Manuals Link

VNS (vagus nerve stimulation) Therapy ® is a unique treatment approach now available specifically for treatment-resistant depression. VNS Therapy is indicated for use as an adjunctive long-term treatment of chronic or recurrent depression for patients 18 years of age or older who are experiencing a major depressive episode and have not had an adequate response to four or more adequate antidepressant treatments.

3. CONTRAINDICATIONS _________________
The VNS Therapy System cannot be used in patients after a
bilateral or left cervical vagotomy.

Do not use shortwave diathermy, microwave diathermy or
therapeutic ultrasound diathermy (hereafter referred to as
diathermy) on patients implanted with a VNS Therapy System.

Diagnostic ultrasound is not included in this contraindication.
Energy delivered by diathermy may be concentrated into or
reflected by implanted products such as the VNS Therapy System.
This concentration or reflection of energy may cause heating.

Testing indicates that diathermy can cause heating of the VNS
Therapy System well above temperatures required for tissue
destruction. The heating of the VNS Therapy System resulting from
diathermy can cause temporary or permanent nerve or tissue or
vascular damage. This damage may result in pain or discomfort,
loss of vocal cord function, or even possibly death if there is
damage to blood vessels.

Because diathermy can concentrate or reflect its energy off any sizeimplanted
object, the hazard of heating is possible when any portion
of the VNS Therapy System remains implanted, including just a
small portion of the Lead or electrode. Injury or damage can occur
during diathermy treatment whether the VNS Therapy System is
turned “ON” or “OFF”.

Diathermy is further prohibited because it may also damage the
VNS Therapy System components resulting in loss of therapy,
requiring additional surgery for system explantation and
replacement. All risks associated with surgery or loss of therapy
(loss of seizure control) would then be applicable.

Advise your patients to inform all their health care professionals
that they should not be exposed to diathermy treatment.



4. WARNINGS ________________________
Physicians should inform patients about all potential risks and adverse
events discussed in the VNS Therapy System physician’s manuals.
Use (depression)—

This device is a permanent implant. It is only to be used in patients
with severe depression who are unresponsive to standard psychiatric
management. It should only be prescribed and monitored by
physicians who have specific training and expertise in the
management of treatment-resistant depression and the use of this
device. It should only be implanted by physicians who are trained in
surgery of the carotid sheath and have received specific training in
the implantation of this device.

Not curative (depression)—Physicians should warn patients that
VNS Therapy has not been determined to be a cure for depression.
Patients should be counseled to understand that individual results
will likely vary. Beneficial results might not become evident for
months. Most patients will continue to require antidepressant
medications and/or electroconvulsive therapy (ECT) in addition to
VNS Therapy.

Unapproved uses—The safety and efficacy of the VNS Therapy
System have not been established for uses outside the “Intended
Use / Indications” section of this multi-part physician’s manual,
including (but not limited to) patients with:
�� Acute suicidal thinking or behavior (depression)
�� History of schizophrenia, schizoaffective disorder or
delusional disorders (depression)
�� History of rapid cycling bipolar disorder (depression)
�� History of previous therapeutic brain surgery or CNS injury
Cyberonics 26-0006-4100/2 (U.S.) — 9 of 20
Introduction to the VNS Therapy™ System
�� Progressive neurological diseases other than epilepsy or
depression
�� Cardiac arrhythmias or other abnormalities
�� History of dysautonomias
�� History of respiratory diseases or disorders, including dyspnea
and asthma
�� History of ulcers (gastric, duodenal, or other)
�� History of vasovagal syncope
�� Only one vagus nerve
�� Other concurrent forms of brain stimulation
�� Pre-existing hoarseness
�� Under 12 years of age (epilepsy)
�� Under 18 years of age (depression)
�� Primary generalized seizures

Worsening depression/suicidality (depression)—Patients being
treated with adjunctive VNS Therapy should be observed closely
for clinical worsening and suicidality, especially at the time of VNS
Therapy stimulation parameter changes or drug or drug dose
changes, including either increases or decreases in the stimulation
parameters or concomitant treatments. Consideration should be
given to changing the therapeutic regimen of VNS Therapy or
concomitant treatments, including possibly discontinuing VNS
Therapy or the concomitant therapy, in patients whose depression is
persistently worse or whose emergent suicidality is severe, abrupt in
onset, or was not part of the patient’s presenting symptoms.

Dysfunctional cardiac conduction systems—The safety and
effectiveness of the VNS Therapy System in patients with
predisposed dysfunction of cardiac conduction systems (re-entry
pathway) have not been established. Evaluation by a cardiologist is
recommended if the family history, patient history, or
electrocardiogram suggests an abnormal cardiac conduction
pathway. Serum electrolytes, magnesium, and calcium should be
documented before implantation. Additionally, postoperative
bradycardia can occur among patients with certain underlying
cardiac arrhythmias. Post-implant electrocardiograms and Holter
monitoring are recommended if clinically indicated.

It is important to follow recommended implantation procedures and
intraoperative product testing described in the Implantation and
Follow-up part of this multi-part physician’s manual. During the
intraoperative System Diagnostics (Lead Test), infrequent incidents
of bradycardia and/or asystole have occurred. If asystole, severe
bradycardia (heart rate < 40 bpm), or a clinically significant change
in heart rate is encountered during a System Diagnostics (Lead Test)
or during initiation of stimulation, physicians should be prepared to
follow guidelines consistent with Advanced Cardiac Life Support
(ACLS).

Additionally, postoperative bradycardia can occur among patients
with certain underlying cardiac arrhythmias. If a patient has
experienced asystole, severe bradycardia (heart rate < 40 bpm) or a
clinically significant change in heart rate during a System
Diagnostics (Lead Test) at the time of initial device implantation, the
patient should be placed on a cardiac monitor during initiation of
stimulation.

The safety of this therapy has not been systematically established for
patients experiencing bradycardia or asystole during VNS Therapy
System implantation.

Swallowing difficulties—Difficulty swallowing (dysphagia) may
occur with active stimulation, and aspiration may result from the
increased swallowing difficulties. Patients with pre-existing
swallowing difficulties are at greater risk for aspiration. Appropriate
aspiration precautions should be taken for such patients.

Dyspnea or shortness of breath—Dyspnea (shortness of breath)
may occur with active VNS Therapy. Any patient with underlying
pulmonary disease or insufficiency such as chronic obstructive
pulmonary disease or asthma may be at increased risk for dyspnea
and should have their respiratory status evaluated prior to
implantation and monitored following initiation of stimulation.

Obstructive sleep apnea—Patients with obstructive sleep apnea
(OSA) may have an increase in apneic events during stimulation.
Lowering stimulus frequency or prolonging “OFF” time may
prevent exacerbation of OSA. Vagus nerve stimulation may also
cause new onset sleep apnea in patients who have not previously
been diagnosed with this disorder. It is recommended that patients
being considered for VNS Therapy who demonstrate signs or
symptoms of OSA, or who are at increased risk for developing
OSA, should undergo the appropriate evaluation(s) prior to
implantation.

Device malfunction—Device malfunction could cause painful
stimulation or direct current stimulation. Either event could cause
nerve damage and other associated problems. Patients should be
instructed to use the Magnet to stop stimulation if they suspect a
malfunction, and then to contact their physician immediately for
further evaluation. Prompt surgical intervention may be required if a

MRI—Patients with the VNS Therapy System or any part of the
VNS Therapy System implanted should not have full body MRI.
Additional surgery may be required to remove the VNS Therapy
system if full body MRI is required.

Note: Use of the Magnet to activate stimulation is not recommended for
patients with depression. The Magnet Mode output current should remain
at 0.0mA for patients with depression.

Excessive stimulation—Excessive stimulation at an excess duty
cycle (that is, one that occurs when “ON” time is greater than
“OFF” time) has resulted in degenerative nerve damage in
laboratory animals. An excess duty cycle can be produced by
continuous or frequent magnet activation (> 8 hours), as determined
by animal studies. Do not stimulate at these combinations of ranges.

Device manipulation—Patients who manipulate the Pulse
Generator and Lead through the skin (Twiddler’s Syndrome) may
damage or disconnect the Lead from the Pulse Generator and/or
possibly cause damage to the vagus nerve. Patients should be
warned against manipulating the Pulse Generator and Lead.

Sudden unexplained death in epilepsy (SUDEP): Through
August 1996, 10 sudden and unexplained deaths (definite, probable,
and possible) were recorded among the 1,000 patients implanted
and treated with the VNS Therapy device. During this period, these
patients had accumulated 2,017 patient-years of exposure.
Some of these deaths could represent seizure-related deaths in
which the seizure was not observed, at night, for example. This
number represents an incidence of 5.0 definite, probable, and
possible SUDEP deaths per 1,000 patient-years.

Athough this rate exceeds that expected in a healthy (nonepileptic)
population matched for age and sex, it is within the range of
estimates for epilepsy patients not receiving vagus nerve
stimulation, ranging from 1.3 SUDEP deaths for the general
population of patients with epilepsy, to 3.5 (for definite and
probable) for a recently studied antiepileptic drug (AED) clinical
trial population similar to the VNS Therapy System clinical cohort,
to 9.3 for patients with medically intractable epilepsy who were
epilepsy surgery candidates.

MANUALS