BACKGROUNDSignificant Pulmonary Arterial Hypertension (PAH) is a common complication of mitral stenosis. The synthetic sympathomimetic amine dobutamine is a potent β1 receptor agonist with some β2 and α receptor agonistic properties. The net haemodynamic effects with dobutamine are a substantial increase in cardiac output with little or no change in arterial pressure and heart rate. Systemic and pulmonary vascular resistances decrease along with a modest decrease in pulmonary arterial wedge pressure.The aim of this study was to analyse whether dobutamine infusion produces favourable effects on pulmonary vasculature in patients with Mitral Stenosis (MS).