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Biomarkers

Interventricular septum (IVS)

The muscular wall between the right and left ventricles of the heart

Echocardiography: the interventricular septum between the heart's ventricles

The interventricular septum (IVS) is the muscular wall between the right and left ventricles of the heart. Its thickness is measured on echocardiography at the end of diastole.

Thickening of the IVS is one of the main signs of left ventricular hypertrophy, and together with the relative wall thickness it helps determine the type of cardiac remodeling.

Reference ranges

The IVS thickness is measured at end-diastole, in millimeters:

Normal, women6 – 9 mm
Normal, men6 – 10 mm
Mild hypertrophy10–12 (women) / 11–13 (men)
Marked hypertrophy≥ 16 (women) / ≥ 17 (men)
Important: Asymmetric IVS thickening ≥15 mm is characteristic of hypertrophic cardiomyopathy.

What an elevated level means

IVS thickening develops with prolonged pressure overload — hypertension, aortic stenosis — and also in hypertrophic cardiomyopathy. A thickened septum relaxes worse, which impairs diastolic function.

What a low level means

A thickness within the normal range is a sign of healthy myocardium. Thinning and lack of contraction of a septal segment can occur after a previous myocardial infarction (scar).

How the test is done

It is measured on transthoracic echocardiography in the parasternal long-axis view (M-mode or 2D) at end-diastole. The value is compared with the posterior wall thickness, the chamber size and the myocardial mass.

What affects the value

  • An incorrect level or angle of measurement overestimates the thickness.
  • Accidentally including trabeculae or chordae in the measurement.
  • Tachycardia makes it hard to capture end-diastole.

Calculate using this marker

Calculators where Interventricular septum (IVS) is used directly:

Heart Age (Echo) A neural network reads five echocardiogram parameters — accurate to within ±5 years Open Heart Age AI analysis of your ECG — the biological age of your cardiovascular system Open

Frequently asked questions

Is an IVS of 12 mm dangerous?

This is mild thickening above normal. Most often it is linked to elevated blood pressure; the myocardial mass and blood pressure should be assessed and cardiomyopathy ruled out.

What makes the septum thicken?

The main causes are years of hypertension and valve defects (pressure overload), as well as hereditary hypertrophic cardiomyopathy.

Related terms

Echocardiography A heart ultrasound — an ultrasound study of the heart's structure and function Left ventricular hypertrophy (LVH) Thickening of the wall of the heart's main chamber from pressure overload Myocardial hypertrophy Thickening of the heart walls in response to increased load Relative wall thickness (RWT) An index of left-ventricular geometry — a marker of age-related heart remodeling Diastolic function The heart's ability to relax and fill with blood between contractions End-diastolic volume (EDV) The volume of blood in the left ventricle at the end of diastole — before ejection Blood pressure (BP) The pressure of blood on the artery walls, given as two values: SBP/DBP

Sources

  1. Left ventricular hypertrophy — Wikipedia
  2. ASE/EACVI Recommendations for Cardiac Chamber Quantification (2015)
info
This content is educational and does not replace consultation with a physician. Reference ranges may vary depending on the laboratory and method — rely on the ranges stated on your own test report.
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