Table 3.

A comparison of the contractile properties of hECTs.

Ref	Force Measurement Conditions	Force-Frequency Relationship (FFR) & Frank-Starling Curve (FSC)	Contractile Force	Contractile Stress	Excitation Threshold (ET) & Maximum Capture Rate (MCR)	Spontaneous Beat Rate	Maximum Rate of Force Increase (+dF/dt) & Decrease (−dF/dt)	Time to Peak Force (TPF) & Time to 90% Relaxation (RT90)
Tulloch al et [1]	Force Transducer: spontaneous	Positive FSC	0.02 mN	~0.1 mN/m m2		60 bpm
Kensah et al [2]	Custom-Made Reactor: field stimulation (25V, 10ms)	Positive FSC	1.2–1.6 mN	4.4 mN/m m2		51–58 bpm		TPF = 47–59 ms RT90 = 63–69 ms
Mihic et al [3]	Optical Mapping: calcium-sensitive dye					63–78 Ca2+ transient cycles/min
Streckfuss-Bömeke et al [4]	Custom-Made Reactor: field stimulation (1.5Hz, 5ms, V = ET+10%)	Positive FSC	0.2 mN
Schaaf et al [5]	Post-Deflection: spontaneous		0.05–0.07 mN	~0.1 mN/m m2		40–70 bpm	+dF/dt = 10 mN/s −dF/dt = 6 mN/s	TPF = 200 ms RT90 = 300 ms
Turnbull et al [6]	Post-Deflection: field stimulation (2Hz, 5ms) Physiological Muscle Bath: field stimulation	Negative FFR Positive FSC	0.6 mN	0.5–0.6 mN/m m2 (muscle bath, 1Hz) 0.03–0.2 mN/m m2 (post-deflection, 1Hz)	ET = 0.4–2.2 V/cm (post-deflection) MCR = 3Hz (post-deflection)	42–100 bpm (post-deflection)	+dF/dt = 7–8 mN/mm2/s −dF/dt = 4–6 mN/mm2/s (post-deflection)	TPF = 80–96 ms RT90 = 106–127 ms (post-deflectio n)
Thavandiran et al [7]	Post-Deflection: field stimulation (2ms, 1–2Hz or 12V)				ET = 1.8–2.4 V/cm MCR = 6.1–6.5 Hz	30–60 bpm
Nunes et al [8]	Optical Mapping: voltage-sensitive dye				ET ≈ 0.8–2.3 V/cm (field stimulation) MCR = 2.8–4.8 Hz (point simulation) MCR = 5.2 Hz (field stimulation)
Hirt et al [9]	Post-Deflection: spontaneous		0.08 mN	~2.2 mN/m m2		74–90 bpm
Zhang et al [10]	Custom-Made Reactor: field stimulation (1Hz)	Positive FSC	1.9–4.1 mN	7.3–16.3 mN/m m2	MCR = 2.4–2.8 Hz (optical mapping, point stimulation)
Lu et al [11]	Force Transducer: field stimulation (1Hz, 5ms, V = ET+20%)	Negative FFR	0.2 mN			40–50 bpm

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