https://www.selleckchem.com/products/jq1.html Introduction Long QT syndrome (LQTS) is a congenital disorder characterized by a prolongation of the QT interval on electrocardiograms (ECGs) and a propensity to ventricular tachyarrhythmias, which may lead to syncope, cardiac arrest, or sudden death. T-wave alternans (TWA) refers to the periodic beat-to-beat alternation of T-wave shape, polarity and amplitude on surface ECG during regular heart rhythm. In this report, a case of long QT syndrome with KCNQ1 gene mutation induced TWA in the head-up tilt test (HUTT), which has not been reported yet. Patient concerns A 6-year-old boy presented with loss of consciousness twice, 5 months in duration. The boy's ECG showed prolonged QT interval (QTc = 600 ms, QTc = QT/RR). During HUTT test, QT interval was significantly prolonged (QTc = 716 ms) based on macroscopic TWA. Diagnosis The patient was diagnosed with 1. Long QT syndrome type 1(LQT1); 2. Vasovagal syncope (VVS) INTERVENTIONS Metoprolol 12.5 mg was given orally twice a day. The child was told avoid standing for a long time and strenuous exercises. Outcomes There was no syncope or arrhythmia occurred during hospitalization and follow-up for 1 year. Conclusions VVS may exist in patients with long QT syndrome. Increased sympathetic tone during the early stage of HUTT may induce macroscopic TWA in long QT syndrome with KCNQ1 gene mutation.Background The interleukin-10 (IL-10)-819T/C polymorphism has been indicated to be correlated with ischemic stroke susceptibility, but this relationship remains controversial. A meta-analysis was conducted to investigate the potential association between IL-10-819T/C polymorphism and ischemic stroke risk. Methods Databases including Pubmed, Embase, and CNKI were searched. Data were extracted and odds ratios (OR) with 95% confidence intervals (CI) were calculated. Results Eight case-control studies with 1832 cases and 1520 controls were included in this meta-analysis. IL-10-819T/C polymorphi