Asynchronous Pacing in Bradycardia: Clinical Guidelines

Clinical Indications for Temporary Transvenous Pacing

The American College of Cardiology recommends temporary transvenous pacing in patients with persistent hemodynamically unstable sinus node dysfunction or bradycardia refractory to medical therapy, with a Class IIa recommendation, until a permanent pacemaker is placed or the bradycardia resolves, in patients with severe symptoms or hemodynamic compromise 3, 4
Patients with complete heart block, ventricular asystole, or severe symptomatic bradycardia causing syncope, altered mental status, hypotension, shock, or acute heart failure are primary candidates for temporary pacing, according to the American College of Cardiology 5

The American College of Cardiology advises against temporary transcutaneous or transvenous pacing in patients with minimal and/or infrequent symptoms without hemodynamic compromise, with a Class III recommendation, as the benefits do not outweigh the risks 3, 4
Asymptomatic bradycardia, sleep-related bradycardia, or physiologic sinus bradycardia in athletes should never be paced, according to the American College of Cardiology 1, 7

The American College of Cardiology recommends demand mode (VVI/AAI/DDD) as the preferred pacing mode for most situations, to avoid competition with intrinsic rhythm and reduce the risk of R-on-T phenomenon, with asynchronous mode (VOO/AOO/DOO) reserved for specific situations where sensing is unreliable or impossible, or the patient is completely pacemaker-dependent 2, 5

Lead dislodgement occurs in 16% of cases, with 50% happening within the first 24 hours, requiring continuous arrhythmia monitoring until removal or replacement, according to the American College of Cardiology 5, 6
Delaying transcutaneous pacing in unstable patients failing atropine is a common error, and transcutaneous pacing should be initiated immediately in unstable patients unresponsive to atropine, with a Class I recommendation for continuous arrhythmia monitoring until device removal or replacement 8

Standard temporary transvenous pacing wires should be replaced with a permanent pacemaker or removed as soon as clinically feasible, typically within 2-19 days depending on clinical stability, with continuous arrhythmia monitoring maintained until device removal or replacement, according to the American College of Cardiology 6