How Serious Is an Irregular Heart Beat?

There are a number of causes for an irregular heartbeat. Sometimes, irregular heartbeat (arrhythmia) is a relatively benign condition. In other contexts, irregular heartbeats may be the precursor to a heart attack or an indication of some other serious problem.

Irregular heart beat (arrhythmia) refers to a change in the heart’s sequence of electrical impulses. Types of arrhythmias include:

• Tachycardia: heart rate is too fast (in adults, more than 100 beats per minute)
• Bradycardia: heart rate is too slow (in adults, less than 60 beats per minute)
• Palpitations: heart rate is irregular
• Atrial fibrillation (AFib): upper heart chambers contract irregularly
• Ventricular fibrillation (VFib):  disorganized contraction of the lower chambers of the heart
• Conduction disorders: heart does not beat normally
• Premature contraction (PACs and PVCs): early heart beat

Arrhythmia may not cause any symptoms or only minor symptoms such feeling as if you skipped a heartbeat or feeling of fluttering in the chest or neck. 

When symptoms of arrhythmia do occur, they may include:

• Fatigue 
• Weakness 
• Dizziness 
• Lightheadedness, fainting, or near-fainting spells 
• Rapid heartbeat or pounding in the chest 
• Shortness of breath 
• Anxiety 
• Chest pain or pressure 
• In severe cases, collapse and sudden cardiac arrest 
  • Cardiac arrest is a serious medical emergency and can be fatal. 
  • If someone you know is experiencing any symptoms listed below call 911 and get to a hospital’s emergency department immediately. 
    • Sudden loss of responsiveness 
    • No normal breathing (not breathing at all or gasping for air)

Arrhythmias may be caused by:

• Heart attack
• Heart changes with age
• Congenital abnormality of the heart’s electrical system
• Inherited heart disease 

Tests to diagnose arrhythmias include: 

• Electrocardiogram (“ECG”) 
• Stress test (treadmill test)
• Echocardiogram (“echo”)
• Electrophysiology test (EP study)
• Esophageal electrophysiologic procedure
• Tilt table test
• Diagnostic monitors
  • Holter monitor
  • Transtelephonic monitor
• Cardiac catheterization (“cardiac cath”) 
• Magnetic resonance imaging (MRI) scan of the heart 
• Computed tomography (CT) scan of the heart
• Blood tests: brain natriuretic peptide (BNP) or N-terminal pro-BNP (NT-proBNP) 

Treatment for arrhythmia includes:

• Medications  
  • Antiarrhythmics
    • Class I (fast sodium channel blockers) 
      • Quinidine
      • Procainamide
      • Disopyramide
      • Ajmaline
      • Lidocaine
      • Mexiletine
      • Phenytoin
      • Flecainide
      • Propafenone
    • Class II (beta-blockers)
      • Metoprolol
      • Esmolol
      • Propranolol
      • Atenolol
      • Timolol
      • Carvedilol
      • Sotalol
    • Class III (potassium channel-blockers)
      • Amiodarone 
      • Dronedarone
      • Sotalol
      • Bretylium
      • Ibutilide
      • Dofetilide
    • Class IV (calcium channel blockers)
      • Verapamil
      • Diltiazem
      • Nifedipine 
    • Class V (other)
      • Adenosine 
      • Digoxin
      • Magnesium sulfate
      • Anticoagulants (blood thinners) such as warfarin
      • Ablation
      • Cardioversion
      • Implantable devices
      • Implantable cardioverter defibrillator (ICD)
      • Pacemakers

Complications of irregular heartbeat include: 

• Heart attack
• Stroke
• Sudden cardiac death