Ghandi Yazdan, Ghahremani Bita, Habibi Danial, Pouya Afsane, Sadrnia Saiid
Amir Kabir Hospital, Arak University of Medical Sciences, Arak, Iran.
Department of Biostatistics and Epidemiology, Isfahan University of Medical Sciences, Isfahan, Iran.
J Tehran Heart Cent. 2020 Apr;15(2):64-68. doi: 10.18502/jthc.v15i2.4185.
Children with mitral valve prolapse (MVP) may be prone to ventricular arrhythmias due to transmural dispersion of repolarization (TDR). This study aimed to assess alterations in ventricular repolarization in children with MVP and to investigate their relationships with the degree of mitral regurgitation. Fifty children with MVP and 50 age- and sex-matched healthy children as controls were studied. Twelve-lead electrocardiography and echocardiography were performed in all the subjects. TDR parameters were QT and QTc intervals, QTc dispersion, Tp-e interval, Tp-e interval dispersion, Tp-e/QT, Tp-e/QTc, JTc, JTc dispersion, Tp-e/JT, and Tp-e/JTc. The mean age of the 50 patients with MVP was 12.45±2.50 years (F/M: 15/35). There were no significant differences in QT and QTc intervals between the 2 groups. QTc dispersion (P=0.001), Tp-e dispersion interval (P=0.002), Tp-e/QTc (P=0.001), JTc dispersion (P=0.023), Tp-e/JT (P=0.004), and Tp-e/JTc (P=0.002) were significantly higher in the patients with MVP than in the healthy controls. Positive correlations were found between Tp-e dispersion interval and Tp-e/QTc and an increase in the degree of mitral regurgitation (P=0.012, r=0.42 and P=0.004, r=0.31, respectively). Additionally, positive correlations were detected between JTc dispersion and Tp-e/JTc and an increase in the degree of mitral regurgitation (P=0.032, r=0.20 and P=0.024, r=0.42, correspondingly). In this study, TDR was damaged in children with MVP and was positively correlated with an increase in the degree of mitral regurgitation. It appears that children with MVP are prone to life-threatening ventricular arrhythmias.
二尖瓣脱垂（MVP）患儿可能因复极跨壁离散度（TDR）而易于发生室性心律失常。本研究旨在评估MVP患儿心室复极的改变，并研究其与二尖瓣反流程度的关系。研究了50例MVP患儿和50例年龄及性别匹配的健康儿童作为对照。对所有受试者进行了12导联心电图和超声心动图检查。TDR参数包括QT和QTc间期、QTc离散度、Tp-e间期、Tp-e间期离散度、Tp-e/QT、Tp-e/QTc、JTc、JTc离散度、Tp-e/JT和Tp-e/JTc。50例MVP患者的平均年龄为12.45±2.50岁（女/男：15/35）。两组间QT和QTc间期无显著差异。MVP患者的QTc离散度（P=0.001）、Tp-e离散度间期（P=0.002）、Tp-e/QTc（P=0.001）、JTc离散度（P=0.023）、Tp-e/JT（P=0.004）和Tp-e/JTc（P=0.002）显著高于健康对照组。发现Tp-e离散度间期与Tp-e/QTc以及二尖瓣反流程度增加之间存在正相关（分别为P=0.012，r=0.42和P=0.004，r=0.31）。此外，检测到JTc离散度与Tp-e/JTc以及二尖瓣反流程度增加之间存在正相关（相应地为P=0.032，r=0.20和P=0.024，r=0.42）。在本研究中，MVP患儿的TDR受损，且与二尖瓣反流程度增加呈正相关。看来MVP患儿易于发生危及生命的室性心律失常。
