We describe an adult patient who presented with purulent pericarditis in whom two-dimensional transthoracic echocardiography demonstrated a marked decrease in the area of the right ventricular wall together with the overlying fibrin following intrapericardial administration of a fibrinolytic agent. Documentation of this decrease by measurements performed and illustrated on two-dimensional images have not been reported previously in an adult patient with purulent pericarditis, to the best of our knowledge.