Took some time last week to focus on my own learning gaps regarding DIGOXIN 💊 What are its 2 main indications? How does it work for those indications? How do we monitor toxicity and how do we treat? This is what I've learned, in a tweetorial🧵(graphic at the end!) /1

First, which is NOT an indication for Digoxin? /2

Indications for Digoxin are twofold. The first is rate control for certain tachy-arrhythmias (afib, aflutter, SVT). 🧐But how does this happen? Does it increase... /3

Digoxin indirectly⬆️baroreceptor sensitivity which ⬆️vagal tone, + prolongs AV node refractory period! This works best when pts are sedentary. Making Dig a rate control option in atrial or supraventricular tachycardias, esp in decompensated HF when BB or CCB contraindicated /4

The second (less common) indication for digoxin: HFrEF with NYHA III or IV symptomatology (ie severe symptoms with exertion or symptoms at rest). 🚨Caveat: this is a second-line agent, to be considered AFTER all standard GDMT /5

This relates to digoxin's more well-known mechanism, inhibition of the Na/K ATPase Pump! This process drives up intracellular calcium stores, which⬆️ inotropy. In other words, digoxin is a potential inotropic agent in HFrEF with NYHA III/IV symptoms despite standard GDMT /6

So we have talked about mechanisms and indications, but what about safety profile? Which is NOT a sign of digoxin toxicity? /7

Digoxin Toxicity presents as: Hyperkalemia - because it ❌ the Na/K pump Bradycardia or heart block - because ⬆️vagal tone Tachyarrhythmias because of its inotropic effect ⚡️ GI Upset (most common), Vision changes If we are concerned for toxicity, how would we treat? /8

Obviously, prevention is🔑 How? ✅Check digoxin level (does not correlate to toxicity well, but can determine compliance) 🧪Check electrolytes (hypoK ⬆️toxicity risk) 🚨Beware drug interaction 🫘 Monitor kidney fx (hence digoxin less commonly used outpt) ❤️EKG, telemetry /10

In summary: We started with 3 questions. ❓Digoxin indications ❓Mechanism(s) ❓Sx and Rx of Toxicity Take a moment to recall what we covered. Answers (in a graphic!) next. Thank you to @AdamRodmanMD and @ShreyaTrivediMD and @jasonmatosmd for their feedback on this🧵! /end