Comparison of Right Atrial Volumes Measurement with Single-Plane Area-Length and Stack-of-Short-Axis Methods: A 3.0 Tesla Cardiac Magnetic Resonance Imaging Study (RF_FR_299)

Friday, January 31, 2025

9:50 AM – 10:00 AM East Coast USA Time

Location: Blue Room PreFunction

Presenting Author(s)

NN

Nabhat Noparatkailas, MD

Attending Physician
Faculty of Medicine, Chiang Mai University, Thailand

Primary Author(s)

NN

Nabhat Noparatkailas, MD

Attending Physician
Faculty of Medicine, Chiang Mai University, Thailand

Co-Author(s)

AS

Ankavipar Saprungruang, MD

Attending physician
Chulalongkorn University, Cardiac Center, King Chulalongkorn Memorial Hospital, Thailand
PS

Piyanun Sanguanwong, MD

Attending physician
Ananda Mahidol Hospital, Thailand
YV

Yongkasem Vorasettakarnkij, Co-first author

Chulalongkorn University and King Chulalongkorn Memorial Hospital, Thailand
MT

Monravee Tumkosit, MD

Assistant Professor
Chulalongkorn University and King Chulalongkorn Memorial Hospital, Thailand
PC

Pairoj Chattranukulchai, MD, MSc

Attending physician
Cardiac Center, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Bangkok, Thailand
NT

Nonthinkorn Theerasuwipakorn, MD, MSc

Attending physician
Chulalongkorn University, King Chulalongkorn Memorial Hospital, Thailand

Background: The measurement of right atrial (RA) volume is a critical process for evaluating cardiac size and function. The summation of short-axis volumes (SSAX) and the single-plane area-length (SPAL) methods are widely used techniques for RA volume quantification in cardiovascular magnetic resonance imaging (CMR). However, data on the reliability and agreement of these methods are limited and contentious. This study aims to evaluate the reliability of the SPAL and SSAX methods for RA volume measurement and to investigate the agreement between these two techniques.

Methods: CMR data from 40 healthy volunteers were reviewed to quantify RA volumes using the SSAX and SPAL (4-chamber view) methods. Comparison and agreement between these measurement techniques were assessed using paired t-tests and Bland-Altman plots, respectively. Intra- and inter-observer variations were evaluated using the intraclass correlation coefficient (ICC). The reproducibility of RA volume measurements, with and without the inclusion of RA appendage (RAA) volume, was also assessed.

Results: Among the 40 healthy participants, the mean age was 33.6 ± 6.1 years, with 50% being male. Females exhibited smaller RA volumes irrespective of the measurement method used. RA volumes measured using the SSAX method were significantly larger than those measured by the SPAL method. Bland-Altman plots demonstrated good agreement between the two methods. RA ejection fraction (RAEF) was the only parameter showing no statistical difference between the methods. Both the SSAX and SPAL methods demonstrated excellent reproducibility, with ICC values for intra- and inter-observer variations exceeding 0.80 when RAA volume was included. The exclusion of RAA volume from RA volume measurements resulted in lower reproducibility (ICC < 0.80).

Conclusion: The SPAL method underestimated RA volumes compared to the SSAX method. Despite this, the agreement between the two techniques was acceptable, supporting their interchangeable use. Importantly, RA volume measurements should reference the normal values specific to the measurement method employed. This study also suggests that RAA volume should be included in RA volume assessments, regardless of whether the SSAX or SPAL method is used.