LOINCActiveObservation

LOINC Code 18524-9: P-R Interval Lead II

18524-9 is a LOINC code used to identify P-R Interval Lead II in laboratory and clinical observation data. You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges. LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component PR interval. It is commonly used with the system or sample type Lead II.

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component PR interval. It is commonly used with the system or sample type Lead II.

When is it used?

  • Used in lab systems, EHRs, and clinical data exchange.
  • May identify a test, observation, survey item, or clinical document request rather than a diagnosis.
  • Status: ACTIVE
  • Order vs observation: Observation
  • Method: EKG

What it does not mean

  • The code identifies the observation or test, not the actual result.

Key facts

  • P-R Interval Lead II
  • PR interval
  • Added to accommodate measures defined in CEN/TC251/PT007, SCP-ECG (Standard Communications Protocol for Computerized Electrocardiography)
  • 2; Cardio; Cardiology; ECG; EKG.MEASUREMENTS; Electrocardiogram; Electrocardiograph; Heart Disease; L-II; Point in time; P-R interval; QNT; Quan; Quant; Quantitative; Random

Where you may see this code

You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges.

Common synonyms

P-R Interval Lead IIP-R interval L-IIPR intervalEKG.MEASTimePtLead II

Frequently asked questions

Code details

Code18524-9
SystemLOINC
Display nameP-R Interval Lead II
DescriptionPR interval
Short nameP-R interval L-II
ComponentPR interval
PropertyTime
TimingPt
System (specimen)Lead II
ScaleQn
MethodEKG
ClassEKG.MEAS
Example unitss
StatusACTIVE
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released1.0l
Last changed2.48

Part names

PR intervalTimePtLead IIQnEKGP-R IntervalTime (e.g. seconds)Point in time (spot)Electrocardiogram (EKG)

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from LOINC. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.

LOINC Code 18524-9 | HealthAssure