Evaluation of serum YKL-40 levels in patients presenting to the emergency department with chest pain

Coronary artery diseases are among the leading causes of mortality and morbidity in developed and developing countries. In acute coronary syndrome presentations, which are frequently encountered in the emergency department, rapid diagnosis and appropriate treatment are of vital importance. Although tests such as troponin are standard, the possibility of negative troponin in unstable angina cases and elevations in some non-cardiac conditions highlight the need for additional biomarkers. In this study, we aimed to investigate the diagnostic value of chitinase-3-like protein 1 as a candidate biomarker in acute coronary syndrome. Our study was conducted as a single-center study in a tertiary university emergency department. A total of 88 individuals who met the inclusion criteria 32 Non–ST-elevation myocardial infarction, 28 unstable angina, and 28 healthy controls were included. Chitinase-3-like protein 1 levels were measured at presentation; demographic data, basic laboratory results, electrocardiogram/echocardiography, and standard risk scores were recorded. Statistical significance was set at p<0.05. Among the 60 patients in our study, the mean age was 62.27±13.82 years (minimum–maximum: 31–96), and 65% (n=39) were male. When the ages of the control and total patient groups were compared, the patient group was older (p<0.001). Sex distribution was similar between control and patient groups. Chitinase-3-like protein 1 levels were significantly higher in the patient group compared with the control group; in subgroup analyses, levels were higher than controls in both Non–ST-elevation myocardial infarction and unstable angina. Chitinase-3-like protein 1 was 552.57 in the control group, 875.43 in the Non–ST-elevation myocardial infarction group, and 768.29 in the unstable angina group. In Receiver Operating Characteristic analysis, Chitinase-3-like protein 1 showed significant discriminative ability for control– Non–ST-elevation myocardial infarction (Area Under the Curve≈0.73) and moderate discriminative ability for control–unstable angina (Area Under the Curve ≈0.69); it was not significant for – Non–ST-elevation myocardial infarction- unstable angina discrimination. Chitinase-3-like protein 1 did not show a marked difference across risk score groups at presentation or across electrocardiogram/echocardiography subclasses. In conclusion, Chitinase-3-like protein 1 is a biomarker that increases in the presence of acute coronary syndrome and provides significant discrimination between control and acute coronary syndrome. Although it does not appear sufficient on its own to distinguish – Non–ST-elevation myocardial infarction from unstable angina, it may be used as a complementary tool alongside clinical evaluation and standard tests in the emergency department, particularly because it can provide an additional risk signal for unstable angina and offers a practical cutoff value. Larger, multicenter studies are needed to validate these findings.