11
Članek prispel / Received
8. 6. 2018
Članek sprejet / Accepted
9. 6. 2021
Abstract
Purpose: To assess the myocardial 
strain in children with hypertrophic car-
diomyopathy (HCM).
Methods: A total of 61 patients aged 
between 7 and 17 years with an asym-
metric form of HCM underwent an ul-
trasound examination of the heart using 
standard techniques. An assessment 
of the left ventricular systolic function 
was performed using the two-dimensi-
onal (2D) speckle-tracking mode with 
analysis parameters that included global 
and segmental longitudinal, circumfe-
rential, and radial myocardial strains. 
Strain data for the subendocardial and 
subepicardial layers for each segment of 
the left ventricle, as well as their total 
values, were determined.
Results: Global longitudinal strain 
and longitudinal strain rate were dec-
Izvleček
Namen: Ocena deformacije (strain) 
miokarda pri otrocih s hipertrofično kar-
diomiopatijo (HKMP). 
Metode: 61 otrokom starosti med 7 in 
17 let z asimetrično obliko smo z 2D 
sledenjem ultrazvočnega vzorca (2D 
speckle-tracking imarging) deformacije 
miokarda ocenili sistolično funkcijo le-
vega ventrikla. V analizi smo uporabili 
globalno in segmentno longitudinalno, 
cirkumferenčno in radialno deformaci-
jo. Pridobili smo podatke o deformaciji 
slojev endokarda in epikarda, glede na 
določen segment levega ventrikla, kot 
tudi skupne vrednosti deformacije.
Rezultati: PGlobalna longitudinalna 
deformacija in longitudinalna stopnja 
deformacije sta se zmanjšali zaradi mo-
tenega krčenja hipertrofiranih segmen-
tov v 100% primerov neobstruktivnih 
Ključne besede: 
2D sledenje ultrazvočnega 
vzorca, deformacija miokarda, 
ehokardiografija, hipertrofična 
kardiomiopatija, zgodnja diagnoza, 
zdravljenje, otrok.
Key words: 
2D speckle tracking, strain, 
echocardiography, hypertrophic 
cardiomyopathy, early diagnosis, 
treatment, children.
2D sledenje ultrazvočnega vzorca deformacije 
miokarda pri otrocih s hipertrofično kardiomiopatijo
2D speckle-tracking in assessment of myocardial 
strain in children with hypertrophic cardiomyopathy
Avtor / Author Nadezhda Chernykh1, Alla Tarasova2, Olga Groznova3
Ustanova / Institute 1Univerza v Mariboru, Medicinska fakulteta, Maribor, Slovenija; 2Russian Medical Academy 
Continuous Professional Education Ministry of Health of the Russian Federation, Moscow, 
Russia; 3Academician Yu. E. Veltishchev Research Clinical Institute of Pediatrics, N. I. 
Pirogov Russian National Research Medical University, Ministry of Health of the Russian 
Federation, Moscow, Russia;
1University Medical Centre Maribor, Division of Pediatrics, Department for General Pediatrics, 
Maribor, Slovenia; 2 Russian Medical Academy Continuous Professional Education Ministry 
of Health of the Russian Federation, Moscow, Russia; 3Academician Yu. E. Veltishchev 
Research Clinical Institute of Pediatrics, N. I. Pirogov Russian National Research Medical 
University, Ministry of Health of the Russian Federation, Moscow, Russia;
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INTRODUCTION
Two-dimensional (2D) speckle-tracking is a noninvasive 
ultrasonic method of heart visualization that allows to 
evaluate the kinetics of the myocardium. This method 
is based on the ultrasound tracking of the "spot" or 
speckle in the myocardial tissue, which results in the 
formation of a spectral pattern. Speckle is unique for 
each part of the myocardium. It reflects the movement 
of myocardial tissue. The operating system follows 
the speckle in the 2D plane, defining its movement 
trajectory or tracking. Then, myocardial segments are 
isolated and their kinetics assessed. The displacement of 
the myocardium or strain is the main parameter in this 
method. Using 2D speckle-tracking, it becomes possible 
to define the longitudinal, radial, and circumferential 
myocardial strains and to estimate their rates (1, 2). 
This method has several advantages. First, it does not 
depend on the scanning angle in a way that tissue 
Doppler examination does. Second, any parameters 
can be calculated and analyzed in different parts of the 
myocardium in the off-line mode. It is also necessary to 
take into account the limitations of this method. The 
optimal frame rate should be 60–100 frames/min. It 
also depends on the heart and respiratory rates (3, 4). 
In addition, the operating system does not perform an 
integral analysis of strain in tachycardia and tachypnea 
(5). Finally, it is difficult to assess strain due to many 
in obstruktivnih oblik HKMP. Zmanj-
šanje parametrov globalne, radialne 
in cirkularne deformacije smo opazili 
pri vseh bolnikih z obstruktivno obliko 
HKMP in pri 39 (86,6%) bolnikih z 
neobstruktivno obliko bolezni. Obenem 
smo ugotovili statistično pomembno 
razliko med deformacijo in stopnjo de-
formacije pri bolnikih z neobstruktivno 
obliko bolezni v primerjavi z obstruktiv-
no obliko HKMP.
Zaklju~ek: Spremembe deformacije 
miokarda pri otrocih s HKMP z 2D 
sledenjem ultrazvočnega vzorca naka-
zujejo zgodnjo sistolično disfunkcijo 
levega ventrikla. Longitudinalna defor-
macija miokarda se je v primerjavi z 
radialno in cirkumferenčnno, izkazala 
za najbolj občutljivi parameter. Ta kaže 
statistično pomembno razliko pri otrocih 
z obstruktivno obliko HKMP v primer-
javi z bolniki z neobstruktivno obliko 
bolezni. Izsledki, pridobljeni v tej razis-
kavi, so pomembni v okviru t.i. terapije 
zgodnjega začetka HKMP in so la-
hko pomembni pri izboljšanju prognoze 
otrok s HKMP.
reased due to the impaired contractility 
of hypertrophied myocardial segments in 
100% of cases of non-obstructive and 
obstructive HCM forms. A decrease in 
global, radial, and circumferential strain 
parameters and their rates has been ob-
served in all children with an obstructive 
form of HCM and 39 (86.6%) patients 
with non-obstructive form. At the same 
time, there was a statistically significant 
difference between strains and strain 
rates in children with a non-obstructive 
form of HCM in comparison to those 
with an obstructive form of the disease.
Conclusion: Changes in myocardial 
strains observed using the 2D speckle-
-tracking mode in children with HCM 
indicate early systolic dysfunction of the 
left ventricle. Longitudinal strain was the 
most sensitive compared to radial and 
circumferential types. It was statistically 
significantly different in children with an 
obstructive form of HCM compared to 
those with non-obstructive form of the di-
sease. These results are important for early 
therapy initiation and, therefore, may im-
prove prognosis in children with HCM.
Naslov za dopisovanje /  
Correspondence
Nadezhda Chernykh, Erazmus študentka 
na MF UM
Telefon +7(917) 3317861
E-pošta: chernykh-nauka@mail.ru
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artifacts in the extracted image when performed on 
a non-compact myocardium (6). It is necessary to 
consider different accuracy levels when assessing data 
in the longitudinal and cross directions. 
The 2D speckle tracking allows to assess the local systolic 
function of the myocardium (5,7). The method has 
found wide application in the adult cohort of patients 
in assessing the local contractility of the ischemic site 
after a previous myocardial infarction (8). In addition, 
many publications on the use of 2D speckle-tracking 
in oncology and nephrology are devoted to evaluating 
the local myocardial contractility in patients taking 
cardiotoxic drugs (9,10).
The use of a 2D speckle-tracking method is limited in 
children due to their high heart and respiration rates. 
The global longitudinal strain of the myocardium is well 
studied. Radial and circular strains have been studied 
much less due to the small myocardial wall thickness 
(on average up to 6 mm) and a large number of artifacts 
(11). The 2D speckle-tracking method is very important 
for children with hypertrophic cardiomyopathy (HCM) 
(12). HCM is the second most common disease of the 
myocardium in children. Most commonly, it is identified 
by an asymmetrical interventricular septum with a 
predominant lesion. For these children, the assessment 
of local left ventricular systolic function is critical (13). 
However, the values of global systolic function (ejection 
and shortening fractions) lie within the relevant 
values over a long period of time (14). Assessment of 
myocardial strain changes is a promising and topical 
direction in the definition of early disruptions of local 
contractility in the left ventricular myocardium. This 
technique helps to define observation tactics and to 
correct the treatment strategy for children with HCM.
The purpose of the study: to assess myocardial strain in 
children with HCM. 
MATERIALS AND METHODS 
A total of 61 patients (14 girls, 47 boys, age range: 
7–17 years, mean age: 12 years) with an asymmetric 
form of HCM underwent a comprehensive clinical, 
laboratory, and instrumental examination and received 
treatment in the cardio-rheumatology department of 
the Academician Yu. E. Veltishchev Research Clinical 
Institute of Pediatrics in 2014–2018 in Moscow, Russia. 
A total of 45 (73.8%) children had the non-obstructive 
form of HCM, and 16 (26.2%) children had the 
obstructive form of HCM. Obstruction was determined 
at the level of the left ventricular output tract. The 
pressure gradient was 30–50 mm Hg both at rest and 
during the stress test. Latent forms of obstruction were 
not revealed. A total of 21 (34.4%) children had their 
disease diagnosed before the age of seven. In addition, 
there were 34 (55.7%) children who were diagnosed 
at age 7–12 years and only six (9.9%) at 13–17 years. 
The disease exposure at the time of examination was ≤1 
year for six (9.9%) children, 1–5 years for 40 (65.6%) 
children, and >5 years for 15 (24.5%) children. 
The ultrasound heart examination was carried out 
in accordance with the standard technique on a 
Toshiba Artida ultrasound machine (Japan) using 
a matrix sensor with a frequency range of 4–6 MHz. 
Parameter assessment of the global left ventricular 
systolic function was performed in 2D mode to obtain 
an ejection fraction (EF, %) measured using  the 
Simpson’s method and a shortening fraction (FS, %) 
(15). Local systolic function assessment was performed 
in off-line 2D speckle-tracking mode. Global and 
segmental longitudinal, circumferential, and radial 
myocardial strain and strain rate in 12 segments of the 
basal and median left ventricular departments were 
measured. The software provided the strains for the 
subendocardial and subepicardial myocardial layers in 
each segment and their total values.
Apical positions (two- and four-chamber) on the 
long axis of the left ventricle were used to measure 
the longitudinal strain. To assess the radial and 
circumferential strains, parasternal positions along the 
short axis of the left ventricle at the mitral valve level 
and the papillary muscles were used (Fig. 1). In addition, 
the electrocardiogram was recorded in parallel. All 
children’s heart and respiratory rates were within the 
relevant values. The software carried out the analysis of 
integral myocardial strain curves at the time of systole 
COR in the automatic and semi-automatic modes from 
the R wave on an electrocardiogram during three cardiac 
cycles and obtained the average values. To compare 
the myocardial wall thickness and strain parameters 
in 2D mode, the thickness was measured in the same 
segments where the myocardial strain assessment was 
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carried out. A 16-segment left ventricular division was 
used to assess the local myocardial contractility (4).
Statistical analysis of the results was carried out using 
STATISTICA 10.0 software (StatSoft, Tulsa, OK, 
USA). The quantitative data provided the mean 
(M), standard deviation (σ), median, minimum, and 
maximum values. The Kruskal–Wallis (ANOVA) tests 
were performed to assess the significance of differences 
in quantitative variables in the small groups. The χ² 
criteria were used for the assessment of reliability of 
qualitative variable differences.  
Studies were conducted in accordance with ethical 
principles and legislation. All of the children and their 
parents signed the informed consent form to participate 
in the study.
RESULTS 
The EF and FS of the left ventricle were lower than 
the relevant values in five (11.1%) children with the 
Figure 1. Measurement of left ventricular radial strain in 2D speckle tracking mode. Parasternal 
position along the short axis of the left ventricle in the papillary muscle level of the mitral valve.
non-obstructive form of HCM and in all patients with 
obstructive form of HCM (р=0.0001). Five children 
with the non-obstructive HCM and decreased EF and 
FS had a noticeable degree of hypertrophy in three 
myocardial segments of the left ventricle (myocardial 
thickness: ≥25 mm; z-score: >4.24; Fig. 1).
Global longitudinal strain and longitudinal strain rate 
decreased in both groups in 100% of cases. A decrease 
in global, radial, and circumferential strain parameters 
and their rates was observed in every child with an 
obstructive form of HCM and in 39 (86.6%) children 
with a non-obstructive form. At the same time, there 
was a statistically significant difference in the strain rate 
parameters in children with a non-obstructive form of 
HCM compared to those with an obstructive form of 
the disease (Table 1).
A total of 40 (65.6%) children had mild hypertrophy 
of 2–3 myocardial segments of the left ventricle 
(myocardial thickness of up to 20 mm; z-score: ≤4.24). 
In addition, 21 (34.4%) children had expressed 
hypertrophy of 3–7 segments (myocardial thickness 
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>25 mm; z-score: >4.24). In the analysis of the degree of 
hypertrophy expression, the hypertrophy prevailed in 
the anteroseptal, anterior, and anterolateral segments, 
which corresponded to the topographical level of the 
interventricular septum (Fig. 2). The strain indicators in 
these segments were below the corresponding relevant 
values (20%). In addition, there was an increase in the 
strain indicators in the contralateral segments (Fig. 
3). When assessing the myocardial layer strain, higher 
strain indicator values in the subendocardial layer of 
the myocardium were observed compared to those in 
the subepicardial layer (Fig. 4). 
An analysis of the relationship between the strain 
indicators, EF, and FS showed that children with 
an obstructive form of HCM had "mean" feedback 
(statistically significant) between the longitudinal 
strain, EF, and FS. Direct correlations between radial 
and circular strain and EF and FS were noted. Similar 
correlation relationships were obtained when assessing 
the left myocardial ventricle (Table 2).
DISCUSSION
The study data confirmed the higher parameter 
sensitivity in the strain indicators used for the 
assessment of systolic function of the left ventricle 
compared to the EF and FS, which is in accordance 
with previously reported results (16). Changes in the 
Figure 2. Frequency of hypertrophied segments in 
children with HCM.
Figure 3. Mean values of strain parameters (lon-
gitudinal, radial, and circular) in each segment in 
children with HCM.
Table 1. Left ventricular parameters of systolic function in children with HCM (N=61) .
PARAMETERS 
(relevant values)
Non-obstructive form HCM (n=45) Obstructive form HCM (n=16) Reliability of 
distinctions,
 рМ±σ Median Min. - max. values. М±σ Median
Min. - max. 
values.
Longitudinal strain (20%) -11.06±6.4 -10.44* -9.33-18.4 -10.13±6.07 -8,24 -0.49-14.42 0.002
Longitudinal strain rate (0,68 s-1) -0.59±0.13 -0.61* -0.46-0.66 -0.36±0.23 -0.35 -0.22-0.61 0.0025
Radial strain (20%) 19.44±14.5 19.14* 8.44-39.6 15.10±11.2 13.42 0.89-18.1 0.003
Radial strain rate (1,08 s-1) 1.01±0.11 1.02* 0.82-2.77 0.94±0.41 0.87 0.65-1.02 0.002
Circular strain (20%) -17.25±13.4 -18.11* -8.9±33.5 -11.62±9.11 -12.29 -0.69±16.2 0.016
Circular strain rate   (0,74 s-1) -0.65±0.14 -0.56* -0.12±-1.4 -0.51±0.21 -0.48 -0.32-0.71 0.011
Fractional shortening         (30-
45%) 28.44±1.99 30* 26-36 25.4±2.89 22 20-26 0.003
Ejection Fraction (60-75%)) 62.14±2.34 66* 58-68 52.12±2.98 52 48-58 0.002
Note: * – reliability of distinctions at р≤0,05.
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segmental and global longitudinal myocardial strains 
begin early. Changes in the traditional EF and FS start 
much later (17). These findings have been confirmed 
in the present research. Parameters of global and 
segmental longitudinal strain and their rates were 
reduced in 100% of cases. However, more than half of 
the children had intact EF and FS.
The analysis showed a decreased strain in more 
hypertrophied segments and increased strain in 
contralateral segments for children with HCM. This 
Table 2. Coefficients of correlation (r) between left ventricular parameters of systolic function in children with HCM.
PARAMETERS
Non-obstructive form Obstructive form
EF FS EF FS
Longitudinal strain (%) r=-0,34 r=-0,34 r=0,50* r=-0,53*
Longitudinal strain rate (s-1) r=-0,39 r=-0,39 r=0,50* r=-0,51*
Radial strain (%) r=-0,31 r=-0,31 r=0,32* r=-0,34*
Radial strain rate (s-1)(s) r=-0,36 r=-0,36 r=0,39* r=-0,39*
Circular strain (%) r=-0,32 r=-0,32 r=0,42* r=-0,41*
Circular strain rate   (s-1) r=-0,34 r=-0,34 r=0,37* r=0,37*
Note: * – reliability of distinctions at р≤0,05. EF – Ejection Fraction; FS – Fraction shortening.
Figure 4. Mean values of segmental strain parameters (subendocardial and subepicardial layers) in left ventricu-
lar myocardium in children with HCM.
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reveals how the compensatory mechanisms of the 
myocardium act. It also explains why the disease is not 
clinically apparent for a long time until it is exposed 
during a routine screening. Strain is a dynamic indicator 
reflecting well-expressed compensatory mechanisms in 
children with HCM.
The higher values of the myocardial strain parameters in 
the subepicardial layer compared to the subendocardial 
layer have been confirmed by prior studies (4,18). In 
the subendocardial layers of healthy cohort patients, 
strain values were higher than those in the subepicardial 
layers. This is apparently connected to the mechanical 
properties of the heart. The myocardial movement 
during systole begins in the subendocardial layers and 
progressively terminates in the pericardium.
The latest European guidelines for the diagnosis and 
treatment of HCM (13) recommend using 2D speckle-
tracking to detect early signs of systolic dysfunction in 
this group of patients. The results of the present study 
have shown that the strain indicators obtained using 
2D speckle-tracking can be useful for planning further 
diagnostic studies and developing treatment tactics not 
only in adults with HCM, but also in children. The 
assessment of strain indicators is the most significant 
when evaluating the segmental systolic function of the 
heart in children with HCM.
CONCLUSION 
Changes in myocardial strain noticeable in the 2D speckle-
tracking mode in children with HCM indicate early 
disruptions in the systolic function of the left ventricle. 
Among them, the longitudinal strain was the most 
statistically significantly different compared to the radial 
and circumferential strains in children with an obstructive 
form of HCM compared to non-obstructive form of the 
disease. The obtained results are essential for initiating 
appropriate therapy and improving HCM prognosis in 
children.
CONFLICT OF INTEREST STATEMENT 
The authors declare that there are no conflicts of interest 
associated with this study.
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