Reference right atrial function determined by steady-state free precession cardiovascular magnetic resonance

Area of Science:

• Cardiology
• Medical Imaging
• Cardiac Function Assessment

Background:

• Atrial volumes and ejection fraction (EF) are superior to diameters for assessing atrial size and prognosis.
• Establishing reference values for right atrial volumes and EF using cardiovascular magnetic resonance (CMR) is crucial for identifying impaired right atrial function.

Purpose of the Study:

• To establish reference values for right atrial volumes and EF using CMR.
• To compare the reproducibility and speed of the standard short-axis (SA) method and the area-length (AL) method for assessing right atrial function.

Main Methods:

• Seventy healthy subjects underwent cardiovascular magnetic resonance (CMR) using steady-state free precession gradient-echo cine imaging.
• Right atrial function was assessed using both the standard short-axis (SA) method and the area-length (AL) method.
• Intraobserver, interobserver, and interstudy variability were evaluated for both methods.

Main Results:

• Maximal volumes, minimal volumes, and EF were higher with the AL method compared to the SA method.
• Atrial function measurements were not significantly related to gender or age.
• The SA method demonstrated lower intraobserver, interobserver, and interstudy variability compared to the AL method, indicating better reproducibility.
• Analysis time was significantly faster using the AL method (62±18 s) compared to the SA method (7±2 min).

Conclusions:

• Normal ranges for right atrial function differ significantly between the SA and AL methods.
• While the AL method is faster, the SA method offers superior reproducibility for assessing right atrial volumes and EF.
• Appropriate reference ranges specific to each method are necessary to accurately differentiate normal from abnormal right atrial function.