Palpitations: History Taking and Differential Diagnoses

History of Presenting Complaint

Overview

With each symptom, always (if relevant) ask about:

• When did it start?
• Did it come on suddenly or gradually?
• Is it continuous or intermittent?
• Has this ever happened before?

Palpitations

• Character:
  • What do they feel like? (e.g. pounding/fluttering etc.)
• Timeline:
  • How long have they been ongoing?
  • How often do episodes happen? (If relevant)
• Exacerbating/relieving factors:
  • Does anything trigger them? (e.g. coffee/alcohol)
  • Does anything help with relieving them?

Review of systems

• Screen for cardiovascular disorders and syncope:
  • Chest pain, shortness of breath, cough
  • Dizziness, fainting, loss of consciousness
• Screen for hypoglycaemia:
  • Hunger, sweating, anxiety
  • Do they use insulin?
• Screen for anaemia:
  • Fatigue, lethargy, shortness of breath on exertion
• Screen for general red flags:
  • Unexplained weight loss, night sweats, or fevers
• Screen for hyperthyroidism:
  • Diarrhoea, agitation, sweating, heat intolerance, anxiety, eye problems
• Screen for anxiety:
  • Tingling, headaches, nausea, feeling like they’re ‘going to die’

Past Medical History

Questions include:

• Do they have any other medical conditions?
• Do they have any risk factors for cardiac disease?
  • Coronary heart disease, angina, myocardial infarction?
  • Stroke, deep vein thrombosis, pulmonary embolism?
  • High blood pressure?
  • Diabetes mellitus?
• Have they ever had any previous surgery?
• Do they take any regular medications?
• Do they take any over-the-counter medications, herbal remedies, or supplements?

Family History

• Is there any family history of anything similar?
• Any family history of heart problems or sudden death?

Allergy History

• Are they allergic to anything?
• What happens during the allergic reaction?

Social History

• Do they smoke?
  • If so, how much and how long?
• Do they drink alcohol?
  • If so, how much and how long?
• Do they use any illicit drugs?
  • If so, how much and how long?
• Do they drink caffeine?
• What is their occupation?
• Who’s at home?
• What support do they have?
• How has this impacted their activities of daily living?
• Has there been any recent foreign travel?

Investigations

When suggesting investigations in an OSCE, the BOXES (Blood tests, orifice tests, x-rays, ECGs, special tests) mnemonic is useful for deciding the order of investigations:

• Blood tests:
  • Blood glucose:
    • May show hypoglycaemia which can cause palpitations
  • Full blood count:
    • May show anaemia which can cause palpitations
  • Thyroid function tests (TFTs):
    • May show thyrotoxicosis which can cause palpitations
  • Urea and electrolytes (U&Es):
    • May show electrolyte abnormalities (e.g. hypo-/hyperkalaemia) which can cause arrhythmia
  • Calcium and magnesium:
    • Low calcium and magnesium can cause long QT syndrome which can lead to polymorphic ventricular tachycardia (torsades de pointes) 
• ECGs:
  • ECG:
    • May show a characteristic arrhythmia (e.g. atrial fibrillation
• Special tests:
  • Ambulatory ECG monitoring (Holter monitoring):
    • May capture arrhythmia
  • Echocardiography:
    • May identify structural heart disease (e.g. hypertrophic obstructive cardiomyopathy, HOCM)

Differential Diagnoses

Atrial fibrillation

• A history may reveal:
  • A history of cardiovascular disease (e.g. heart failure, ischaemic heart disease)
  • A history of thyrotoxicosis
• A physical exam may reveal:
  • An irregularly irregular heartbeat
• Investigations may reveal:
  • ECG:
    • Irregularly irregular rhythm without discrete P waves
    • Ambulatory ECG monitoring may be needed if the ECG does not identify the arrhythmia

Paroxysmal supraventricular tachycardia

• A history may reveal:
  • Palpitations that suddenly start and go
  • Palpitations may be relieved with Valsalva manoeuvres (e.g. blowing against resistance or straining)
• A physical exam may reveal:
  • A rapid and fluttering pulse
• Investigations may reveal:
  • ECG:
    • Narrow QRS tachycardia
    • Ambulatory ECG monitoring may be needed if the ECG does not identify the arrhythmia

Ventricular tachycardia

• A history may reveal:
  • Chest pain, shortness of breath, sweating, anxiety, pre-syncope, cold peripheries
  • A history of cardiac disease (e.g. ischaemic heart disease or heart failure)
• A physical exam may reveal:
  • Tachycardia and hypotension
• Investigations may reveal:
  • ECG:
    • Broad-complex tachycardia
    • Ambulatory ECG monitoring may be needed if the ECG does not identify the arrhythmia
  • The patient may be peri-arrest

Anxiety/panic disorder

• A history may reveal:
  • Tingling, paraesthesias, a feeling like they’re ‘going to die’, stress
• A physical exam may reveal:
  • n/a
  • May show tachycardia
• Investigations may reveal:
  • ECG:
    • Sinus tachycardia

Hypoglycaemia

• A history may reveal:
  • Insulin use, alcohol consumption, long periods without eating
  • Anxiety, nausea, hunger, jittering, tremors, dizziness, vision changes, weakness, seizures
• Investigations may reveal:
  • Blood glucose:
    • Low

Hyperthyroidism

• A history may reveal:
  • Weight loss, heat intolerance, sweating, anxiety, diarrhoea, oligomenorrhoea, eye problems
• A physical exam may reveal:
  • Tachycardia, fine tremor, goitre, irregularly irregular pulse, hyperreflexia, pretibial myxoedema, exophthalmos 
• Investigations may reveal:
  • ECG:
    • May show sinus tachycardia or atrial fibrillation
  • TFTs:
    • Low TSH and elevated T4 and T3

Fever

• A history may reveal:
  • Sweating, cold intolerance, shivers, features of an underlying infection
• A physical exam may reveal:
  • Fever
• Investigations may reveal:
  • Depends on underlying cause

Excess alcohol

• A history may reveal:
  • An episode of binge drinking
  • ‘Holiday heart syndrome’ – irregular heartbeat associated with high levels of alcohol consumption 
• A physical exam may reveal:
  • Irregularly irregular pulse
  • Features of alcohol intoxication
• Investigations may reveal:
  • ECG:
    • May show atrial fibrillation

Excess caffeine

• A history may reveal:
• Palpitations occur in correlation to caffeine consumption
• Large amounts of caffeine ingested

Hypertrophic obstructive cardiomyopathy (HOCM)

• A history may reveal:
  • A family history of sudden cardiac death
  • Shortness of breath on exertion, syncope or near-syncope on exertion
• A physical exam may reveal:
  • Ejection systolic crescendo-decrescendo murmur in the right upper sternal border – louder with Valsalva manoeuvre and quieter with squatting
  • S4 heart sound may be heard
• Investigations may reveal:
  • ECG:
    • May show deep Q waves and left ventricular hypertrophy
  • Echocardiography – MR SAM ASH:
    • MR – mitral regurgitation
    • SAM – systolic anterior movement of the anterior mitral valve leaflet
    • ASH – asymmetrical hypertrophy

Anaemia

• A history may reveal:
  • Fatigue, shortness of breath on exertion, pallor
  • Chronic kidney disease or another chronic comorbidity 
• A physical exam may reveal:
  • Conjunctival pallor, glossitis, hair loss, atrophic glossitis, koilonychia
• Investigations may reveal:
  • Full blood count:
    • Low haemoglobin
    • Haematinics including B12, folate, and iron studies can help identify the underlying cause

Phaeochromocytoma

• A history may reveal:
  • Flushing, headaches, anxiety, panic-attack-like symptoms with palpitations
• A physical exam may reveal:
  • Hypertension and tachycardia
• Investigations may reveal:
  • ECG:
    • May show sinus tachycardia
  • 24-hour urinary metanephrines:
    • Diagnostic test

Hyperkalaemia

• A history may reveal:
  • Acute kidney injury, chronic kidney disease, drugs (ACE inhibitors, angiotensin II receptor blockers, spironolactone), Addison’s disease, rhabdomyolysis
• Investigations may reveal:
  • ECG:
    • May show peaked or tall-tented T waves
    • May show loss of P waves and broad QRS complexes

Wolff-Parkinson-White syndrome (WPW)

• A history may reveal:
  • Palpitations that can be terminated with Valsalva manoeuvres
  • A family history of sudden cardiac death
• A physical exam may reveal:
  • Tachycardia
• Investigations may reveal:
  • ECG:
    • May show a short PR interval and a delta wave (slurred upstroke of QRS complex)
  • Ambulatory ECG monitoring may be needed if the ECG does not identify the arrhythmia

Premature ventricular beats

• A history may reveal:
  • Palpitations described as a missed beat followed by a heavier pounding beat, may be associated with caffeine
• Investigations may reveal:
  • ECG:
    • May be normal, may show wide QRS complexes
  • Echocardiography:
    • Normal

Drug-induced palpitations

• A history may reveal:
  • Stimulants, drugs that lengthen the QT interval (sotalol, tricyclic antidepressants, citalopram, macrolide antibiotics – particularly erythromycin), drugs affecting electrolytes (e.g. thiazide-like and loop diuretics)
• Investigations may reveal:
  • ECG:
    • May show changes associated with the suspected drug
  • U&Es:
    • May be deranged, such as if diuretics have been used