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 18104-0: Aortic valve Pressure half time by US.doppler

Name: LOINC Code 18104-0: Aortic valve Pressure half time by US.doppler
Creator: HealthAssure Clinical Team
Published: 2026-05-21T11:17:27.585Z

18104-0 is a LOINC code used to identify Aortic valve Pressure half time by US.doppler 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 Pressure half time. It is commonly used with the system or sample type Aortic valve.

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 Pressure half time. It is commonly used with the system or sample type Aortic valve.

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: US.doppler

What it does not mean

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

Key facts

Aortic valve Pressure half time by US.doppler
Pressure half time
time from peak AV gradient to 1/2 peak gradient
AO; AoV; AV; CARD.US; Cardio; Cardiology; DOP; DUPLEX; Echography; Heart Disease; P1/2T; PHT; Point in time; QNT; Quan; Quant; Quantitative; Random; Sonogram; Sonograph; Sonography; T1/2; ULS; Ultrasound

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

Aortic valve Pressure half time by US.dopplerAV PHT DOPPressure half timeCARD.USTimePtAortic valve

Frequently asked questions

Code details

Code18104-0

SystemLOINC

Display nameAortic valve Pressure half time by US.doppler

DescriptionPressure half time

Short nameAV PHT DOP

ComponentPressure half time

PropertyTime

TimingPt

System (specimen)Aortic valve

ScaleQn

MethodUS.doppler

ClassCARD.US

Example unitsms

StatusACTIVE

Order/ObservationObservation

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released1.0l

Last changed2.54

Part names

Pressure half timeTimePtAortic valveQnUS.dopplerTime (e.g. seconds)Point in time (spot)Ultrasound.doppler

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.