Background: Right ventricular (RV) affection in acute left ventricular (LV) myocardial infarction (MI) is frequently underestimated in the clinical setting as the diagnostic limitations of the electrocardiogram and echocardiography. Objective: To assess RV function in patients presented with first acute anterior ST elevation myocardial infarction (STEMI) who underwent successful primary percutaneous coronary intervention (PCI) and factors affecting it. Patients and Methods: Forty consecutive patients with anterior STEMI who underwent successful primary PCI in the Cathetrization (cath) labs of Al-Azhar University Hospitals, Cairo, Egypt from March 2019 to April 2020 for first acute anterior STEMI without RV were enrolled in the study. Presence of a coexisting clinical condition that might affect RV function, patients with RV infarction or those having significant stenosis (>50%) affecting RV branch or right coronary artery proximal to RV branch were excluded. Echocardiography was performed during the hospital stay to assess the LV and RV systolic and diastolic functions  with special focus on tricuspid annular plane systolic excursion, mid RV end-diastolic dimension, right atrial area, RV fractional area change, and tissue Doppler-derived myocardial performance index. Results: RV dysfunction, according to our definition in the first anterior MI, occurred in (55%) of the study population. Independent predictors for abnormal RV function were left circumflex artery mid or proximal affection, eventful procedure, occurrence of no reflow, glucose level, LV end-systolic dimension, LV end-diastolic dimension, and LV ejection fraction. Conclusion: RV dysfunction is detected in anterior myocardial infarction after successful revascularization. Several echocardiographic parameters may be possible measures for RV dysfunction including RVFAC, TAPSI, MPI and S'.