Relationship between left ventricular ejection fraction and serum potassium level and postoperative recurrence of ventricular tachycardia after myocardial infarction

Yang Hao; Du Wei; Dong Qingshan; Li Xianjin

doi:10.3969/j.issn.1674-4055.2023.08.15

Abstract：Objective This study aims to investigate the relationship between left ventricular ejection fraction(LVEF),serum potassium levels,and the postoperative recurrence of ventricular tachycardia(VT)in patients with myocardial infarction.Methods A retrospective analysis was conducted on the clinical data of 335 patients with VT after myocardial infarction who underwent catheter ablation at Xu Zhou Central Hospital's Cardiovascular Department between January 2016 and January 2021.After a 12-month follow-up period,the patients were divided into two groups based on VT recurrence:the recurrence group and the non-recurrence group.A comparison was made between the two groups in terms of LVEF,serum potassium levels,and clinical data.Logistic regression analysis was employed to identify the risk factors for postoperative VT recurrence after myocardial infarction.Receiver operating curves(ROCs)were generated to assess the predictive ability of LVEF and serum potassium levels regarding postoperative VT recurrence after myocardial infarction.Results Among the 335 patients with VT after myocardial infarction,30 experienced postoperative recurrence,accounting for 8.96%of the cases.These 30 patients comprised the recurrence group,while the remaining 305 patients constituted the non-recurrence group.Compared to the non-recurrence group,the recurrence group exhibited lower average LVEF and serum potassium levels,as well as increased proportions of smoking,hypertension,cardiac ventricular aneurysm,and hemodynamic instability during VT episodes(P<0.05).Logistic stepwise regression analysis revealed that smoking,hypertension,cardiac ventricular aneurysm,hemodynamic instability during VT episodes,LVEF,and serum potassium level were all identified as risk factors for postoperative VT recurrence after myocardial infarction(P<0.05).ROC analysis indicated that the optimal cut-off points for predicting postoperative VT recurrence after myocardial infarction were 47.55%for LVEF and 3.04 mmol/L for serum potassium levels.The individual and combined detection of these two factors yielded AUC values of 0.858(95%CI:0.816～0.894,P<0.05),0.869(95%CI:0.828～0.903,P<0.05),and 0.943(95%CI:0.861～0.984,P<0.05),respectively.The combined detection demonstrated superior predictive value compared to LVEF alone(P=0.032)and serum potassium level alone(P=0.029).Conclusion LVEF and serum potassium levels exhibit a high predictive efficacy for postoperative VT recurrence in patients with myocardial infarction,offering valuable insights for clinical prevention.