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

Relevance: Vascular 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).

Purpose: To compare the shift of the HRV parameters in NTG and HTG patients after a cold provocation test (CPT).

Heart rate variability in normal tension glaucoma: A case-control study.

Primary vascular dysregulation (PVD) is believed to be a main cause of local vasospasm and impaired autoregulation as a possible contributing factor in the pathogenesis of normal tension glaucoma (NTG). Subjects with PVD respond stronger to psychological stress. Autonomic dysfunction is another reason of instable ocular blood flow and may be studied by means of assessment of heart rate variability (HRV) especially during a hand-cold provocation test (CPT).