Background and aim of the study: Epicardial fat tissue (EAT) is associated with coronary as well as aortic valve calcification. The study aim was to determine whether EAT thickness is different in patients with and without aortic valve stenosis (AVS).
Methods: A cohort of 200 consecutive patients with severe AVS and 200 matched patients without AVS were included retrospectively in the study. EAT thickness was quantified, using transthoracic echocardiography, as the space between the epicardial wall of the myocardium and the visceral layer of the pericardium. Unadjusted and risk factor-adjusted logistic regression analysis was used to determine the association of EAT thickness with the presence of AVS.
Results: Overall, 400 patients (182 males, 218 females; mean age 79.6 ± 6.5 years) were included in the study. EAT thickness was significantly higher in patients with severe AVS (7.4 ± 0.3 mm versus 5.8 ± 0.2 mm; p <0.0001 for patients with and without AVS, respectively). In logistic regression analysis, an increase in EAT by one standard deviation was associated with a two-fold increased occurrence of AVS (OR [95%CI]: 2.10 [1.65-2.68]; p <0.0001). Associations remained stable upon adjustment for age, gender and traditional cardiovascular risk factors (2.08 [1.59-2.72]; p <0.0001). Body mass index (BMI) -specific subgroup analysis showed that the link between EAT and AVS was independent of BMI (1.78 [1.15-2.75], 2.62 [1.71- 4.02], and 2.22 [1.36- 3.62], for BMI <25 kg/m2, 25-30 kg/m2, and >30kg/ m2, respectively). EAT, in addition to traditional cardiovascular risk factors, significantly improved the area under the receiver operating characteristic curve (from 0.70 to 0.76; p = 0.003).
Conclusions: EAT thickness is significantly associated with severe AVS, independent of traditional risk factors. While further studies are needed to confirm these results, the present findings support the hypothesis that EAT may influence sclerosis of the aortic valve.