ORTHOSTATIC INTOLERANCE IN AUTONOMIC NEUROPATHIES &POSTURAL TACHYCARDIA SYNDROME

Project: Research project

Project Details

Description

The pathogenesis and management of neurogenic orthostatic hypotension and
the postural tachycardia syndrome (POTS) are poorly understood. Recent
studies suggest that POTS is heterogenous and that a number of mechanisms
might be operative. These include gender-specificity of orthostatic
intolerance, a restricted autonomic neuropathy, hypovolemia, venous
pooling, alpha- and beta-receptor abnormalities and alterations in
brainstem mechanisms, including perturbed central baroreflex regulation.
We will undertake a detailed comparative study of POTS with the well-
defined progressive autonomic disorders (multiple system atrophy [MSA},
pure autonomic failure (PAF} and the autonomic neuropathies). The research
studies will consist of comprehensive clinical and laboratory autonomic
studies using questionnaires, non-invasive techniques of Finapres and
impedance plethysmography, infusions of vasoactive agents to evaluate
alpha- and beta-receptor sensitivity and baroreflex again, and power
spectral analysis, designed in such a way to better define the underlying
mechanisms of orthostatic intolerance. We have accumulated a large cohort
of patients with POTS and will be able to define its natural history.
Insights gained from these studies will be used to improve the management
of POTS, including the acute laboratory administration of agents that can
provide mechanistic insights and have therapeutic potential. The efficacy
of physical countermaneuvers to improve orthostatic tolerance in POTS will
be evaluated. We will determine whether the orthostatic intolerance of
normal women and those with POTS are dependent on the phase of the
menstrual cycle and will attempt to determine whether central regulation of
autonomic function is impaired in POTS.
StatusFinished
Effective start/end date9/15/837/31/10

ASJC

  • Medicine(all)
  • Neuroscience(all)