Abstract
Background and aim: Thoracic aortic aneurysm and pulmonary hypertension are relatively common diseases but the related geometric mechanism is poorly investigated. Our aim was to assess the heritable affects on the diameter of ascendent aorta (AAd), right and left pulmonary arteries (RPAd, LPAd), and main pulmonary artery (MPAd), and the ratio of the diameter of the pulmonary artery to the diameter of the aorta (PA:A ratio) within a sample of Hungarian twins.
Methods and Materials: 52 Hungarian (26 monozygotic /MZ/ and 26 dizygotic /DZ/) healthy twin pairs (mean age 56±8 years) recruited from the Hungarian Twin Registry underwent computed tomography (Brilliance iCT, Philips Healthcare, Best, The Netherlands) coronarography. Unenhanced and contrast enhanced CT images were analyzed retrospectively to calculate the investigated geometric parameters. All phenotypic variables were screened for outliers and normality. Concordance between MZ and DZ pairs were assessed by Pearson correlations. Rough heritability was calculated according to the Falconer's formula.
Results: Mean AAd, RPAd, LPAd, MPAd and PA:A ratio indicated 30±4 mm, 18±3 mm, 19±3 mm, 23±3 mm and 0,8±0,1, respectively. A high heritability was found in case of AAd, RPAd, LPAd, MPAd and PA:A ratio (0,62, 0,63, 0,82, 0,81 and 0,75).
Conclusions: This classical twin study has demonstrated that the geometry of ascendent aorta, pulmonary artery and their ratio has a strong heritability. In order to quantify the relative influence of additive genetic, common environmental and unique environmental effects on the twin pairs further investigation is warranted.
- © 2014 ERS