Fractional exhaled nitric oxide in adult congenital heart disease

Background Fractional exhaled nitric oxide levels are related to various clinical diseases. This study investigated the associations between the clinical characteristics and the level of fractional exhaled nitric oxide in patients with adult congenital heart disease. Methods and results Fractional exhaled nitric oxide values were measured in 30 adult patients with stable congenital heart disease who had undergone right heart catheterization and 17 healthy individuals (controls). There was no significant difference in fractional exhaled nitric oxide values between patients with congenital heart disease and healthy controls. Depending on whether their fractional exhaled nitric oxide values were above or below the median value, patients with congenital heart disease were divided into two groups (low vs. high fractional exhaled nitric oxide groups). The relationship between fractional exhaled nitric oxide values and clinical characteristics was investigated. There was a higher percentage of patients with cyanosis in the low fractional exhaled nitric oxide group (50%) than in the high fractional exhaled nitric oxide group (7.1%). There was no significant difference in right heart catheterization data between the low and high fractional exhaled nitric oxide groups. The fractional exhaled nitric oxide value was correlated to the number of neutrophils in patients with cyanosis (r = 0.84 (N = 8), p = 0.005). Conclusions In this cohort of patients with adult congenital heart disease, lower levels of fractional exhaled nitric oxide corresponded to the presence of cyanosis.