Associations of region-specific visceral adiposity with subclinical atrial dysfunction and outcomes of heart failure

Association of Region-Specific Cardiac Adiposity With Dysglycemia and New-Onset Diabetes

Background Visceral adipose tissue is assumed to be an important indicator for insulin resistance and diabetes beyond overweight/obesity. We hypothesized that region-specific visceral adipose tissue may regulate differential biological effects for new-onset diabetes regardless of overall obesity. Methods and Results We quantified various visceral adipose tissue measures, including epicardial adipose tissue, paracardial adipose tissue, interatrial fat, periaortic fat, and thoracic aortic adipose tissue in 1039 consecutive asymptomatic participants who underwent multidetector computed tomography. We explored the associations of visceral adipose tissue with baseline dysglycemic indices and new-onset diabetes. Epicardial adipose tissue, paracardial adipose tissue, interatrial fat, periaortic fat, and thoracic aortic adipose tissue were differentially and independently associated with dysglycemic indices (fasting glucose, postprandial glucose, HbA1c, and homeostasis model assessment of insulin resistance) beyond anthropometric measures. The superimposition of interatrial fat and thoracic aortic adipose tissue on age, sex, body mass index, and baseline homeostasis model assessment of insulin resistance expanded the likelihood of baseline diabetes (from 67.2 to 86.0 and 64.4 to 70.8, P for ∆ ꭕ²: <0.001 and 0.011, respectively). Compared with the first tertile, the highest interatrial fat tertile showed a nearly doubled risk for new-onset diabetes (hazard ratio, 2.09 [95% CI, 1.38-3.15], P<0.001) after adjusting for Chinese Visceral Adiposity Index. Conclusions Region-specific visceral adiposity may not perform equally in discriminating baseline dysglycemia or diabetes, and showed differential predictive performance in new-onset diabetes. Our data suggested that interatrial fat may serve as a potential marker for new-onset diabetes.

Associations of region-specific visceral adiposity with subclinical atrial dysfunction and outcomes of heart failure

AIMS

Excessive visceral adiposity (VAT) plays an essential role in metabolic derangements with those close to heart further mediates myocardial homeostasis. The disparate biological links between region-specific VAT and cardiometabolic profiles as mediators influencing atrial kinetics remain unexplored.

METHODS AND RESULTS

Among 1326 asymptomatic individuals, region-specific VAT including peri-aortic root fat (PARF) and total pericardial fat (PCF) of cardiac region, together with thoracic peri-aortic adipose tissue (TAT), was assessed using multiple-detector computed tomography. VAT measures were related to functional left atrial (LA) metrics assessed by speckle-tracking algorithm and clinical outcomes of atrial fibrillation (AF) and heart failure (HF). Multivariate linear regression models incorporating body fat, metabolic syndrome, and E/TDI-e' consistently demonstrated independent associations of larger PARF/PCF with peak atrial longitudinal systolic strain (PALS) reduction, higher LA stiffness, and worsened strain rate components; instead, TAT was independently associated with cardiometabolic profiles. PARF rather than PCF or TAT conferred independent prognostic values for incident AF/HF by multivariate Cox regression (adjusted hazard ratio: 1.56, 95% confidence interval: 1.17-2.08, P = 0.002) during a median of 1790 days (interquartile range: 25th to 75th: 1440-1927 days) of follow-up, with subjects categorized into worst PALS and largest VAT tertiles demonstrating highest events (all log-rank P < 0.001). Mediation analysis showed that higher triglyceride and lower high-density lipoproteins may serve as intermediary factors for effects between VAT and LA functional metrics, with lesser role by glucose level.

CONCLUSIONS

Visceral adiposity surrounding atrial region was tightly associated with subclinical atrial dysfunction and incident AF or HF beyond metabolic factors. Instead, peri-aortic adiposity may mediate their toxic effects mainly through circulating cardiometabolic profiles.