Colchicine therapy improves in vivo RV function in MCT rats. On echocardiography, TAPSE (PBS 2.9±0.01 mm, n=16, MCT 1.9±0.08 mm, n=21, MCT‐colchicine 2.4±0.10 mm, n=22) (A), percentage change in RVFW thickness (PBS 94±9%, n=16, MCT 24±3%, n=21, MCT‐colchicine 54±6%, n=22) (B), and estimated cardiac output (CO) (PBS 133±7 mL/min, n=16, MCT 67±3 mL/min, n=21, MCT‐colchicine 93±6 mL/min, n=22) (C) are all improved with colchicine treatment in MCT rats. Right heart catheterization‐derived thermodilution CO (PBS 130±8 mL/min, n=5, MCT 42±5 mL/min, n=10, MCT‐colchicine 67±8 mL/min, n=13) (D) and cardiac index (PBS 0.27±0.02 mL/[min·g], n=5, MCT 0.11±0.10 mL/[min·g], n=10, MCT‐colchicine 0.19±0.02 mL/[min·g], n=13) (E) are increased with colchicine treatment in MCT rats. *Significantly different from PBS, #significantly different from MCT rats as determined by 1‐way ANOVA with Tukey post hoc analysis. Colch indicates colchicine; MCT, monocrotaline; PBS, phosphate‐buffered saline; RVFW, right ventricle free wall; TAPSE, tricuspid annular plane systolic excursion.