Slide 1: Recent hospitalization for afib w/ RVR… Now with fatigue and dyspnea on exertion. [ECG] What’s the rhythm?
Slide 2: Atrial Activity: No discernible P waves + fine fibrillatory waves = atrial fibrillation. | Ventricular activity: regular rhythm + no A to V relation = complete heart block. Complete heart block + narrow QRS = junctional escape rhythm. Junctional escape rhythm typically 40-60 bpm arising from AV node and maintaining a similar morphology to the native QRS. | If the AV node fails to generate an impulse, the ventricular myocytes could kick in and provide a ventricular escape (w/ wide QRS). But if no cell fires? -> Asystole! | What do you think caused this?
Slide 3: Beta blocker or calcium channel blocker toxicity! ECG findings in beta blocker or calcium channel blocker toxicity: 1st, 2nd, or 3rd degree AV block. Junctional or ventricular bradycardia. !st degree AV block -> prolonged PR interval can be one of the earliest signs, even before bradycardia, although if pt remains in afib, no PR interval to alert us! | What’s the treatment?
Slide 4: Your BB/CCB toxicity toolkit. Hold the meds and give: calcium for CCB toxicity, glucagon for BB toxicity (via its effect on intracellular calcium stores, can cause n/v). If unstable, use ACLS bradycardia (if altered, consider intubation for airway protection): atropine, pacing, beta agonists/inotropes. And don’t forget…call toxicology (poison control hotline: 1-800-222-1222)!
Tags: afib, beta blocker, bradycardia, calcium channel blocker, cardiology, ecg, electrophysiology, heart block, junctional escape rhythm