Chills Are Not a Typical Symptom of Atrial Fibrillation
Chills are not recognized as a characteristic symptom of atrial fibrillation (AF) in major clinical guidelines or research literature. If you experience chills alongside AF, this warrants evaluation for alternative causes such as infection, thyroid dysfunction, or other systemic illness.
Recognized AF Symptoms
The documented symptoms of AF are well-established and do not include chills:
Cardiac-Specific Symptoms
- Palpitations - the sensation of irregular or rapid heartbeat 1, 2
- Chest pain or discomfort 3, 2
- Presyncope or syncope (feeling faint or fainting) 2
Non-Specific Symptoms
- Fatigue - the most common symptom reported by patients with AF 3, 4
- Dyspnea (shortness of breath) 3, 2, 4
- Exertional intolerance - reduced ability to perform physical activities 2
- Dizziness or lightheadedness 4
Important Considerations About AF Symptoms
Approximately 10-40% of patients with AF are completely asymptomatic, meaning they have no symptoms at all 2, 5. The 2024 ESC Guidelines note that 90% of patients describe symptoms with variable severity, but even symptomatic patients may have some asymptomatic episodes 1.
The presence or absence of symptoms does not correlate with stroke risk, systemic embolism, or mortality - asymptomatic AF carries the same thromboembolic risk as symptomatic AF 1.
When Chills Occur With AF: Evaluate for Alternative Causes
If you experience chills in the context of AF, consider these possibilities:
Thyroid Dysfunction
- The diagnostic work-up for new AF includes thyroid function tests as a standard component 1
- Thyroid disorders can both cause AF and produce symptoms like chills (hypothyroidism) or heat intolerance (hyperthyroidism) 1
Infection or Sepsis
- Fever and chills suggest an infectious process that may be triggering or coexisting with AF
- Blood tests including full blood count should be performed to detect concomitant conditions 1
Medication Side Effects
- Some medications used to manage AF or its complications may cause chills as a side effect
Other Systemic Illness
- The comprehensive diagnostic assessment recommended for all AF patients includes evaluation for comorbidities that could explain additional symptoms 1
Clinical Pitfall to Avoid
Do not attribute chills to AF itself. The temporal association between AF episodes and symptoms has been studied, showing strong correlations with palpitations, shortness of breath, dizziness, and fatigue within 15 minutes of AF onset, but chills are not among the documented symptoms 4. Missing an alternative diagnosis (particularly infection or thyroid disease) could delay appropriate treatment.