Reference values of left and right atrial volumes and phasic function based on a large sample of healthy Chinese adults: A cardiovascular magnetic resonance study

Background: The left and right atrial (LA and RA) size and function are tightly linked to the morbidity and mortality of multiple cardiovascular diseases. We aimed to establish cardiovascular magnetic resonance (CMR) reference values for LA and RA volumes and phasic function based on a large sample of healthy Chinese adults.

Methods: 408 validated healthy Chinese adults (54% men; aged 21-70 years) were included. LA and RA maximum, minimum, and pre-atrial contraction volumes (Vmax, Vmin, and Vpac); total, passive, and booster emptying fractions (EF total, EF passive, and EF booster); and total, passive, and active emptying volumes (TEV, PEV, and AEV) were measured on cine CMR. Normal reference values were calculated and were stratified by sex and age decades.

Results: Men demonstrated greater LAVmax, LAVmin, LAVpac, LAPEV, RAVmax, RAVmin, RAVpac, RATEV, and RAAEV, while women had higher LAEF total, LAEF booster, RAEF total, RAEF passive, and RAEF booster (all p < 0.05). Age was positively correlated with LAVpac and RAVpac in both sexes but was positively correlated with LAVmax, LAVmin, RAVmax, and RAVmin only in women (all p < 0.05). For both sexes, aging was associated with decreased LAEF total, LAEF passive, RAEF total, and RAEF passive, but increased LAEF booster (all p < 0.05).

Conclusion: We systematically provide age- and sex-specific CMR reference values for LA and RA volumes and phasic function based on a large sample of healthy Chinese adults with a wide age range. Both age and sex are closely associated with biatrial volumes and function.