Heart rate variability: the comparison between high tension and normal tension glaucoma

Abstract

RelevanceVascular factors may be involved in the development of both high tension glaucoma (HTG) and normal tension (NTG) glaucoma; however, they may be not exactly the same. Autonomic dysfunction characterized by heart rate variability (HRV) is one of the possible reasons of decrease in mean ocular perfusion pressure (MOPP).PurposeTo compare the shift of the HRV parameters in NTG and HTG patients after a cold provocation test (CPT).MethodsMOPP, 24-hour blood pressure and HRV were studied in 30 NTG, 30 HTG patients, and 28 healthy subjects. The cardiovascular fitness assessment was made before and after the CPT. The direction and magnitude of the average group shifts of the HRV parameters after CPT were assessed using the method of comparing regression lines in order to reveal the difference between the groups.ResultsMOPP and minimum daily diastolic blood pressure were decreased in HTG and NTG patients compared to healthy subjects. There was no difference in MOPP between HTG and NTG before the CPT. However, all HRV parameters reflected the predominance of sympathetic innervation in glaucoma patients compared to healthy subjects (P < 0.05).Before the CPT, the standard deviation of NN intervals (SDNN) of HRV was lower in HTG compared to NTG, 27.2 ± 4.1 ms and 35.33 ± 2.43 ms (P = 0.02), respectively. After the CPT, SDNN decreased in NTG by 1.7 ms and increased in HTG and healthy subjects by 5.0 ms and 7.09 ms, respectively (P < 0.05). The analysis of relative shift of other HRV parameters after the CPT also revealed a significant difference between NTG and HTG in regard to the predominance of sympathetic innervation in NTG compared to HTG.ConclusionPatients with NTG have more pronounced disturbance of autonomic nervous system than HTG patients, which is manifested with the activation of sympathetic nervous system in response to CPT. This finding refers to the NTG pathogenesis and suggests the use of HRV assessment in glaucoma diagnosis and monitoring.

Residual vision activation and the brain-eye-vascular triad: Dysregulation, plasticity and restoration in low vision and blindness – a review

“…Hence, how stress affects the eye, optic nerve, and brain is an issue that should not to be ignored. On the one hand, the changes of beat-to-beat variations of the heart indicate an involvement of the autonomic nervous system ( Kurysheva, Ryabova & Shlapak, 2018 ) and explain the response of the densely innervated retroocular vessels and the choroid to stress. On the other hand, vessels in and around the optic nerve become constricted by vasoconstrictors such as angiotensin II, endothelin, or adrenalin which reduce blood flow during emotional excitement ( Sossi & Anderson, 1983 ).…”

Autonomic Dysfunction and Blood Pressure in Glaucoma Patients: The Lifelines Cohort Study

“…Studies speculate that autonomic dysfunction affects the susceptibility of the optic nerve to BP changes and is most prominent in normal-tension glaucoma (NTG), a glaucoma subtype where the most important risk factor, an elevated IOP, is lacking. 16 , 17 Autonomic dysfunction involvement in glaucoma pathogenesis is further supported by a cold provocation test, where glaucomatous individuals had greater sympathetic innervation. 17 …”

Associations between the red blood cell distribution width and primary angle-closure glaucoma: a potential for disease prediction

“…A-scan ultrasound biometry (Ultrasonic, Exton, PA, USA) was used to measure the axial length, anterior chamber depth and central corneal thickness. In addition, each study subject underwent a medical examination, including liver function, renal function, blood pressure, heart rate [18] and body temperature assessments. The demographic information of each study subject was also collected, including the age, gender, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), diabetes mellitus history and hypertension history.…”