Approach to palpitations

Not all palpitations are due to arrhythmia

Investigations usually occur between episodes due to palpitations’ transient nature.

Diagnosis begins with patient history, physical examination, and a 12-lead electrocardiography (ECG).

Palpitations are a common issue, comprising 16% of general practice visits, and are second only to chest pain in cardiology visits.

Aetiology

1. Cardiac vs. Non-Cardiac Causes: Assess whether palpitations have a cardiac origin (e.g., arrhythmias) or are linked to other factors such as psychological conditions (anxiety, panic attacks) or systemic issues.
2. Common Arrhythmias: Identify the most likely arrhythmic causes based on patient age and clinical presentation:
   • Younger patients: Consider supraventricular tachycardias like AVNRT or AVRT.
   • Older patients: Atrial fibrillation or atrial flutter might be more common.

1. The small circuit in dots represents typical AVNRT, short dashes represent (orthodromic)
2. AVRT (via a right free wall pathway represented by the red dashes), and long dashes represent atrial flutter.
3. The yellow arc represents the AV node.
4. AVNRT, atrioventricular nodal re-entrant tachycardia; AVRT, atrioventricular re-entrant tachycardia; RA, right atrium; LA, left atrium; RV, right ventricle; LV, left ventricle

History Taking

1. Detailed Symptom Description:
   • Onset and offset: sudden or gradual
   • Duration: momentary or sustained (how long?)
   • Frequency
   • Associated symptoms – higher arrhythmia risks
     • Pre-syncope/syncope
     • Breathlessness
     • Chest pain
     • palpitations that disrupt sleep
     • regular pounding sensations in the neck
     • visible neck pulsations
     • vasovagal symptoms like pallor or sweating
2. Precipitating Factors: Identify any triggers such as exercise, stress, or caffeine intake.
3. Previous Cardiac History: Determine if there is a history of heart disease, prior episodes of similar symptoms, or family history of cardiac issues.
4. Exercise and Alcohol: Excessive endurance sports and alcohol intake are risk factors for developing cardiomyopathies and arrhythmias.
5. Medication and Substance Use: substance use, particularly stimulants and weight loss drugs
6. One of the causes of palpitations is simply an increased awareness of normal sinus rhythm.The patient may describe a forceful beating in the chest or neck that is not particularly fast; they may be able to hear their own heartbeat, particularly at night in bed. Although there may occasionally be secondary causes, in the vast majority of cases this is benign. It may often occur at times of heightened anxiety.

Monitoring with Heart Rate Devices

• Usage Concerns: Patients often seek medical advice after noticing an abnormal heart rate on personal monitoring devices.
• Device Accuracy: These devices, particularly during physical activity, are prone to inaccuracies, producing falsely high or low readings.
• Interpretation of Readings: An abnormal reading is concerning only if accompanied by other symptoms like dizziness or chest pain.

Sustained Palpitations

• Types and Causes:
  • Sinus Tachycardia: Usually benign and related to stress or emotional distress; however, it could be symptomatic of underlying issues like thyrotoxicosis or anemia.
  • Sudden Onset Palpitations: Can be either regular or irregular. Regular sustained rapid palpitations are most commonly due to SVT, while irregular ones might suggest atrial fibrillation.
• Duration: These palpitations gradually start and stop but can persist from several minutes to days, depending on the underlying rhythm disturbance.

Presentation and Management of Rapid Regular Palpitations

• SVT Characteristics: Often triggered by sudden movements like bending; in athletes, may manifest as a rapid increase in heart rate during exercise.
• Symptoms During Episodes: Can include sudden onset of light-headedness, chest discomfort, or difficulty breathing.
• Response to Vagal Maneuvers: Many patients can stop an SVT episode through techniques like the Valsalva maneuver or applying a cold stimulus to the face.

Ventricular Tachycardia

• Presentation and Symptoms: Rarely presents solely with palpitations; typically accompanied by signs of hemodynamic instability such as fainting, sweating, chest pain, or severe breathlessness.
• Contextual Importance: Most often occurs in individuals with structural heart diseases, such as those who have had a previous myocardial infarction.
• Management: Requires immediate medical attention, especially for sustained episodes, due to the risk of severe outcomes.

Rapid Irregular Palpitations: Atrial Fibrillation

• Symptoms: Characterized by extremely irregular and quick heartbeats, frequently accompanied by difficulties during exertion and potential breathlessness.
• Related Health Issues: Night-time episodes may indicate a vagal trigger or a correlation with sleep apnea.
• Management Considerations: Treatment and management decisions are based on the frequency, duration, and impact of the palpitations on the patient’s life.

Physical Examination

1. General Assessment:
   • Check for signs of distress, anxiety, or physical discomfort
   • weight (obesity may contribute to atrial fibrillation)
2. Cardiovascular Examination:
   • abnormal resting heart rate (<60 beats per minute or >100 beats per minute)
   • Listen for irregular heartbeats/murmurs,
   • signs of heart failure
   • Fluid status and postural blood pressure/heart rate
3. Systemic Examination:
   • abnormal resting heart rate (<60 beats per minute or >100 beats per minute)Look for signs of
   • thyroid disease (goiter, tremor)
   • signs of anemia

Diagnostic Work-Up

The gold standard diagnostic technique for a patient with palpitations is to be monitored using a 12-lead electrocardiogram (ECG) at the time of symptoms.

However, due to the transitory nature of arrhythmia, this method tends to be the exception rather than the rule

1. Initial Screening with ECG: Check for pre-excitation patterns, signs of ischemia, or other abnormalities that might suggest a specific arrhythmia.
2. Extended Monitoring: critical component of interpreting the ambulatory ECG is the rhythm at time of symptoms, and it should ideally also document the arrhythmia onset and/or offset
   • Holter Monitor: For frequent symptoms occurring daily.
   • Event Recorder: For less frequent symptoms, allowing longer monitoring periods.
   • Implantable Loop Recorder: For very infrequent symptoms or when other methods fail to capture the arrhythmia.
3. Echocardiogram: Assess cardiac structure and function, especially if structural heart disease is suspected.
4. Exercise Stress Test: Evaluate the heart’s response to stress, which may provoke arrhythmia or other symptoms indicative of coronary artery disease

Sinus rhythm ECG markers of arrhythmia
Electrocardiographic sign	Implication/consideration
Pre-excitation/delta wave	WPW – AVRT
Left atrial enlargement, frequent PACs, sinus bradycardia	Atrial fibrillation
Left ventricular hypertrophy	Atrial fibrillation, ventricular tachycardia
Frequent PVCs	Ventricular tachycardia
Q waves	Ischaemic heart disease – atrial fibrillation, ventricular tachycardia
Widespread T wave inversion across precordial leads, LVH, Q waves and ST-segment changes	Hypertrophic cardiomyopathy – risk of atrial fibrillation, ventricular tachycardia
Long or short QT interval, Brugada pattern, early repolarisation pattern	Genetic arrhythmia syndromes – risk of sudden cardiac death
Inverted T waves or Epsilon waves across right precordial leads (V1–V3)*	ARVC – risk of sudden cardiac death
ARVC arrhythmogenic right ventricular cardiomyopathy; AVRT, atrio-ventricular reciprocating tachycardia; ECG, electrogardiogram; LVH, left ventricular hypertrophy; PACs, premature atrial contractions; PVCs, premature ventricular contractions; WPW, Wolff–Parkinson–White *In patients without right bundle branch block

Ambulatory ECG monitoring: Choice of investigation
Investigation	Investigation of choice: symptom frequency	Advantages	Disadvantages
12-lead ECG	–	Readily available Inexpensive	Rarely performed during arrhythmia
24–48 hour Holter monitor	Daily to every second day	Usually available Does not require activation: asymptomatic arrhythmia can be detected	Low yield other than for daily arrhythmias
Loop/event recorder (range of 1–4 weeks)	Weekly–monthly	Increased yield and cost effectiveness (versus Holter	Most units only record ECG if patient triggered; not useful for asymptomatic arrhythmia or syncope Generally only one-week recorders available Patient discomfort for longer-term monitoring
Loop/event recorder for one week
Implantable loop recorder	Months to year/s	High yield Long-term monitoring approximately three years Automatic bradycardia/ tachycardia storage plus patient-triggered episodes	Cost Not available in all centres Currently only approved for diagnosis of syncope or cryptogenic stroke
Handheld ECG	Months to year	High yield Permanently available to patient	Cost to patient Time for activation of device before arrhythmia termination Potential large volume of data to interpret, no Medicare rebate Data ownership with some systems, sometimes requiring subscription
ECG, electrocardiography

Management Strategies

1. Reassurance and Lifestyle Modification: For benign arrhythmias, such as premature atrial or ventricular contractions.
2. Medication: Antiarrhythmic drugs for more persistent or troublesome arrhythmias.
3. Electrophysiology Study and Ablation: Consider for diagnosing complex arrhythmias or treating them through catheter ablation.
4. Management of Underlying Conditions: Address any identified underlying conditions such as thyroid disorders or electrolyte imbalances.

Referral Criteria

1. Persistent or Severe Symptoms: Refer patients with ongoing or severe symptoms that impact quality of life.
2. Structural Heart Disease: Immediate referral for patients with suspected structural heart disease.
3. High-Risk Cases: Patients with family history of sudden cardiac death or known genetic syndromes affecting the heart.

Which patients to refer or ‘When to worry’

Patients with frequent or persistent palpitations Sustained rapid palpitations Significant associated symptoms: – Pre-syncope/syncope (consider situational context) – Breathlessness – Chest pain Family history of recurrent syncope or of sudden death Significant resting 12-lead electrocardiography or echocardiographic abnormalities – Wolff–Parkinson–White syndrome (pre-excitation including short PR interval and delta wave) – Signs of structural or electrical abnormalities: — T wave abnormalities — Prior myocardial infarction (Q waves) — Long or short QT interval — Brugada pattern — early repolarisation pattern

Benign Early Repolarisation (BER)	is a usually benign ECG pattern producing widespread ST segment elevation commonly seen in young, healthy patients < 50 years of age (rare in those over 70) Also known as “high take-off” or “J-point elevation”, may mimic pericarditis or acute MI Up to 10-15% of ED patients presenting with chest pain will have BER on their ECG
ECG Features of BER	Widespread concave ST elevation, most prominent in the mid-to-left precordial leads (V2-5) Notching or slurring at the J point Prominent, slightly asymmetrical T waves that are concordant with the QRS complex ST elevation : T wave height ratio in V6 < 0.25 (see below) No reciprocal ST depression to suggest Occlusion MI

Follow-Up

1. Regular Monitoring: Depending on the initial findings, some patients may require regular follow-up to monitor the progression of symptoms or response to treatment.
2. Adjustments in Therapy: Based on patient feedback and ongoing symptom monitoring.