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Definition
It is essentially an atrial disturhance due to multiple ectopic foci causing an absolutely irregular ventricular response
affecting the pulse in its rate, rhythm and volume so that no two heats are equal That is why this condition is also called “delirium cordis”, ie heart in a state of delirium It is the commonest chronic arrhythmia Mechanism
l.Focal irritation with discharge
2.Re-entry or reciprocal mechanism
Cireus movement and Prinzmetal’s theory were put forwarded to explain this cardiac arrhythmia. The atrial pulsation varies from 400 to 600 per minute but the ventricles only respond to about 80 to 180 beats per minute, while the pulse beal varies from 100 to 120 per minute, therefore a pulse.deficit always exists (usually more than 20 beats per minute).Aetiology
1. Rheumatic heart disease, commonly mitral stenosis, other non-rheumatic valvular heart disease
2. Endocrinopathies particularly thyrotoxicosis, others include
hypothyroidism, phaeochromocytoma.
3. Ischaemic heart disease with or without myocardial
Fig. 1.43. ECG showing Atrial fibillarion with Rapid, irregular S wa
infarction e.g. coronary sclerosis or coronary thrombosis.
4. Hypertensive heart disease
5. Other cardiac conditions like cardiac surgery, particularly
atriotomy, pulmonary embolism, endocarditis, dilated
cardiomyopathy. ASD, mitral valve prolapse, etc
6. Drugs, e.g. Emetine, Aconite, Digitalis in toxic doses,
alcohol excess or alcohol withdrawal ar even small amount
of alcohol consumption (Holiday heart). Theophy lline. B-
adrenergic agonist.
7. Acute febrile diseases with associated carditis, eg
diphtheria, acute rheumatic fever, pneumonia ete
8. Septic foci e g acute appendicitis, subdiaphragmatic
abscess, etc. But these are very rare
9. Disease or conditions where pericardium is involved, e g
constrictive pericarditis, bronchogenic carcinoma involving
the pericardium or operations on the pericardium

Aetiology Same as Atrial Fibrillation, but common with COPD. Mechanism Same as Atrial Fibrillation but the ectopic atrial impulse formation occurs at the rate of 250-350 per minute. Since AV node cannot transmit more than 210-220 impulses there is aphysiological AV block (2 1). Incidence is far less common than fibrillation.Atrial flutter results from a single re-entrant circuitsurrounding a structural or functional conduction barrier in the atrial musculatureSymptoms
1. Palpitation.
2. Breathlessness.
3. Pain chest.
Signs Flutter should be suspected when pulse is regular at a rate of 120-170 per minute and is not influenced by change of
posture, exercise and emotional upsets, i.e., it becomes a fixed pulse. Sometimes flutter waves may be seen in the jugular
veins. Pulse rate may vary from time to time depending on the degree of AV block. When the ventricular rate is 75 per
minute exercise may double the rate. Carotid massage maycause change in the AV block and thereby slowing of the
ventricular rate. Pulse deficit is absent Investigations ECG shows rapid regular F (flutter) waves giving rise to a saw tooth appearance which is well visualized in lead VI and sometimes in oesophageal leads Fig. 1.45. Atrial flutter showiIn typical atrial flutter, flutter waves are positive in Vi but negative in II, III and aVF. Flutter and fibrillation may co-exit together which is called Flutter fibrillation or impure flutter Treatment Paroxysmal and recent onset atrial flutter Electrical cardioversion with less than 50J is helpful and is the treatment of choice. Verapamil may also slow the ventricular rate transiently but a combination of Digitalis and Quinidine may revert the flutter to sinus rhythm. Digitalisation should not be done when DC shock is planned. Digitalis may be used as a second choice drug. Intravenous
Digitalis should be used Right atrial pacing or transvenous pacing may also be done. Chronic and persistent atrial flutter
Digitalis is the drug of choice. The dose of Digitalis is more than is used conventionally. Propranolol or Verapamil may be used
when Digitalis fails. Quinidine should not be used because of the danger of 1 1 conduction; but may be used in conjunction with
Digitalis. In case of refractorý atrial flutter radiofrequency ablation within the atrium to interrupt the circuit may be done. Kleiger, R. and Lown, B. (1966) Cardioversion and digitalis- Clinical Studies. Circualation 33: 878 Liberthson, R. R. et al (1976) Atrial tachyarrhythmias in acute myocardial infarction. Am. J. Med. 60: 956 Niebauer, M. J er al. (2001). Management of atrial lutter. Cardiol. Riv. 9 253 Olshansky. Becterial (1992) Arrial flutter update on the mechanism treatment. 15 2308
nd P. (1973) Cardiac arrhythmias, Haemodynamic sequelae.

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