Skip to main content
NCBI home page
Annals of Pediatric Cardiology logoLink to Annals of Pediatric Cardiology
. 2023 Apr 4;16(1):11–17. doi: 10.4103/apc.apc_128_22

Echocardiographic nomograms and Z-scores for term Indian neonates

Vatsal Singh 1, Santhosh Satheesh 1, Sachit Ganapathy 2, Narayana-Pillai Sreekumaran Nair 2, Nivedita Mondal 3, Raja Selvaraj 1, Neeraj Mishra 3, Avinash Anantharaj 1,✉
PMCID: PMC10243653  PMID: 37287836

ABSTRACT

Background:

The availability of nomograms is crucial for the correct interpretation of pediatric and neonatal echocardiograms. Echocardiographic Z-score applications/websites use Western nomograms as reference, which may not be an appropriate standard for gauging Indian neonates. Currently available Indian pediatric nomograms either have not included neonates or have not been specifically designed for neonates. This gross underrepresentation of neonates renders available nomograms unreliable for use as standards for comparison.

Objectives:

The objective of this study was to collect normative data for the measurement of various cardiac structures using M-Mode and two-dimensional (2D) echo in healthy Indian neonates and to derive Z-scores for each measured parameter.

Methods:

Echocardiograms were performed on healthy term neonates (within first 5 days of life). Birth weight and length were recorded, and body surface area was calculated using Haycock’s formula. Twenty M-mode and 2D-echo parameters were measured (including left ventricular dimensions, atrioventricular valves, and semilunar valves’ annuli sizes, pulmonary artery and branches, aortic root, and arch).

Results:

We studied 142 neonates (73 males) with a mean age of 1.83 ± 1.12 days and mean birth weight of 2.89 ± 0.39 Kg. Regression equations with linear, logarithmic, exponential and square root models were tested to select the best model of fit for the relationship between birth weight and each echocardiographic parameter. Scatter plots and nomogram charts with Z-scores were prepared for each echocardiographic parameter.

Conclusions:

Our study provides nomograms with Z-scores for term Indian neonates weighing between 2 kg and 4 kg at birth, within first 5 days of life, for a set of echocardiographic parameters that are frequently used in clinical practice. This nomogram has poor predictability for babies at extremes of birth weight. There is a need for further indigenous studies to include neonates at extremes of weight, both term, and preterm.

Keywords: Echocardiography, Indian, neonates, pediatric echo, Z score

INTRODUCTION

The availability of nomograms is crucial for the correct interpretation of pediatric echocardiograms. As a neonate’s heart adapts to postnatal hemodynamics, relative sizes and flows across cardiac chambers change. It is, therefore, more challenging to diagnose abnormalities in this age group in comparison to a pediatric or an adult heart. Since the right ventricle is usually larger than the left ventricle (LV) at birth, it is not possible to use it as a reference to compare LV dimensions against it, as is done in adults. In the absence of age and body surface area (BSA) indexed normal reference values for LV, pathologies may go undetected. Nomograms are thus mandatory for reliable assessment of dimensions of cardiac chambers, valves, and great vessels, more so in the neonatal population.

At present, there are limited echocardiographic nomograms for Indian neonates. While performing neonatal echocardiograms, Z-score applications or websites are usually used to calculate the deviation of an echocardiographic measurement from the reference value.[1,2] While this practice may suit western countries, it might give wrong results, if done in India and other Asian countries as the reference nomograms included in these calculators are derived from Western data. Given the large variations in dimensions of cardiac structures (as is true for other organs as well) among different races, nomograms from the western population may not be suitable tools to gauge Indian neonates. The Indian population, in itself, is quite diverse, and ideally ethnicity-specific reference nomograms should be available. In addition, most echocardiographic studies have provided data for the pediatric population as a whole, including all children from birth to 18 years of age. Among them, the number of neonates included is either unspecified or is very less, translating into a gross under-representation of neonates.[3] We have summarized all the available studies in Appendix 1. Relatively more data are needed for neonates, considering their unique hemodynamics and the need for making early and accurate decisions regarding management if an abnormality is present.

Heterogeneity of results while applying different nomograms to an individual newborn is a cause for concern that advocates for the development of ethnicity specific nomograms. For example, for the same child, Z-score for mitral valve annulus (MVA) may range from − 1.63 to − 4.84 when different reference values are used.[4] Furthermore, most of the studies have provided nomograms for LV and valvular dimensions in neonates, while data on pulmonary arteries and aorta are limited.[4,5]

In view of the aforementioned limitations, there is a clear need for indigenous data on the echocardiographic parameters of the Indian neonatal population. This prospective study provides data for Indian neonatal echocardiographic nomograms along with Z-scores. Z-scores represent how many standard deviations (SDs) a value is higher or lower from the population mean and is considered the best method for assessing a value in a normally distributed population.[6]

METHODS

This was a cross-sectional observational study. We included consecutively born term neonates (within first 5 days of life). All children had APGAR score >7 at 1 min and at 5 min. The following neonates were excluded:

  1. Any congenital heart disease (except patent foramen ovale or small patent ductus arteriosus <2.5 mm within 1st 5 days of life)

  2. Any illness that required admission

  3. Suspected genetic syndromes, chromosomal abnormalities, inborn errors of metabolism

  4. Congenital heart disease detected antenatally by fetal echocardiogram

  5. Antenatally/postnatally diagnosed to have diseases of other organ systems that required continued hospitalization/surgery in the immediate newborn period

  6. Respiratory distress that required respiratory support in any form, including supplemental oxygen in the immediate newborn period, transient tachypnea of newborn

  7. Early onset sepsis

  8. Babies of mothers who had premature rupture of membranes/meconium-stained liquor.

Sample size calculation

Assuming a normal distribution of the variables and estimating the population SD at 1.7 mm (among all the echocardiographic parameters, aortic annulus size had a min SD of 1.7 mm) as seen on average in previous literature,[7] 124 subjects will be required to provide a 95% confidence interval with a margin of error of 0.3. Assuming that not all the echocardiographic studies would contain complete information, a higher subject number would be required. Assuming 10% of studies will have incomplete measurements, a total of 137 subjects was calculated.

Sampling technique: Consecutive inclusion

After obtaining informed consent, weight and length were measured. BSA was calculated using Haycock’s formula.[8] –BSA = 0.024265 × height (cm)0.3964 × weight (kg)0.5378. ECG-gated echocardiograms were performed using S8-3 probe of EPIQ 7G (Philips Medical System, Andover, MA) echocardiography machine in the Department of Cardiology. Loops were acquired by a qualified pediatric cardiologist and stored in digital imaging and communications in medicine format. Echocardiographic measurements were done offline as per the recommendations by Lopez et al.[9] Standard apical four chamber (A4C), parasternal long axis (PLAX), short axis, and suprasternal views were used to make all measurements. Neonates found to be having any congenital heart disease (except patent foramen ovale and small patent ductus arteriosus <2.5 mm) were excluded. Any study with an incomplete dataset was excluded from the analysis. No sedation was used before echocardiography. Mothers were encouraged to breastfeed their babies before the examination. Most babies were examined in the postfed state while they were tranquil or sleeping. Dextrose water was used to pacify babies who were crying. Our center does not practice swaddling newborns/use of pacifiers/nonnutritive sucking for echo examination, although these methods are being successfully used in other centers.

The following M-Mode parameters were recorded-

  1. Interventricular septum dimension in diastole

  2. LV internal dimension in diastole

  3. Left ventricle posterior wall dimension in diastole

  4. Interventricular septum dimension in systole

  5. LV internal dimension in systole

  6. LV posterior wall dimension in systole.

Following two-dimensional (2D)-echo parameters were recorded:

  1. Aortic valve annulus (AVA)

  2. Sinus of valsalva dimension

  3. Sino-tubular junction dimension

  4. Ascending aorta dimension (AscAo)

  5. Pulmonary valve annulus

  6. Main pulmonary artery dimension (MPA)

  7. Right pulmonary artery dimension

  8. Left pulmonary artery dimension

  9. Mitral valve annulus (PLAX view)

  10. Mitral valve annulus in apical 4-chamber view

  11. Tricuspid valve annulus in 4-chamber view (TVA)

  12. Aortic arch proximal

  13. Aortic arch distal

  14. Aortic arch isthmus.

Ethics

The study was approved by the Institute ethics committee. Informed consent was obtained from either of the parents of each baby enrolled in the study.

Statistics

The mean and SD of all echocardiographic parameters were measured. Using IBM SPSS Statistics for Windows, Version 19 (IBM Corp, Armonk, N.Y., USA), regression equations with linear, logarithmic, exponential, and square root models were tested to examine the relationship between birth weight and each of the echocardiographic variables. The models with the highest R2 value for each echocardiographic variable were selected. Using STATA software “(Stata Statistical Software. College Station, TX: StataCorp), birth weight-adjusted nomogram charts (with Z-scores) were prepared for each echocardiographic parameter using the model with the best fit.

RESULTS

We assessed the echocardiograms of 142 neonates (73 were male). All echocardiographic examinations were done within the first 5 days of life. Data on average age, birth weight, length, and BSA is provided in Table 1. The mean values and SD for the 20 assessed echocardiographic parameters are provided in Table 2. Figures 1-4 show scatter plots for TVA, AVA, MPA, and AscAo as per birth weight. Scatter plots for the other echocardiographic parameters are provided in Appendix 2.

Table 1.

Basic characteristics of the entire cohort (n=142)

Character Value
Age (in days) mean +/- SD 1.83±1.12
Number of male babies n(%) 73 (51.4)
Number of female babies n(%) 69 (48.6)
Weight (kg) mean +/-SD 2.8±0.39
Length (cm) mean +/-SD 49.47±1.97
BSA (m2) mean +/-SD 0.20±0.02
Open in a new tab

BSA: Body surface area, SD: Standard deviation

Table 2.

Echocardiographic parameters of the entire cohort (n=142)

Parameter (mm) Mean±SD Minimum Maximum
TV annulus 10.93±1.24 8.4 14.5
MV annulus (A4C) 9.14±1.08 6.9 12.4
MV annulus (PLAX) 9.78±1.37 6.6 13.5
IVS in diastole 3.75±0.78 2 5.7
LVID in diastole 15.97±2.36 10.1 26.2
LVPW in diastole 3.06±0.60 1.7 5
IVS in systole 5.46±0.99 3.1 7.8
LVID in systole 10.47±2.13 5.4 19.3
LVPW in systole 4.63±0.84 2.4 7.5
PV annulus 6.80±0.96 4.7 9.3
Main PA 8.02±1.30 4.8 12.3
Right PA 4.45±0.63 3.2 6.4
Left PA 4.72±0.80 3.2 7.8
AV annulus 6.30±0.72 4.7 8.4
Aortic root 9.16±0.83 7.5 10.9
Sino-tubular junction 7.02±0.76 5.3 9
Ascending aorta 7.86±1.02 3.9 9.8
Aortic arch proximal 6.99±0.78 5.2 8.7
Aortic arch distal 5.98±0.79 4.2 7.9
Aortic arch isthmus 4.44±0.65 3.1 6.3
Open in a new tab

SD: Standard deviation, TV: Tricuspid valve, MV: Mitral valve, 4CV: 4-chamber view, PLAX: Parasternal long axis, IVS: Interventricular septum, LVID: Left ventricle internal dimension, LVPW: Left ventricle posterior wall, PV: Pulmonary valve, PA: Pulmonary artery, AV: Aortic valve

Figure 1.

Figure 1

Open in a new tab

Scatter plot showing distribution of TVA dimensions as per birth weight. TVA: Tricuspid valve annulus

Figure 4.

Figure 4

Open in a new tab

Scatter plot showing distribution of AscAo dimensions as per birth weight. AscAo: Ascending aorta dimension

Figure 2.

Figure 2

Open in a new tab

Scatter plot showing distribution of AVA dimensions as per birth weight. AVA : Aortic valve annulus

Figure 3.

Figure 3

Open in a new tab

Scatter plot showing distribution of MPA dimensions as per birth weight. MPA: Main pulmonary artery

Using regression equations, various models (linear, logarithmic, exponential, and square root) were created to predict the echocardiographic parameters by birth weight. Models with best fit (max R2 values) have been provided in Table 3. Prediction charts for TVA, AVA, MPA, and AscAo as per birth weight are shown in Figures 5-8. Prediction charts for all parameters are available in Appendix 3.

Table 3.

Best models for prediction of the measured echocardiographic parameters

Parameter Intercept Β SE-β MSE KS test statistic P R 2 Model of fit
TV annulus 7.58 3.31 0.88 1.48 0.075 0.185 0.125 Model: y=a + bln (x)
MV annulus (A4C) 6.49 2.6 0.77 1.13 0.064 0.2 0.103 Model: y=a + bln (x)
MV annulus (PLAX) 2.02 0.26 0.1 0.017 0.045 0.2 0.068 Model: ln (y)=a+bln (x)
IVS in diastole 0.96 0.32 0.15 0.044 0.069 0.2 0.043 Model: ln (y)=a+bln (x)
LVID in diastole 2.53 0.21 0.11 0.023 0.083 0.086 0.036 Model: ln (y)=a+bln (x)
LVPW in diastole 0.53 0.19 0.05 0.04 0.066 0.2 0.129 Model: ln (y)=a+bx
IVS in systole 2.36 1.83 0.82 0.9 0.061 0.2 0.049 Model: y=a + b sqrt (x)
LVID in systole 2.25 0.07 0.15 0.043 0.091 0.039 0.002 Model: ln (y)=a+bln (x)
LVPW in systole 2.98 0.57 0.22 0.78 0.087 0.058 0.061 Model: y=a + bx
PV annulus 1.57 0.35 0.1 0.018 0.076 0.168 0.116 Model: ln (y)=a+bln (x)
Main PA 2.37 0.28 0.19 0.051 0.05 0.2 0.021 Model: sqrt (y)=a+b sqrt (x)
Right PA 1.43 0.08 0.1 0.02 0.077 0.15 0.006 Model: ln (y)=a+bln (x)
Left PA 1.47 0.1 0.12 0.027 0.054 0.2 0.007 Model: ln (y)=a+bln (x)
AV annulus 4.27 1.99 0.45 0.39 0.057 0.2 0.166 Model: y=a + bln (x)
Aortic root 7.31 1.84 0.55 0.57 0.06 0.2 0.103 Model: y=a + bln (x)
Sino-tubular junction 5.19 1.68 0.54 0.55 0.051 0.2 0.091 Model: y=a + bln (x)
Ascending aorta 1.72 0.33 0.06 0.008 0.05 0.2 0.216 Model: ln (y)=a+bln (x)
Aortic arch proximal 6.67 0.5 0.49 0.45 0.056 0.2 0.011 Model: y=a + bln (x)
Aortic arch distal 1.74 0.07 0.09 0.014 0.059 0.2 0.007 Model: ln (y)=a+bln (x)
Aortic arch isthmus 3.78 0.76 0.46 0.41 0.041 0.2 0.026 Model: y=a + bln (x)
Open in a new tab

TV: Tricuspid valve, MV: Mitral valve, A4C-Apical 4 chamber view, PLAX: Parasternal long axis, IVS: Interventricular septum, LVID: Left ventricle internal dimension, LVPW: Left ventricle posterior wall, PV: Pulmonary valve, PA: Pulmonary artery, AV: Aortic valve, SE: Standard error, KS: Kolmogorov–Smirnov, MSE: Mean squared error

Figure 5.

Figure 5

Open in a new tab

Prediction chart for TVA using weight. TVA: Tricuspid valve annulus

Figure 8.

Figure 8

Open in a new tab

Prediction chart AscAo for using weight. AscAo: Ascending aorta dimension

Figure 6.

Figure 6

Open in a new tab

Prediction chart for AVA using weight. AVA: Aortic valve annulus

Figure 7.

Figure 7

Open in a new tab

Prediction chart for MPA using weight. MPA: Main pulmonary artery

DISCUSSION

We included 142 neonates within first 5 days of life. The mean age was 1.83 ± 1.12 days. We assessed 20 variables that are considered most important for a routine echocardiographic examination. Echocardiographic measurements in neonates with congenital heart disease are critical for decision-making regarding the need for and timing of surgery/interventional therapy.

The study by Trivedi et al. included 132 neonates and assessed most echocardiographic parameters relevant for decision-making in pediatric cardiology practice.[10] Z-scores for children from the newborn period to 16 years of age correlated with BSA were provided. Details regarding the newborn subset including the number of term versus preterm babies in the cohort of 132, number of small for gestational age (SGA) versus appropriate for gestational age versus large for gestational age (LGA) babies, average age in mean days of life when the echocardiography examination was performed were not elaborated upon. Jain et al. did echocardiograms for 50 neonates on day 1 and day 2 of life and measured right ventricular parameters.[11] The study by Tacy et al. was the earliest to provide reference values for valvular annuli for 70 neonates, including both preterms and terms.[12] Many newborns had very low birth weight. Solinger et al. provided cardiac chamber dimensions at a time when 2D echocardiography had not come into vogue.[13] They had included 240 neonates within 1st week of life. In addition, there have been a few pediatric echocardiographic studies designed for establishing nomograms across a wide age group, that also incorporated adequate focus on neonates.[7,14]

Most of the echocardiographic measurements correlate with body weight and BSA. As birth weight has more variability in comparison to BSA in the newborn period and since length measurement is prone to error in neonates,[11] birth weight is preferred over BSA for indexing echocardiographic measurements. The weight of neonates in our study ranged from 1.96 to 4.0 kg, and BSA ranged from 0.16 to 0.24 m2. This narrow range led to a homogenous study cohort which was also the result of including exclusively term newborns within the first 5 days of life. The SD for weight for our neonates was only 0.39 kg. This led to weak statistical correlations between echocardiographic parameters and birth weight. The regression analysis showed that birth weight had low predictability for echocardiographic parameters in our study. Maximum predictability was found for AscAo (21.6%). However, in our study, the variability of echocardiographic parameters in relation to BSA (as shown in scatterplots) was comparable to the study by Trivedi et al.[10] Although Cantinotti et al.[7] have shown that BSA can be a suitable standard for young infants too, in a cohort like ours with minimal variation of BSA, weight was a more suitable standard. Since neonates are under-represented in most pediatric nomograms, reliability of those for providing the answers in neonates is questionable, signifying the need for prospectively designed studies for establishing neonatal nomograms. Although the pediatric heart network database[14] demonstrated the generalizability of their nomogram to children of various races and ethnic backgrounds residing in North America, whether it holds true universally is to be tested, more so since evidence revealing significant differences on comparing an Indian pediatric echocardiographic nomogram[15] against Western literature is available.[16] When left ventricular and left atrial chamber dimensions in older children and adolescents assessed by established nomograms [including American, European, African and Asian (Indian and Japanese)] were compared, significant differences were identified.[16] Unless validated by large-scale studies in Asian and African populations, the practice of applying Western literature to children from these countries might lead to erroneous conclusions and decisions. Whether race plays an insignificant role in determining cardiac dimensions needs to be studied in children, especially since evidence to the contrary is available in adults.[17] It may be interesting to note that left ventricular volumes and dimensions were significantly lower in Asians in comparison to Europeans[17] in adults, similar to what was revealed by the analysis of Majonga et al.[16] in children.

There is a need to sample more neonates with extremes of birth weight like pre-terms and large for gestational age babies to give accurate weight adjusted models. In recent years, studies have been done to provide Z-scores exclusively for preterms, which is an encouraging trend. Abushaban et al. have given reference values for LV dimensions,[18] cardiac annuli,[19] and LV mass[20] while Dijkema et al. have provided reference values for aortic arch dimensions[21] in preterm neonates. The reference data provided by our study can be reliably used for term Indian neonates within 2–4 kg of birth weight.

Limitations

This study includes a dataset specific for term Indian neonates within 2–4 kg of birth weight. However, due to the narrow range of birth weights included, the birth weight-based models have low predictability for echocardiographic dimensions for very low or very high birth weight neonates. Therefore, the reference data may not be applicable to SGA or LGA neonates.

CONCLUSIONS

Nomograms for a wide variety of parameters measured during the routine echocardiographic examination that are necessary for critical decision-making at/soon after birth have been provided. These nomograms apply to Indian neonates weighing between 2 kg and 4 kg at birth, within the first 5 days of life. These nomograms have poor predictability for babies at extremes of weight. There is a need for further indigenous studies to include neonates at extremes of weight, both term and preterm.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Acknowledgment

Vatsal Singh was awarded Savitri Srivasthava imaging award by the Pediatric Cardiac Society of India for this study which is gratefully acknowledged.

APPENDIXES

Appendix 1.

Studies on echocardiographic nomograms for pediatric population (some include neonates)

Year Author Location n Age group Echocardiographic parameters
1973 Solinger et al.[1] USA 240 Neonates 4 chambers A mode and M mode
1984 Snider et al.[2] USA 110 <18 years AV, PV
1985 King et al.[3] USA 103 <15 years MV, TV
1988 Hanséus et al.[4] Sweden 120 <16 years 4 chambers, great vessels, IVC
1995 Tacy et al.[5] USA 70 Neonates <10 days MV, AV, TV, PV
1998 Skelton et al.[6] UK 79 Preterm <34 weeks LA, LV, aortic root, Vmax all 4 valves
1999 Daubeney et al.[7] UK, Australia 125 <18 years TV, RV, PA, MV, aortic root
2000 Kampmann et al.[8] Germany 2036 <18 years M-mode: LV and RV, LA, PV, AV
2001 Eidem et al.[9] USA 325 <18 years TDI MV lateral and medial, TV lateral
2005 Zilberman et al.[10] USA 748 <18 years MV, AV, TV, PV
2006 Warren et al.[11] Canada 88 <18 years with bicuspid AV Ascending aorta (in isolated bicuspid aortic valve)
2006 Overbeek et al.[12] Netherlands 587 <18 years M-mode: LV
2008 Foster et al.[13] Canada 239 <21 years M-mode: LV mass
2008 Pettersen et al.[14] USA 782 <18 years Aortic root, arch, PV, PA, MV, TV, LA
2009 Koestenberger et al.[15] Austria 640 <18 years TAPSE
2009 Neilan et al.[16] USA 4109 <18 years LA
2010 Gautier et al.[17] France 353 <18 years Aortic root, ascending aorta
2011 Dallaire and Dahdah [18] Canada 1033 Children Coronaries
2011 Lytrivi et al.[19] Greece 100 <3 years LVEDV
2012 Bhatla et al.[20] USA 300 <18 years Left atrial volume
2012 Koestenberger et al.[21] Austria 860 <18 years TAPSV
2014 Campens et al.[22] Belgium 133 <15 years Aortic root, ascending aorta
2015 Dallaire et al.[23] Canada 1422 <18 years Proximal aorta
2014 Jain et al.[24] Canada 50 Term newborns, day 1, 2 RV dimensions and function, TV, LV, TDI, TAPSE, strain
2014 Cantinotti et al.[25] Italy 1091 <17 years LA, LV, RA, RV diameters and areas
2014 Cantinotti et al.[26] Italy 445 <2.5 years AV, aortic root, arch, IVC, PV, PA, MV, TV, LV, LVEF
2014 Abushaban et al.[27] Kuwait 268 Preterms LV dimensions
2015 Hussain et al.[28] UK 50 18 days-18 years Coronaries
2015 Dallaire et al.[29] Canada 233 1-18 years PW Doppler MV, LVOT; MPI; color TDI
2015 Fibbi et al.[30] Italy 369 <17 years LV TDI
2017 Cantinotti et al.[31] Italy 1151 <17 years AV, aortic root, arch, IVC, PV, PA, MV, TV
2016 Kobayashi et al.[32] Japan 3851 <18 years Coronaries
2016 Abushaban et al.[33] Kuwait 268 Preterms Valvular annuli
2017 Dijkema et al.[34] Netherlands 385 Preterm <32 weeks Aortic arch
2017 Gokhroo et al.[35] Ajmer, Mohali India 746 4-15 years Aortic root, ascending aorta, MV, TV, LA, RA, RV, LV dimensions
2017 Lopez et al.[36] USA 3566 <18 years PV, PA, Aortic root, ascending aorta, arch, MV, TV, coronaries, LV dimensions, area
2017 Majonga et al.[37] Zimbabwe 282 6–16 years M Mode-LA, LV, RV, TAPSE
2018 Rajagopal et al.[38] USA 300 <18 years (50 were<1 year) RA area by 2D and 3D echo
2017 Choudhry et al.[39] USA 503 Preterm <2 kg M mode LV
2018 Van Ark et al.[40] Netherlands 376 Preterm <32 weeks <2 kg AV, PV, MV, TV
2019 Krysztofiak et al.[41] Poland 791 5-18 years LV mass
2020 Abushaban et al.[42] Kuwait 268 Preterm<36 weeks LV mass and index
2018 Trivedi et al.[43] MH, India 596 <16 years (132 neonates) MV, TV, PV, PA, aortic root, arch, M-mode: LV
Open in a new tab

AV: Aortic valve, PV: Pulmonary valve, MV: Mitral valve, TV: Tricuspid valve, IVC: Inferior vena cava, LA: Left atrium, LV: Left ventricle, LVEDV: LV end diastolic volume, RA: Right atrium, RV: Right ventricle, PA: Pulmonary artery, TAPSE: Tricuspid annular peak systolic excursion, TAPSV: Tricuspid annular peak systolic velocity, TDI: Tissue Doppler imaging, PW: Pulse wave, LVEF: LV ejection fraction

Appendix 2: Scatter plots for all echocardiographic parameters

graphic file with name APC-16-11-g009.jpg

Appendix 3: Prediction charts for all echocardiographic parameters were prepared, shown from Figures 21 to 40

graphic file with name APC-16-11-g010.jpg

REFERENCES

  • 1.Parameterz.com. 2019. [[Last accessed on 2019 Apr 11]]. Available from:http://www.parameterz.com/
  • 2.Z-Score Calculator Baby Heart. 2019. [[Last accessed on 2019 Apr 11]]. Available from:http://babyheart.in/category/medical/z-score-calculator/
  • 3.Cantinotti M, Assanta N, Crocetti M, Marotta M, Murzi B, Iervasi G. Limitations of current nomograms in pediatric echocardiography: Just the tip of the iceberg –A call for standardization. J Am Soc Echocardiogr. 2014;27:339. doi: 10.1016/j.echo.2013.12.002. [DOI] [PubMed] [Google Scholar]
  • 4.Pettersen MD, Du W, Skeens ME, Humes RA. Regression equations for calculation of z scores of cardiac structures in a large cohort of healthy infants, children, and adolescents: An echocardiographic study. J Am Soc Echocardiogr. 2008;21:922–34. doi: 10.1016/j.echo.2008.02.006. [DOI] [PubMed] [Google Scholar]
  • 5.Sluysmans T, Colan SD. Theoretical and empirical derivation of cardiovascular allometric relationships in children. J Appl Physiol (1985) 2005;99:445–57. doi: 10.1152/japplphysiol.01144.2004. [DOI] [PubMed] [Google Scholar]
  • 6.Colan SD. The why and how of Z scores. J Am Soc Echocardiogr. 2013;26:38–40. doi: 10.1016/j.echo.2012.11.005. [DOI] [PubMed] [Google Scholar]
  • 7.Cantinotti M, Scalese M, Murzi B, Assanta N, Spadoni I, Festa P, et al. Echocardiographic nomograms for ventricular, valvular and arterial dimensions in Caucasian children with a special focus on neonates, infants and toddlers. J Am Soc Echocardiogr. 2014;27:179–91. doi: 10.1016/j.echo.2013.10.001. e2. [DOI] [PubMed] [Google Scholar]
  • 8.Haycock GB, Schwartz GJ, Wisotsky DH. Geometric method for measuring body surface area: A height-weight formula validated in infants, children, and adults. J Pediatr. 1978;93:62–6. doi: 10.1016/s0022-3476(78)80601-5. [DOI] [PubMed] [Google Scholar]
  • 9.Lopez L, Colan SD, Frommelt PC, Ensing GJ, Kendall K, Younoszai AK, et al. Recommendations for quantification methods during the performance of a pediatric echocardiogram: A report from the Pediatric Measurements Writing Group of the American Society of Echocardiography Pediatric and Congenital Heart Disease Council. J Am Soc Echocardiogr. 2010;23:465–95. doi: 10.1016/j.echo.2010.03.019. [DOI] [PubMed] [Google Scholar]
  • 10.Trivedi B, Chokhandre M, Dhobe P, Garekar S. Estimation of Z-scores of cardiac structures in healthy Indian pediatric population. J Indian Acad Echocardiogr Cardiovasc Imaging. 2018;2:147–54. [Google Scholar]
  • 11.Jain A, Mohamed A, El-Khuffash A, Connelly KA, Dallaire F, Jankov RP, et al. A comprehensive echocardiographic protocol for assessing neonatal right ventricular dimensions and function in the transitional period: Normative data and z scores. J Am Soc Echocardiogr. 2014;27:1293–304. doi: 10.1016/j.echo.2014.08.018. [DOI] [PubMed] [Google Scholar]
  • 12.Tacy TA, Vermilion RP, Ludomirsky A. Range of normal valve annulus size in neonates. Am J Cardiol. 1995;75:541–3. doi: 10.1016/s0002-9149(99)80605-5. [DOI] [PubMed] [Google Scholar]
  • 13.Solinger R, Elbl F, Minhas K. Echocardiography in the normal neonate. Circulation. 1973;47:108–18. doi: 10.1161/01.cir.47.1.108. [DOI] [PubMed] [Google Scholar]
  • 14.Lopez L, Colan S, Stylianou M, Granger S, Trachtenberg F, Frommelt P, et al. Relationship of echocardiographic Z scores adjusted for body surface area to age, sex, race, and ethnicity: The pediatric heart network normal echocardiogram database. Circ Cardiovasc Imaging. 2017;10:e006979. doi: 10.1161/CIRCIMAGING.117.006979. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 15.Gokhroo RK, Anantharaj A, Bisht D, Kishor K, Plakkal N, Aghoram R, et al. A pediatric echocardiographic Z-score nomogram for a developing country: Indian pediatric echocardiography study –The Z-score. Ann Pediatr Cardiol. 2017;10:31–8. doi: 10.4103/0974-2069.197053. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 16.Majonga ED, Norrish G, Rehman AM, Kranzer K, Mujuru HA, Nathoo K, et al. Racial variation in echocardiographic reference ranges for left chamber dimensions in children and adolescents: A systematic review. Pediatr Cardiol. 2018;39:859–68. doi: 10.1007/s00246-018-1873-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 17.Echocardiographic Normal Ranges Meta-Analysis of the Left Heart Collaboration. Ethnic-specific normative reference values for echocardiographic LA and LV Size, LV Mass, and systolic function: The EchoNoRMAL study. JACC Cardiovasc Imaging. 2015;8:656–65. doi: 10.1016/j.jcmg.2015.02.014. [DOI] [PubMed] [Google Scholar]
  • 18.Abushaban L, Vel MT, Rathinasamy J, Sharma PN. Normal reference ranges for left ventricular dimensions in preterm infants. Ann Pediatr Cardiol. 2014;7:180–6. doi: 10.4103/0974-2069.140832. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 19.Abushaban L, Vel MT, Rathinasamy J, Sharma PN. Normal reference ranges for cardiac valve annulus in preterm infants. Pediatr Cardiol. 2016;37:112–9. doi: 10.1007/s00246-015-1247-9. [DOI] [PubMed] [Google Scholar]
  • 20.Abushaban L, Rathinasamy J, Sharma PN, Vel MT. Normal reference ranges for the left ventricular mass and left ventricular mass index in preterm infants. Ann Pediatr Cardiol. 2020;13:25–30. doi: 10.4103/apc.APC_171_18. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 21.Dijkema EJ, Molenschot MC, Breur JM, de Vries WB, Slieker MG. Normative values of aortic arch structures in premature infants. J Am Soc Echocardiogr. 2017;30:227–32. doi: 10.1016/j.echo.2016.11.016. [DOI] [PubMed] [Google Scholar]
  • 22.Solinger R, Elbl F, Minhas K. Echocardiography in the normal neonate. Circulation. 1973;47:108–18. doi: 10.1161/01.cir.47.1.108. [DOI] [PubMed] [Google Scholar]
  • 23.Snider AR, Enderlein MA, Teitel DF, Juster RP. Two-dimensional echocardiographic determination of aortic and pulmonary artery sizes from infancy to adulthood in normal subjects. Am J Cardiol. 1984;53:218–24. doi: 10.1016/0002-9149(84)90715-x. [DOI] [PubMed] [Google Scholar]
  • 24.King DH, Smith EO, Huhta JC, Gutgesell HP. Mitral and tricuspid valve anular diameter in normal children determined by two-dimensional echocardiography. Am J Cardiol. 1985;55:787–9. doi: 10.1016/0002-9149(85)90157-2. [DOI] [PubMed] [Google Scholar]
  • 25.Hanséus K, Björkhem G, Lundström NR. Dimensions of cardiac chambers and great vessels by cross-sectional echocardiography in infants and children. Pediatr Cardiol. 1988;9:7–15. doi: 10.1007/BF02279877. [DOI] [PubMed] [Google Scholar]
  • 26.Tacy TA, Vermilion RP, Ludomirsky A. Range of normal valve annulus size in neonates. Am J Cardiol. 1995;75:541–3. doi: 10.1016/s0002-9149(99)80605-5. [DOI] [PubMed] [Google Scholar]
  • 27.Skelton R, Gill AB, Parsons JM. Reference ranges for cardiac dimensions and blood flow velocity in preterm infants. Heart. 1998;80:281–5. doi: 10.1136/hrt.80.3.281. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 28.Daubeney PE, Blackstone EH, Weintraub RG, Slavik Z, Scanlon J, Webber SA. Relationship of the dimension of cardiac structures to body size: An echocardiographic study in normal infants and children. Cardiol Young. 1999;9:402–10. doi: 10.1017/s1047951100005217. [DOI] [PubMed] [Google Scholar]
  • 29.Kampmann C, Wiethoff CM, Wenzel A, Stolz G, Betancor M, Wippermann CF, et al. Normal values of M mode echocardiographic measurements of more than 2000 healthy infants and children in central Europe. Heart. 2000;83:667–72. doi: 10.1136/heart.83.6.667. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 30.Eidem BW, McMahon CJ, Cohen RR, Wu J, Finkelshteyn I, Kovalchin JP, et al. Impact of cardiac growth on Doppler tissue imaging velocities: A study in healthy children. J Am Soc Echocardiogr. 2004;17:212–21. doi: 10.1016/j.echo.2003.12.005. [DOI] [PubMed] [Google Scholar]
  • 31.Zilberman MV, Khoury PR, Kimball RT. Two-dimensional echocardiographic valve measurements in healthy children: Gender-specific differences. Pediatr Cardiol. 2005;26:356–60. doi: 10.1007/s00246-004-0736-z. [DOI] [PubMed] [Google Scholar]
  • 32.Warren AE, Boyd ML, O'Connell C, Dodds L. Dilatation of the ascending aorta in paediatric patients with bicuspid aortic valve: Frequency, rate of progression and risk factors. Heart. 2006;92:1496–500. doi: 10.1136/hrt.2005.081539. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 33.Overbeek LI, Kapusta L, Peer PG, de Korte CL, Thijssen JM, Daniels O. New reference values for echocardiographic dimensions of healthy Dutch children. Eur J Echocardiogr. 2006;7:113–21. doi: 10.1016/j.euje.2005.03.012. [DOI] [PubMed] [Google Scholar]
  • 34.Foster BJ, Mackie AS, Mitsnefes M, Ali H, Mamber S, Colan SD. A novel method of expressing left ventricular mass relative to body size in children. Circulation. 2008;117:2769–75. doi: 10.1161/CIRCULATIONAHA.107.741157. [DOI] [PubMed] [Google Scholar]
  • 35.Pettersen MD, Du W, Skeens ME, Humes RA. Regression equations for calculation of z scores of cardiac structures in a large cohort of healthy infants, children, and adolescents: An echocardiographic study. J Am Soc Echocardiogr. 2008;21:922–34. doi: 10.1016/j.echo.2008.02.006. [DOI] [PubMed] [Google Scholar]
  • 36.Koestenberger M, Ravekes W, Everett AD, Stueger HP, Heinzl B, Gamillscheg A, et al. Right ventricular function in infants, children and adolescents: Reference values of the tricuspid annular plane systolic excursion (TAPSE) in 640 healthy patients and calculation of z score values. J Am Soc Echocardiogr. 2009;22:715–9. doi: 10.1016/j.echo.2009.03.026. [DOI] [PubMed] [Google Scholar]
  • 37.Neilan TG, Pradhan AD, King ME, Weyman AE. Derivation of a size-independent variable for scaling of cardiac dimensions in a normal paediatric population. Eur J Echocardiogr. 2009;10:50–5. doi: 10.1093/ejechocard/jen110. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 38.Gautier M, Detaint D, Fermanian C, Aegerter P, Delorme G, Arnoult F, et al. Nomograms for aortic root diameters in children using two-dimensional echocardiography. Am J Cardiol. 2010;105:888–94. doi: 10.1016/j.amjcard.2009.11.040. [DOI] [PubMed] [Google Scholar]
  • 39.Dallaire F, Dahdah N. New equations and a critical appraisal of coronary artery Z scores in healthy children. J Am Soc Echocardiogr. 2011;24:60–74. doi: 10.1016/j.echo.2010.10.004. [DOI] [PubMed] [Google Scholar]
  • 40.Lytrivi ID, Bhatla P, Ko HH, Yau J, Geiger MK, Walsh R, et al. Normal values for left ventricular volume in infants and young children by the echocardiographic subxiphoid five-sixth area by length (bullet) method. J Am Soc Echocardiogr. 2011;24:214–8. doi: 10.1016/j.echo.2010.12.002. [DOI] [PubMed] [Google Scholar]
  • 41.Bhatla P, Nielsen JC, Ko HH, Doucette J, Lytrivi ID, Srivastava S. Normal values of left atrial volume in pediatric age group using a validated allometric model. Circ Cardiovasc Imaging. 2012;5:791–6. doi: 10.1161/CIRCIMAGING.112.974428. [DOI] [PubMed] [Google Scholar]
  • 42.Koestenberger M, Nagel B, Ravekes W, Avian A, Heinzl B, Cvirn G, et al. Reference values of tricuspid annular peak systolic velocity in healthy pediatric patients, calculation of z score, and comparison to tricuspid annular plane systolic excursion. Am J Cardiol. 2012;109:116–21. doi: 10.1016/j.amjcard.2011.08.013. [DOI] [PubMed] [Google Scholar]
  • 43.Campens L, Demulier L, De Groote K, Vandekerckhove K, De Wolf D, Roman MJ, et al. Reference values for echocardiographic assessment of the diameter of the aortic root and ascending aorta spanning all age categories. Am J Cardiol. 2014;114:914–20. doi: 10.1016/j.amjcard.2014.06.024. [DOI] [PubMed] [Google Scholar]
  • 44.Dallaire F, Bigras JL, Prsa M, Dahdah N. Bias related to body mass index in pediatric echocardiographic Z scores. Pediatr Cardiol. 2015;36:667–76. doi: 10.1007/s00246-014-1063-7. [DOI] [PubMed] [Google Scholar]
  • 45.Jain A, Mohamed A, El-Khuffash A, Connelly KA, Dallaire F, Jankov RP, et al. A comprehensive echocardiographic protocol for assessing neonatal right ventricular dimensions and function in the transitional period: Normative data and z scores. J Am Soc Echocardiogr. 2014;27:1293–304. doi: 10.1016/j.echo.2014.08.018. [DOI] [PubMed] [Google Scholar]
  • 46.Cantinotti M, Scalese M, Murzi B, Assanta N, Spadoni I, De Lucia V, et al. Echocardiographic nomograms for chamber diameters and areas in Caucasian children. J Am Soc Echocardiogr. 2014;27:1279–92.e2. doi: 10.1016/j.echo.2014.08.005. [DOI] [PubMed] [Google Scholar]
  • 47.Cantinotti M, Scalese M, Murzi B, Assanta N, Spadoni I, Festa P, et al. Echocardiographic nomograms for ventricular, valvular and arterial dimensions in caucasian children with a special focus on neonates, infants and toddlers. J Am Soc Echocardiogr. 2014;27:179–91.e2. doi: 10.1016/j.echo.2013.10.001. [DOI] [PubMed] [Google Scholar]
  • 48.Abushaban L, Vel MT, Rathinasamy J, Sharma PN. Normal reference ranges for left ventricular dimensions in preterm infants. Ann Pediatr Cardiol. 2014;7:180–6. doi: 10.4103/0974-2069.140832. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 49.Hussain T, Mathur S, Peel SA, Valverde I, Bilska K, Henningsson M, et al. Coronary artery size and origin imaging in children: A comparative study of MRI and trans-thoracic echocardiography. BMC Med Imaging. 2015;15:48. doi: 10.1186/s12880-015-0095-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 50.Dallaire F, Slorach C, Hui W, Sarkola T, Friedberg MK, Bradley TJ, et al. Reference values for pulse wave Doppler and tissue Doppler imaging in pediatric echocardiography. Circ Cardiovasc Imaging. 2015;8:e002167. doi: 10.1161/CIRCIMAGING.114.002167. [DOI] [PubMed] [Google Scholar]
  • 51.Fibbi V, Ballo P, Favilli S, Spaziani G, Calabri GB, Pollini I, et al. Determinants and regression equations for the calculation of z scores of left ventricular tissue doppler longitudinal indexes in a healthy Italian pediatric population. Cardiol Res Pract. 2015;2015:380729. doi: 10.1155/2015/380729. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 52.Cantinotti M, Giordano R, Scalese M, Murzi B, Assanta N, Spadoni I, et al. Nomograms for two-dimensional echocardiography derived valvular and arterial dimensions in Caucasian children. J Cardiol. 2017;69:208–15. doi: 10.1016/j.jjcc.2016.03.010. [DOI] [PubMed] [Google Scholar]
  • 53.Kobayashi T, Fuse S, Sakamoto N, Mikami M, Ogawa S, Hamaoka K, et al. A New Z Score Curve of the Coronary Arterial Internal Diameter Using the Lambda-Mu-Sigma Method in a Pediatric Population. J Am Soc Echocardiogr. 2016;29:794–801.e29. doi: 10.1016/j.echo.2016.03.017. [DOI] [PubMed] [Google Scholar]
  • 54.Abushaban L, Vel MT, Rathinasamy J, Sharma PN. Normal Reference Ranges for Cardiac Valve Annulus in Preterm Infants. Pediatr Cardiol. 2016;37:112–9. doi: 10.1007/s00246-015-1247-9. [DOI] [PubMed] [Google Scholar]
  • 55.Dijkema EJ, Molenschot MC, Breur JM, de Vries WB, Slieker MG. Normative values of aortic arch structures in premature infants. J Am Soc Echocardiogr. 2017;30:227–32. doi: 10.1016/j.echo.2016.11.016. [DOI] [PubMed] [Google Scholar]
  • 56.Gokhroo RK, Anantharaj A, Bisht D, Kishor K, Plakkal N, Aghoram R, et al. A pediatric echocardiographic Z-score nomogram for a developing country: Indian pediatric echocardiography study –The Z-score. Ann Pediatr Cardiol. 2017;10:31–8. doi: 10.4103/0974-2069.197053. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 57.Lopez L, Colan S, Stylianou M, Granger S, Trachtenberg F, Frommelt P, et al. Relationship of echocardiographic Z scores adjusted for body surface area to age, sex, race, and ethnicity: The pediatric heart network normal echocardiogram database. Circ Cardiovasc Imaging. 2017;10:e006979. doi: 10.1161/CIRCIMAGING.117.006979. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 58.Majonga ED, Rehman AM, McHugh G, Mujuru HA, Nathoo K, Patel MS, et al. Echocardiographic reference ranges in older children and adolescents in sub-Saharan Africa. Int J Cardiol. 2017;248:409–13. doi: 10.1016/j.ijcard.2017.06.109. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 59.Rajagopal H, Uppu SC, Weigand J, Lee S, Karnik R, Ko H, et al. Validation of right atrial area as a measure of right atrial size and normal values of in healthy pediatric population by two-dimensional echocardiography. Pediatr Cardiol. 2018;39:892–901. doi: 10.1007/s00246-018-1838-3. [DOI] [PubMed] [Google Scholar]
  • 60.Choudhry S, Salter A, Cunningham TW, Levy PT, Nguyen HH, Wallendorf M, et al. Normative left ventricular m-mode echocardiographic values in preterm infants up to 2 kg. J Am Soc Echocardiogr. 2017;30:781–9.e4. doi: 10.1016/j.echo.2017.04.010. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 61.van Ark AE, Molenschot MC, Wesseling MH, de Vries WB, Strengers JL, Adams A, et al. Cardiac valve annulus diameters in extremely preterm infants: A cross-sectional echocardiographic study. Neonatology. 2018;114:198–204. doi: 10.1159/000488387. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 62.Krysztofiak H, Młyńczak M, Małek ŁA, Folga A, Braksator W. Left ventricular mass normalization for body size in children based on an allometrically adjusted ratio is as accurate as normalization based on the centile curves method. PLoS One. 2019;14:e0225287. doi: 10.1371/journal.pone.0225287. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 63.Abushaban L, Rathinasamy J, Sharma PN, Vel MT. Normal reference ranges for the left ventricular mass and left ventricular mass index in preterm infants. Ann Pediatr Cardiol. 2020;13:25–30. doi: 10.4103/apc.APC_171_18. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 64.Trivedi B, Chokhandre M, Dhobe P, Garekar S. Estimation of Zscores of cardiac structures in healthy Indian pediatric population. J Indian Acad Echocardiogr Cardiovasc Imaging. 2018;2:147–54. [Google Scholar]

Articles from Annals of Pediatric Cardiology are provided here courtesy of Wolters Kluwer -- Medknow Publications

RESOURCES