Objective To investigate the relationship between T wave morphology in lead aVR, QRS-T angle and prognosis of malignant arrhythmia (MA) after acute ST-segment elevation myocardial infarction (ASTEMI).

Methods The clinical data of 80 patients with MA (MA group) after ASTEMI who received direct percutaneous coronary intervention (PCI) were analyzed retrospectively, and 80 patients without MA (non-MA group) in ASTEMI in the same period were selected. All patients underwent electrocardiogram (ECG) examination before operation, and the differences of the T wave morphology in lead aVR and planar QRS-T angle between the two groups were compared. Follow-up to June 2021, patients in MA group were divided into survival group and death group according to their survival situation. The T wave morphology in aVR lead and plane QRS-T angle were compared between the two groups, and univariate and multivariate Cox regression were used to analyze the related factors affecting the prognosis of MA after ASTEMI. The survival curve was drawn to evaluate the predictive value of T wave morphology in lead aVR and plane QRS-T angle on the prognosis of MA after ASTEMI.

Results The proportion of upright T wave in lead aVR and planar QRS-T angle ＞90°of the MA group were higher than those in the non-MA group (P ＜ 0.05). As of the follow-up time, 48 out of 80 patients survived and 32 died. Compared with the survival group, the proportion of upright T wave in lead aVR, proportion of QRS-T angle ＞90°, LVEF and Cr levels, time from onset to PCI, and proportion of high-level Killip grading in the death group were all higher, and the differences were statistically significant (P ＜ 0.05 to P ＜ 0.01). Cox regression analysis showed that a high proportion of upright T waves in lead aVR, a high proportion of QRS-T angle ＞90°, a high proportion of LVEF, and a high Killip grade were all risk factors affecting the prognosis of malignant arrhythmia after ASTEMI (P ＜ 0.05 to P ＜ 0.01). The Kaplan-Meier survival curve showed that the survival rate of upright T waves in lead aVR group was lower than that of the non-upright group, and the survival rate of the QRS-T angle ＞90° group was lower than that of the ≤90° group, with statistically significant differences (P ＜ 0.05).

Conclusion The T wave morphology in lead aVR and the QRS-T angle are related factors that affect the prognosis of MA after ASTEMI, and have certain reference value for the prognosis of MA after ASTEMI.