The Relation Between QT Interval, QT Dispersion, Corrected QT Interval, Corrected QT Dispersion and Cardiovascular Risk Variables in Normotensive Obese Children

Abstract

The goal of this search was to find out whether the sensitivity of QT interval, QT dispersion (QTd), corrected QT (QTc) interval and corrected QT dispersion (QTcd) sensitivity in the early diagnosis of ventricular arrhythmia and cardiovascular mortality in normotensive exists or not and to evaluate their relation to the parameters examined in terms of cardiovascular complications, such as body mass index (BMI) and finally if there is a significant relationship in between, to draw attention to the risk of serious ventricular arrhythmia in this group of children. 

Method: 30 obese children who were followed up with exogenous obesity at the Department of Pediatric Endocrinology and 20 healthy children who came to the Pediatric Cardiology Polyclinic with the preliminary diagnosis of innocent murmur were included in the study. Fasting serum lipids, glucose and insulin levels were examined in all children through anthropometric and blood pressure measurements. Electrocardiographic recordings were obtained and QT interval, QT dispersion, QTc interval and QTc dispersion were calculated. The apical widths in the apical four cavity positions were evaluated with two-dimensional and m-mode echocardiography.

Results: QT interval, QT dispersion (QTd), corrected QT (QTc) interval and corrected QT dispersion (QTcd) obtained from ECG recordings in the early diagnosis of ventricular arrhythmia and cardiovascular mortality were higher in the patient group, but no statistically meaningful difference was found when compared to the control group. There was no positive correlation between these values related to QT interval and blood lipids and serum insulin levels which were examined in terms of body mass index and cardiovascular complications. However, increased left ventricular mass, body mass index, left ventricular mass index and m-mode echocardiographic measurements showed positive correlation as expected. 

Conclusion: There is no risk of severe ventricular arrhythmia in normotensive children diagnosed with exogenous obesity as it is in adults. However, this group of children should be closely monitored for serious rhythm disorders that will occur later in life and care should be taken for potential complications. 

Keywords

• Obezite
• QT dispersiyonu
• ekokardiyografi
• kardiyovasküler risk faktörleri
• çocuklar

References

1. Ng M, Fleming T, Robinson M, et al. Global, regional, and national prevalence of overweight and obesity in children and adults during 1980-2013: a systematic analysis for the Global Burden of Disease Study 2013. Lancet. 2014;384(9945):766-781.
2. 2. Derman O KN, Akgul S. . Ergenlerde obezite ve komplikasyonları Ergen sağlığı 2012:84-87.
3. 3. Di Salvo G, Pacileo G, Del Giudice EM, et al. Abnormal myocardial deformation properties in obese, non-hypertensive children: an ambulatory blood pressure monitoring, standard echocardiographic, and strain rate imaging study. Eur Heart J. 2006;27(22):2689-2695.
4. 4. Parlak A CS. Çocuklarda obezitenin oluşumunu etkileyen faktörler. Fırat Sağlık Hizmetleri Dergisi. 2007;5:24-35.
5. 5. Baskan M KG, Gurses D. Çocuklarda obezite ile ventrikül repolarizasyonu arasındaki ilişki. Türk Kardiyol Dern Arş. 2001;29:47-52.
6. 6. Seyfeli E AF, Yalcın F. . Obezite ve kardiyak aritmiler. . Türk Aritmi, Pacemaker ve Elektrofizyoloji Dergisi 2008;1:14-19.
7. 7. Caglı K EK, Lafcı G, Gedik HS, Ulas MM. . QT and P wave dispersion. Journal of Ankara University Faculty of Medicine. 2005;58:42-46.
8. 8. de Bruyne MC, Hoes AW, Kors JA, Hofman A, van Bemmel JH, Grobbee DE. QTc dispersion predicts cardiac mortality in the elderly: the Rotterdam Study. Circulation. 1998;97(5):467-472.

9. 9. Okin PM, Devereux RB, Howard BV, Fabsitz RR, Lee ET, Welty TK. Assessment of QT interval and QT dispersion for prediction of all-cause and cardiovascular mortality in American Indians: The Strong Heart Study. Circulation. 2000;101(1):61-66.
10. 10. National Cholesterol Education Program (NCEP): highlights of the report of the Expert Panel on Blood Cholesterol Levels in Children and Adolescents. Pediatrics. 1992;89(3):495-501.
11. 11. WA. N. Nelson Textbook Disorders of lipoprotein metabolism and transport. 19th ed. New York: Elsevier Science; 2011.
12. 12. Alikasifoglu A YN. Obezitenin tanımı ve prevelansı. Katkı Pediatri Dergisi. 2000;21:475-481.
13. 13. MA S. Obesity. In: Pediatric endocrinology. Philadelphia:701-716.
14. 14. ÖA. Ö. Sistolik Fonksiyonların Değerlendirilmesi ve Kardiyak Boşlukların Ölçülmesi. In: Oh JK SJ, Tajik AJ, ed. The Echo Manual.2009:109-119.
15. 15. de Simone G, Daniels SR, Devereux RB, et al. Left ventricular mass and body size in normotensive children and adults: assessment of allometric relations and impact of overweight. J Am Coll Cardiol. 1992;20(5):1251-1260.
16. 16. GS W. Marriott's practical electrocardiography. 10th edition ed. Philadelphia: Lippincott Williams&Wilkins; 2001.
17. 17. HC B. An analysis of the time relations of electrocardiograms. Annals of Noninvasive Electrocardiology. 1997;2:177-194.
18. 18. Speiser PW, Rudolf MC, Anhalt H, et al. Childhood obesity. J Clin Endocrinol Metab. 2005;90(3):1871-1887.
19. 19. Hacihamdioğlu B OV, Yozgat Y, Yildirim D, Kocaoğlu M, Lenk MK, Özcan O. Abdominal obesity is an independent risk factor for increased carotid intima- media thickness in obese children. Turk J Pediatr 2011;53(1):48-54.
20. 20. Kelley RE, Dasmahapatra P, Wang J, et al. Prevalence of atherosclerotic plaque in young and middle-aged asymptomatic individuals: the Bogalusa heart study. South Med J. 2011;104(12):803-808.
21. 21. Sasson Z, Rasooly Y, Bhesania T, Rasooly I. Insulin resistance is an important determinant of left ventricular mass in the obese. Circulation. 1993;88(4 Pt 1):1431-1436.
22. 22. Poirier P, Giles TD, Bray GA, et al. Obesity and cardiovascular disease: pathophysiology, evaluation, and effect of weight loss. Arterioscler Thromb Vasc Biol. 2006;26(5):968-976.
23. 23. Dai S, Harrist RB, Rosenthal GL, Labarthe DR. Effects of body size and body fatness on left ventricular mass in children and adolescents: Project HeartBeat! Am J Prev Med. 2009;37(1 Suppl):S97-104.
24. 24. Di Bonito P, Capaldo B, Forziato C, et al. Central adiposity and left ventricular mass in obese children. Nutr Metab Cardiovasc Dis. 2008;18(9):613-617.
25. 25. Aknc A, Karakurt C, Gurbuz S, et al. Association of cardiac changes with serum adiponectin and resistin levels in obese and overweight children. J Cardiovasc Med (Hagerstown). 2013;14(3):228-234.
26. 26. Crowley DI, Khoury PR, Urbina EM, Ippisch HM, Kimball TR. Cardiovascular impact of the pediatric obesity epidemic: higher left ventricular mass is related to higher body mass index. J Pediatr. 2011;158(5):709-714.e701.
27. 27. Li X, Li S, Ulusoy E, Chen W, Srinivasan SR, Berenson GS. Childhood adiposity as a predictor of cardiac mass in adulthood: the Bogalusa Heart Study. Circulation. 2004;110(22):3488-3492.
28. 28. Wong CY, O'Moore-Sullivan T, Leano R, Byrne N, Beller E, Marwick TH. Alterations of left ventricular myocardial characteristics associated with obesity. Circulation. 2004;110(19):3081-3087.
29. 29. de Simone G, Devereux RB, Kizer JR, et al. Body composition and fat distribution influence systemic hemodynamics in the absence of obesity: the HyperGEN Study. Am J Clin Nutr. 2005;81(4):757-761.
30. 30. Iacobellis G, Ribaudo MC, Leto G, et al. Influence of excess fat on cardiac morphology and function: study in uncomplicated obesity. Obes Res. 2002;10(8):767-773.
31. 31. Kibar AE PF, Oflaz MB, Ballı Ş, Ece İ. . Normotansif obez çocuklarda sol ventrikül fonksiyonunun ekokardiyografi ile değerlendirilmesi: Beden kütle indeksine göre karşılaştırmalı analiz. Türk Kardiyol Dern Arş. 2012;40(4):337-346.
32. 32. Mehta SK, Richards N, Lorber R, Rosenthal GL. Abdominal obesity, waist circumference, body mass index, and echocardiographic measures in children and adolescents. Congenit Heart Dis. 2009;4(5):338-347.
33. 33. Atabek ME, Akyuz E, Selver Eklioglu B, Cimen D. The relationship between metabolic syndrome and left ventricular mass index in obese children. J Clin Res Pediatr Endocrinol. 2011;3(3):132-138.
34. 34. Kotsis V, Stabouli S, Papakatsika S, Rizos Z, Parati G. Mechanisms of obesity-induced hypertension. Hypertens Res. 2010;33(5):386-393.
35. 35. Huang PL. eNOS, metabolic syndrome and cardiovascular disease. Trends Endocrinol Metab. 2009;20(6):295-302.
36. 36. Baba R, Koketsu M, Nagashima M, Inasaka H, Yoshinaga M, Yokota M. Adolescent obesity adversely affects blood pressure and resting heart rate. Circ J. 2007;71(5):722-726.
37. 37. Alpert MA, Terry BE, Cohen MV, Fan TM, Painter JA, Massey CV. The electrocardiogram in morbid obesity. Am J Cardiol. 2000;85(7):908-910, a910.
38. 38. Nigro G, Russo V, Di Salvo G, et al. Increased heterogenity of ventricular repolarization in obese nonhypertensive children. Pacing Clin Electrophysiol. 2010;33(12):1533-1539.
39. 39. Oliveira AMAd. Epidemiological and Clinical Aspects in a Developing Country. In: Yuca SA, ed. Childhood Obesity.2012:3-14.
40. 40. Bray GA. Risks of obesity. Endocrinol Metab Clin North Am. 2003;32(4):787-804, viii.
41. 41. Z Ş. Çocuk ve Adolesanlarda Obezite Komplikasyonları ve Metabolik Sendrom. Turkish J Pediatr Dis 2012;1(2):48-56.
42. 42. Karagoz T DA. Sekonder Hiperlipidemiler. Katkı Pediatri Dergisi. 1998 19(4-5):493- 505.
43. 43. Rizk NM, Yousef M. Association of lipid profile and waist circumference as cardiovascular risk factors for overweight and obesity among school children in Qatar. Diabetes Metab Syndr Obes. 2012;5:425-432.
44. 44. Fang J, Zhang JP, Luo CX, Yu XM, Lv LQ. Carotid Intima-media thickness in childhood and adolescent obesity relations to abdominal obesity, high triglyceride level and insulin resistance. Int J Med Sci. 2010;7(5):278-283.
45. 45. Abaci A, Tascilar ME, Saritas T, et al. Threshold value of subepicardial adipose tissue to detect insulin resistance in obese children. Int J Obes (Lond). 2009;33(4):440-446.
46. 46. Kannel WB, Plehn JF, Cupples LA. Cardiac failure and sudden death in the Framingham Study. Am Heart J. 1988;115(4):869-875.
47. 47. Amad KH, Brennan JC, Alexander JK. The cardiac pathology of chronic exogenous obesity. Circulation. 1965;32(5):740-745.
48. 48. Schouten EG, Dekker JM, Meppelink P, Kok FJ, Vandenbroucke JP, Pool J. QT interval prolongation predicts cardiovascular mortality in an apparently healthy population. Circulation. 1991;84(4):1516-1523.
49. 49. el-Gamal A, Gallagher D, Nawras A, et al. Effects of obesity on QT, RR, and QTc intervals. Am J Cardiol. 1995;75(14):956-959.
50. 50. Seyfeli E, Duru M, Kuvandik G, Kaya H, Yalcin F. Effect of obesity on P-wave dispersion and QT dispersion in women. Int J Obes (Lond). 2006;30(6):957-961.
51. 51. Lee S, Cowan PA, Wetzel GT, Velasquez-Mieyer P. Prediabetes and blood pressure effects on heart rate variability, QT-interval duration, and left ventricular hypertrophy in overweight-obese adolescents. J Pediatr Nurs. 2011;26(5):416-427.
52. 52. Fukushige T, Yoshinaga M, Shimago A, et al. Effect of age and overweight on the QT interval and the prevalence of long QT syndrome in children. Am J Cardiol. 2002;89(4):395-398.
53. 53. Mukerji R, Petruc M, Fresen JL, Terry BE, Govindarajan G, Alpert MA. Effect of weight loss after bariatric surgery on left ventricular mass and ventricular repolarization in normotensive morbidly obese patients. Am J Cardiol. 2012;110(3):415-419.