Association among epicardial fat, heart rate recovery and circadian blood pressure variability in patients with hypertension

Abstract

BackgroundEpicardial fat tissue is known to have an unique endocrine function which affect the cardiac autonomic system. Heart rate recovery (HRR) is a simple non-invasive measurement that assesses autonomic nervous system dysfunction. We aimed to investigate the association among epicardial fat thickness (EFT), HRR and circadian blood pressure (BP) variation in patients with hypertension.MethodsA total of 358 consecutive patients who underwent both 24-hour ambulatory BP monitoring (ABPM) and a treadmill test were enrolled. Echocardiographic EFT and HRR, defined as peak heart rate minus heart rate after a 1-min recovery time, were measured. Patients were classified according to the ABPM; 147 patients with hypertension with a dipping pattern at night (dippers), 140 patients with hypertension with a non-dipping pattern at night (non-dippers) and 71 normotensive controls.ResultsEFT was significantly higher in hypertensive patients, especially in the non-dipper group, compared to the controls (non-dippers, 7.5 ± 2.9 mm; dippers, 6.6 ± 1.6 mm; controls, 5.5 ± 2.1 mm; p < 0.001). HRR was significantly lower in both hypertensive groups as compared to the control group and was the lowest in the non-dipper group (non-dipper, 26.6 ± 18.6; dipper, 29.5 ± 21.5; control, 71.4 ± 19.8; p < 0.001). EFT was significantly correlated with age, body mass index, 24-hour mean systolic BP and 24 h mean BP variability, whereas exercise duration, metabolic equivalents (METs) and HRR were inversely correlated with EFT. Furthermore, EFT > 6.7 mm was associated with a blunted HRR with 76 % sensitivity and 61 % specificity (ROC area under curve: 0.71, 95 % confidence interval, CI = 0.65–0.76, p < 0.001). In a multivariate analysis, EFT (odds ratio, OR = 3.53, 95 % CI = 1.20–10.37, p = 0.022) and 24-hour mean BP variability (OR = 1.09, 95 % CI = 1.03–1.16, p = 0.005) were independent predictors of a blunted HRR defined as HRR ≤ 12 beats (n = 63) in patients with hypertension.ConclusionEFT and HRR were significantly correlated with circadian BP variability in patients with hypertension. EFT and circadian BP variability were independent predictors of blunted HRR, which suggests a link between epicardial fat and autonomic dysregulation in hypertension.

Pericardial Fat, Socioeconomic Status, and Biological Responses to Acute Mental Stress

“…We also examined associations between pericardial fat with other measures of autonomic function at rest. We found no association between pericardial fat and resting levels of systolic or diastolic blood pressure, contrary to evidence that has found positive associations between these variables ( 33 , 72 ). One reason for these discrepant findings is differences in statistical covariates.…”

“…One reason for these discrepant findings is differences in statistical covariates. Specifically, Iacobellis et al ( 72 ) only adjusted for gender in their analyses, and Kim et al ( 33 ) did not adjust for any covariates at all, whereas we adjusted for multiple potential confounders known to correlate with both pericardial fat and blood pressure including age, SES, and central adiposity ( 5 , 30 , 73 ). Therefore, associations found in prior studies might have been confounded by sociodemographic factors or central adiposity.…”

“…Some studies have found associations between pericardial fat with blunted heart rate recovery after stress (31)(32)(33). However, all these studies were conducted in clinical populations, such as individuals with hypertension, metabolic syndrome, or obstructive sleep apnea.…”

Change in Pericardial Fat Volume and Cardiovascular Risk Factors in a General Population of Japanese Men

“…It has been reported that PFV is related to heart rate recovery, which was used as an index of cardiac autonomic nervous dysfunction. 21,22 Autonomic nervous dysfunction has been reported to be caused by fat accumulation in visceral adipose tissue in an animal model. 23 PFV shares a common embryonic origin with abdominal visceral fat, 24 and has a positive correlation with abdominal obesity.…”