Evidence implicating Helicobacter pylori (H. pylori) in coronary artery disease and aneurysmal lesions is controversial. No published data have related H. pylori infection to ascending aortic aneurysms and penetrating ulcers, although both of these lesions may have an infectious components in their initiating process. We sought to investigate possible H. pylori infection in 54 human specimens of 42 aortic aneurysms and 12 penetrating ulcers. No evidence of H. pylori was found in these specimens.