New-onset aortic dilatation in the population: a quarter-century follow-up

Background Aortic size tends to increase with aging but the extent of this dynamic process has not been evaluated in long-term longitudinal population-based studies. We investigated the incidence of new-onset aortic root (AR) dilatation and its principal correlates among middle-aged adults over a 25-year time period. Methods A total of 471 participants with measurable echocardiographic parameters at baseline and after a 25-year follow-up were included in the analysis. Sex-specific upper limits of normality for absolute AR diameter, AR diameter indexed to body surface area (BSA) and to height were derived from healthy normotensive PAMELA participants. Results New AR dilatation occurred in 7.4% (AR/BSA), 9.1% (AR/height) and 14.6% (absolute AR), respectively. According to the AR/height index, the risk of new dilation was similar in men and women. As for echocardiographic parameters, baseline AR diameter emerged as a key predictor of AR dilation, regardless of the diagnostic criteria and the 10-year change in LVMI was positively associated to new AR/height dilatation. No significant relationship was observed between baseline office and ambulatory systolic/diastolic blood pressure or their changes over time with incident AR dilatation. Baseline and the 25-year change in 24-h pulse pressure were negatively related to new AR dilatation. Conclusions The incidence of AR dilatation from mid to late adulthood occurs in a small but clinically relevant fraction of participants and is unaffected by both office and out-office BP. It is significant related to baseline AR diameter and to the 25-year change in LVMI. Our data suggest that echocardiography performed in middle-aged individuals of both sexes may identify those at increased risk of future AR dilatation; moreover, preventing LVH may reduce the risk of progressive AR enlargement.