Abstract 4124281: Dexmedetomidine for junctional ectopic tachycardia in patients undergoing tetralogy of Fallot repair: a meta-analysis of randomized controlled trials

Background: Junctional ectopic tachycardia (JET) occurs in 2 to 22% of patients after cardiac surgery for congenital heart diseases, including tetralogy of Fallot (TOF) repair. Dexmedetomidine emerged as a potential drug to prevent JET in these patients. This systematic review and meta-analysis aimed to evaluate the efficacy of dexmedetomidine in JET in patients undergoing TOF repair. Methods: We systematically searched PubMed, Embase, and Cochrane databases for randomized controlled trials (RCTs) analyzing the use of dexmedetomidine in patients undergoing TOF repair. We pooled risk ratios (RR) for binary outcomes, and mean differences (MD) for continuous outcomes with 95% confidence intervals (CI) with a random-effects model. We performed a trial sequential analysis (TSA) to assess the random risk of incidence of JET. We used R version 4.3.2 and TSA version 0.5.9.10 for statistical analyses. Results: Our meta-analysis included 5 RCTs comprising 546 patients, of whom 268 (49%) were randomized to dexmedetomidine. Compared with control, dexmedetomidine significantly reduced the incidence of JET (RR 0.46; 95% CI: 0.30 to 0.71; p<0.05; Figure A). However, there were no significant differences in mortality (RR 0.45; 95% CI: 0.12 to 1.71; p=0.24; Figure B) between groups. In addition, dexmedetomidine also reduced the length of intensive care unit (ICU) stay (MD -7.75 hours; 95% CI: -15.08 to -0.41; p<0.05; Figure C). There were no significant differences in ionotropic score (MD -0.97 ug.min/Kg; 95 % CI: -1.98 to 0.18; p=0.10; Figure D), and ventilation time (MD -2.29 hours; 95% CI: -8.39 to 2.41; p=0.27; Figure E). For the primary endpoint, TSA suggested a low risk of type 1 error; therefore, this result may be conclusive. Conclusion: In patients undergoing TOF repair surgery, dexmedetomidine significantly reduced the incidence of JET and the length of ICU stay.