Is to analyze the incidence and predictors of developing AF in patients with inferior infarction who undergo PCI with and without atrial and SN branches occlusion

Atrial fibrillation (AF) occurs in 5% to 18% of patient with acute ST-segment elevation myocardial infarctions (STEMIs) and 4.5% in patients with STEMI treated with percutaneous coronary intervention (PCI).

Diagnosis of AF in acute myocardial infarction (AMI) patients is important because it increases the risk of cardiovascular event and associated with increased in-hospital and long term rates . Atrial ischemia/infarction translates into P Q segment depression or elevation on the electrocardiogram and often associates with atrial tachyarrhythmias .

Side-branch obstruction is one of the adverse effects of PCI the location of the culprit vessel also affects the occurrence of AF in AMI Atrial arteries arise from the right coronary artery (RCA) and circumflex coronary artery (CX) and extend through the atrial myocardium to supply both chambers It is therefore conceivable that PCI of lesions located at the RCA and CX could lead to an accidental atrial branch occlusion .

Atrial myocardial ischemia secondary to atrial branches occlusion (ABO) might lead to mechanical atrial dysfunction, increased electrical vulnerability to atrial arrhythmias, and late structural remodeling .

The sino nodal (SN) artery originates from the proximal portion of the RCA in about 60% of humans Side branch occlusion of the SN artery occurring accidentally during PCI for proximal RCA lesions would provide an opportunity to produces SN dysfunction in humans. Uptill now , there have been no systematic studies concerning SN dysfunction caused by side-branch occlusion of the SN artery during PCI .

Left atrial volume seems to be a strong predictor of incident of AF , with increase in left atrial filling pressures, atrial stretch and enlargement of the chamber occur, leading to remodeling of the structure, physiologic properties, and electrical milieu of the left atrium, culminating in the development of AF

Inclusion Criteria:

• Patients with inferior STEMI who will undergo PPCI (primary percutaneous coronary intervention )

Exclusion Criteria:

• -A history of preexisting AF
• Prior documentation of heart failure or reduced left ventricular ejection fraction < 50%,
• Severe valvular disease ( rheumatic , sclerotic ) or secondary to AMI
• Left ventricular hypertrophy : enlargement and thickening of the walls of the ventricle
• Patients with inferior STEMI treated with intravenous thrombolysis or conservative strategy
• Patients with inferior STEMI who undergo primary PCI and associated with right ventricular or posterior infarction
• History of pulmonary embolism or COPD ( chronic obstructive pulmonary disease )
• Those with thyrotoxicosis

patients with inferior S-T elevation myocardial infarction