Tissue doppler echocardiography for evaluating left ventricular functions in obese children

Öz

Objective: The aim of this study was to investigate the impact of childhood obesity on ventricular functions using tissue Doppler echocardiography. Materials and methods: The mitral tissue Doppler signals were recorded in the apical four-chamber view, with the sample volume placed at the lateral walls of mitral annu­lus. The mitral flow was examined with the sample Pulse Doppler positioned parallely to flow just at the orifice of the mitral leaflets. Twenty obese (161.50±25.78 months) and 20 healthy children (151.15±33.48 months) were included to this study. Results: Body mass index (BMI) was significantly higher in obese group (30.92±6.87). Isovolumic relaxation time (IVRT) which is one of the left ventricular (LV) diastolic function parameters was 66.10±7.30 ms in obese group, and 58.70±9.06 ms in the control group. IVRT was sig­nificantly higher in the obese group (p=0.007). In obese group, the mitral annulus tissue Doppler E velocity was decreased, flow velocity was increased and decrement in Em/Am ratio was significant. We found significant negative correlation between BMI and LV Em/Am ratio. Myocardial performance index (MPI) in obese group and control group was 0.50±0.07 and 0.41±0.04, respectively (p=0.000). Between MPI and LV Em/Am ratio there was a significant negative correlation while MPI showed positive correlation with BMI. In obese group septal and LV posterior wall thick­ness was shown to be significantly increased compared to the control group (p=0.000). Conclusion: Our findings, may be important for determina­tion of the relationship between obesity and cardiovascular risk factors in children. Tissue Doppler echocardiographic imaging may be useful in revealing this relationship.

Anahtar Kelimeler

• obesity, doppler echocardiography, ventricular dysfunction

Obez çocuklarda sol ventrikül fonksiyonlarının değerlendirilmesinde doku doppler ekokardiyografi

Öz

Amaç: Bu çalışmada obez çocuklarda transtorasik doku Doppler ekokardiyografik yöntemle sol ventrikül sistolik ve diyastolik fonksiyonlarının değerlendirilmesi amaçlandı. Gereç ve yöntem: Mitral doku Doppler sinyalleri, mitral annulus lateral duvarlarına yerleştirilen örnek hacmi ile apikal dört boşluktan kaydedildi. Pulse Doppler örneği apikal dört boşluk görüntüde mitral kapak uçlarına, akıma paralel olacak şekilde yerleştirilerek mitral akım trasesi elde edildi. Çalışmaya 20 obez (161,50±25.78 ay) ve 20 (151,15±33.48 ay) sağlıklı çocuk alınarak gerçekleştirildi. Bulgular: Vücut kitle indeksi (VKİ) obez grupta belirgin yüksekti (30,92±6,87). Sol ventrikül (LV) diyastolik fonk­siyon parametrelerinden izovolemik relaksasyon zamanı (IVRT) obez grupta 66,10±7,30 msn, kontrol grubunda ise 58,70±9,06 msn ile obez grupta anlamlı artış saptandı (p=0,007). Obez grubunda mitral anulus doku Doppler E akım hızı azalmış, A akım hızı artmış ve Em/Am oranının anlamlı derecede azalmış olduğu görüldü. VKİ ile LV Em/ Am oranı arasında anlamlı negatif ilişki saptandı. Miyo­kardiyal performans indeksi (MPİ) obez grupta 0,50±0,07, kontrol grubunda ise 0,41±0,04 (p=0.000) bulundu. MPİ ile LV Em/Am oranı arasında anlamlı negatif ilişki sap­tandı. MPİ ile VKİ arasında anlamlı pozitif ilişki saptandı. Obez grupta kontrol grubuna göre interventriküler septum ve LV arka duvar kalınlığının önemli derecede artmış ol­duğu gösterildi. Sonuç: Bu bulgular, pediatrik yaş grubunda obezite ve kardiyovasküler risk faktörleri arasındaki ilişkiyi belirle­mek için önemli bulgular olabilir. Doku Doppler ekokardi­yografik görüntüleme yöntemi ise aralarındaki bu ilişkinin belirlenmesinde yararlı olabilir.

Anahtar Kelimeler

• Obezite, doppler ekokardiyografi, ventriküler disfonksiyon

Kaynakça

1. Schonfeld-Warden N, Warden CH. Pediatric obesity. An over- view of etiology and treatment. Pediatr Clin North Am 1997;44:339-61.
2. Yerlikaya HF, Mehmetoğlu İ. Investigation of plasma conjugated linoleic acid levelsin obese and healthy subjects. J Clin Annal Med 2012;3:190-3.
3. Cinaz P, Bideci A. [Obesity]. In: Günöz H, Öcal G, Yordam N, Kurtoğlu S.(eds). Pediatrik endokrinoloji. 1.Basım. Pediatrik Endokrinoloji ve Oksoloji Derneği Yayınları 1;2003.p.487-505.
4. Rössner S. Childhood obesity and adulthood consequences. Acta Pediatrica 1998;87:1-5
5. Sutherland GR, Stewart MJ, Groundstroem KWE, et al. Color Doppler myocardial imaging: a new technique for assessment of myocardial function. J Am Soc Echocardiogr 1994;7:441- 58.
6. Mehta SK, Holliday C, Hayduk L, Wiersma L, Richards N, You- noszai A. Comparison of myocardial function in children with body mass indexes > 25 versus those < 25 kg/m. Am J Cardiol 2004;293:1567-9.
7. Van Putte-Katier N, Rooman RP, Haas L, et al. Early cardiac abnormalities in obese children: importance of obesity per se versus associated cardiovascular risk factors. Pediatr Res 2008;64:205-9.
8. Freedman DS, Srinivasan SR, Harsha DW, Webber LS, Beren- son GS. Relation of body fat patterning to lipid and lipoprotein concentrations in children and adolescents: the Bogalusa Heart Study. AM J Clin Nutr 1989;50:930-9.

9. Freedman DS, Dietz WH, Srinivasan SR, Berenson GS. The relation of overweight to cardiovascular risk factors among children and adolescents: Bogalusa Heart Study. Pediatrics 1999;103:1175-82.
10. Daniels S. Morrison J, Sprecher DL, Khoury P, Kimball TR. Association of body fat distribution and cardiovascular risk fac- tors in children and adolescents. Circulation 1999; 99:541-5.
11. Isaaz K, Thompson A, Ethevenot G, Cloez JL, Brembilla B, Per- not C. Doppler echocardiographic measurement of low veloc- ity motion of the left ventricular posterior wall. Am J Cardiol 1989;64:66-75.
12. McCarthy HD, Jarrett KV, Crawley HF. Original communica- tion the development of wrist circumference percentiles in Brit- ish children aged 5.0-16.9 y. Eur J Clin Nutr 2001;55:902-7.
13. Dagdelen S, Eren N, Karabulut H, et al. Estimation of left ven- tricular end-diastolic pressure by color M-mode doppler echo- cardiography and tissue doppler imaging. J Am Soc Echocar- diogr. 2001;14:951-8.
14. Yazıcı HU, Şen N, Tavil Y, et al. Left ventricular functions in patients with cardiac syndrome X: a tissue Doppler study. An- adolu Kardiyol Derg 2009;9:467-72.
15. Kapusta L, Thijssen JM, Cuypers NHN, Peer PGM, Daniels O. Assessment of myocardial velocities in healthy children using tissue Doppler imaging. Ultrasound Med Biol 2000;26:229-37.
16. Çaylı M, Usal A, Kanadaşı M, Demir M, Akpınar O. Assess- ment of Left ventricular diastolic dysfunctions with a new method: Tissue Doppler echocardiography. Türk Kardiyol Dern Arş 2004;32:618-25.
17. Oğuzhan A, Abacı A, Eryol NK, et al. Doppler Tissue Imaging: A noninvasive technique for estimation of left ventricular end- diastolic pressure. Arch Turk Soc Cardiol 2000;28:82-7.
18. Harada K, Orino T, Takada G. Body mass index can predict left ventricular diastolic filling in asymptomatic obese children. Pediatr Cardiol 2001;22:273-8.
19. Tei C. New non-invasive index for combined systolic and dia- stolic ventricular function. J Cardiol. 1995;26:135-6.
20. Abstract 1472: Obesity-related left ventricular functional change starts in early childhood Kenji Harada. Harada Kid’s Clinic, Akita, Japan. Turk J Pediatr 2005;47:34-8.
21. Levent E, Gökşen D, Ozyürek AR, Darcan S, Coker M. Useful- ness of the myocardial performance index (MPI) for assessing ventricular function in obese pediatric patients. Turk J Pediatr 2005;47:34-8.
22. Sasson Z, Rasooly Y, Bhesania T, Rasooly I. Insulin resistance is an important determinant of left ventricular mass in obese. Circulation 1993;88:1431-6.
23. Wong CY, O’Moore-Sullivan T, Leano R, Byrne N, Beller E, Marwick TH. Alterations of left ventricular myocardial charac- teristics associated with obesity. Circulation 2004;110:3081-7.
24. Ehud G, Oren S, Messerli FH. Left ventricular filling in the systemic hypertension of obesity. Am J Cardiol 1991;68:57-60.
25. Berkalp B, Cesur V, Corapcioglu D, Erol C, Baskal N. Obe- sity and left ventricular diastolic dysfunction. Int J Cardiol. 1995;10:52:23-6.
26. Di Salvo, Pacileo G, Del Giudice EM, et al. Abnormal myocar- dial deformation properties in obese, nonhypertensive children: an ambulatory blood pressure monitoring, Standard echocar- diographic, and strain rate imaging study. Eur Heart Journal 2006;27:2689-95.