Background: Epicardial fat thickness (EFT) has been shown to be independently associated with coronary artery disease (CAD). EFT measured in 2D echocardiogram strongly correlates with visceral adipose tissue volume in MRI and can be a marker of prognosis in patients with clinical CAD.
Procedure and Methods: Eighty-one subjects for elective coronary angiography with high suspicion for CAD were enrolled. We measured EFT in PLAX and SAX view prior or immediately after the angiogram. The SPS score based on clinical parameters were likewise obtained, patients were stratified to high risk (SPS ≥8) and low risk (SPS <8).The subjects were classified to two groups based on Gensini score (non-severe CAD <20 and severe CAD < 20). To determine its ability to predict atleast 1 significant obstructive lesion, additional study was done and patients were re classified to two groups; non-obstructive CAD (Gensini <8) and obstructive CAD group (Gensini ≥8). The correlation and accuracy for determining severity and presence of CAD were examined.
Results: Age, male gender, low HDL levels, increased left atrial volume index, the presence of aortic valve calcification and diastolic dysfunction as well as SPS ≥8 significantly influence severity of CAD by Gensini. EFT measured in SAX view showed a sensitivity of 87.04%, specificity of 81.48%, negative predictive value of 75.86% and positive predictive value of90.38% in predicting severe CAD (c=0.919) with a cut off of 0.28 cm. EFT measured in PLAX view was able to predict severe CAD (c=0.900) with a sensitivity of 81.48%, specificity of 77.78%, NPV of 67.74% and PPV of 88% with a cut off of 0.24cm. SPS was able to predict severe CAD (c=O.7984) with a sensitivity of 85.19%, specificity of 55.56%, NPV of 65.22% and PPV of 79.31 % among high-risk patients. Additional studies showed EFT measured in SAX better predicts atleast 1 obstructive CAD (c=0.8667) with a sensitivity of 81.67%, specificity of 80.95%, NPV of60.71 % and PPV of 92.45% using a cut off of 0.26 cm.
Conclusion: EFT measured in PLAX and SAX by 2D echocardiography as well as SPS scoring system predicted severe coronary artery stenosis in patients with high suspicion for CAD. The EFT measured in SAX view showed the highest sensitivity, specificity and negative and positive predictive values in predicting severe CAD as well as the presence of significant (≥70% lesion) coronary artery stenosis. This can be a marker of prognosis in Filipino patients who presented with clinical symptoms highly suggestive of CAD.