Of the 6814 MESA participants, 5098 had cardiac MRIs; 5004 were interpretable for LV measures (Figure 1).
The MESA–Right Ventricle Study is an ancillary study that selected 4634 of these scans (without regard to age, sex, or race/ethnicity), of which 4204 were available and interpretable for RV morphology.
Right ventricular structure and function are challenging to measure with standard transthoracic echocardiography, and existing studies have shown mixed results for RV determinants.
These single-center studies have not used epidemiological sampling strategies, instead focusing mostly on young adults of homogeneous race and ethnicity.
Attempts to derive normative values for RV measures have additionally been limited by a ratiometric rather than allometric approach to scaling, We hypothesized that RV mass, RV end-diastolic volume (RVEDV), RV end-systolic volume (RVESV), RV stroke volume (RVSV), and RV ejection fraction (RVEF) measured by cardiac magnetic resonance imaging (MRI) would differ by age, sex, and race/ethnicity in an older, multiethnic adult population without clinical cardiovascular disease.
We also derived sex-specific reference equations for RV mass, RV volumes, and RVEF in a healthy, nonobese, never-smoking subset and derived cutoffs to define abnormal RV morphology.
Older age was associated with lower RV mass (≈5% lower mass per decade), with larger age-related decrements in men than in women (≤0.02).
RVEDV and RVESV were calculated with the Simpson rule by summation of areas on each slice multiplied by the sum of slice thickness and image gap.All imaging was performed with 1.5-T magnets with a 4-element phased-array surface coil positioned anteriorly and posteriorly and ECG gating.Imaging consisted of fast gradient echo cine images with temporal resolution ≤50 milliseconds.The intrareader intraclass correlation coefficient from random, blinded rereads of 229 scans for RV mass was 0.94 and for RVEDV and RVEF from 230 scans was 0.99 and 0.89.The interreader intraclass correlation coefficients from random, blinded rereads of 240 scans for RV mass, RVEDV, and RVEF were 0.89, 0.96, and 0.80, respectively.