Sex differences and higher upper normal limits for left atrial end-systolic volume in individuals in their mid-60s: data from the ACE 1950 Study

AIMS: The current study aimed to describe normal values of left atrial (LA) volumes and LA emptying fraction (LAEF) in a large sample in their mid-60s from the general population and to explore sex differences. METHODS AND RESULTS: In the Akershus Cardiac Examination (ACE) 1950 Study, body surface area-indexed LA maximum (LAVimax) and minimum (LAVimin) volumes and LAEF were measured in 3489 individuals aged 63.9 ± 0.6 years from the general population. A healthy group of 832 individuals was defined. Data are presented as mean ± standard deviation (SD) and a normal range of mean ± 2 SD. T-tests were used for comparisons. In the healthy group, mean LAVimax was 25.5 ± 6.2 mL/m2 and the normal range was 13.1-37.9 mL/m2. Men had significantly larger body surface area-indexed volumes than women, but there was no difference in LAEF. The mean LAVimax for healthy men was 26.4 ± 6.5 mL/m2, for healthy women 24.9 ± 5.8 mL/m2 (P < 0.001) and the upper normal limits were 39.4 and 36.5 mL/m2, respectively. In the healthy group, 13.0% of all men and 5.4% of all women had LAVimax above the current upper normal limit of 34 mL/m2. CONCLUSION: A large proportion of healthy individuals, in particular men, had LAVimax >34 mL/m2. Our findings suggest that the recommended cut-off may be too low at the age of 65 years and above and that sex-specific cut-offs should be considered.