Arrhythmias FM Lecture Series

1. ArrhythmiasFM Lecture Series Alex Dworak July 2008

2. Needless photo of the author with his no-ponytails-until-you’re-in-college son The obligatory objectives slide • Review common and significant arrhythmias and EKG findings • Focus on recognition, etiology, immediate and definitive management • References: Uptodate, ECGlibrary.com

3. Basic principles of any arrhythmia • Is the patient stable or unstable? If unstable, call Code Blue and follow ACLS. If unsure, call a code—you’ll get help fast, & the ICU team would rather have a “fake code” than a too-late code • No palpable central pulse in the unstable patient means start CPR; a dopplerable pulse won’t perfuse the brain • If stable, stop and think. Call for help from your supervisor or staff. Check code labs (CBC, CMP, Mg/Phos, cardiac enzymes, blood cx) and get a 12 lead EKG. Consider calling Cards if appropriate. • Make sure the wires are hooked up/it’s not artifact. • The telemetry nurses usually recognize what’s worth freaking out about—don’t tune them out.

5. VT (Ventricular Tachycardia) • “A PVC is just a PVC, but 3 in a row is Vtach!” • Cause: MI, other structural disease, severe electrolyte change • Immediate: If unstable, SHOCK! If stable (talking, maintaining BP), calmly call Cards while the pads are being attached; consider Amiodarone or Lidocaine bolus, head for the ICU or cardiac floor • Definitive: May need AICD, especially if EF<35% to lower chance of sudden death

7. Normal/ “Confidence Builder” • Examine rate, rhythm (sinus or not—P before every QRS?), axis (left thumb is I, right is AVF—if both “thumbs up,” axis is normal, whereas a down thumb is deviated in the direction of that hand). • Look at ST segments, width of QRS, check for Q waves, PR depression, weird P waves, flipped/peaked T waves or U waves, excess QT interval length • Machine is good at rates and intervals; don’t always trust its interpretation, though! “We read the bottom of the EKG, not the top.” • Take advantage of Dr. O’Dell’s EKG sessions and practice on every EKG you get! (Same goes for Xrays!)

8. Too much digitalis…

9. Atrial flutter • Cause: Non-conducted atrial beats, usually in structurally abnormal heart • Characteristically 300 bpm • Not always obvious; 2:1 aflutter (unlike the 16:1 previously) can be both occult and dangerous—consider it with any narrow complex tachyarrhythmia with rate ~150 bpm • Immediate: If unstable, shock. Otherwise, IV metoprolol 5 mg q5min x3 or IV diltiazem drip with bolus; esmololgtt in ICU or verapamil are also considerations. Watch for hypotension. • Definitive: Electric vs. drug cardioversion in consultation with Cards; may need clot prophylaxis

11. Ventricular Fibrillation • SHOCK! This and unstable VT should always be shocked. • Make sure the leads are hooked up and the patient is actually unstable and pulseless before you hit the button • Definitive: Let Cards and EP sort out the best management; stabilize and then get the patient to the ICU.

13. Torsades des pointes • Cause: MI, hypoK+, hypoMg++, long QT, drugs (antiarrhythmics, TCAs…) • Immediate: If unstable, shock! Empirically give 1-2 g IV Mg++ (careful if they have renal failure—but intubation is easier than reanimation…) • Definitive: Correct underlying cause, maybe ICD. Consult Cards.

15. Complete heart blockwith idioventricular escape rhythm • Cause: MI or other disruption of conducting system • No relation of P to QRS • Immediate: tele monitoring • Definitive: Cards consult for EP workup and pacing

17. Acute anterior MI • Causes: thrombosis, drugs (cocaine, meth) • Immediate: ACLS • Definitive: Percutaneous stent vs. CABG depending on anatomy at cath and risk factors (i.e. DM) • No beta blockers for coke abusers

18. Look for the P waves

19. 2:1 AV block • Could be either Mobitz I (“Wenke walks away”) or Mobitz II (“Moby falls down like he got kicked in the head”?) • Mobitz I has repetitively lengthening PR until the dropped beat, then resets • Mobitz II just drops a beat suddenly; unstable and needs pacing • Can’t tell if it’s 2:1; assume it’s Mobitz II, put on telemetry and get Cards eval

20. Chest pain, got hypotensive with NTG in the ambulance.

21. Posterior MI • Usually not isolated; lateral involvement common • ST depression in V1, V2 is actually inverted STEMI on the back of the heart in the RV • Immediate: PRELOAD dependent, give lots of fluids (may need to intubate if they’ve got LV involvement too) and the usual ACLS • Definitive: same as any MI

23. Afib with RVR • Usually in the context of known afib • Treatment is same as for aflutter: • Immediate: If unstable, shock. Otherwise, IV metoprolol 5 mg q5min x3 or IV diltiazem drip with bolus; esmololgtt in ICU or verapamil are also considerations. Watch for hypotension. • Definitive: Electric vs. drug cardioversion in consultation with Cards; definitely needs clot prophylaxis unless a good reason not to

24. Credits, Suggested Reading • www.ecglibrary.com • www.uptodate.com • Pocket ACLS survival guide (must have, <$10 at bookstore) • Pocket EKG survival guide • Hurst’s The Heart or Braunwald if you’re really gung-ho Cake is the best!

25. Torsades des feet. • Completely unrelated video of (Christian) Taekwondo practitioners doing 540 tornado kicks—yes, it’s totally useless in a real fight, but I’d like to see any haters try one and not land on their faces.  • Separate (techno!) video of two credible Darth Maul impersonators