1.Evaluation of global dispersion of ventricular repolarization in dilated cardiomyopathy patients with heart failure by the characteristic of electrocardiogram
Peixin CONG ; Shijun LI ; Yan ZHANG ; Yunlong XIA ; Xiaomeng YIN ; Shulong ZHANG ; Lianjun GAO ; Yanzong YANG
Chinese Journal of Postgraduates of Medicine 2012;35(10):10-12
ObjectiveTo analyze the characteristic of the T peak-end interval (Tpe) in dilated cardiomyopathy(DCM) patients with heart failure and its significance in evaluation of global dispersion of ventricular repolarization.MethodsFifty-three inpatients were enrolled in this study,which included 28patients with DCM and heart failure (DCM group),and 25 patients with supraventricular tachycardia and without structural heart disease (control group).The Tpe and the dispersion of QT interval (QTd) from the 12-lead surface electrocardiogram(ECG) were acquired and measured,and consequently the corrected numerals of the average of Tpe (Tpe-AVEC),the maximal Tpe (Tpe-MAXC) were acquired.ResultsThe levels of Tpe-AVEC,Tpe-MAXC and QTd in DCM group were significantly higher than those in control group [ ( 106.31 ±26.34) ms vs.(82.72 ± 10.01 ) ms,(234.05 ± 69.75) ms vs.( 119.15 ± 11.55 ) ms,( 119.17 ± 67.62) ms vs.( 39.74 ± 17.04 ) ms ] ( P < 0.05 or < 0.01 ).ConclusionsThe global dispersion of ventricular repolarization is significantly increased in patients with DCM and heart failure.The Tpe-AVEC and Tpe-MAxc are recommended to be used for evaluating the dispersion of ventricular repolarization as the prognostic index in patients with DCM and heart failure.
2.The value of MR amide proton transfer weighted imaging technique in predicting the pathological grade of brainstem glioma
Cong XIE ; Yunyun DUAN ; Xiaobo WANG ; Fenglian ZHENG ; Guirong TAN ; Xing LIU ; Peixin ZHANG ; Rui CHEN ; Ya′ou LIU
Chinese Journal of Radiology 2022;56(2):163-167
Objective:To evaluate the clinical application value of MR amide proton transfer weighted imaging (APTWI) in predicting the pathological grade of brainstem glioma (BSG).Methods:The data of 41 BSG patients in Beijing Tiantan Hospital, Capital Medical University from August 2019 to June 2020 who underwent both MRI and APTWI 2 weeks before surgery and had pathological grading results were retrospectively analyzed. According to the pathological results, 41 patients were classified into high-grade BSG (20 patients) and low-grade BSG (21 patients). Combined with conventional MR images, the signal intensity (%) of amide proton transfer (APT) in the parenchymal area of the tumor was obtained on APTWI images. χ 2 test or independent sample t-test was used to analyze the differences in gender distribution, age and APT signal intensity between patients with high and low grade BSG. Receiver operating characteristic (ROC) curve was drawn to predict the efficacy of APT signal intensity in the differential diagnosis of high and low grade BSG, and Youden index was calculated to obtain the optimal diagnostic threshold; the predictive ability of APT signal intensity was analyzed in combination with Hosmer-Lemeshow goodness of fit test. Results:There was no significant difference in age [(23±18) years, (20±17) years, t=0.97, P=0.340] and gender distribution (9/11, 9/12 for males/females, χ 2=0.02, P=0.890) between high-grade and low-grade BSG patients. The APT signal intensity of high-grade BSG [(3.9±0.9)%] was significantly higher than that of low-grade BSG [(2.8±0.9)%], and the difference had statistical significance ( t=4.16, P<0.001). The area under the ROC curve of APT signal intensity to distinguish high-grade and low grade BSG was 0.836, and with 2.85% as the optimal diagnostic threshold of APT signal intensity, its sensitivity for the diagnosis of high-grade BSG was 90.0% and specificity was 71.4%. The Hosmer-Lemeshow test showed that APTWI had a good predictive ability for BSG grade (χ 2=13.33, P=0.101). Conclusion:APTWI can be applied in distinguishing high grade BSG from low grade BSG, and has clinical value in predicting glioma grading.