Genome-wide association meta-analysis identifies risk loci for abdominal aortic aneurysm and highlights PCSK9 as a therapeutic target.

Abdominal aortic aneurysm (AAA) is a common disease with substantial heritability. In this study, we performed a genome-wide association meta-analysis from 14 discovery cohorts and uncovered 141 independent associations, including 97 previously unreported loci. A polygenic risk score derived from meta-analysis explained AAA risk beyond clinical risk factors. Genes at AAA risk loci indicate involvement of lipid metabolism, vascular development and remodeling, extracellular matrix dysregulation and inflammation as key mechanisms in AAA pathogenesis. These genes also indicate overlap between the development of AAA and other monogenic aortopathies, particularly via transforming growth factor ß signaling. Motivated by the strong evidence for the role of lipid metabolism in AAA, we used Mendelian randomization to establish the central role of nonhigh-density lipoprotein cholesterol in AAA and identified the opportunity for repurposing of proprotein convertase, subtilisin/kexin-type 9 (PCSK9) inhibitors. This was supported by a study demonstrating that PCSK9 loss of function prevented the development of AAA in a preclinical mouse model.

Endovascular treatment of a splenic vein aneurysm through a transhepatic approach.

Aneurysms of the portal vein and its branches have been rarely described. Their natural history is unknown although large ones (>3 cm in diameter) have been reported to cause rupture, thrombosis, duodenal or biliary obstruction, inferior vena cava compression and/or portal hypertension. We report the case of an incidentally diagnosed 4.5 cm splenic vein aneurysm repaired by endovascular treatment through a transhepatic route. The aneurysm was successfully excluded using a covered stent (Viabahn, Gore). The transhepatic route opens the possibility of offering a minimally invasive approach to vascular lesions of the portal vein system. Splenic vein aneurysms were first reported in 1953 (1) and they are part of the extrahepatic portal vein aneurysm group (2). Their mechanism of development is not well understood. Etiology may include congenital causes (inherent weakness of the vessel wall) or acquired causes (trauma, inflammation such as pancreatitis, liver disease, or portal hypertension). However, portal aneurysms do not seem to be the result of an isolated portal hypertension since they are extremely rare even in patients with this condition (3). The demographic characteristics of extrahepatic portal vein aneurysm include a female-to-male ratio of 2:1 and the median age of 52 years (range, 5-77 years). The size of the reported aneurysms ranges from 1.9 to 8 cm. The most common location of the aneurysm is in the main portal vein trunk, the junction of the superior mesenteric vein and the splenic vein, or at the hepatic hilus; intrahepatic venous aneurysms are rare (4, 5). Here, for the first time, we report the successful endovascular treatment of a splenic vein aneurysm through transhepatic percutaneous approach using a Viabahn stent.

Hypothenar hammer syndrome.

In 1934 von Rosen first described a posttraumatic thrombosis of the distal ulnar artery resulting from blunt a trauma to the hypothenar region. But it was Conn in 1970 who named it the "hypothenar hammer syndrome (HHS)" 1-2.