Evaluation of clinical syntax score i̇n predicting new-onset atrial fibrillation (noaf) and long-term prognosis i̇n patients hospitalized with non-st segment elevation myocardial infarction (NSTEMI).

BACKGROUND: Atrial fibrillation (AF) is the most common supraventricular arrhythmia observed in patients hospitalized with acute coronary syndrome. While its impact on both inhospital and longterm mortality has been documented in patients with Non-ST Segment Elevation Myocardial Infarction (NSTEMI), studies have primarily focused on specific patient populations such as those undergoing percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG), or those with multivessel disease. The Clinical SYNTAX score encompasses not only anatomical angiographic data but also parameters associated with patient outcomes such as age, renal function, and ejection fraction, unlike the SYNTAX score alone. The aims of this study are as follows: 1) to evaluate parameters predicting in-hospital new-onset AF (NOAF) across all NSTEMI populations (PCI, CABG, medical management, non-significant stenosis, single-vessel disease, multivessel disease); 2) to assess the predictive value of the clinical SYNTAX score, which has not been previously evaluated in the entire population, compared to the SYNTAX score alone; and 3) to evaluate the impact of in-hospital NOAF , SYNTAX score, clinical SYNTAX score, and other factors on long-term all-cause mortality and major adverse cardiovascular events (MACE). MATERIALS AND METHODS: This study is a single-center retrospective cohort study conducted in accordance with the Helsinki Declaration. Patients diagnosed with NSTEMI and undergoing coronary angiography during hospitalization at Istanbul University Cerrahpaşa Cardiology Institute between 2011 and 2019 were included. Vital signs, laboratory parameters, and transthoracic echocardiography parameters obtained during hospitalization were recorded. In-hospital new-onset AF was defined as AF confirmed by EKG during intensive care monitoring, routine monitoring, or symptom description, without a previous AF diagnosis. The SYNTAX score was calculated online following coronary angiography. Patients were followed from the index admission until the end of the study period. FİNDİNGS: The study population was evaluated to determine independent predictors for in-hospital NOAF using regression analysis. Due to the strong correlation between SYNTAXscore and clinical SYNTAX score, they were evaluated in separate models. Left atrium (LA) diameter (p < 0.001), age (p < 0.001), female gender (p: 0.007), left ventricular diastolic dysfunction (LVDD) (p: 0.012), and clinical SYNTAX score (p: 0.014) were observed as independent predictive parameters, while it was observed that SYNTAX score alone could not be used for prediction (p: 0.059). ROC-curve analysis with scoring systems revealed that the clinical SYNTAX score had higher sensitivity in predicting AF compared to other risk scores including the SYNTAX score (SYNTAX AUC %95 CI 0.644 (0.588-0.699) p < 0.001, clinical SYNTAX score AUC %95 CI 0.724 (0.673-0.775) P < 0.001). The predictive value analysis for detecting in-hospital new-onset atrial fibrillation using the clinical SYNTAX score indicated that a clinical SYNTAX score ≥ 17.77 had 75% sensitivity and 65% specificity in predicting in-hospital atrial fibrillation. When evaluating patients for long-term mortality over a median follow-up of 86 months, in-hospital AF (p: 0.023), hypertension (HT) (p: 0.013), age (p < 0.001), EF < 60% (p: 0.009), and decline in GFR (p: 0.021) along with clinical SYNTAX score (p: 0.013) were identified as independent predictive parameters. While separate analysis with SYNTAX score showed no significant effect, the cutoff value of SYNTAX > 22 was observed to be a predictive parameter, likely due to the heterogeneous patient population (p: 0.059, p: 0.018 respectively). In the Cox regression model for MACE (death/MI/stroke), in-hospital AF (p: 0.034), HT (p: 0.019), age (p: 0.002), EF < 60% (p:0.032), and clinical SYNTAX score (p: 0.026) were significant, whereas in a separate model with SYNTAX score, only a decline in GFR (p: 0.033) was significant, while SYNTAX score itself was not (p: 0.178). CONCLUSİON: The extension of life expectancy and the increasing prevalence of comorbidities in NSTEMI patients contribute to the continued high incidence of in-hospital AF despite modern PCI era and early revascularization opportunities. In our study, in hospital new-onset AF was identified as an effective parameter for long-term mortality in NSTEMI patients. The clinical SYNTAX score, which combines clinical parameters with anatomical angiographic data, appears to be a more effective parameter for both in-hospital AF and long-term mortality and major adverse cardiovascular events (MACE) compared to the SYNTAX score alone. Therefore, the use of the clinical SYNTAX score for identifying high-risk patients for in-hospital AF and close monitoring of high-risk patient populations for long-term mortality and MACE may be more beneficial than the SYNTAX score alone.