75-year-old presents with syncope. ECG: HR 38 bpm, P waves dissociated from QRS. BP 80/50. No reversible cause found. What are the immediate and definitive management steps?
Complete Heart Block (3rd Degree AV Block) Management: Immediate Actions: 1. IV Atropine 0.5 mg (repeat up to 3 mg total) - may help if block is at AV node level (narrow QRS escape), less effective for infra-Hisian block (wide QRS) 2. If atropine fails: Transcutaneous pacing (TCP) - immediate bridge therapy 3. Dopamine or Epinephrine infusion if TCP not available immediately Definitive Management: - Temporary transvenous pacing (TVP): Rapid, reliable pacing for hemodynamic stability - Right femoral/internal jugular/subclavian approach - Target: HR 60-80 bpm, ensure capture and sensing - Investigate reversible causes: ACS (inferior MI), drug toxicity (digoxin, beta-blocker, CCB), electrolyte abnormalities, Lyme disease, post-cardiac surgery Permanent Pacemaker Indications: - Complete heart block without reversible cause (Class I) - Persistent CHB after reversible cause treated - Symptomatic Mobitz II second-degree AV block For your patient: - HR 38, BP 80/50, complete dissociation = hemodynamic compromise - Start IV Atropine immediately, prepare for TCP - Urgent temporary transvenous pacing - Rule out: inferior MI (ECG for ST changes in II, III, aVF), digoxin toxicity, electrolytes - If no reversible cause found: permanent pacemaker implantation Pacemaker type: DDD or VVI depending on sinus node function
Be specific. Your credentials will be shown with your answer.