Quantitative CT assessment of intrathoracic visceral fat depots and their association with incident heart failure in asymptomatic adults.

BACKGROUND

Epicardial adipose tissue (EAT) is a well-recognized cardiometabolic risk factor. However, the prognostic significance of other intrathoracic visceral adipose tissue (VAT) in heart failure (HF) development and phenotypes remains incompletely understood. This study examined the associations between distinct intrathoracic VAT depots and incident HF in asymptomatic adults.

METHODS

We retrospectively analyzed 3,094 asymptomatic adults (mean age: 49.7 ± 9.7 years) undergoing cardiac CT for health screening. Baseline volumes of intrathoracic VAT depots, including EAT, peri-aortic root fat (PARF), and thoracic peri-aortic adipose tissue (TAT), were quantified using a semi-automated method. Left ventricular mass index (LVMI) was assessed by echocardiography. Associations between intrathoracic VAT and LVMI were evaluated using restricted cubic spline regression. Incident HF was analyzed using Cox regression models and Kaplan-Meier survival curves.

RESULTS

During a median follow-up of 10.3 years, 140 participants developed HF, of whom 89.9% had preserved ejection fraction (HFpEF). Men demonstrated greater intrathoracic VAT accumulation with increasing BMI (p-interaction <0.05). EAT increased more steeply with rising BMI among those who developed HF (p-interaction = 0.011) and showed the strongest association with LVMI. Higher tertiles of intrathoracic VAT volumes and BMI were associated with increased HF incidence (log-rank p < 0.001). After multivariable adjustment, both EAT and PARF remained independently associated with incident HF (hazard ratio per 1-unit Z-score increase: 1.23 [95% CI: 1.04-1.46] and 1.31 [95% CI: 1.09-1.57], respectively), with optimal cutoffs estimated to be 71.37 cm3 and 23.50 cm3, respectively.

CONCLUSION

EAT and PARF are independently associated with incident HF, predominantly HFpEF, and may serve as novel imaging biomarkers for early risk stratification.