PALPITATIONS

SALIENT FEATURES

History

· Are the palpitations regular or irregular'? (Rapid regular rhythms suggest SVT or VT whereas rapid,

irregular rhythms suggest atrial fibrillation, atrial flutter or tachycardia with varying block.)

· ls the onset abrupt (paroxysmal tachyarrhythmias)?

· How frequent are the palpitations'?

· What is the duration of each episode'?

· Is each episode followed by polyuria (seen in supraventricular tachycardia)?

· Is there any relation to exercise (e.g. polymorphic VT in long QT syndrome)?

· What happens on standing (postural hypotension, atrioventricular nodal tachycardia)?

· Are there any precipitating factors such as colIee, tea, alcohol or medications such as thyroid extract,

ephedrine, aminophylline, monoamine oxidase inhibitors?

· Are there any associated symptoms such as chest pain or shortness of breath?

· Is there associated syncope'? (Dizziness or syncope accompanying palpitations should prompt a search

for ventricular tachycardia.)

· Are the palpitations associated with anxiety or panic attacks'? (Anxiety or panic can result in

palpitations.)

Note. Palpitations are a common complaint in up to 16% of outpatients. They are non-specific and in only

15% of patients do they correlate with cardiac arrhythmia.

Examination

· Pulse for arrhythmia.

· JVP is distended in heart failure and 'frog' sign (where prominent jugular venous pulsations match the

rate of tachycardia) in atrioventricular nodal re-entrant tachycardia (l. xmcet 1993; 341: 1254-8).

· Auscultate the heart for murmurs (mitral valve prolapse, valvular heart disease, harsh systolic murmur of

hypertrophic cardiomyopathy), split second heart sound (atrial fibrillation).

· Look for signs of atrial fibrillation.

· Although palpitations may not be present at rest, when the ventricular response is slow, a brisk walk

down the corridor may result in palpitations.

Tell the examiner that you would like to examine the ECG for:

· Presence of Q waves typical of old myocardial infarction, prompting a search for non-sustained

ventricular tachycardia.

· LVH with left atrial enlarg~.ment (as suggested by notched P wave in lead 11 or terminal P wave force in

lead VI more negative than 0.04 s) as this is a likely substrate for atrial fibrillation.

· Short PR interval and delta waves, which suggests ventricular pre-excitation and substrate for SVT

(Wolff-Parkinson-White syndrome).

· Marked left ventricular hypertrophy with deep septal Q waves in I, L and V4 through V6, which suggests

hypertrophic cardiomyopathy.

· Prolonged QT interval and abnormal T wave morphology, suggesting the presence of long QT

syndrome.

· Bradycardias and complete heart block since they may be associated with ventri-cular premature

depolarizations, long QT syndrome and torsade de pointes.

· Abnormal morphology of a ventricular ectopic, suggesting that one of the two types of idiopathic

ventricular tachycardia is present.

DIAGNOSIS

This patient has palpitations (lesion) accompanied by polyuria, indicating a supra-ventricular tachycardia

(aetiology).

QUESTIONS

What are the causes?

· Extrasystole.

· Tachycardia or bradycardia.

· Drugs (see above).

· Other: thyrotoxicosis, hypoglycaemia, unaccustomed exertion, phaeochromo-cytoma, fever.

· Anxiety state (also known as da Costa's syndrome or cardiac neurosis).

How would you investigate a patient suspected of having a disorder of cardiac rhythm ?

· 12-lead ECG (look tk)r evidence of a rhythm disturbance and pre-excitation syndrome).

· Continuous ambulatory (Holter) echocardiography (many patients with pal-pitations may have stable

sinus rhythm).

· Exercise ECG.

J.M. da Costa (1833-1900) was Professor of Medicine at Jefferson Medical College, Philadelphia.