The effect of general and spinal anesthesia onfrontal plane QRS-T angle in patients undergoinglower extremity surgery

Objectives: Electrocardiography (ECG) is a non-invasive, easily accessible and low-cost test that has a very important place in the diagnosis and follow-up of cardiovascular diseases. The frontal plane QRS-T angle defines the angular difference between depolarization (QRS axis) and repolarization (T axis) vectors and is an ECG sign of ventricular repolarization heterogeneity. Studies have shown that increased frontal plane QRS-T angle is associated with arrhythmic events and mortality. The aim of our study was to investigate the effect of general and spinal anesthesia on frontal plane QRS-T angle in patients undergoing lower extremity surgery. Methods: All patients who underwent lower extremity surgery in the Department of Anesthesiology and Reanimation, Tokat Gaziosmanpaşa University Faculty of Medicine, Health Research and Application Center between October 2023 and June 2024 were included in our study to meet the inclusion and exclusion criteria. ECG records of the patients included in the study were analyzed before and after surgery. The frontal plane QRS-T angle was calculated from the preoperative and postoperative ECGs of the patients and its change was recorded. The change in frontal plane QRS-T angle before and after the operation was analyzed. Statistical significance value was accepted as <0.05. Results: No statistically significant difference was found between the changes in systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) over time in general anesthesia and spinal anesthesia groups (p=0.511, p=0.896, p=0.682, respectively). After the analysis, no statistically significant difference was found between QT , QTc changes over time in general anesthesia and spinal anesthesia groups (p=0,124, p=0,052). A statistically significant difference was found between the frontal plane QRS-T angle changes over time in the general anesthesia and spinal anesthesia groups (p=0,024). After post-hoc analysis, a statistically significant difference was found between the postoperative 0.min frontal plane QRS-T angle value and the postoperative 30.min and 60.min values in the GA group (p=0.038, p=0.006). Conclusion: In this study, general anesthesia and spinal anesthesia did not have a clinically significant effect on the frontal plane QRS-T angle, which is an indicator of ventricular repolarization heterogeneity. However, since our study was performed in a population not prone to arrhythmia, we may not have found a significant difference. If a study is performed with a larger population of arrhythmia-prone patients, different results may be obtained. Therefore, our findings should be supported by larger-scale and longer-term studies. Keywords: Electrocardiography, Frontal plane QRS-T angle, General anesthesia, Spinal anesthesia.