Clinical Trial Details
— Status: Withdrawn
Administrative data
| NCT number |
NCT05829200 |
| Other study ID # |
TCD8675309 |
| Secondary ID |
|
| Status |
Withdrawn |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
July 15, 2013 |
| Est. completion date |
August 2013 |
Study information
| Verified date |
April 2023 |
| Source |
Ochsner Health System |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
Carotid Disease causes 10% of strokes. The Investigators are attempting to investigate the
use of Transcranial Doppler to see if this is and effective, efficient, and/or valid way to
identify individuals at highest risk for thromboembolic events from carotid disease. The plan
is to plot the number of high intensity transient transcranial doppler signals with the
category of patient (asymptomatic, symptomatic, and actively symptomatic) and evaluate if a
relationship exists. The Investigators hypothesize that a linear relationship exists in that
the higher the number of HITS the more symptomatic the patient. If results demonstrate the
numbers of HITS correlate with the severity of disease this could potentially identify
asymptomatic patients having subclinical symptoms who would benefit from a more urgent
surgical intervention versus the current standard of care of elective intervention.
Description:
Approximately 20% of strokes are attributable to carotid stenosis through atheroembolic
events. Ischemic stroke confers a significant morbidity and mortality. Operative intervention
(carotid endarterectomy [CEA]) has proven to decrease the risk of ischemic stroke. The
guidelines for patient selection for carotid surgical intervention were established in the
1990s and have proven reasonably adequate, however with improving technology there may be
modalities that can identify patients that may be at a higher risk than initially thought.
One such modality that is under investigation is the use of transcranial doppler (TCD).
Presently, TCD is primarily used in conjunction with neuro-interventionalist related
procedures (cerebral angiogram/stenting/coiling) to monitor for vasospasm and blood flow
within the cerebral circulation. The technology assessment report of the American Academy of
Neurology published in 1990 stated that TCD has established value in the assessment of
patients with intracranial stenosis, collaterals, subarachnoid hemorrhage, and brain death.
TCD has been used during intraoperative carotid endarterectomy to evaluate blood flow and
need for arterial shunting. Recently, it has been used to identify and detect microemboli via
the evaluation of high intensity transient signals (HITS). It has been shown in asymptomatic
carotid patients that aggressive medical management can decrease the number of HITS on TCD
potentially conferring a decrease in stroke. There is more literature evolving that
demonstrates the potential of TCD being used to assist in patient selection for surgical
intervention (carotid endarterectomy); however the studies have not yet been conducted. Our
study is the first step in beginning this process.
The current standard of care is to consider surgical intervention for the following three
groups of patients with carotid stenosis (a narrowing of the internal carotid artery):
asymptomatic patients are defined as patients who have not experienced a transient ischemic
attack (TIA) and/or stroke-like symptoms who have been identified as having a high grade
carotid stenosis (narrowing of the internal carotid artery of greater than 80% via CTA,
Carotid Doppler Ultrasound, and/or MRA); symptomatic patients who have previously experienced
a ischemic stroke or TIA (no active symptoms at the time of presentation) and have 50% or
greater carotid stenosis diagnosed by the same imaging modalities; the third group are
individuals who present to the hospital as their ischemic symptoms have recently or are
actively occurring with 50% or greater stenosis, unfavorable plaque, and/or acute carotid
occlusion (diagnosed by the same imaging modalities). Our study proposes that the
aforementioned patients undergo TCD to evaluate the number of HITS prior to surgical
intervention.
TCD is a non-invasive study. It does not involve injection of any contrast material or the
need for blood work prior to its undertaking. The test itself takes 30-60 minutes. The test
would be administered by one specifically trained ultrasound technician. The TCD information
will not affect patient care in any way; no definitive treatment will be delayed. The number
of HITS would not change the type or timing of surgical intervention.
This is a prospective study. The first two groups of patients are generally referred to
Ochsner's vascular surgeons and if eligible for surgical intervention during a clinic visit
would be electively referred to get the non-invasive TCD test. There are some individuals in
the second group who may have been admitted to the hospital and their symptoms have resolved.
This group would be identified by neurology and radiology members of the stroke team via
consult to the vascular surgery service. The TCD could be done while the patient was
hospitalized. The third group is identified during a stroke code process. If the patient is
found to meet surgical criteria the patient would undergo TCD in the emergency department or
on the floors upon admission. The TCD order would be initiated by the stroke code team or
vascular surgery.
The TCD reports would be forwarded to and kept by the study coordinator.
The plan would then be to plot the number of HITS with the category of patient (asymptomatic,
symptomatic, and actively symptomatic) and evaluate if a relationship exists. The
Investigators hypothesize that a linear relationship exists in that the higher the number of
HITS the more symptomatic the patient. If results demonstrate the numbers of HITS correlate
with the severity of disease this could potentially identify asymptomatic patients having
subclinical symptoms who would benefit from a more urgent surgical intervention versus the
current standard of care of elective intervention.
