Neurologically intact survival following brady-asystolic cardiac arrest due to high-grade atrioventricular block managed with emergency transvenous pacing

High-grade atrioventricular (AV) block is a reversible cause of cardiac arrest resulting from failure of impulse conduction and ventricular standstill. Standard Advanced Cardiac Life Support (ACLS) measures, including atropine, vasopressors, and transcutaneous pacing (TCP), may be ineffective when conduction system failure is the primary pathology. The role of transvenous pacing (TVP) in brady-asystolic cardiac arrest remains underutilized. We report a 71-year-old male who presented with syncope and subsequently developed asystolic cardiac arrest in the emergency department. Following initial return of spontaneous circulation (ROSC), he was found to have high-grade AV block refractory to atropine, catecholamine infusion, and TCP. The patient developed recurrent cardiac arrest. Emergent transvenous pacing was performed via the right internal jugular vein under ultrasound guidance during ongoing cardiopulmonary resuscitation. Electrical and mechanical capture were rapidly achieved, resulting in immediate ROSC. The patient demonstrated complete neurological recovery, was extubated within 24 h, and later underwent permanent pacemaker implantation with a favorable outcome. This case highlights that conduction system failure is a reversible cause of cardiac arrest where conventional therapies may fail. Early transition to transvenous pacing can restore effective cardiac output, reduce no-flow time, and improve neurological outcomes. Ultrasound-guided TVP further enhances procedural success and safety in emergency settings.