90 Quantification of Pulmonary Artery Calcium Deposits in Patients With Primary and Secondary Pulmonary Hypertension Using Computed Tomography.

Abstract

ObjectivesTo quantify calcium (Ca) deposition in pulmonary arterial (PA) circulation in patients with primary pulmonary hypertension (PPH), Eisenmenger syndrome (ES), and atrial septal defect (ASD) without pulmonary hypertension (PH) using computed tomography (CT) scans.BackgroundCT readily quantifies Ca deposits. PA Ca deposits have been identified in ES and PPH patients. Histopathological staining of deposits revealed typical lipid-rich atherosclerotic plaques and fibrous intimal deposits. Within the PA tree, Ca deposition has not been quantified and causes are not well understood. The role of PA hypertension in promoting this process is unclear. PA oxygen saturation in ES patients is elevated in infancy and then reduced as large shunting lesions develop systemic levels of pulmonary resistance and reverse their shunt. PA oxygen saturation in PPH patients is similar to patients without organic heart disease. Oxygen saturation in ASD patients without PH is elevated. We sought to quantify the Ca in PA circulation of ES, PPH, and ASD without PH patients using CT. ES patients represent initially elevated PH, then reduced PA oxygen tension. PPH patients have PH and PA normoxia. ASD patients have PA hyperoxia and minimal PH.Methods12 ES patients (mean age 42, range 22-60), 10 PPH patients (mean age 45, range 26-75), and 6 ASD without PH patients (mean age 41, range 24-59) were included. PA pressures ware measured by cardiac catheterization or echocardiography and were at systemic levels in ES and PPH. CTs were analyzed for PA Ca content. Differences between mean PA Agatston (Ag) Ca scores were bootstrapped and t-test was performed for raw scores and scores with adjusted means. Correlation coefficient was used to determine the relationship between Ag score and age in patients with ES.ResultsMean Ag Ca score for patients with ES was 4,729 (range 15-31,609, SD ± 9589), PPH 181.9 (range 0-1,324, SD ± 4,147, p = .065), and ASD without PH 0.9 (range 0-5.6, SD ± 5.6, p = .035). Age was correlated with Ag score in ES patients (r = .63, p = .01). Excluding the oldest ES and PPH patients and counting both ASD and PPH, mean Ag score for ES was 470.6 compared to 202.1 for PPH (p = .038). ASD without PH patients had the lowest Ca score (p = .035 versus PPH and ES).ConclusionsPA Ca deposits are elevated in ES patients compared to PPH and ASD without PH. ASD without PH patients had the least PA Ca. PH and altered oxygen saturation in ES patients are associated with increased Ca deposits in the PA circulation as compared to PH or hyperoxia alone. Ca deposited in PA circulation increases with age in ES patients.