Atrial arrhythmias are heart rhythm disorders in which the producingÂ mechanism is in the atria or the sinus node or in an ectopic focus located outside the sinus node or occur through a reentry mechanism at this level.
AtrialÂ extrasystolesare premature contractions of the heartÂ and are produced by impulses coming from ectopic focus located in the walls of the atria. Ectopic impulses activate the atria in differentÂ ways than the sinus impulse, which reflect different P waves on the electrocardiogram.
Atrial extrasystoles may occur in people withÂ a healthy heartÂ (ifÂ so theyÂ do not have a pathological significance), in patients with heart disease (ischemic heart disease, heart failure) in patients with COPD and hypoxemia (due to hypertension of theÂ small circulation) and in patients with hyperthyroidism.Â Atrial extrasystolesÂ can precede the installation of supraventricular (atrial) tachycardias, flutter and atrial fibrillation, especially in chronic forms.
DigitalisÂ intoxicationÂ canÂ be also the cause and can frequently announce the Â installation of an atrial tachycardia with block. In myocardial infarction, atrial extrasystoles may be a sign of atrial infarct. Emotion, fatigue, coffee, tobacco, are precipitating factors of atrial extrasystoles, especially in healthy individuals.
Atrial extrasystoles are generally asymptomatic, symptoms usually are resumed to a feeling of discomfort in the chest which isÂ quite annoying, and palpitations. When they occur inÂ bursts they areÂ accompanied by paleness, anxiety, sweating, fainting, and even shortness of breath. Physical signs consist of irregularÂ peripheral pulseÂ andÂ abnormal heartbeat succession.
Atrial extrasystoles causes:
- Atrial extrasystoles may occur in normal people without any patologic semnification. The risk of havingÂ atrial extrasystoles increases with age.
- Heart disease like Â myocardial ischemia (angina pectoris), myocarditis (heart muscle inflammation), dilated or hypertrophic cardiomyopathy, mitral valve prolapse
- Metabolic Disorders like hypokalemia (low potassium levelsÂ in the blood), hypoxia (low oxygen levels in blood), hypomagnesaemia (low amount of magnesium in the blood), hypercalcemia.
- Endocrine: hyperthyroidism ( secretion of thyroid hormones is increased)
- Medications: digoxin, theophylline, tricyclic antidepressants
- DifferentÂ exciting substance abuse like coffee, tea, alcohol, cocaine, amphetamines
- Acute infection
- Hiatal hernia (herniationÂ of the upper part of the stomach intoÂ the chest cavity)
- After surgery