Understanding Atrial Fibrillation for Student Nurses
Learn what atrial fibrillation means, recognise common clinical features and understand how pulse, symptoms, observations and ECG findings contribute to assessment.
What is atrial fibrillation?
Atrial fibrillation, often shortened to AF, is a common cardiac arrhythmia in which electrical activity in the atria becomes disorganised. This produces an irregular ventricular rhythm.
The atria become disorganised
Normal coordinated atrial electrical activity is replaced by irregular electrical activity.
The rhythm may feel irregular
A patient's pulse may appear irregular, although pulse assessment alone cannot confirm AF.
Patients respond differently
Some patients experience obvious palpitations or breathlessness, while others have few or no symptoms.
What might you notice?
Fluttering or racing
Patients may describe racing, fluttering, pounding or irregular heartbeats.
Irregular rhythm
Clinical pulse assessment may reveal an irregular rhythm that is different from the patient's previous findings.
Breathlessness
Some patients experience new or worsening breathlessness, particularly if the ventricular rate is poorly tolerated.
Dizziness or weakness
Reduced exercise tolerance, dizziness or general weakness may be reported.
Chest discomfort
Significant new chest pain or discomfort should increase concern and prompt appropriate assessment.
AF may be unnoticed
Some patients may have AF without being aware of any rhythm disturbance.
What does “irregularly irregular” mean?
AF is classically associated with a rhythm in which there is no predictable pattern between beats. However, this description should support recognition rather than be used by a student nurse to make an independent diagnosis.
Assess the rate
Identify whether the pulse appears faster, slower or similar to the patient's usual baseline.
Assess the rhythm
Notice whether the pulse appears regular or irregular according to your competence and local practice.
Compare with baseline
Determine whether the irregularity is known, chronic or newly identified.
Check symptoms
Ask about palpitations, chest discomfort, breathlessness, dizziness and faintness.
Assess observations
Connect the pulse finding with blood pressure, respiratory observations, perfusion and wider ABCDE assessment.
Escalate a new change
Communicate a newly irregular pulse or deterioration for appropriate further assessment.
Why is an ECG important?
ECG assessment allows clinicians to examine the heart's electrical activity and determine whether the rhythm is consistent with atrial fibrillation or another arrhythmia.
The rhythm needs evidence
An ECG provides electrical information that pulse assessment alone cannot provide.
Rate also matters
Clinical teams assess both the rhythm and how rapidly the ventricles are responding.
The ECG is not the whole patient
ECG findings must still be interpreted alongside symptoms, haemodynamic status and clinical history.
Why does atrial fibrillation matter?
AF can have important cardiovascular consequences. Its significance depends on factors including the patient's symptoms, ventricular rate, circulatory stability, duration of AF and wider medical history.
Symptoms can develop
Some patients may develop dizziness, breathlessness, reduced exercise tolerance or other symptoms.
Some patients become unstable
A rhythm disturbance associated with hypotension, chest pain or altered consciousness requires urgent assessment.
AF has wider implications
AF is associated with an increased risk of thromboembolic stroke, which is why longer-term clinical assessment and management may be required.
Assess deterioration around the rhythm
Airway
Address immediate airway concerns according to local emergency procedures.
Breathing
Assess respiratory rate, oxygen saturation, work of breathing and new breathlessness.
Circulation
Assess pulse, blood pressure, peripheral perfusion, symptoms and relevant cardiac monitoring.
Disability
Assess consciousness and recognise dizziness, syncope or new neurological change.
Exposure
Complete the wider assessment and identify other clinically relevant findings.
Escalate
Use local emergency pathways immediately when the patient is significantly deteriorating.
When an irregular rhythm becomes more concerning
- A new irregular pulse with significant chest pain or chest discomfort.
- An irregular rhythm associated with severe or worsening breathlessness.
- Syncope or near-syncope associated with a rhythm change.
- Falling blood pressure with new cardiovascular symptoms.
- New altered consciousness or reduced responsiveness.
- Signs of poor peripheral perfusion with a significant pulse change.
- Rapidly worsening physiological observations.
- Any new rhythm abnormality in a patient who appears acutely unwell.
A patient's pulse becomes newly irregular
Example
During routine observations you notice that a patient's pulse feels noticeably irregular compared with earlier assessments.
The patient tells you they can feel their heart fluttering and have become slightly breathless when walking to the bathroom.
You do not tell the patient they have AF. Instead, you recognise new pulse irregularity + palpitations + breathlessness and communicate the change for appropriate assessment.
Further clinical and ECG assessment can then determine the underlying rhythm.
Report the finding without making the diagnosis
Example escalation
“I'm concerned because Mrs Patel's pulse is now irregular compared with her earlier observations. She reports new palpitations and has become breathless on mobilisation. Her other observations are...”
This communicates the new rhythm finding + symptoms + change from baseline while leaving formal rhythm diagnosis to appropriate ECG and clinical assessment.
Not every irregular pulse is a new emergency
Some patients have established atrial fibrillation and may have a chronically irregular pulse. Baseline information and current symptoms therefore matter.
Is this normal for them?
Review available information and establish whether the irregular rhythm is already known.
Has something altered?
A significant change in rate, symptoms or physiological status may still require escalation.
Are they clinically stable?
Assess the patient rather than assuming known AF explains all new symptoms.
Atrial fibrillation assessment errors to avoid
- Diagnosing AF from pulse palpation alone.
- Assuming every irregular pulse is atrial fibrillation.
- Ignoring associated symptoms and blood pressure changes.
- Failing to establish whether AF is already known.
- Focusing on rhythm while ignoring wider ABCDE deterioration.
- Assuming known AF explains every new symptom.
- Trying to perform advanced ECG interpretation beyond your competence.
- Delaying escalation while trying to identify the exact rhythm.
Recognise → assess → connect → escalate
Notice rhythm change
Identify a newly irregular pulse, monitor change or patient report of palpitations.
Look at the whole patient
Connect the rhythm finding with symptoms, blood pressure, perfusion, breathing and wider observations.
Escalate meaningful change
Describe the rhythm abnormality and how the patient's clinical condition has changed.
Recognise the rhythm change. Assess the patient behind it.
Clinical confidence does not mean diagnosing every arrhythmia. It means noticing important changes, connecting them with symptoms and observations and escalating appropriately.
Explore Clinical Confidence →