The ascending aorta and left ventricular outflow tract (LVOT) have different diseases and embryologic origins and are spatially complicated. The genetics of thoracic aortic diameter in a single plane was previously studied. For a study, researchers aimed to highlight the genetic underpinnings of LVOT, aortic root, and ascending aorta diameter.

Using deep learning, they examined 2.3 million cardiac magnetic resonance pictures from 43,317 UK Biobank members. They measured the LVOT, the aortic root, and 6 points along the ascending aorta to determine their diameters. They performed a genome-wide association investigation and produced a polygenic score for each diameter. Finally, they looked at links between these scores and the occurrence of diseases.

At least 1 diameter was substantially related to 79 different loci. About 35 of these were brand-new, and the majority of them were connected to 1 or 2 diameters. The strongest polygenic score that accurately predicted a thoracic aortic aneurysm was an aortic diameter of 13 mm from the sinotubular junction (n=427,016; mean HR: 1.42 per SD; 95% CI: 1.34-1.50; P=6.67×10−21). Aortic stenosis was predicted by a polygenic score that predicted a smaller aortic root (n = 426,502; mean HR: 1.08 per SD; 95% CI: 1.03-1.12; P=5×10−6).

They found unique genetic loci underlying the LVOT, aortic root, and various ascending aorta segment sizes. They pinpointed a section of the aorta whose genetics may be particularly useful in determining the likelihood of developing a thoracic aortic aneurysm. They also outlined a genetic profile that could be predisposed to aortic stenosis. Identifying those at risk for aortic illness and selecting therapeutic targets may be easier with an understanding of genetic contributions to proximal aortic diameter.

Reference: jacc.org/doi/10.1016/j.jacc.2022.05.024