Approach to Atrial Arrhythmias in ACS

Atrial arrhythmias are frequent during and after acute coronary syndromes (ACS) and usually complicate the course of disease. Occurrence of some of these arrhythmias is a sign of poor prognosis. If we don’t consider sinus tachycardia and bradycardia as atrial disturbances, atrial fibrillation (AF) is the most prevalent of supraventricular arrhythmia in ACS. Its incidence is reported to be 2.3 – 21% after myocardial infarction (MI). Important considerations and approaches regarding to AF are its diagnosis, treatment strategies, anticoagulation and lifelong stoke prevention. Although atrial premature beats are prevalent during ACS but their occurrence don’t have important prognostic implications. Other supraventricular disturbances during ACS are conduction disorders. Atrioventricular conduction disturbances are well-known complications of acute MI which need prompt attention. Myocardial ischemia or necrosis may cause bundle branch block. Atrioventricular node artery originates in 90% from right coronary artery (RCA). Septal branches of left anterior descending coronary artery (LAD) supplies right bundle branch and left anterior fascicle of left bundle branch in 90% of cases. Posterior fascicle of left bundle branch supplies from conus branch of RCA. Therefore, occlusion of LAD may cause right bundle branch block or left anterior fascicular block. Atrioventricular block in inferior MI is above His bundle in more than 90% of cases with narrow QRS, junctional scape rhythm and moderate bradycardia. In anterior MI there are necrosis of bundle branches and is located down to bundle of His. In this type block QRS has RBBB morphology and extreme axis deviation. Prompt assessment for temporary or permanent pacemaker implantation is mandatory

کلیدواژه ها:

Acute coronary syndrome ، Atrial arrhythmias ، Electrical Complications