Abstract
The patent ductus arteriosus (PDA) has diverse clinical and hemodynamic manifestations depending on its size and the degree of the ensuing left-to-right shunt. A small PDA that causes minor shunting has no major hemodynamic consequences. Conversely, a large PDA with a significant left-to-right shunt may lead to various hemodynamic abnormalities. These include left-sided volume overload that may result in heart failure and/or pulmonary hypertension, the latter being a flow-dependent and mostly reversible phenomenon. The most feared complication is the development of severe and irreversible pulmonary hypertension (Eisenmenger physiology). In this manuscript, we provide examples of the various hemodynamic profiles of PDA as assessed by echocardiography in the adult population.