Management of Second-Degree Heart Block

Initial Assessment and Management

The American College of Cardiology recommends management of second-degree heart block based on the type of block, presence of symptoms, and hemodynamic stability, with permanent pacing recommended for symptomatic patients or those with Mobitz type II block regardless of symptoms 1, 2

For patients with transient or reversible causes of second-degree heart block, the American College of Cardiology suggests medical therapy and supportive care, including temporary pacing if necessary, before determining the need for permanent pacing 1, 3
The American College of Cardiology recommends proceeding directly to permanent pacing for patients on chronic stable doses of medically necessary beta-blockers or antiarrhythmics with symptomatic second-degree block 1, 4
Atropine is reasonable to improve AV conduction and increase heart rate in patients with AV nodal block with symptoms or hemodynamic compromise, according to the American College of Cardiology and Circulation 2, 5
Beta-adrenergic agonists may be considered to improve conduction and heart rate in symptomatic patients with low likelihood of coronary ischemia, as suggested by the American College of Cardiology and Circulation 2, 5
Intravenous aminophylline may be considered to improve AV conduction in blocks associated with acute inferior MI, according to the American College of Cardiology and Circulation 2, 5

Temporary transvenous pacing is reasonable for symptomatic second-degree block refractory to medical therapy, as recommended by Circulation and the American College of Cardiology 2, 6
Temporary transcutaneous pacing may be considered for hemodynamic compromise refractory to medical therapy until transvenous or permanent pacing is established, according to Circulation 2

The American College of Cardiology and Circulation recommend permanent pacing for Mobitz type II second-degree AV block, regardless of symptoms 7, 8
Permanent pacing is recommended for symptomatic second-degree AV block, regardless of type, according to the American College of Cardiology and Circulation 7, 8
Permanent pacing is reasonable for cardiac sarcoidosis or amyloidosis with second-degree AV block, with defibrillator capability if needed, as suggested by the American College of Cardiology 1, 8
Permanent pacing is reasonable for symptomatic marked first-degree or Mobitz type I block when symptoms are clearly attributable to AV block, according to the American College of Cardiology 8

Asymptomatic vagally mediated AV block is a contraindication to permanent pacing, as stated by Circulation and the American College of Cardiology 7, 8

Ambulatory ECG monitoring is reasonable for patients with symptoms of unclear etiology who have first-degree or Mobitz type I block, as recommended by Circulation and the American College of Cardiology 7, 8
Exercise testing is reasonable for patients with exertional symptoms and first-degree or Mobitz type I block at rest, according to Circulation and the American College of Cardiology 7, 8
Electrophysiology studies may be considered to determine the level of block in selected patients with second-degree block, as suggested by the American College of Cardiology 8