid. Or maybe you have some genetic disease or you have like some disability that because of that, you're like the worst person in the world and you have no future. No, you have a future. There's there are bright things about your life. Right? There are things that are unique about you that no other person has. Right?

I mean, like I watched this movie yesterday for Valentine's Day for his dump. And I mean, the guy, you know, was he perfect in every way? No. Right? But hey, he could run. And you know, he may not have been perfect in every way, but that running, got him to college, meeting me, the president, what like maybe like twice. And all those things, right? So like, just be mindful of that. When you're down on yourself feeling like a failure. Remember, there is something special and unique about you. So I'm going to go ahead and pause here. I will see you in the next podcast. I hope you have a wonderful week and God bless you. I'll see you next time. Thank you.

A method of stress and a method of imaging.

Exercise (e.g., using a bicycle or treadmill protocol).

They cause hyperpolarization and relaxation of the coronary vessels via phosphodiesterase inhibition or adenosine analog action.

Severe hypertension (risk of severe BP spike) or unstable angina/acute coronary syndrome.

LPAE: Left Atrial Thrombus, Prosthetic Valve issues, Endocarditis, and Aortic Dissection.

Vasodilator-based testing (adenosine/regadenoson) because they are less dependent on electrical activity.

They cause hyperpolarization, leading to smooth muscle relaxation and coronary vasodilation.

Dobutamine increases myocardial oxygen demand (MVO2) via beta-1 agonism; in the setting of severe fixed stenosis, this increase can precipitate an MI.

Exercise testing (e.g., reaching 85% of target heart rate).

Endocarditis, suspected Left Atrial Thrombus, and prosthetic valve issues/Aortic Dissection.

Pregnancy, pediatric patients, or individuals with large breasts (due to increased artifact risk).

They cause hyperpolarization, leading to smooth muscle relaxation and coronary vasodilation.

Dobutamine increases myocardial oxygen demand (MVO2) via beta-1 agonism; in the setting of severe fixed stenosis, this increase can precipitate an MI.

Exercise testing (e.g., reaching 85% of target heart rate).

Endocarditis, suspected Left Atrial Thrombus, and prosthetic valve issues/Aortic Dissection.

Pregnancy, pediatric patients, or individuals with large breasts (due to increased artifact risk).