MAUDE Adverse Event Report: MEDTRONIC NEUROMODULATION SOLETRA; IMPLANTED SUBCORTICAL ELECTRICAL STIMULATOR (MOTOR DISORDERS)

Model Number 7426

Device Problems Therapy Delivered to Incorrect Body Area (1508); Low impedance (2285); Battery Problem (2885); Device Operates Differently Than Expected (2913)

Patient Problems Muscle Spasm(s) (1966); Undesired Nerve Stimulation (1980); Neurological Deficit/Dysfunction (1982); Device Overstimulation of Tissue (1991); Paresis (1998); Dysphasia (2195)

Event Date 11/27/2015

Event Type  Injury  

Manufacturer Narrative

Please note that this date is based off the date of publication of the article as the actual event date was not provided.Information references the main component of one of the systems involved in the reported events; other applicable components are: product id: 3387, product type: lead.

Event Description

Wolf, m.E., blahak, c., krauss, j.K.The importance of checking impedance: misinterpretation of deep brain stimulation dysfunction as epilepsy.Movement disorders clinical practice.2016; 3(2):206-208.Doi:10.1002/mdc3.12267 summary: dbs of the globus pallidus internus (gpi) has become an accepted treatment for generalized and segmental dystonia.Occasionally, side effects such as dysarthria or visual and gait disturbances have been reported, limiting further voltage increase.However, when respecting thresholds, dbs is generally well tolerated.In less than 1%, serious hardware complications, such as lead fractures, may occur.Reported event: one female patient underwent bilateral globus pallidus internus (gpi) deep brain stimulation (dbs) at the age of 76 for treatment of tardive segmental dystonia.Stereotactic ct demonstrated appropriate placement of dbs electrodes.The patient was regularly followed every two months and experienced sustained benefit with stimulation at 3.2v.After 50 months of chronic and uneventful stimulation, at the age of 80, the patient was admitted to a regional hospital with acute tonic spasms of the right face and arm, severe dysarthria, and mild right-sided hemiparesis, interpreted as focal epileptic status with consecutive todds' hemiparesis.Acute treatment with intravenous phenytoine and levetiracetam resulted in rather little improvement.Logopedic examination revealed difficulties in swallowing requiring adapted alimentation.Acute stroke was ruled out by ct imaging.After 19 days, the patient was discharged with the diagnosis "prolonged focal epileptic status." it presentation in the dbs outpatient clinic the following day, she still complained about dysarthria and impaired fine motor skills of the right arm.When checking implantable neurostimulator (ins) settings, a markedly increased current drain and corresponding drop of therapeutic impedance by 44% were found for the left-sided active electrode contact.Electrode impedance revealed reduced impedances on the two distal contacts (0 and 1).After reducing voltage from 4.6 to 2.4v, symptoms resolved almost completely within minutes.Mri showed correct position of the electrodes.The author stated that this was a spontaneous acute overstimulation the gpi, which mimicked a focal epileptic status.The acute spasms of the right face/arm associated with typical worsening of articulation were the result of a spontaneous current increase at the contralateral electrode contact with capsular stimulation.This was supported by two clinical aspects: first, the deficit did not improve significantly with a potent antiepileptic treatment; second, the reduction of dbs intensity resulted in acute improvement of symptoms within minutes.Neglect of dbs-related complications resulted in a long hospitalization requiring several therapeutic approaches and had a relevant impact on the patient's quality of life.Eleven months after the aforementioned event, the ins device was replaced.The author stated that technical evaluation of the ins by the manufacturer was unremarkable.Impedances of the left lead remained reduced compared to the contralateral side following implant of the new ins.The reduced impedance on the two distal contacts was suggestive of a short circuit, which would explain the capsular side effect by the extended field, including the additional distal functionally active contact.An acute change of tissue conductance nearby the electrode was unlikely after more than four years of chronic dbs.The cause of the acute spontaneous increase of current remained unclear.Asymmetric stimulation intensities were used going forward, permitting balanced effective currents.The patient did well and never reported ictal events or capsular side effects in the 10 years of follow-up.

Manufacturer Narrative

If information is provided in the future, a supplemental report will be issued.

• Brand Name: SOLETRA
• Type of Device: IMPLANTED SUBCORTICAL ELECTRICAL STIMULATOR (MOTOR DISORDERS)
• Manufacturer (Section D): MEDTRONIC NEUROMODULATION; 800 53rd ave ne; minneapolis MN 55421 1200
• Manufacturer (Section G): MEDTRONIC NEUROMODULATION; 800 53rd ave ne; minneapolis MN 55421 1200
• Manufacturer Contact: diane wolf ; 7000 central avenue ne rcw215; minneapolis, MN 55432 ; 7635263987
• MDR Report Key: 5776352
• MDR Text Key: 49022160
• Report Number: 3007566237-2016-02532
• Device Sequence Number: 1
• Product Code: MRU
• Combination Product (y/n): N
• Reporter Country Code: GM
• PMA/PMN Number: H020007
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: foreign,health professional,l
• Reporter Occupation: Health Professional
• Type of Report: Initial,Followup
• Report Date: 07/07/2016

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 07/07/2016
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Model Number: 7426
• Device Catalogue Number: 7426
• Device Lot Number: UNKNOWN
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Date Manufacturer Received: 06/09/2016
• Is the Device Single Use?: Yes
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Initial
• Patient Sequence Number: 1
• Patient Outcome(s): Hospitalization
• Patient Age: 76 YR