In what situation is defibrillation usually indicated?

Defibrillation is specifically indicated in the scenario of ventricular fibrillation. This is a critical condition where the heart's electrical activity becomes chaotic, preventing effective blood circulation. The purpose of defibrillation is to deliver an electric shock to the heart, which helps to reset the electrical system, allowing for a normal rhythm to be restored. Without defibrillation, ventricular fibrillation can quickly lead to cardiac arrest and death.

In contrast, situations like asystole, stable bradycardia, or a myocardial infarction do not typically benefit from defibrillation. Asystole indicates a lack of electrical activity in the heart and requires high-quality CPR and potential use of medications rather than shock. While stable bradycardia involves a slow heart rate where the heart is still functioning, it usually does not require defibrillation unless it progresses to a more severe situation. Myocardial infarction refers to a heart attack, which may require different medical interventions including medications and sometimes catheterization, but defibrillation is not the first line of treatment unless ventricular fibrillation develops.