Quantification of atrial dynamics using cardiovascular magnetic resonance: inter-study reproducibility

Area of Science:

• Cardiology
• Medical Imaging
• Biomedical Engineering

Background:

• Cardiovascular magnetic resonance (CMR) quantifies atrial function using volumetric assessment and feature tracking (CMR-FT) for strain and strain rate (SR).
• Inter-study reproducibility is essential for longitudinal studies but not well-defined for CMR-derived left atrial (LA) and right atrial (RA) dynamics.

Purpose of the Study:

• To evaluate the inter-study reproducibility of CMR-based quantification of LA and RA reservoir, conduit, and booster pump functions.
• To assess potential diurnal variations in atrial function measurements.

Main Methods:

• 16 healthy volunteers underwent CMR imaging at three time points to assess inter-study reproducibility.
• LA and RA functions were quantified using volumetric indexes and CMR-FT-derived strain and SR.
• Comparisons were made between initial scans and repeat scans, as well as morning and afternoon scans.

Main Results:

• Inter-study reproducibility was acceptable for all volumetric, strain, and SR parameters of LA and RA.
• Reproducibility was better for volumetric indexes and strain than for SR, and better for LA than RA.
• Reservoir function showed the highest reproducibility (ICC 0.94-0.97 for LA, 0.76-0.96 for RA), followed by conduit and booster pump functions.
• No significant diurnal variation in atrial dynamics was observed.

Conclusions:

• CMR-based LA and RA function assessment, using volumetric, strain, or SR parameters, demonstrates acceptable inter-study reproducibility.
• LA function assessment is more reproducible than RA function assessment.
• Reservoir function is the most reproducible component, followed by conduit and booster pump functions, which is important for longitudinal research.