Spine Implants May Help Clear Up Orthostatic Hypotension
Electrical implants in the spine can clear up feelings of lightheadedness upon standing — the result of a condition called orthostatic hypotension — in people with neurological disorders like Parkinson’s disease, new research shows.
Orthostatic hypotension refers to a sudden drop in blood pressure when a person moves from lying down to standing up. In its most severe forms, it can lead to severe lightheadedness and dizziness, and may even cause syncope, when a person faints upon standing.
Many people with Parkinson’s disease experience orthostatic hypotension because the neurological circuits that normally help regulate blood pressure are damaged by the disease. Other neurological diseases can also result in this symptom.
Scientists in Switzerland described the case of a 48-year-old woman with multiple-system atrophy, a neurological disorder with many symptoms similar to Parkinson’s. The woman had severe orthostatic hypotension, to the point that she was only able to walk about a dozen feet at a time before having to lie down.
The researchers surgically implanted an electrical device in the woman’s spine. The device, which requires wireless charging, contains an accelerometer that can sense body movements and deliver electrical pulses to the spine in response. The general idea is to replace the neuronal circuitry that normally helps regulate blood pressure.
The report, “Implanted System for Orthostatic Hypotension in Multiple-System Atrophy,” was published in The New England Journal of Medicine.
Once the device was implanted, the researchers conducted tilt-table tests, which involve lying on a table that can be tilted, causing blood pressure changes similar to standing in a controlled environment. When the device was off, the patient’s systolic blood pressure went from 160 mm Hg to 75 mm Hg in less than 3 minutes upon tilting. However, with the device on, tilting resulted in a similar overall decrease in blood pressure, but it was much slower, happening over about 10 minutes.
“The system slowed and delayed the development of hypotension after the patient stood, possibly allowing cerebral autoregulation to accommodate the reduced blood pressure,” the researchers wrote.
The patient underwent three weeks of rehabilitation with the system, and eventually was using the system at home. At that point, she was able to walk 50 meters (about 160 feet) with the use of a walker, and was able to stand and get into bed without assistance.
By three months after surgery, the patient could walk 250 meters (around 820 feet) with a walker while the device was on. At eight months after surgery, she was still using the device every day and was no longer experiencing any syncope.
“She is not cured, she would not run a marathon, but this surgery has clearly improved her quality of life,” Jocelyne Bloch, MD, a neurosurgeon and study co-author from Lausanne University Hospital, said in a news release.