Immune-Inflammatory Markers in Aortic Dissection

Overview

Identifying early on which patients with acute aortic dissection require closer monitoring may help with care planning. If simple, inexpensive values obtained from routine blood tests can provide additional information for assessing risk, this knowledge could in the future help physicians follow their patients more effectively. The aim of this study is to investigate this possibility scientifically. It is based on the evaluation of information obtained from blood tests that are already being performed. Its purpose is to generate general knowledge that may contribute to the care of future patients. The study itself does not change decisions about your treatment; all decisions regarding your treatment and follow-up rest with your doctor, who evaluates your condition in its entirety. It is designed to evaluate the relationship between preoperative/postoperative systemic immune-inflammatory and nutritional markers (SII, NLR, PLR, CAR, PNI) and indicators of mortality and morbidity (length of stay and changes in kidney function) in patients with acute aortic dissection. The goal is to investigate the potential of easily accessible laboratory parameters to contribute to risk stratification. The relationship between the markers and outcomes will be analyzed using appropriate statistical methods. This study is based on the evaluation of information in patients' existing medical records and blood tests. The data are processed in accordance with the relevant ethical rules and privacy principles, with patient identity kept confidential. Taking part in the study does not require any additional procedure, additional blood draw, or change in treatment.

This is a single-center observational study based on a retrospective review of the records of patients who underwent surgical treatment for acute aortic dissection at the Bursa City Hospital Operating Room between January 1, 2022, and March 1, 2026. The study was planned and conducted in accordance with the principles of the Declaration of Helsinki and was approved by the Bursa City Hospital Scientific Research Ethics Committee (Decision No: 2026-12/9). A total of 127 adult patients who underwent surgical treatment with a diagnosis of acute aortic dissection during the specified period were included in the study. The diagnosis was confirmed through clinical findings and radiological examinations, primarily computed tomography angiography, and the type of dissection was recorded. Inclusion criteria: being 18 years of age or older and having undergone surgical intervention for acute aortic dissection. Patients meeting the following criteria were excluded from the study: those with a diagnosis of chronic aortic dissection; cases with missing preoperative laboratory data or clinical outcome records; patients with hematological malignancies or disorders such as leukemia, lymphoma, or immune thrombocytopenic purpura (ITP); those with chronic inflammatory or autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus (SLE), or ankylosing spondylitis; patients with active steroid use, immunosuppressive therapy, or recent chemotherapy; and those diagnosed with decompensated liver failure or end-stage renal disease (ESRD). These exclusion criteria were established to ensure the reliability of the results by eliminating patients with comorbidities or treatments that could directly affect neutrophil, platelet, and lymphocyte counts-the study's primary independent variables. All data were obtained from the hospital's electronic information system and patient files. Age, gender, dissection type, and left ventricular ejection fraction were recorded as demographic and clinical variables. Preoperative blood values were recorded prior to the surgical intervention. The preoperative laboratory parameters examined included white blood cell (WBC) count, neutrophil, lymphocyte, and platelet counts, hemoglobin, D-dimer, creatine kinase-MB (CK-MB), troponin, creatinine, estimated glomerular filtration rate (eGFR), albumin, and C-reactive protein (CRP) levels. Lactate, partial pressure of carbon dioxide (pCO2), and partial pressure of oxygen (pO2) values were obtained from preoperative arterial blood gas analysis. In surviving patients, postoperative values for the same markers were also calculated. The composite markers investigated were calculated for each patient using the following formulas based on preoperative laboratory values: Systemic Immune-Inflammation Index (SII): (neutrophil count × platelet count) / lymphocyte count Neutrophil-to-Lymphocyte Ratio (NLR): neutrophil count / lymphocyte count Platelet-to-Lymphocyte Ratio (PLR): platelet count / lymphocyte count CRP-to-Albumin Ratio (CAR): CRP / albumin Prognostic Nutritional Index (PNI): (10 × serum albumin \[g/dL\]) + (0.005 × total lymphocyte count \[/mm3\]) SII × Lactate Composite Index: SII × preoperative arterial lactate (mmol/L) The SII × Lactate composite index was defined to combine systemic inflammatory load (SII) and tissue hypoperfusion/anaerobic metabolism (lactate) into a single value. In surviving patients, postoperative values of SII, NLR, PLR, CAR, and PNI were also calculated using the same formulas and compared with preoperative values. The primary outcomes of the study were perioperative exitus and in-hospital mortality. Secondary outcomes included length of stay in the intensive care unit and hospital, the development of renal failure in surviving patients, and intraoperative and postoperative blood product usage. Renal failure was evaluated using two separate definitions: (i) eGFR falling below 60 mL/min/1.73 m² at the 1st and/or 3rd postoperative month; (ii) the ratio of the 1st and/or 3rd month postoperative creatinine to preoperative creatinine being greater than 1.5. Renal function parameters during the follow-up period were evaluated only in surviving patients.