premature atrial contraction


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Related to premature atrial contraction: Premature ventricular contractions

premature atrial contraction

n. Abbr. PAC
An ectopic heartbeat that originates in the atria and precedes a typical atrial contraction.

pre·ma·ture a·tri·al con·trac·tion

(PAC) (prē'mă-chŭr'ā'trē-ăl kŏn-trak'shŭn)
A premature cardiac beat arising from an ectopic atrial focus.
References in periodicals archive ?
For instance, premature atrial contractions, though generally benign, can serve as a trigger for supraventricular tachyarrhythmia as well as they may cause the heart to beat inefficiently and cause symptoms if there frequency exceeds 15-20/minute.11
A Holter monitor demonstrated evidence of increased supraventricular ectopy, with 157 [+ or -] 34 premature atrial contractions per hour during the 3 hr immediately preceding the exposure to GAPs.
Premature supraventricular contractions or premature atrial contractions (PAC).
These changes were, (1) T-wave inversion in anterior or inferior leads or changes of right ventricular hypertrophy in 20(29.41%) patients, (2) a form of arrhythmia in 3 (4.41%) patients-atrial fibrillation with T inversion in inferior leads in 1, paroxysmal supra-ventricular tachycardia and right bundle branch block (RBBB) in 2nd and 1st degree atria ventricular (A-V) block with occasional premature atrial contractions in 3rd, (3) changes suggestive of acute anterior myocardial infarction in 2 (2.94%) patients, (4) 1 patient had S1 Q3 T3 pattern in ECG.
Kwon notes that palpitations may be signs of ectopic heartbeats, such as premature ventricular contractions (PVC) and premature atrial contractions (PAC).
Using 24-hr beat-to-beat electrocardiographic data obtained using a high-resolution Holter system, the researchers sumarized the total number of premature ventricular contractions (PVCs) and premature atrial contractions for each 30-min segment.