Background
The aortic knob width (AKW) and the heart rate variability (HRV) were suggested to be related to development of cardiovascular diseases. However, the relationship between them has not been investigated; thus, this study aimed to determine this relationship.
Methods
This study included 587 Koreans aged 18–79 years. Their physical measurements, medical and social histories, blood test findings, and chest radiographs were obtained. The HRV parameters included the standard deviation of the N-N interval (SDNN), root mean square of successive differences (RMSSD), approximate entropy (ApEn), total power (TP), very low frequency (VLF), low frequency (LF), high frequency (HF), and LF/HF ratio, which were measured for 5 minutes. The AKW was measured on chest radiographs by a single reviewer.
Results
The AKW was significantly correlated with the HRV parameters, except for the LF/HF ratio. However, RMSSD and ApEn were not significantly related to the AKW in women. After dividing the participants into quartile groups, the AKW was significantly related to the SDNN, RMSSD, TP, VLF, LF, and HF. The HRV parameter values decreased in the higher AKW quartile groups, the HRV parameter values decreased. After adjusting for sex, drinking status, exercise habits, smoking status, waist circumference, and triglyceride, low-density lipoprotein cholesterol, fasting blood sugar, and glycated hemoglobin levels, the AKW showed significant negative associations with the HRV parameters, except for the LF/HF ratio.
Conclusion
The AKW is significantly associated with the HRV parameters of SDNN, RMSSD, ApEn, TP, VLF, LF, and HF.

Background
Both aortic knob width and metabolic syndrome are suggested to be related to atherosclerosis and cardiovascular diseases. However, the association between aortic knob width and metabolic syndrome is unknown. This study aimed to explore this relationship.
Methods
Participants were 3,705 Korean adults aged 18–79 years who visited the health promotion center of a general hospital. Data on chest radiography, physical measurements, medical and social history, and blood tests were collected. We defined metabolic syndrome according to the National Cholesterol Education Program Adult Treatment Panel III criteria. A single reviewer measured aortic knob width on chest radiography.
Results
Aortic knob width was significantly correlated with age; body mass index; waist circumference; systolic and diastolic blood pressures; total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, fasting glucose, glycated hemoglobin, insulin, and uric acid levels; and homeostatic model assessment of insulin resistance values. Aortic knob width significantly increased as the number of metabolic syndrome components increased. Moreover, metabolic syndrome component values tended to increase across the quartile groups of aortic knob width after adjusting for age, exercise, smoking status, and alcohol use. Through receiver operating characteristic curve analysis, we determined the clinically useful cutoff value for aortic knob width to be 30.47 mm in premenopausal women.
Conclusion
Aortic knob width was found to be significantly related to metabolic syndrome and its individual components.

Citations

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  Bulletin of Cardiovasculer Academy.2024;[Epub]     CrossRef
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  Steven Magera, Senai Goitom Sereke, Emmy Okello, Faith Ameda, Geoffrey Erem
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