The relationship between RV capillary length (A), surface area (B), or lumen volume (C) and RV cardiac myocyte volume is shown by linear regression; the slope of each line (a = allometry coefficient) represent an estimate of the relative growth, with a slope of 1.0 demonstrating isometry. When compared against one another, the allometry coefficients were not significantly different (P = 0.34), suggesting similar rates of relative growth among all microvascular parameters (when compared with CM volume).