We report the case of a 55-year-old male who came to the emergency for an oppressing retrosternal thoracic pain worsening after the physical effort, he had a medical history of dyslipidemia. The general and cardiovascular examinations were normals.in front of that, we realized an ECG who finds an irregular sinus rhythm, A Q wave of necrosis in the lower territory (D2, D3, AFV) was present in an association of an atrioventricular block (AVB) classified 2^nd-degree Mobitz 2, 2/1 (A). The atrioventricular block is a conduction disorder between the atria and the ventricles sit at the level of the atrioventricular node. in sinus rhythm, the blocking of atrioventricular conduction is variable with a simple lengthening of the PR interval to, one, several, or all blocked P waves. the degree of the block is proportional to the frequency of the auricles. Atrioventricular block (AVB) 2^nd degree Mobitz 2, 2/1 is defined by a constant PR space, a P/QRS ratio equal to 2. It complicates a lower infarction following the obstruction of the left retro ventricular artery which arises from the right coronary artery which vascularizes the atrial ventricular node. AVB conduction disorder in the lower post-infarction is most often spontaneously resolved within a few days. If treatment is indicated, it generally responds well atropine 0.5 to 1 mg using a slow intravenous route to repeat if necessary without exceeding 3 mg.

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Corresponding author
Najlaa Salmi, Cardiology Department University Hospital Ibn Sina of Rabat, Rabat, Morocco (salminajlaa2608@gmail.com)