brugada syndrome.

just gonna get right into it. no editorializing, just learning.

previously brugada syndrome is genetic. it causes an abnormal ECG. you’ll see ST elevation in the right precordial leads. so it might look like a STEMI but trust, it’s not.

stemi? if you’re healthy and you have it, you have increased risk of ventricular arrhythmia and sudden cardiac death.

if you have symptoms, they probably started when you were an adult around 41 years old. you might have gotten your first symptoms when you were a kid, though, or when you were elderly. it’s kinda all over the place in terms of age of onset.

if we’re looking at pathophysiology, we find our culprits in mutated cardiac channels (sodium, calcium, potassium) which prolong the duration of the action potential and cause arrhythmia.

we think that it’s the right ventricular outflow tract, as in, the uhmmmmm the ummmmmmmm point where the right ventricle pumps blood into the lungs........ it’s the right ventricular outflow tract that is the arrhythmogenic substrate. big word alert. just means the place where the arrhythmia starts.

most patients with brugada are asymptomatic. few patients actually have clinical manifestations. a silent little devil.

there’s something called spontaneous type 1 brugada, which we can see on ecg, and which helps us identify patients at higher risk of.... something..... death, I guess? and we can use an implantable cardioverter defibrillator (ICD) or quinidine in these patients.

oh, yes, sudden cardiac death, there we go, is the most common clinical presentation. so that’s what the risk is. that’s what we fear with brugada is that they’re going to suddenly die, and then when they’ve died that’s when we’ll figure out that they have brugada. scary world!!! scary!!! patients may also present with syncope and palpitations.

we do recommend ICD in patients with symptoms. better to have a device implanted in your fuckin chest than to die suddenly i guess? i think you gotta be hooked up to the wall at times when you have that thing. but i don’t recall. just something my nurse friend told me, but it might’ve been about something else. i don’t wanna spread fake news. but if you have brugada with symptoms you might have to go bionic.

if you have the ICD and you’re experiencing recurrent shocks (because the device shocks you out of unstable rhythms i think?), you gotta optimize your regimen!!! you gotta add quinidine or do a catheter ablation. as in, zap part of your heart so it stops misbehaving. literally zap it. destroy it.

if you’re asymptomatic, we don’t really know what to do with you. there’s a lot of ambiguity about disease severity in asymptomatic patients. sorry!

anyway, let’s really lock down our definition. brugada syndrome is fully like an ecg thing. it’s made up. it’s just looking at lines on the paper. look at the lines, and if you see ST segment elevation in one or more of V1 or V2 which occur spontaneously or after provocative IV administration of sodium channel blockers, you have brugada. just look at the lines. you have to exclude other causes of ST elevation, of course.

in terms of background, let’s get into background. prevalence seems to be somewhere between one in five thousand and one in two thousand. so it’s like… rare, kinda, but not like crazy super duper rare.

brugada is inherited. it’s genetic. it’s an ion channelopathy. something wrong with your ion channels. it’s associated with mutations in SCN5A, which encodes for the cardiac sodium channel. there are 18 other genes taht have been implicated as well. i won’t name all of them.

as we said, brugada can present with syncope. it can also present with seizures and nocturnal agonal breathing (gasping, gurgling, moaning, abnormal breaths) due to polymorphic ventricular tachycardia (PVT) or ventricular fibrillation (VF). sudden cardiac death can result from sustained PVT or VF. v fib. ever heard of it? it’s afib’s much much worse brother. sibling. sibling. keep it gender neutral. vfib and afib are siblings. vfib is worse. afib you can live with for much longer, as we’ve said previously.

per my last email brugada is inherited with an autosomal dominant pattern. that means you’re kinda fucked if even one of your parents has it. you got that shit if your parent has it. it’s not going away. this shit is hereditary in the realest of ways. there’s no genetic lottery you can hit other than being born to some other parents, and we all know things don’t work that way. it does have variable expression, though, so that’s why it’s possible for one person who has it to be asymptomatic, and another to die from sudden cardiac death. it can cause sudden death in an otherwise normal-appearing heart!! scary!!!!

when someone has a brugada-looking ecg without symptoms, we just call this brugada pattern. we don’t call it brugada syndrome until you have clinical manifestations. it’s way more common to have brugada pattern than brugada syndrome.

what are the risk factors? you should be able to guess the first one. here, i’ll tell you: family history. right? because it’s genetic. you get it. men are diagnosed more than women. it happens more frequently in asians. sorry asians. love y’all. fever can irritate the myocardial fibers and cause fainting or sudden cardiac arrest, especially in children. so like, a kid gets a fever, and they can get a brugada related death. watch out!!!!!! constant vigilence!!!! YOU COULD LITERALLY DIE AT ANY MOMENT!!!!! DON’T FORGET!!!!!!! other risk factors are increased vagal tone, alcohol, cocaine use, and tricyclic antidepressants.

we can talk a little more about pathogenesis i guess, but i feel like we’ve kinda gotten the long story short already. like i feel like i know brugada now sufficiently for this test. but fuck it, let’s see what else there is. the cardiac action potential depends on ion channels, so if the channels are fucked up, you’ll get arrhythmia, because the action potential is out of whack, and it’s the action potential that initiates the heart beat. channel not working equals action potential not working equals electrical system in the heart fucked up. yeah, it’s a decrease in inward sodium/calcium current, or an increase in outward potassium current. man, i really love action potentials so we could really go down that rabbit hole, but i’ll save it for another day. that’s all for pathogenesis, then. let’s leave it at that.

on to clinical features. i feel like we covered that, but let’s do it again. sudden cardiac death is the big one and it’s because of vfib. scary as fuck. this is how you find brugada in up to a third of patients. scary!!!! you don’t know you have it til you die and then you don’t know anything cuz you’re dead. scaryyyyY!!!!!!! it can also present with palpitations, seizure, syncope, nocturnal agonal respiration, chest discomfort. it often kills you in your sleep. my god. scary. that tells us it might be associated with bradycardia or vagal events. it sneaks in right when you let your guard down. that’s so scary bruh holy shit damn, okay. fine. wow. jesus. silent killer and killer of people in their sleep. i guess it’s merciful in a way but damn, still, damn.

what else is on our differential? as in, other things we might consider if we suspect brugada? early repolarization syndrome, atypical bundle branch block, left ventricular hypertrophy… blah blah a bunch of other heart shits.

how to diagnose? of course it’s just ecg. get the 12 lead ecg. you diagnose the patient when they have a type 1 ecg pattern spontaneously or after provocative drug testing with sodium channel blocker. like i said before. you can also get an echo and cardiac mri to rule out structural heart disease. what the hell, sure. why not.

how to manage it? in the acute setting, like if someone has an “electrical storm” (the fuck?) you should give an isoproterenol infusion. give oral quinidine if that doesn’t work. if neither of those work, do an emergent catheter ablation to prevent ventricular arrhtyhmia. cuz vfib is the killer, folks. you also want to eliminate reversible factors like fever, coke use, electrolyte disturbances. discontinue anything that is known to trigger arrhythmias.

for chronic management, we recommend ICD. we need something in their literal body connected to their literal heart that forces the heart to beat correctly if it steps out of line. it zaps your heart when it notices an arrhythmia. it’s like a techno cop inside your body making your heart stay in line. again, we don’t give ICD for asymptomatic patients. we also want to avoid hypokalemia, carb-heavy meals, alcohol, and hot baths. like yeah, sure.

in terms of prognosis, our grand finale, patients with history of arrhythmia have increased risk of another episode. so if you have arrhythmia once, you’ll probably get it again. if you have a history of syncope, that increases your risk. yeah, they don’t really give us any juicy details about prognosis, but i think it was juicy enough earlier. we know it causes sudden cardiac death. i don’t know how much or how often, but i get bad vibes from this thing. just be wary.

that was a little bit of a downer, but an exciting downer. now it’s time to move on to something even more foreboding.