<div>Mechanical stretch may play a role in initiating arrhythmia in heart via the activation of stretch-activated channels (SACs). To investigate the role of mechanical stretch, SAC blockers were used previously. Gadolinium (Gd3+) was a potential SAC blocker. However, in previous studies the effect of Gd3+ was not consistent. Thus, we tested the effect of Gd3+ on inhibiting cardiac mechano-sensitivity in a isolated pig heart model. The results show that Gd3+ cannot inhibit cardiac mechano-sensitivity in isolated pig hearts and thus using it to probe the role of mechanical stimulation in whole heart preparations should be done with great caution.<br></div>