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LOINC Code 77921-5: Left ventricular Myocardial mass/Height exp 2.7 [Mass/Area] by US.M-mode+Calculated by cube method

77921-5 is a LOINC code used to identify Left ventricular Myocardial mass/Height exp 2.7 [Mass/Area] by US.M-mode+Calculated by cube method 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 Myocardial mass/Height exp 2.7. It is commonly used with the system or sample type Heart.ventricle.left.

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 Myocardial mass/Height exp 2.7. It is commonly used with the system or sample type Heart.ventricle.left.

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.M-mode+Calculated by cube method

What it does not mean

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

Key facts

Left ventricular Myocardial mass/Height exp 2.7 [Mass/Area] by US.M-mode+Calculated by cube method
Myocardial mass/Height exp 2.7
The myocardial index is the left ventricular (LV) mass normalized for body size, which can be approximated by different measures including body surface area (BSA) and height. This term represents an index based on height^2.7. The cube function is a method for calculating left ventricular mass from M-mode echocardiography measurements and assumes a long- to short-axis length ratio of 21. The formula is as follows: LV mass = 1.04(IVSd + LVIDd + PWTd)^3 - LVID^3), where IVSd = interventricular septal thickness, LVIDd = left ventricular internal diameter (short axis), and PWTd = posterior wall thickness, all measured during end-diastole. [PMID: 2936235]
Calc; Calculation; CARD.US; Cardiac; Cardio; Cardiology; Echography; Heart Disease; Hrt; Hrt ventr; L; LT; LV; MAric; MM; mmode; Myo mass; Point in time; QNT; Quan; Quant; Quantitative; Random; Sonogram; Sonograph; Sonography; ULS; Ultrasound; US.M-mode+cube; Ventricular

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

Left ventricular Myocardial mass/Height exp 2.7 [Mass/Area] by US.M-mode+Calculated by cube methodLV Myo/Ht exp 2.7 US.M-mode+cubeMyocardial mass/Height exp 2.7CARD.USArMassPtHeart.ventricle.left

Frequently asked questions

Code details

Code77921-5
SystemLOINC
Display nameLeft ventricular Myocardial mass/Height exp 2.7 [Mass/Area] by US.M-mode+Calculated by cube method
DescriptionMyocardial mass/Height exp 2.7
Short nameLV Myo/Ht exp 2.7 US.M-mode+cube
ComponentMyocardial mass/Height exp 2.7
PropertyArMass
TimingPt
System (specimen)Heart.ventricle.left
ScaleQn
MethodUS.M-mode+Calculated by cube method
ClassCARD.US
Example unitsg/m2.7
StatusACTIVE
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.52
Last changed2.56

Part names

Myocardial mass/Height exp 2.7ArMassPtHeart.ventricle.leftQnUS.M-mode+Calculated by cube methodMass/AreaPoint in time (spot)Heart ventricle - left

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 77921-5 | HealthAssure