Polycythemia hyperviscosity syndrome has been associated with multiple systemic effects. There is dearth of data on the effects of polycythemia on cardiac function. This case presents a newborn infant with symptomatic polycythemia in whom detailed myocardial function analysis for systolic and diastolic performance, as well as end-organ perfusion assessment was carried out using transthoracic echocardiography. Hemodynamic information in polycythemic infants before and after partial exchange could improve our understanding of the impact on myocardial performance.