Retrospective analysis of electrocardiographic (EKG) and laboratory parameters in patients presenting to the emergency department with upper abdominal pain

Retrospectıve Analysıs Of Electrocardıographıc (Ecg) And Laboratory Parameters In Patıents Presentıng To The Emergency Department Wıth Upper Abdomınal Paın Objective: The primary objective of this study was to analyze the diagnostic and prognostic efficacy of electrocardiographic findings, including the FQRS-T angle, as well as laboratory parameters in patients presenting to the emergency department (ED) with upper abdominal pain. These parameters included complete blood count, C-reactive protein (CRP), inflammatory indices (SII, SIRI, AISI, NLR), and ECG measures (FQRS-T, QTc). Our secondary objective was to assess whether any of these parameters had superiority over the others in diagnosing conditions and predicting survival. Materials and Methods: This retrospective, randomized, observational, single-center study was conducted at the Emergency Medicine Department of Süleyman Demirel University Medical Faculty Hospital. Between September 15, 2022, and March 15, 2025, patients who presented with abdominal pain and were diagnosed with pancreatitis, gallbladder pathologies, gastroenteritis, or gastritis were identified, and those with complete medical records were included. Demographic data (age, sex), vital signs, laboratory results, and ECG findings were collected and analyzed. Results: Of the 199 patients included, 54.3% (n=108) were female, and 45.7% (n=91) were male, with a mean age of 64.61±14.96 years (range: 29–92). The overall mortality rate was 12.1% (n=24). Patients were grouped into four main diagnoses: 25.6% had pancreatitis, 24.6% gallbladder pathologies, 25.1% gastroenteritis, and 24.6% gastritis. There was no statistically significant difference in mortality between genders (p>0.05). However, significant differences were observed in age, heart rate, oxygen saturation, respiratory rate, systolic blood pressure, and diastolic blood pressure between survivors and non-survivors (p<0.05). Among laboratory parameters, CRP showed a statistically significant association with mortality, while FQRS-T and QTc were the significant ECG measures (p<0.05). Subgroup analyses by diagnosis revealed that CRP was markedly higher in gallbladder pathologies, whereas WBC, NLR, SII, AISI, and SIRI were significantly higher in pancreatitis (p<0.05). According to the ROC analysis, CRP had the highest predictive power for mortality (AUC=0.890). When the cutoff value for the FQRS-T angle was set at 47, it demonstrated high sensitivity for predicting mortality (AUC=0.701). Spearman's correlation indicated a link between prolonged hospital stays and elevated NLR, as well as an increased FQRS-T angle (p=0.039, r=0.231; p=0.004, r=0.319, respectively). A 30-day survival analysis showed that patients with an FQRS-T angle ≤47 had a higher survival rate compared to those with an angle >47 (log-rank p=0.001). In the logistic regression model, each one-unit increase in the FQRS-T angle raised mortality risk by 1.013 times (OR: 1.013, 95% CI: 1.001– 53 1.027, p=0.028), while each one-unit increase in CRP enhanced mortality risk by 1.01 times (OR: 1.010, 95% CI: 1.001–1.019, p=0.026). Conclusion: Our findings suggest that the FQRS-T angle serves as an independent predictor of mortality in patients presenting to the ED with upper abdominal pain. Given its noninvasive, cost-effective, and easily obtainable nature, we believe broader adoption of the FQRS-T angle in routine clinical practice could provide significant benefits for early risk stratification and management. Keywords: Upper Abdominal Pain, FQRS-T Angle, Emergency Department, Electrocardiography, Inflammatory Indices, CRP