Fetal Echo Z-Scores

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Fetal echocardiography is routinely performed to screen for right or left ventricular hypoplasia, mitral stenosis, aortic stenosis, and pulmonary stenosis or atresia. Use this calculator to generate z-scores for fetal cardiac dimensions- including the mitral valve, left ventricle, aortic valve, and ascending aorta. Based upon work from the Royal Brompton Hospital, UK.

Based on today's date and the given EGA:
The LMP is ...
The EDD is ...
Site Measured Mean Range Z-Score
Left Heart (cm)
Right Heart (cm)
Isthmus & Duct (mm)


Development of Z-scores for fetal cardiac dimensions from echocardiography. Schneider C, McCrindle BW, Carvalho JS, Hornberger LK, McCarthy KP, Daubeney PE. Ultrasound Obstet Gynecol. 2005 Nov;26(6):599-605. Z-scores of the fetal aortic isthmus and duct: an aid to assessing arch hypoplasia. Pasquini L, Mellander M, Seale A, Matsui H, Roughton M, Ho SY, Gardiner HM. Ultrasound Obstet Gynecol. 2007 Jun;29(6):628-33.

Previous Comments

On Saturday Sep 22 2007, Allan Fisher said:

This is so much better than looking up on a chart. Thanks for the service.

On Sunday Dec 16 2007, Bunny said:

Thanks a lot! It is convenient to use and very useful.

On Thursday Jan 03 2008, Ruben J Acherman, MD. said:

Superb, Thank you very much to make it available

On Thursday Feb 28 2008, Rejane Dillenburg said:

it would be good to have Z scores for interventricular septal thickness. this 25 weeker's IVS measured 2.9mm, qualitatively it looks hypertrophic. I would consider 4mm hypertrophic close to term. thanks for your wonderful work !!!! R Dillenburg, Ped cardiologist, Canada

On Friday Feb 29 2008, Dan said:

Rejane : Thanks for the kind words. Z-scores for fetal ventricular wall thickness' would indeed be good... The AJC article by Firpo et al. is probably the closest I have found to providing this information, but they do not explicitly say that their data could be used for z-score calculations. They published the regression equations for the means, and SEE's. The Standard Error of the Estimate does not have the same statistical definition as the Standard Deviation, and my limited understanding of statistics prevents me from using them interchangeably for the purpose of calculating z-scores.

On Sunday May 25 2008, Jim Huhta said:

Nice job. A huge contribution. Call on me if you need help. Jim

On Sunday May 25 2008, Dan said:

Thanks Dr. Huhta- I might just do that (call on you).

On Sunday May 25 2008, Jason Grabham said:

Thanks for all the effort you've put into making these available. Look forward to the day when everyone uses the data...

On Tuesday Jul 08 2008, angela romano md said:

Are there z-scores available for fetal aortic root dimensions at the level of the sinuses? Thanks

On Tuesday Jul 08 2008, Dan said:

Dr. Romano: I am unaware of any such reference...