Atrial Fibrillation (AFib) — Symptoms, Stroke Risk and Treatment in Hyderabad
Atrial fibrillation (AF or AFib) is the most common sustained cardiac arrhythmia in adults — affecting an estimated 5 to 6 million people in India. In AF, the upper chambers of the heart (atria) fire chaotically instead of contracting in an organised rhythm, causing an irregular and often fast heartbeat. The consequences range from troublesome palpitations to disabling stroke.
What happens during atrial fibrillation?
Normally, the heart's electrical system generates a regular impulse from the sinus node — the natural pacemaker — that spreads in an orderly way through the atria and then the ventricles. In AF, the sinus node loses control. Hundreds of chaotic electrical impulses bombard the atria simultaneously, causing them to quiver rather than contract. The ventricles respond to some of these impulses irregularly — producing the characteristic irregular pulse.
The consequences of this disorganised activity are:
- Irregular heartbeat — felt as palpitations, a fluttering sensation, or an awareness of missed beats
- Often fast ventricular rate — the heart can race at 100 to 160+ beats per minute, reducing the time for cardiac filling and lowering output
- Blood pooling in the atria — particularly in the left atrial appendage — where clots can form and embolise to the brain, causing stroke
- Long-term — cardiomyopathy if the rate remains uncontrolled for months (tachycardia-induced cardiomyopathy)
Types of atrial fibrillation
| Paroxysmal AF | Episodes that start and stop spontaneously — lasting from minutes to days. Between episodes the heart rhythm is normal. Stroke risk is similar to persistent AF despite normal rhythm between episodes. |
| Persistent AF | AF lasting more than 7 days. Does not convert spontaneously — requires electrical or pharmacological cardioversion to restore normal rhythm. |
| Long-standing persistent AF | Continuous AF lasting more than 12 months. Rhythm control is less likely to succeed; rate control is often the primary strategy. |
| Permanent AF | AF where the decision has been made not to pursue further rhythm control — accepted as the ongoing rhythm. Rate control and anticoagulation are the management pillars. |
Symptoms of atrial fibrillation
- Palpitations — irregular, fast, or fluttering heartbeat — the most common presenting symptom
- Breathlessness — particularly on exertion — from reduced cardiac output and pulmonary congestion
- Fatigue and reduced exercise tolerance
- Dizziness or lightheadedness — from haemodynamic compromise during rapid ventricular rates
- Chest discomfort — can occur, particularly in patients with underlying coronary artery disease
- No symptoms at all — AF is frequently discovered incidentally on an ECG performed for another reason. Silent AF still carries the same stroke risk as symptomatic AF.