When is a temporary pacemaker used?

When Temporary Pacemakers Are Used

Temporary pacemakers are used to acutely treat life-threatening bradycardia causing hemodynamic instability or severe symptoms, serving as a bridge until either a permanent pacemaker can be implanted or the underlying reversible cause resolves. 1

Primary Indications

Hemodynamically Unstable Bradycardia

• Temporary transvenous pacing is reasonable for persistent hemodynamically unstable sinus node dysfunction refractory to medical therapy (Class IIa recommendation). 1
• Specific scenarios include prolonged symptomatic pauses, life-threatening ventricular arrhythmias mediated by bradycardia, or severe symptomatic bradycardia from a reversible cause. 1
• Temporary transcutaneous pacing may be considered for severe symptoms or hemodynamic compromise as a bridge to transvenous or permanent pacing (Class IIb recommendation). 1

Acute Myocardial Infarction

• Complete atrioventricular block after acute anterior infarction is an immediate indication for temporary pacing, as His-Purkinje necrosis typically causes cardiogenic shock and will not respond to atropine. 1
• Second-degree atrioventricular block complicating anterior MI warrants temporary pacing. 1
• Right bundle branch block with left posterior or anterior hemifascicular block may require prophylactic temporary pacing. 1

Conduction System Disease

• Important bradycardia due to atrioventricular block or sinoatrial disease causing symptoms. 1
• Symptomatic complete AV block represents the most common indication (51% of cases in one series). 2
• Symptomatic sick sinus syndrome when hemodynamically significant. 2

Reversible Causes

• Bradyarrhythmia due to drug intoxication (12.2% of cases), allowing time for drug clearance. 2
• Spinal cord injury with hemodynamically significant sinus bradycardia refractory to atropine and adrenergic drugs. 1
• Post-cardiac surgery, particularly after aortic valve repair, tricuspid repair, ventricular septal defect closure, or ostium primum repair. 1

Special Situations

• Overdrive pacing for unstable tachydysrhythmias such as torsades de pointes or long QT interval-related ventricular tachycardia. 2, 3
• Prophylaxis during replacement of infected permanent pacemaker systems (14.7% of cases). 2
• Bridge to permanent pacemaker when immediate implantation is not feasible. 4, 5

Critical Decision Points

When NOT to Use Temporary Pacing

• Temporary pacing should not be performed in patients with minimal or infrequent symptoms without hemodynamic compromise (Class III: Harm recommendation). 1
• Avoid when central venous cannulation is risky (e.g., soon after thrombolysis). 1
• Do not use in pulseless bradycardia—this requires immediate CPR and the cardiac arrest algorithm, not pacing. 6

Route Selection

• Transvenous pacing via right ventricle is the standard approach for emergency temporary pacing, providing rate support regardless of whether bradycardia is from sinus node dysfunction or AV block. 1
• Femoral venous route is preferred post-MI when compression is easily achieved. 1
• Internal jugular or subclavian veins are optimal for longer-term temporary pacing. 3
• Transcutaneous pacing serves only as a bridge to transvenous pacing and is not a substitute. 1

Important Caveats

Complication Awareness

• Serious complications occur in approximately 22% of patients, ranging from femoral hematoma to cardiac tamponade and death (6% mortality, though only 0.6% directly attributable to the procedure). 2
• Lead displacement requiring repositioning occurs in 9% of cases, with 50% of displacements happening within the first 24 hours. 7, 2
• Infection risk increases significantly with temporary pacing wires before permanent implant, making duration minimization critical. 1, 7

Duration Considerations

• Average duration of temporary pacing is 4.2 days (range 1-31 days). 2
• If prolonged temporary pacing is required beyond 24-48 hours, consider externalized permanent active fixation lead (Class IIa recommendation), which has lower dislodgement risk and allows patient ambulation. 7, 5

Common Pitfalls

• Do not use atropine for infranodal AV block—it may paradoxically worsen the block. 8
• Ensure proper verification of electrical capture, mechanical capture, and sensing function before relying on the device. 7
• Remember that 69.6% of patients receiving temporary pacemakers ultimately require permanent pacemaker implantation. 2