What does this LOINC code represent?

This LOINC code identifies a lab observation, measurement, question, or clinical concept in a standardized format.

Is this enough to understand my test result?

No. The code identifies the test or observation, but the interpretation depends on the actual result, reference range, and clinical context.

LOINCActiveObservation

LOINC Code 112429-6: Heart rate variability SDNN [Time]

Name: LOINC Code 112429-6: Heart rate variability SDNN [Time]
Creator: HealthAssure Clinical Team
Published: 2026-05-21T11:17:22.499Z

112429-6 is a LOINC code used to identify Heart rate variability SDNN [Time] 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 Heart rate variability SDNN. It is commonly used with the system or sample type ^Patient.

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 Heart rate variability SDNN. It is commonly used with the system or sample type ^Patient.

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

What it does not mean

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

Key facts

Heart rate variability SDNN [Time]
Heart rate variability SDNN
This term represents the the standard deviation of the inter-beat (RR) intervals between normal heartbeats. The time between successive R-peaks after irregular beats or artifacts is removed.
CLIN; Heart beat; HR var SDNN; Point in time; Pulse; 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

Heart rate variability SDNN [Time]HR var SDNN TimeHeart rate variability SDNNCLINTimePt^Patient

Frequently asked questions

Code details

Code112429-6

SystemLOINC

Display nameHeart rate variability SDNN [Time]

DescriptionHeart rate variability SDNN

Short nameHR var SDNN Time

ComponentHeart rate variability SDNN

PropertyTime

TimingPt

System (specimen)^Patient

ScaleQn

ClassCLIN

Example unitsms

StatusACTIVE

Order/ObservationObservation

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.82

Last changed2.82

Consumer names

Heart rate variability SDNN

Part names

Heart rate variability SDNNTimePt^PatientQnTime (e.g. seconds)Point in time (spot)

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.