Long-term outcomes of abdominal aortic aneurysm screening in patients undergoing transthoracic echocardiography

Reports on the usefulness of abdominal aortic aneurysm (AAA) screening during transthoracic echocardiography (TTE) in Japan are limited. This study aimed to describe the prevalence of AAA among patients who underwent routine screening during TTE, as well as the long-term clinical outcomes of patients in whom AAA was detected.

We screened 46,353 consecutive patients who underwent TTE for suspected cardiac disease at our institution. Among these, a total of 1133 patients were identified as having AAA, defined as an abdominal aorta diameter of 30 mm or greater. After excluding patients with prior aortic surgery, including endovascular repair (n = 104), those with known AAA (n = 569), and those with known aortic dissection (n = 25), the study population consisted of 435 patients, all diagnosed with AAA for the first time.

The overall prevalence of AAA among patients undergoing TTE was 0.94%. The mean age was 76.8 years, and the study population was predominantly males (81.6%). The prevalence of AAA in patients under 60 years of age was low: 0.24% for men and 0.076% for women. The left atrial volume index was 43.8 ± 23.1 ml/m², the left ventricular mass was 164.9 ± 52.0 g, and the diameter of the sinus of Valsalva was 32.6 ± 4.4 mm, all of which were numerically higher than the normal values observed in a healthy Japanese population. During the median follow-up period of 2.0 years, 43 surgical or endovascular repairs of AAA, six aorta-related deaths, and 90 all-cause deaths occurred. The cumulative incidence of surgical or endovascular repair of AAA was 5.3% at 1 year, 11.5% at 3 years, and 18.1% at 5 years. The cumulative incidence of aorta-related death was modest: 0.3% at 1 year, 0.8% at 3 years, and 1.6% at 5 years.

The prevalence of newly diagnosed AAA among patients who underwent routine screening during TTE for suspected cardiac disease was 0.94% in the Japanese population, with the majority being 60 years or older. Approximately 10% of patients diagnosed with AAA underwent surgical or endovascular repair during follow-up, suggesting that this approach may be effective in preventing deaths caused by AAA.