Echocardiographic reference ranges for normal left ventricular 2D strain: results from the EACVI NORRE study

TLDR

The study aimed to establish age‑ and gender‑specific normal ranges for left‑ventricular strain using 2‑dimensional echocardiography in a large healthy cohort. The authors analyzed 2DE data from 549 healthy volunteers across 22 sites using a vendor‑independent software package to ensure homogeneous strain measurements. The study reported normal LV strain ranges, found age‑related decreases in longitudinal strain and increases in circumferential and radial strain, noted gender differences, and observed inter‑vendor variability for circumferential and radial but not longitudinal strain.

Abstract

To obtain the normal ranges for 2D echocardiographic (2DE) measurements of left ventricular (LV) strain from a large group of healthy volunteers accounting for age and gender. A total of 549 (mean age: 45.6 ± 13.3 years) healthy subjects were enrolled at 22 collaborating institutions of the Normal Reference Ranges for Echocardiography (NORRE) study. 2DE data sets have been analysed with a vendor-independent software package allowing homogeneous measurements irrespective of the echocardiographic equipment used to acquire the data sets. The lowest expected values of LV strains and twist calculated as ± 1.96 standard deviations from the mean were −16.7% in men and −17.8% in women for longitudinal strain, −22.3% and −23.6% for circumferential strain, 20.6% and 21.5% for radial strain, and 2.2 degrees and 1.9 degrees for twist, respectively. In multivariable analysis, longitudinal strain decreased with age whereas the opposite occurred with circumferential and radial strain. Male gender was associated with lower strain for longitudinal, circumferential, and radial strain. Inter-vendor differences were observed for circumferential and radial strain despite the use of vendor-independent software. Importantly, no intervendor differences were noted in longitudinal strain. The NORRE study provides contemporary, applicable 2D echocardiographic reference ranges for LV longitudinal, radial, and circumferential strain. Our data highlight the importance of age- and gender-specific reference values for LV strain.