Novel combined index of cardiometabolic risk related to periarterial fat improves the clinical prediction for coronary artery disease complexity.

BACKGROUND AND AIMS: Cardiovascular (CV) risk assessment based on conventional risk factors has a limited performance in the prediction of obstructive coronary artery disease (CAD). Therefore, our aim was to provide a complete assessment on the associations between single or combined cardiovascular ultrasound indexes and the complexity of CAD in high and very-high risk patients.

METHODS: Two hundred fifteen patients scheduled for elective coronary angiography were enrolled in the study (F/M: 80/135 pts; age: 61.8 ± 7.9 years). Detailed clinical characteristics, including several obesity parameters, and the following ultrasound indexes were obtained: carotid intima-media thickness (IMT) and extra-media thickness (EMT), epicardial fat thickness (EFT) and intra-abdominal fat thickness (IAT). CAD severity and complexity were assessed based on the well-evidenced SYNTAX score (SS) algorithm.

RESULTS: The study patients (79% with a very high CV risk) had central obesity (77%), and arterial hypertension (81%), one-third (37%) had diabetes and most of the individuals (74%) were current or previous smokers. In the study group, male sex, higher number of CV risk factors, diabetes and increased carotid vascular indexes (IMT or EMT ≥ 900 μm) were associated with significantly higher SS (p < 0.05). Paradoxically, obese patients revealed a significantly lower SS compared to non-obese individuals (3.65 ± 6.66 vs. 5.93 ± 8.8; p < 0.01), which was not explained by the number of CV risk factors or age. All the ultrasound indexes (except for visceral fat - IAT) revealed significant associations with the SS and the highest correlation coefficient was found for PATIMA combined index (r = 0.45; p < 0.01). Hence, none of the obesity-related clinical indexes showed any associations with CAD complexity. Multivariate regression analysis showed that male sex, chronic kidney disease and the PATIMA index were independently associated with the Syntax Score. The ROC analysis showed that the highest sensitivity (71% and 82%) and specificity (77% and 72%) in prediction of either SS > 1 or SS > 7 were found for the combined PATIMA index (negative predictive value = 92% for SS > 7).

CONCLUSIONS: We present the first study showing that a combination of ultrasound indexes related to periarterial fat and vascular wall (PATIMA index) is associated with more complex CAD in high and very-high risk patients. PATIMA index revealed improved predictive value compared to other single ultrasound indexes and clinical risk assessment.