INTRODUCTIONApproximately 50% of inferior wall infarction cases are associated with right ventricular (RV) infarction. 1,2 The incidence of left ventricular (LV) infarction in association with RV infarction ranges from 14% to 84%. [3][4][5] Infarction of the right ventricle alone, on the other hand, is reported in less than 3% of myocardium infarction (MI) cases. 6,7 From an epidemiological point of view, these differences make it diffi cult to accurately evaluate the impact of RV infarction in populations studied.It is the right coronary artery that is most frequently involved, obstructed in its proximal third, thus resulting in dysfunction of the free walls of the right ventricle and the walls of the inferior left ventricle. 8 Although the performance of the right ventricle spontaneously improves even in the absence of coronary reperfusion, its recovery may be slow and may be associated with high rates of atrioventricular conduction, hemodynamic instability and hospital mortality. 9-11 Reperfusion optimizes the recuperation of the right ventricle and improves patients' clinical evolution. 8 The gold standard for the diagnosing of RV infarction is hemodynamic evaluation or an autopsy. It is known that this diagnosis may be made by clinical evaluation, 12,13 electrocardiogram (EKG), hemodynamic evaluation, studies using radioisotopes such as technetium 99m ( 99m Tc) pyrophosphate, and right nuclear ventriculography.EKG using the right V 3 and V 4 (V 3 R and V 4 R) derivations is a simple method presenting good sensitivity and specifi city. 14-17 Identifi cation of right ventricular abnormality, shown by elevation of the ST segment in the right derivations, especially V 4 R, is an important predictor of hospital complications and mortality. 17 It is now known that thrombolytic therapy in patients presenting infarction in