functional refractory period
Also written as: FRP — Functional Refractory Period
The shortest interval between two consecutively conducted impulses through a specific cardiac structure.
Full Definition
The functional refractory period (FRP) is the shortest interval between two consecutively conducted impulses that can traverse a specific cardiac structure or pathway. Unlike the effective refractory period, which measures the longest coupling interval that fails to conduct, FRP represents the minimum time between successfully conducted beats. This parameter reflects both the intrinsic recovery properties of the tissue and any conduction delay that occurs at short coupling intervals. FRP is always equal to or longer than the effective refractory period and is particularly important in assessing AV node function and accessory pathway properties during rapid atrial stimulation.
Usage
Usage note: Commonly abbreviated as FRP; always equal to or longer than effective refractory period.
In Context
- "The AV nodal functional refractory period was 400 milliseconds, limiting the maximum ventricular rate during atrial fibrillation." — Electrophysiology study results
- "The accessory pathway's short functional refractory period of 250 milliseconds posed a risk for rapid conduction during atrial fibrillation." — Risk assessment report