The contractile properties of cardiomyocytes with different pacing frequencies. The contraction was stimulated with three pacing frequencies (2–6 Hz). (A–C) Diastolic SL (A), its changes (ΔSL; B), and the percent ratio of ΔSL/diastolic SL (DC) in LVCM (n = 30, n = 6) and RVCM (n = 30, n = 6) are summarized. (D–F) Time from peak to relaxation of ΔSL 10, 50, and 90% is represented as the time to relax₁₀, relax₅₀, and relax₉₀, respectively. All statistical tests performed using nested t test. *, P < 0.05; **, P < 0.01; ***, P < 0.001. The dot means the measured value of individual cells, and the black line in the column means average of measured value.