What is the minimum current that can disrupt heart rhythm?

The minimum current that can disrupt heart rhythm is approximately 75 mA. This level of electrical current can cause the heart to go into ventricular fibrillation, a condition where the heart quivers instead of pumping effectively, leading to a loss of effective circulation.

Understanding the significance of this threshold is important, particularly in contexts involving electrical safety and first aid. Currents lower than 75 mA may not necessarily cause immediate heart rhythm disruption, as lower levels often result in less severe effects or may not affect the cardiac rhythm at all.

The range of current values highlights the increasing risk associated with higher electrical currents. While lower levels, such as 25 mA and 50 mA, might cause muscle contractions or reflex responses, they are generally not sufficient to induce fibrillation. In contrast, currents of 100 mA and above pose even greater dangers, but for the context of your question regarding minimum currents, the threshold is understood to be around 75 mA.