Association of epicardial fat thickness with TIMI risk score

We read the article“Association of epicardial fat thickness with TIMI risk score in NSTEMI/USAP patients” by Ozcan et al. [1] with great interest. The authors aimed to investigate the association between TIMI risk score and epicardial fat thickness (EFT) in patients with non-ST-elevation myocardial infarction (NSTEMI) and unstable angina pectoris (USAP). They concluded that EFT is independently associated with TIMI risk score and may be an emerging risk factor for adverse events in NSTEMI/USAP patients. We thank the authors for their contribution of the present study, which is successfully designed and documented. EFT measurement with echocardiography has several advantages, including its low cost, easy accessibility, rapid applicability, and good reproducibility. EFT has a three-dimensional distribution, and two-dimensional echocardiography cannot give an adequate window of all cardiac segments, especially in obese subjects, and is highly dependent on acoustic windows [2]. It is widely recognized that an accumulation of EFT is strongly related to coronary artery disease (CAD). EFT amount may contribute to systemic inflammation beyond traditional cardiovascular risks and body fat composition. EFT measured by echocardiography has been known to be associated with metabolic syndrome [3]. Additionally, echocardiography-based EFT measurement was related to several metabolic abnormalities and independently associated with fatty liver disease [4]. Also, the duration of hormone therapy (HT) may be different in these patients. We think that the results of the study would be more robust if the authors had mentioned these factors including the duration of HT and liver function tests. EFT can also be affected by atherosclerotic risk factors such as alcohol consumption, hypothyroidism [5], and higher inflammatory status [3], for example, an inflammatory disease, cardiac syndrome X, and infection [6]. In the present study, the authors did not mention these possibly contributing factors. It would have been better if the authors had given information about these factors. Furthermore, the severity of CAD was evaluated by calculation of Gensini scores in the present study. However, the SYNTAX score (SS) may also be used for grading of coronary complexity based on angiographic visual assessment. The addition of clinical risk factors to the SS has been shown to potentially further augment its utility in the objective evaluation of the severity of CAD. The Logistic Clinical SXscore consisting of four continuous variables including SXscore, age, creatinine clearance, and left ventricular ejection fraction substantially enhances the risk stratification of CAD patients for the outcome of long-term all-cause death compared with the SXscore in isolation. The Logistic Clinical SXscore was able to accurately distinguish patients with or without a clinical outcome and could accurately predict individual patient risk without underor over-estimating risk [7]. Second, we strongly believe that it would be better to give interobserver and intraobserver variability for CAD severity in the current study. Finally, EFT itself without other inflammatory markers may not provide information to clinicians about systemic inflammation. Therefore, we think that it should be evaluated together with other serum inflammatory markers. We believe that these findings will help evaluate the results of further studies on EFT and TIMI risk score in acute coronary syndrome patients.