Impact of papillary muscles on ventricular function measurements in 3 T cardiac magnetic resonance

Abstract Background Prior studies revealed, that left and right ventricular (LV, RV) volume, mass and function differ significantly, depending on trabeculae papillary and papillary muscles (TPM) have been included or excluded in LV and RV calculations. Methods A cohort of 101 patients underwent CMR. It constituted of 26 patients without pathological findings in CMR (reference group), patients with ischemic cardiomyopathy (ICM), dilated cardiomyopathy (DCM) and patients with left ventricular hypertrophy (25 per group). Left and right ventricular parameters were determined using previously established methods: Method 1 inclusion and method 2 exclusion of TPM in cavity volume. Results Compared with inclusion of TPM, exclusion of TPM in the LV and RV cavity volume resulted in significantly lower end-diastolic and end-systolic volume (EDV, ESV) and myocardial mass, and larger stroke volume and ejection fraction (SV, EF) (p0.001). The fraction of the TPM on the LV and RV mass was highest in DCM (18.4 ± 3.8%,) and in ICM (17.8 ± 3.2%) compared to the reference group (15.2 ± 2.5%, both p Conclusion Global CMR LV parameters are significantly affected by whether TPM are considered as part of the LV blood pool or as part of LV mass. Therefore, a consistent method of LV cavity delineation may be crucial during longitudinal follow-up to avoid misinterpretation and erroneous clinical decision-making.