Iron deficiency in pulmonary arterial hypertension associated with congenital heart disease.

OBJECTIVES

We aimed to investigate the prevalence of iron deficiency (ID) in congenital heart disease associated with pulmonary arterial hypertension (CHD-PAH) and to explore the influence of ID on CHD-PAH patients. What was associated with ID in these patients was also looked into.

DESIGN

One hundred and fifty-three patients who were newly diagnosed with CHD-PAH were enrolled. Patients were divided into iron-deficient and iron-replete groups according to the following criteria. ID was defined as transferrin saturation <20% in male and transferrin saturation <25% in female. Clinical data of all participants were collected and compared. Logistic regression was performed to explore factors associated with ID in CHD-PAH.

RESULTS

Thirty-nine percent of 153 CHD-PAH patients were founded with ID. Iron-deficient group had greater proportion of female patients, shorter six minutes walking distance (6-MWD), higher N-terminal pro-brain natriuretic peptide levels, lower creatinine levels, greater ratio of diastolic right ventricle diameter to left ventricle diameter. Female (OR = 15.44, 95%CI 4.91-48.54, p < .01), 6-MWD (OR = 0.99, 95%CI 0.98-1.00, p = .02) and mean right atrial pressure (OR = 1.13, 95%CI 1.02-1.26, p = .02) were independently associated with ID in the overall CHD-PAH patients. Menstruation was independently associated with ID in the female subgroup (OR = 3.88, 95%CI 1.09-13.84, p = .04).

CONCLUSIONS

ID was highly prevalent in CHD-PAH patients. Worse exercise tolerance and right heart function were observed in iron-deficient patients with CHD-PAH. Female, 6-MWD, mean right atrial pressure and menstruation are important variables indicating the presence of ID in CHD-PAH.