Tests of cardiovascular reflexes and heart rate variability are reliable and noninvasive and therefore useful in children with suspected autonomic nerve dysfunction. The aim of this study was to calculate normal reference values and investigate the relationship between car\u00addiovascular reflex ratios, gender and age. A batery of cardiovascular tests was performed in 81 healthy children, aged 7 to 16 years. The Valsalva, deep breathing, handgrip and ortho\u00adstatic ratios were calculated and changes in blood pressure were measured during handgrip (diastolic) and orthostatic (systolic and dias\u00adtolic) tests. Heart rate variability was quantified by spectral analysis for low and high frequency bands (LFB and HFB), and the LFB\/HFB ratio was calculated. Normal Valsalva, deep breathing, handgrip and orthostatic ratios and integrals of LFB and HFB were calculated for two-year age groups (e.g. 7\u20138 year olds, 9\u201310-year olds etc.) There was a significant negative correlation between the handgrip ratio, systolic blood pressure during orthostatic test, supine LFB\/HFB ratio and age. There was also a significant positive correlation between the supine HFB and age. The deep breathing ratio and HFB integral were signifcantly higher in girls aged 11 to 12 years, and the hand\u00adgrip diastolic pressure increase was greater in girls 15 to 16 years of age. Cardiovascular tests are a safe and reliable tool for the evaluation of autonomic nerve function in children. Since age-related variations are more dynamic in chil\u00addren than in adults, we would recommend that reference values for children be determined in groups of smaller age range (e.g. two years). Also, gender grouping should be done when determining reference values in children.<\/p>\n","protected":false},"excerpt":{"rendered":"
Tests of cardiovascular reflexes and heart rate variability are reliable and noninvasive and therefore useful in children with suspected autonomic nerve dysfunction. The aim of this study was to calculate normal reference values and investigate the relationship between car\u00addiovascular reflex ratios, gender and age. A batery of cardiovascular tests was performed in 81 healthy children, […]<\/p>\n","protected":false},"author":18,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[333,407,426,433,441,420],"tags":[],"class_list":["post-4644","post","type-post","status-publish","format-standard","hentry","category-4-1998-archive","category-clinical-research-paper","category-internal-medicine","category-neurology","category-pediatrics","category-physiology"],"acf":[],"yoast_head":"\n