Author + information
- Teewin Rakyhao,
- Nathawut Sibmooh,
- Suporn Chuncharunee,
- Piyamitr Sritara and
- Teerapat Yingchoncharoen
Background: Pulmonary arterial hypertension (PAH) is one of several cardiovascular complications in patients with thalassemia, and significant cause of mortality and morbidity. The etiology is multifactorial and one of the important mechanisms is a decrease in nitric oxide (NO) resulting in vasoconstriction and increase pulmonary arterial pressure. Nitrite anion, a bioactive NO precursor, acts as pulmonary vasodilator in animals. However, the efficacy data of this therapeutic option in thalassemia patients with pulmonary arterial hypertension has never been studied.
Method: Eight hemoglobinE/beta-thalassemia patients with PAH were enrolled in this study. We measured the mean pulmonary arterial pressure (MPAP) and right ventricular systolic pressure (RVSP), using echocardiogram. The MPAP value > 25 mmHg is determined as the presence of PAH. The patients received saline and 15-mg inhaled sodium nitrite via jet nebulizer for 15 min. The primary outcome was the decrease in RVSP measured by echocardiogram during nitrite inhalation. Blood nitrite was measured by chemiluminescence method.
Results: Of 8 thalassemia patients with PAH, the mean age of patients was 46+13 years. The blood nitrite levels (mean + SD) increased from 0.18 + 0.40 to 1.05 + 0.44 µM after inhalation. The mean MPAP was 38.9 mmHg. The mean RVSP at baseline was 67.6 mmHg and significantly lower at 4 min, and 6 min after started giving 15 mg of inhaled nebulized nitrite compare to saline (mean RVSP at 4 min and 6 min vs placebo was 62.3 vs 69.64 mmHg and 62.1 vs 71.2 mmHg, p value 0.031 and 0.045, respectively).
Conclusion: In HbE/beta-thalassemia patients with PAH, giving 15 mg of inhaled sodium nitrite via jet nebulizer significantly decreased pulmonary arterial pressure.
Poster Hall, Hall C
Sunday, March 19, 2017, 9:45 a.m.-10:30 a.m.
Session Title: Advances in Pulmonary Arterial Hypertension
Abstract Category: 35. Pulmonary Hypertension and Pulmonary Thrombo-embolic Disease
Presentation Number: 1269-003
- 2017 American College of Cardiology Foundation