Author + information
- Azar Hussain,
- Rob Bennett,
- Zaheer Tahir,
- Mubarak Chaudhry,
- Alyn Morice and
- Loubani Mahmoud
Background: The prostacyclin analogues and phosphodiesterase inhibitors are commonly used to treat pulmonary hypertension. The aim of this study was to characterize the pharmacological effects of clinically used prostacyclin analogues on the human pulmonary vasculature in comparison to phosphodiesterase 3 and 5 inhibitors.
Methods: Forty pulmonary artery rings of internal diameter 2-4 mm and 2 mm long, mounted in multiwire myograph system, were used for measuring changes in isometric tension. Concentration response curves were constructed to Epoprostenol, Iloprost, Sildenafil and Milrinone by cumulative addition to the myograph chambers.
Results: The Epoprostenol (Ep), Iloprost (Ip), Sildenafil (Sd) and Milrinone (Ml) caused dose-dependent vasodilation in the pulmonary artery (EC50 29.4nM, 1.43nM, 979nM and 1.01uM respectively). The order of efficacy was Ip > Ep > Ml > Sd and the order of potency was Ip > Ep > Sd > Ml. Simultaneous administration of Iloprost and Milrinone does not have an additive vasodilation response.
Conclusions: This study demonstrated the efficacy and potency of clinically used prostacyclin analogues and phosphodiesterase inhibitors on human pulmonary vascular reactivity with Epoprostenol and Iloprost causing maximal dilatation while Sildenafil and Milrinone had less effect. These effects may need to be taken into account in the clinical setting as prostacyclin analogues provide better results.
Poster Hall, Hall C
Saturday, March 18, 2017, 9:45 a.m.-10:30 a.m.
Session Title: Understanding Pulmonary Vascular Disease: From Bench to Bedside
Abstract Category: 35. Pulmonary Hypertension and Pulmonary Thrombo-embolic Disease
Presentation Number: 1181-008
- 2017 American College of Cardiology Foundation