INCIDENT AORTIC ROOT DILATATION IN THE GENERAL POPULATION: FINDINGS FROM THE PAMELA STUDY

Objective: We sought to assess the long-term changes in aortic root (AR) diameter in a population-based sample, focusing on new onset AR dilatation, as well as on the demographic and clinical variables independently related to this dynamic process. Design and method: A total of 1,122 participants with measurable echocardiographic parameters at baseline and after a ten-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 712 healthy normotensive PAMELA participants. Results: Over the ten-year follow-up new AR dilatation occurred in 3.4% (AR/BSA),4.4% (AR/height) and 7.3% (absolute AR), respectively. No substantial relationship was observed between baseline office and ambulatory BP or their changes over time and incident AR/BSA and AR/height dilatation. Baseline AR diameter and left ventricular mass index (LVMI) emerged as important predictors of AR dilation, regardless of the diagnostic criteria used. This was also the case for the 10-year change in LVMI. The strength of association between non-hemodynamic variables and new onset AR dilatation was variable, depending on the definition of the aortic phenotype. Conclusions: The incidence of AR dilatation in a general middle-aged population is a relatively infrequent but not so rare event and scarcely influenced by both office and out-office BP. On the contrary, it is strongly related to LVMI (and its variations over time). From a clinical perspective, this underlines that LVH prevention and regression can reduce the risk of AR dilatation in the community.