Dilatation of the ascending aorta – Growth rate, risk factors and clinical outcomes in the long-term follow-up

OBJECTIVES: To explore the risk factors, growth rate and outcomes of ascending aortic (AA) dilatation in patients scheduled for imaging follow-up. METHODS: This retrospective study included 143 patients who were followed-up with thoracic aortic CT-angiography. AA diameters were measured from aortic root (sinus Valsalva) and mid-AA at the baseline and after long-term follow-up. Risk factors and clinical outcomes were collected from medical records. The standard error of measurement (SEM) method was used to assess the statistical significance of the growth rate of AA dilatation. RESULTS: The patients' mean age was 64.0 ± 10.0 years (males n = 115, 80.4%). The mean imaging follow-up time was 3.4 ± 1.6 years and 5.7 ± 1.7 years in the clinical follow-up. According to the SEM method, 37.8% of the patients (n = 54) experienced significant AA growth; 18.9% (n = 27) in the aortic root (0.5 ± 0.7 mm/year), and 24.5% (n = 35) in the mid-AA (0.4 ± 0.5 mm/year). None of the patients experienced aortic rupture or dissection or died due to aortic reasons during the follow-up. Eighteen patients (12.6%) underwent elective surgical AA reconstruction and 10 patients (7.0%) died due to some other reason. Male gender was the only factor to associate with significant accelerated growth (p = 0.047). However, antihypertensive medication did seem to be a protective factor (p = 0.01). CONCLUSIONS: Less than half of the patients followed due to AA dilatation displayed significant AA growth during the long-term follow-up. In addition, the growth rate per year was small. None of the patients experienced any aortic catastrophes indicating that the prognosis of patients participating in regular imaging follow-up is good.