The QT interval on an electrocardiogram represents part of the timing of ventricular electrical activity. QT prolongation is important because, in some circumstances, it can be associated with a greater possibility of potentially dangerous ventricular arrhythmias. The basic physiology is outlined in the NCBI overview of long QT syndrome, though that clinical topic should not be treated as a direct prediction tool for any one exposure.
Ibogaine has drawn particular attention because laboratory work and clinical observations have raised concern about effects on cardiac repolarization. This concern sits alongside the broader pharmacology described in the pharmacology overview: ibogaine is not defined by one receptor or one pathway, and its effects may unfold across several targets and over time.
Repolarization
The QT interval is a surface measurement related to how ventricular cells reset electrically after each beat.
Context matters
Heart rate, electrolyte balance, co-exposures, illness, and measurement method can influence interpretation.
Ion channels
Drug-related changes in ionic currents can alter repolarization, sometimes without a simple dose-to-risk relationship.
Not a guarantee
A pharmacologic signal does not specify what will happen in a particular person or setting.