sinus arrest/pause

Introduction

A pause in or arrest of sinus activity. The p-p interval of the pause should not be a multiple (i.e. 2X, 3X etc.) of the baseline p-p interval (See sinoatrial exit block).

Etiology

• excess vagal tone
  • syncope due to neurocardiogenic vasodepressor dysfunction
• pharmacologic agents
  • digitalis toxicity
• degenerative fibrotic changes
• acute myocardial infarction
• electrolyte imbalances

Clinical manifestations

• lightheadedness
• dizziness
• syncope or presyncope

Management

• correct underlying cause
• consider permanent cardiac pacemaker if pause > 3 seconds
  • pacemaker reduces recurrence of syncope

More general terms

• sinus bradycardia

Additional terms

• sick sinus syndrome; atrial fibrillation with bradyarrhythmia; tachycardia-bradycardia syndrome
• sinoatrial exit block
• sinus arrhythmia