Background: There has been a renewed interest in nitric oxide donor drugs, such as nitroglycerin, delivered by the inhalational route for treatment of pulmonary arterial hypertension (PAH). We investigated the acute effects of inhaled nitroglycerin on pulmonary and systemic haemodynamics in children with PAH associated with congenital heart disease.
Methods: Nineteen children with acyanotic congenital heart disease and a left to right shunt with severe PAH, undergoing routine diagnostic cardiac catheterization were included in this study. Systolic, diastolic and mean systemic as well as pulmonary artery pressures, right atrial pressure and pulmonary capillary wedge pressure (PCWP) were recorded and systemic vascular resistance index (SVRI) and pulmonary vascular resistance index (PVRI) were calculated at room air, following 100% oxygen as well as after nitroglycerin inhalation in all patients.
Results: Systolic, diastolic and mean pulmonary artery pressure and PVRI decreased significantly, whereas heart rate, systolic, diastolic and mean systemic arterial pressure, PCWP and SVRI did not change significantly following 100% oxygen or inhalation of nitroglycerin.
Conclusion: Inhaled nitroglycerin significantly decreases systolic, diastolic and mean pulmonary artery pressure as well as PVRI without affecting systemic haemodynamics, and thus can be used as a therapeutic modality for acute reduction of PAH in children with congenital heart disease.