Comprehensive reference ranges for cardiovascular magnetic resonance: time to move on from single centre data?

Area of Science:

• Cardiology
• Medical Imaging
• Biomedical Engineering

Background:

• Cardiovascular magnetic resonance (CMR) is crucial for assessing cardiovascular structure, function, and tissue characteristics.
• Accurate, clearly defined normal ranges are fundamental for interpreting CMR measurements.
• Variations in CMR acquisition and analysis can impact measurement accuracy and reproducibility.

Purpose of the Study:

• To determine age- and sex-specific normal ranges for a wide array of CMR measurements in healthy adults.
• To assess the inter-scan reproducibility of these CMR measurements.
• To evaluate the influence of common variations in CMR practice on measurement outcomes.

Main Methods:

• 122 healthy adults underwent CMR (3T, Siemens), with 20 participants having repeat scans for reproducibility assessment.
• Image analysis was performed using cvi42 by experienced observers.
• Age- and sex-specific reference ranges were generated for parameters including ventricular volumes, mass, strains, atrial dimensions, and tissue characteristics (T1, T2, T2*).

Main Results:

• Comprehensive age- and sex-specific reference ranges and inter-scan reproducibility data are provided for numerous CMR parameters.
• Myocardial T1 measurement demonstrated the highest reproducibility among all assessed CMR parameters.
• Common variations in practice, such as slice selection and measurement planes, led to significant differences in results (e.g., indexed left atrial volume).

Conclusions:

• This study provides a valuable set of reference ranges and reproducibility data for common CMR measurements.
• Clinical practice variations can introduce significant variability, impacting the definition and application of normal ranges.
• Larger, multi-ethnic cohorts are recommended for establishing more robust and universally applicable CMR reference ranges.