Receiving a "no shock advised" message from the AED indicates what about the patient's rhythm?

Receiving a "no shock advised" message from the AED indicates that the patient's heart rhythm is not in a shockable state. Shockable rhythms typically include ventricular fibrillation and pulseless ventricular tachycardia; these are the rhythms where delivering a shock can potentially restore a normal heartbeat. When the AED analyzes the rhythm and determines there is no immediate need for an electric shock, it generally means the patient's heart is either in a normal rhythm or a non-shockable rhythm like asystole or pulseless electrical activity. This information is crucial for guiding further treatment and resuscitation efforts, as it informs responders of the nature of the cardiac condition and the appropriate interventions required.