Choose your data source:
Boston (2007)
Washington, D.C. (2008)
Montreal, Canada (2010)
I also have a handy little comparison and charting tool:
CNMC Coronary Artery Z-Scores
Z-Scores of the left main coronary artery (LMCA), left anterior descending (LAD), and right coronary artery (RCA) using an allometric equation derived from 432 normal patients, aged 0 – 20 years.
References:
Coronary Artery Z Score Regression Equations and Calculators Derived From a Large Heterogeneous Population of Children Undergoing Echocardiography. Olivieri L, Arling B, Friberg M, Sable C. Journal of the American Society of Echocardiography - 12 December 2008.
Ascending Aorta Z-Scores
Calculate Z-Scores of the ascending aorta and aortic root using data published in 2006 from Halifax, Nova Scotia. Per the authors: "Measurements were made in systole... in the parasternal long axis... from inner edge to inner edge. The ascending aorta was measured at the level of the right pulmonary artery."
Also see: consolidated aortic root z-score calculator
| Location | Measured | Mean | Range | Z-Score | Percentile |
|---|---|---|---|---|---|
References
Dilatation of the ascending aorta in paediatric patients with bicuspid aortic valve: frequency, rate of progression and risk factors. Warren AE, Boyd ML, O'Connell C, Dodds L. Heart. 2006 Oct;92(10):1496-500. Epub 2006 Mar 17. PMID: 16547208
Z-Scores of Cardiac Structures | Wessex Data
These are the default z-score equations currently used on KinetDx/syngoDynamics workstations...
Z scores of 15 cardiac structures including the mitral valve, aortic valve, pulmonary arteries, etc. Regression equations were derived relating cardiac dimensions to the size of the body using a population of 125 normal infants and children. From the Wessex Cardiothoracic Unit, Southampton General Hospital, UK.
| Location | Measured | Mean | Range | Z-Score |
|---|---|---|---|---|
References
Relationship of the dimension of cardiac structures to body size: an echocardiographic study in normal infants and children.
Daubeney PE, Blackstone EH, Weintraub RG, Slavik Z, Scanlon J, Webber SA.
Cardiol Young. 1999 Jul;9(4):402-10.
About
THIS SITE HAS BEEN DEPRECATED
please visit the new site
About Z-Scores (in general)
According to the American Society of Echo's Guidelines and Standards for Performance of a Pediatric Echocardiogram:In addition to reporting the absolute values, it is useful to report quantitative measures within the context of age- or size-appropriate norms (eg, z-score values).
A z-score indicates:
how many standard deviations an observation is above or below the mean. It allows comparison of observations from different normal distributions, which is done frequently in research.(See the Wikipedia entry for more information about z-scores.)Concerning the application of z-scores to pediatric cardiology, interested persons should read:
- the invited editorial Establishing norms for echocardiographic measurements of cardiovascular structures and function in children
- the original article Theoretical and empirical derivation of cardiovascular allometric relationships in children
- the excellent chapter in Nadas' Pediatric Cardiology: Methodological Issues in Clinical Research
- the recent work, A Novel Method of Expressing Left Ventricular Mass Relative to Body Size in Children
- other recent works:
About Me
My name is Dan Dyar. Among many other things, I am a Pediatric Cardiac Sonographer. Having worked in this field since Before The Internet, I sometimes observe the collision of technology and information in this field and am astonished by the disparity: we are simultaneously incredibly advanced and desperately primitive.I hope this website helps soften these collision.
Should you wish to contact me, fill out the form here and hope for the best.
Disclaimer
The calculators provided are not meant to be a substitute for professional advice and are not to be used for medical diagnosis. All calculations must be confirmed before clinical use or diagnostic purposes by qualified medical professionals. The author makes no claims of the accuracy of the information contained herein. The authors make no claims whatsoever, expressed or implied, about the authenticity, accuracy, reliability, completeness or timeliness of the material, software, text, graphics and links given. In no event shall the author, suppliers, affiliates or any third parties be liable in any manner whatsoever for any damage arising upon use of any information provided.
THE INFORMATION, SOFTWARE, PRODUCTS, AND SERVICES INCLUDED IN OR AVAILABLE THROUGH THE WEB SITE MAY INCLUDE INACCURACIES OR TYPOGRAPHICAL ERRORS. CHANGES ARE PERIODICALLY ADDED TO THE INFORMATION HEREIN. CHANGES IN THE WEB SITE MAY BE MADE AT ANY TIME. ADVICE RECEIVED VIA THE WEB SITE SHOULD NOT BE RELIED UPON FOR PERSONAL, MEDICAL, LEGAL OR FINANCIAL DECISIONS AND YOU SHOULD CONSULT AN APPROPRIATE PROFESSIONAL FOR SPECIFIC ADVICE TAILORED TO YOUR SITUATION. IF YOU ARE DISSATISFIED WITH ANY PORTION OF THE WEB SITE, OR WITH ANY OF THESE TERMS OF USE, YOUR SOLE AND EXCLUSIVE REMEDY IS TO DISCONTINUE USING THE WEB SITE.
Pulmonary Valve Z-Score Table
Please see this site instead: http://www.parameterz.com/tools/valve-zscore-tables
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References
Two-dimensional echocardiographic valve measurements in healthy children: gender-specific differences. Zilberman MV, Khoury PR, Kimball RT. Pediatr Cardiol. 2005 Jul-Aug;26(4):356-60. Erratum in: Pediatr Cardiol. 2008 Mar;29(2):475.
Aortic Valve Z-Score Table
Please see this site instead: http://www.parameterz.com/tools/valve-zscore-tables
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References
Two-dimensional echocardiographic valve measurements in healthy children: gender-specific differences. Zilberman MV, Khoury PR, Kimball RT. Pediatr Cardiol. 2005 Jul-Aug;26(4):356-60. Erratum in: Pediatr Cardiol. 2008 Mar;29(2):475.
Tricuspid Valve Z-Score Table
Please see this site instead: http://www.parameterz.com/tools/valve-zscore-tables
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References
Two-dimensional echocardiographic valve measurements in healthy children: gender-specific differences. Zilberman MV, Khoury PR, Kimball RT. Pediatr Cardiol. 2005 Jul-Aug;26(4):356-60. Erratum in: Pediatr Cardiol. 2008 Mar;29(2):475.
Z-Scores of Cardiac Structures | Detroit Data
Calculate the z-scores of 21 common 2D and M-Mode echo measurements, related to body surface area. Measurement sites include the mitral valve, left ventricle, aortic valve, aortic arch, pulmonary valve, and pulmonary arteries. Data is from 782 patients evaluated at the Children's Hospital of Michigan.
References
Regression equations for calculation of z scores of cardiac structures in a large cohort of healthy infants, children, and adolescents: an echocardiographic study. Pettersen MD, Du W, Skeens ME, Humes RA. J Am Soc Echocardiogr. 2008 Aug;21(8):922-34.Comments
On Saturday Apr 19 2008, Dan said: version 0.1, April 19 2008
On Tuesday Apr 22 2008, Dan said: version 0.2 constrained the calculations to subjects with BSA < 2.0. See this post.
On Thursday May 01 2008, Rick Jensen said: Very easy and helpful; feels trustworthy. I thought there were ascending aortic values?
On Thursday May 01 2008, Dan said: Curiously, the AAO did not make it into this publication, but they did include aortic measurements like the "distal aortic arch" and "aorta at diaphragm" ... Go figure.
On Sunday May 25 2008, Yael said: Excellent job!! One thing though, It is easier to have the results as you enter the numbers kike un the coronary artery section and not to hit the calculate button. Yael
On Sunday May 25 2008, Lloyd Marks said: Although I can access your site on my Treo, I can't run the application. Any way to create an application that would allow you to do this on a Treo nor other PDA. One idea - Perhaps you could get Epocrates to add this to their medmath functions. Maybe they would even pay you for it.
On Sunday May 25 2008, Dan said: @ Yael: Good point- it is quite cumbersome at this point. I only recently figured out JavaScript and it's "onChange" event... Updating this calculator is now on my "to do" list. @Dr. Marks: You are way ahead of the curve there on your Treo. This site was developed primarily as a tool for our echo lab- as an extension to our report writing software. Considerations for mobile devices never entered the picture.
On Monday May 26 2008, John Plowden said: Great job Dan. Would be nice to have the option of entering the weight in pounds and oz and the length in inches and have the program convert it automatically. Just a thought, probably would not be too hard to do. Thanks again for all of your efforts
On Tuesday May 27 2008, Giacomo Pongiglione said: Well done. Thanks.
On Tuesday May 27 2008, Dan said: Thanks for the kind words. @ Dr. Plowden: We can't afford to lose another Mars Explorer. *grin* I thought the International System was the standard for reporting height and weight units of measure, no?
On Wednesday May 28 2008, Jorge Gomez said: Seams accurate. Very Helpful!!!
On Thursday May 29 2008, Richard W Gratian, M.D. said: We started using your calculator today. It is very convenient but unfortunately, the upper limit appears to be 2.0 m2 which we found out with our third patient. Is there a calculator for patients above 2.0 m2? Thanks. Rick Gratian
On Thursday May 29 2008, Dan said: Dr. Gratian: You raise an interesting point. Shortly after I built this calculator and starting using it myself, I noticed some unbelievable results on patients with BSA > 2.0 m2. I went back to the article and sought the descriptive characteristics of their patient population. These descriptive characteristics were missing from the article. (as of right now, this article is still an "In Press Corrected Proof" so I suppose the information could yet be added). The supplied figures for the article top out at 2.0 m2, so I chose to constrain the calculations at this limit. Thanks for your comments!
On Friday May 30 2008, Dan said: modified the calculator to update the z-scores as the data is entered
On Wednesday Jun 04 2008, bleb said: entering Z-values for ascending aora (after ST junction) would be helpful. e.g. Bic Ao valve, Turner S.
On Thursday Jun 05 2008, giacomo said: Did you ceck the equations and the coefficients provided in your paper? The result of your equation 2 is -0.384 (how can a negative value be the mean?) while it should be 0.68. On the other end, if you enter 0.68 as Mean y into equation 4 the resulting z value is not - 2.48
On Thursday Jun 05 2008, Dan said: Bleb: the authors did not include data for the AAO- I can't answer as to why... Dr. Pongiglione: the results of "equation 2" in the article refers to the natural log-transformed predicted value. To get the value (y) back in the original units, it needs to be back-transformed, i.e. e raised to the power y; the JavaScript equivalent is Math.exp(y) I hope this helps.
On Tuesday Jun 17 2008, kalyani trivedi said: fantastic; now I can be very precise with ease. Thank you very much for putting this together.
On Thursday Jun 19 2008, Volker Petersen said: This ist what I was looking for a long time, thank you
On Friday Jun 20 2008, satish adwani said: Excellent! Keep it up. Very helpful. I always keep it on when I do Echo's in my clinic!
On Wednesday Jul 23 2008, Marcos said:
On Friday Jul 25 2008, Peter said: Thank you very much. Not only I have waited such a long time for an easy way to get these data calculated for each of our patients.
On Thursday Jul 31 2008, MARIO CAZZANIGA said: do you have Z score calculations of magnetic resonance: RVEDV, RVESV, LVEDV, LVESV, RVEF, LVEF ?
On Thursday Jul 31 2008, Dan said: Mario: Sorry, my primary focus has been on reference values for pediatric echocardiography.
On Monday Aug 04 2008, Jan du Plessis said: This is an extremely useful site
On Thursday Aug 07 2008, ayse sarioglu said: This an extremely useful site.Thank you very much for your excelent work.
On Thursday Aug 14 2008, Dr Rezoana said: Would u please help us to find the Z score of above mentioned psarameters
On Sunday Aug 31 2008, Keyhan Sayadpour, MD said: At Children's Medical Center, Tehran, Iran, we routinely use this website. It is great and very helpful.
On Wednesday Sep 03 2008, shanthi sivanadam said: Would appreciate if you could add Z-score/percentile .
M-Mode Z-Scores
Please see this updated site: http://www.parameterz.com/sites/m-mode
References
Normal values of M mode echocardiographic measurements of more than 2000 healthy infants and children in central Europe. C Kampmann, C Wiethoff, A Wenzel, G Stolz, M Betancor, C Wippermann, R Huth, P Habermehl, M Knuf, T Emschermann, and H Stopfkuchen Heart. 2000 June; 83(6): 667–672.
LV Mass Z-Scores
...these could easily be included in echocardiography software, which would allow automated generation of an LV mass-for-height z score and percentile for each child undergoing echocardiography.LV mass was estimated by M-mode echocardiography in 440 healthy nonobese reference children (birth to 21 years) from Boston Children's Hospital.
References
A novel method of expressing left ventricular mass relative to body size in children. Foster BJ, Mackie AS, Mitsnefes M, Ali H, Mamber S, Colan SD. Circulation. 2008 May 27;117(21):2769-75.
Fetal Echo Z-Scores
This calculator is being deprecated. Try the new web app instead.
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) | ||||
References
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...
Coronary Artery Z-Scores
Primarily useful for patients with Kawasaki Disease, this calculator will return a z-score for the left main coronary artery (LMCA), left anterior descending (LAD), and right main coronary artery (RCA).
| BSA: | ||||
| Site | Measurement | Mean | Range | Z-Score |
|---|---|---|---|---|
References:
Coronary artery involvement in children with Kawasaki disease: risk factors from analysis of serial normalized measurements. McCrindle BW, Li JS, Minich LL, Colan SD, Atz AM, Takahashi M, Vetter VL, Gersony WM, Mitchell PD, Newburger JW; Pediatric Heart Network Investigators. Circulation. 2007 Jul 10;116(2):174-9.
Pevious Comments
On Wednesday Sep 12 2007, Master said:
Well done grasshopper. Listen for the sound of one hand clapping.
On Friday Dec 21 2007, Dr P K Tiwary said:
Excellent job!! Many thanks. Keep it up.
On Monday Jan 28 2008, Dr Aniruddha De said:
Can Z score be calculated offline? Please let me know how?
On Monday Jan 28 2008, Dan said:
>>Can the equations be calculated offline? Sure! >>how? From the McCrindle article in Circulation: "The predicted value for a patient of a given body surface area can be obtained by solving the first exponential regression equation, and the associated SD of that predicted value can be obtained by solving the second linear regression equation. The z score is obtained by dividing the difference between the actual measurement and the predicted measurement by the SD" -- the equations are printed in the journal
On Wednesday Apr 09 2008, REJANE DILLENBURG said:
it would be helpful to have the option of using only BSA, some kids don't get their height measured every time, and estimated BSA can be calculated by weight only
On Thursday Apr 10 2008, Dan said:
REJANE: the calculator works that way already- if height is not entered the BSA will be estimated from weight alone using this formula: 0.1 * (WT 0.67) Cheers!
On Tuesday Apr 22 2008, Al said:
very helpful, thanks!
On Tuesday Apr 22 2008, John said:
why not circumflex?
On Tuesday Apr 22 2008, Dan said:
@Al: you're welcome! @John: I obviously can't speak for the authors of these articles, but based on my own experience I could venture a guess: the circumflex coronary artery is difficult to image (by echo) with any reliability.
On Saturday May 24 2008, Neill Videlefsky said:
Thank you so much for this valuable information.
On Sunday May 25 2008, bleb said:
By adding or removing Weight, the Z-score jumps within a wide range. It is iportant to see the origine of the calculated Z-score once calculated (i.e., reference ACTUALLY used next to the calculated Z-score). Fianlly, I have tried to use the Z-score from McCrindle, I found it very complex (not user friendly at all) and very likely imbedded with errors (compared to 3 formulae calculations, including one derived from our databse). What do you think of McCrindles equation? Erroneous or adequate?
On Sunday May 25 2008, Dan said:
@Neill: You are quite welcome. @bleb: The WEIGHT is a required component of the BSA calculation- removing it forces the BSA == zero and, you are quite right, causes the z-scores to become quite unbelievable. I probably should have made the calculator handle this situation differently- in the meantime, ALWAYS include a weight. Regarding the complexity and possible errors of the McCrindle equations: I have encountered no such problems. Can you provide a specific example of how the calculations performed might be erroneous? I have tried hard to simply facilitate the calculation of z-scores from published literature without injecting my personal bias about the utility or suitability of the calculations for their purpose. However, since you asked: I find the McCrindle equations to be more than adequate: I think they are excellent- indeed, their published equations are the very model for how to calculate a z-score correctly.
On Monday May 26 2008, bleb said:
indeed no error in McCrindles CA equations, but a pitfall... that is, measured CA should be entered in CENTIMETERS (quite bizarre for such a cute little vessel)!, or else (I adjusted the formula to read my mm-CA in my XLS spreadsheet, but after a rest I HAD to take).
On Monday May 26 2008, Dan said:
I'm glad you got it figured out!
On Wednesday Jun 11 2008, R BADER said:
excellent effort ,need to post your resources if possible (references)
On Wednesday Jun 11 2008, Dan said:
R: "this calculator will return a z-score for the left main coronary artery (LMCA), left anterior descending (LAD), and right main coronary artery (RCA) as described by de Zorzi et al. (1998). The body surface area is calculated as described by Haycock et al. (1978). UPDATE (21 July 2007): The regression equations of McCrindle et al. (2007) have been added." What other resources/references do you need?
On Thursday Jun 19 2008, Samira Saady Morhy said:
Congratulations for this wonderful and helpful site!! The range for coronary arteries diameters in the de Zorzi et al. study (that is use in this site) are greater than those found in the study done by Tan et al. (Pediatric Cardiology 24:238-335,2003). In this study 390 health children were evaluated by echo. Why do you prefer the diameters described by de Zorzi and coworkers? Don’t you think that Tan and colleagues studied a greater number of children in echo machines with a better resolution? Warmst regards, Samira S Morhy, MD, PhD, FASE Hospital Israelita Albert Einstein Echocardiography Laboratory Sao Paulo, Brazil
On Thursday Jun 19 2008, Dan said:
The default coronary artery z-score reference is the McCrindle/Circulation 2007 article, actually. I prefer THAT reference over the Tan/Pediatric Cardiology 2003 reference because 1) it is more recent and, 2) it is more sophisticated in the manner in which the standard deviation is dealt with: The 2007 Circulation equations allow for nonconstant variance, whereas the 2003 Ped. Card. equations do NOT. I do like how they made up a new word for the Pediatric Cardiology article's title though: "Coronary normograms and the coronary-aorta index: objective determinants of coronary artery dilatation."
On Thursday Jun 19 2008, Ramesh Parmar said:
The Z scores were never these handy before. The site is very easy to use and information it gives is very reliable and helpful. An intelligent and beautiful piece of work!
On Tuesday Jul 15 2008, J J Shah said:
Excellent work. Should be part of the standard pediatric echo report.
On Tuesday Jul 15 2008, Dan said:
@ Dr. Shah: My thoughts, exactly. Thanks for the kind words!
On Wednesday Jul 30 2008, Rabih Hamzeh said:
This is great Dan.
Aortic Root Z-Scores
Use this calculator to determine z-scores for the aortic valve and aortic root (sinus of Valsalva), using data from Boston Children's Hospital.
Per the authors, the technique used is: "Aortic annulus and root diameters were measured from parasternal long-axis images, with the aortic root diameter taken as the maximum dimension at the level of the sinuses... measured at the maximum systolic dimensions, from inner edge to inner edge."
Body surface area is calculated by the method of Haycock et al.
Also see: consolidated aortic root z-score calculator
| BSA: | |||||
| Site | Measurement | Mean | Range | Z-Score | Percentile |
|---|---|---|---|---|---|
References
Validation and re-evaluation of a discriminant model predicting anatomic suitability for biventricular repair in neonates with aortic stenosis. Colan SD, McElhinney DB, Crawford EC, Keane JF, Lock JE. J Am Coll Cardiol. 2006 May 2;47(9):1858-65.Previous Comments
On Thursday Feb 07 2008, DIANE HITCHCOCK said:
excellent and very easy to use!! I wish you had z-scores for LVID and LA in pediatrics
On Thursday Feb 07 2008, Dan said:
Thanks! As far as z-scores for the LV and LA- stay tuned. I am working on something that I think is going to work. In the meantime, try this
On Thursday Feb 14 2008, Kathy R. said:
Thank you for doing this; it's very helpful. The reference you provide, though, is for neonates with borderline LV size. Although I can get a z-score for whatever I put in, I wonder if your normative data extend to older children & teenagers. It's not just extrapolated from the babies, is it? Also, do you have any references for (or will you be adding) sinotubular jct. & AAo msmts, especially in older children? Thanks again for all your work.
On Thursday Feb 14 2008, Dan said:
Kathy: Thanks for your comments. As far as the z-scores relating to the population, it is my understanding that the authors provided us with the prediction equations for their normative data, as indicated by: ... on the basis of normative data obtained at our institution from children with structurally and functionally normal hearts [16]) were used instead ... To answer your other question about z scores for other measurement sites, this is the same question I have been asking... ParameterZ.com is only a small part of the answer.
On Thursday Feb 21 2008, Tim said:
No adjustment for age? This is not stratisfied according to sex either. Both of these have been shown to be main predictors of Aortic root size. See Roman and Devereux to determine your REAl z score. If you are an adult male over 40 years old the mean is 3.4cm +/- 0.3. Tis program understates by a healthey amount.
On Thursday Feb 21 2008, Dan said:
Questions about the cited study design and conclusions drawn (or not drawn) from the results should probably be directed to the authors (and not me). I am simply presenting the findings of the study relevant to the calculation of z-scores. Otherwise, if your are doubting the correctness or accuracy of the calculations themselves as presented here, please let me know. Thanks for the lead on the "Roman and Devereux" studies- I'll read up.
On Thursday Feb 21 2008, Dan said:
*later that same hour* regarding Roman and Devereux: The 1989 Am J Cardiol study is not a fair comparison to the data THIS calculator is based upon (2006 JACC) Roman et al. measured: using "leading edge technique", in diastole, using c.1989 equipment. The JACC 2006 study measured inside edge to inside edge, in systole (when the root is largest), using modern high resolution equipment. Further, Roman et al. studied what was then referred to as a"large sample size"-- 52 infants and children. The Boston data is based on "496 normal children and young adults" and is further based upon a theoretical and empirically derived allometric relationship. I maintain there is no comparison. It might be noteworthy to add that Roman and Devereux are both involved in the Marfan/losartan clinical trail, whose data will be normed, undoubtedly, using aortic root z-score data from Boston- the latest publication of which is represented here. Your mileage may vary.
On Tuesday Mar 18 2008, Tim said:
The problem is that aortic root diameters are measured as were done in Roman. This is the methedology used in almost all Cardilogist office. Thus these values could be confusing to some individuals if they are looking at their echo report!!!
On Tuesday Mar 18 2008, Dan said:
Great point Tim. One of the lessons I have learned about standardized scores is: technique is important! My entire focus with all of these z-score calculators is to provide reference information for pediatric echo, and as such, some of these calculations may not be relevant for other practice areas. If you are not using the same measurement technique as was used in the reference article, the z-scores will obviously not apply.
On Wednesday Apr 30 2008, M. said:
Wow. I'm not sure this is accurate? I mean, I've been plotting mine on the chart from my cardiologist and this calculator gives me a huge score!
On Thursday May 01 2008, Dan said:
@ "M.": Are you questioning the veracity of the calculations themselves, or the application of the calculations?
On Thursday May 29 2008, Nayana Parange said:
thank you for the calculators--I was wondering if you are aware of any data regarding fetal aortic root ultrasound measurements? cheers, Nayana
On Thursday May 29 2008, Dan said:
Nayana: I am personally unaware of any published z-score equations for the fetal aortic root, but wish you great luck in finding them.
On Thursday May 29 2008, Nayana said:
thanks for your prompt reply, Dan.
On Thursday Jun 12 2008, Maria Lapoint said:
Gracias por existir!
On Tuesday Jul 08 2008, Courtney L.Anthony, MD said:
Very useful
On Tuesday Jul 29 2008, JoAnn Puccella said:
At duPont Hospital for Children in Wilmington, DE we measure the Ao at the annulus, sinus, junction and ascending. Are z-scores acailable for those locations?
On Tuesday Jul 29 2008, Dan said:
JoAnn: The recent data from Michigan gets you z-scores for everything except the AAO, if you are comfortable with their model. Published equations for Z-Scores of the AAO are indeed rare.
On Friday Aug 01 2008, Bob Todd said:
nice, thanks
On Friday Aug 29 2008, Rejane said:
I got a few referrals for suspicion of fetal dilatation of the ascending aorta on routine ultrasound. We only find Z scores for the aortic annulus, but not for the supravalvar aorta, sinotubuluar junction and ascending aorta. Is there a source I'm not aware of? thanks so much for your help. I love these calculators you provide, keep up the good stuff... Rejane
On Friday Aug 29 2008, Dan said:
Rejane: Thanks for your comments. The calculator on this page will only calculate z-scores of the annulus and sinuses of valsalva ("aortic root"). ANOTHER calculator will give you z-scores for the annulus, sinuses, and ST junction. You are not mistaken- neither one has data for the AAO... I have yet to find a published source for AAO z-score equations.
Cardiac Valve Z-Scores
Determine z-scores for the mitral valve, aortic valve, tricuspid valve, and pulmonic valve using this calculator. The regression equations are those from Cincinnati Children's Hospital, based on over 700 children between the ages of 0-18 years.
| Location | Measured | Mean | Range | Z-Score |
|---|---|---|---|---|
Also see these derivative works:
- Mitral Valve Z-Score Table
- Tricuspid Valve Z-Score Table
- Aortic Valve Z-Score Table
- Pulmonary Valve Z-Score Table
References
Two-dimensional echocardiographic valve measurements in healthy children: gender-specific differences. Zilberman MV, Khoury PR, Kimball RT. Pediatr Cardiol. 2005 Jul-Aug;26(4):356-60. Erratum in: Pediatr Cardiol. 2008 Mar;29(2):475.
Previous Comments
On Friday Sep 28 2007, F Bennett Pearce, MD said:
very nice, if you could put a BSA calculator on the same page it would be even better
On Friday Sep 28 2007, Dan said:
Thanks, that's a good point- I will definitely add one.
I did not build one in initially, because there is no mention in the article about how the authors calculated their BSA for this study.
I can add one with a user-selectable choice for BSA formula...
*edit* I should learn to read more closely. The authors indeed disclose that the BSA is "calculated by Dubois formula"
On Sunday Sep 30 2007, Dan said:
added BSA calculation...
references:
Wikipedia and Steven B. Halls, MD.
Thanks for the suggestion.
Let me know if this doesn't suit the need.
On Friday Nov 09 2007, Paulo Manso, MD said:
Thank you This is a very useful tool Congratulations!
On Sunday Nov 11 2007, Dhamelisse Then said:
this will be very helpfull for us here, thanks a lot!!!!!!!!
On Sunday Nov 11 2007, Dan said:
I am glad you are finding it useful. Gracias a Ustedes!
On Wednesday Nov 14 2007, Dr Smita Mishra said:
Thanks. Thanks.It is very helpful. Please include Z score for pulmonary arterteries and ventricular dimensions. Smita Mishra Pediatric Cardiologist Max heart & vascular Institute, Saket New Delhi. India.
On Wednesday Nov 14 2007, Dan said:
I use the published literature as the source for these calculators... as yet, I have not found a suitable reference for the PA's or chamber sizes.
I welcome your suggestions though!
On Thursday Nov 29 2007, maitri chaudhuri said:
We would appreciate if you display the full range of pedaitric cardiac z scores. not only the valves
On Thursday Dec 06 2007, Sri Rao, MD said:
Very user-friendly, thank you so much.
On Friday Dec 07 2007, Dan said:
@ maitri: the z-scores from this calculator are based upon the Zilberman et al. article in Pediatric Cardiology- they only published z-scores for the valves.
@ Sri: You're welcome!
On Friday Feb 08 2008, SS Kothari said:
This is just fantastic.
On Thursday Mar 20 2008, Beverley said:
My son is 13 years old with a diagnosis of aortic stenosis ( mild to moderate) mild aortic insufficiency and a mod aortic root enlargement 3.5 cm. I was recently told he had a Z score of 6 and was asked to consider a beta blocker, this is a congenital diagnosis he does not have Marfans. I was wondering if you could give me an idea where to go to read more about how Z scores are scored and what that score means? Thanks so much!
On Thursday Mar 20 2008, Dan said:
Beverley: you should really discuss this with your son's pediatric cardiologist!
On Friday Mar 21 2008, Leslie A Flores, MD said:
Could you please add z scores for LVPW and IVS. Thanks!!!!!
On Saturday Apr 26 2008, Lily said:
Very useful, thanks!
On Tuesday May 27 2008, Nikola Tede MD said:
Great resource, thank you
On Monday Jun 30 2008, zhang yuqi said:
very good. thanks! i used to calculate Z score manually, it is clumsy.
On Wednesday Jul 16 2008, Jorge Faerron said:
Excellent. Thanks. Hospital Nacional de Ninos. Costa Rica.
On Wednesday Sep 10 2008, Jake Jaquiss said:
As a surgeon who is in the position of trying to achieve a certain z score with reconstruction, it would be helpful to be given small table with two columns: structure diameter and z score, for a given BSA. It would also be more consistent with clinical practice if the structure measurement input were in millmeters instead of centimeters, since that is how we size these valve on echo. These are vey minor bookkeeping issues, though. Overall, this is an absolutely terrific service you have provided to our community. Thank you very much.
On Wednesday Sep 10 2008, Dan said:
Dear Dr. Jaquiss:
Thanks for taking the time to provide your feedback on the z-score calculator.
From the perspective of the sonographer, the calculated z-score is just what gets the patient from the echo lab to you... I never thought to use the data from the other side of the coin (so to speak).
I'll be working on your proposed adaptation to the Cincinnati valve z-score data directly.
Thanks!
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