MAUDE Adverse Event Report: BOSTON SCIENTIFIC CORP. BOSTON SCIENTIFIC DYNAGEN ICD D153; IMPLANTABLE CARDIOVERTER DEFIBRILLATOR NON- (RT)

Model Number DYNAGEN ICD D153

Device Problems Under-Sensing (1661); Failure to Deliver (2338); Device Sensing Problem (2917)

Patient Problem Patient Problem/Medical Problem (2688)

Event Date 04/29/2019

Event Type  Injury  

Event Description

The pt presented for a generator replacement of the dual chamber implantable cardio-defibrillator (icd), which was implanted 10 yrs earlier for secondary prevention of idiopathic ventricular fibrillation (vf), as the device had reached its elective replacement indicator (er).The device was a boston scientific teligen 100 (e110) attached to boston scientific leads (fineline ii sterox ez 4470 in the right atrium and endotak reliance g 0185 in the right ventricle).The rv/icd lead was an integrated bipolar model (the sensing bipole was the tip electrode to the rv coil).The measured r-wave during sinus rhythm (sr) was borderline (3.5 - 5.5mv) during intra-operative testing (though was >5 mv during prior device clinic interrogations).In view of this, we elected to perform defibrillation threshold (dft) testing to assess adequacy of vf sensing after connection of a new boston scientific generator (dynagen icd d153, sn # (b)(4)).All other lead parameters were stable and within normal range.We performed the 1st test at least sensitivity (1.5 mv) with nominal detection in the vf zone (1 s, 230 bpm), vf was induced with 1.1.1 j shock on t-wave.There was gross undersensing of vf with failure of the device to meet vf detection criteria and therefore for vf were not initiated.The pt required an external residue shock to restore sr.We repeated the test at higher sensitivity (1.0 mv), again with nominal detection settings.Following vf induction, there was still significant undersensing although vf was eventually detected (albeit very delayed).However, charge diversion occurred due to continued undersensing and the shock was aborted.Eventually, vf was re-detected resulting in a committed 21j shock, which failed to defibrillate vf.Thereafter, there was gross undersensing of continued vf and failure to re-detect, such that another rescue shock was required.Ultimately, we replaced the boston scientific icd generator with a medtronic icd generator (evera mri ddmb1d1, serial number #(b)(4)) which also demonstrating some undersensing during vf, but was ultimately successful in detecting and defibrillator vf at minimal sensitivity (1.2 mv) and with prolonged detection intervals.Although the system functioned adequately with the medtronic generator, we felt the performance of the boston scientific rv lead was borderline and the pt underwent elective lead extraction and reimplantation of a new medtronic dual chamber icd system 5 months later.The medtronic rv lead model was a dedicated bipolar model (6935m, serial #(b)(4)).During repair defibrillation testing, there was excellent sensing of vf with no dropouts and successful defibrillation to sinus rhythm.We finally received a report back from boston scientific in february 2020 regarding the concerning performance with vf undersensing in their dynagen icd model.The report essentially summarized that the generator was performing within expectations and the reason for undersensing was due to the fine low amplitude electrograms whilst in vf.As the medtronic device was still able to detect such signals at similar sensitivity levels, we have concerns that specific detection algorithms / filtering of the boston scientific model explains its underperformance.This was potentially life threatening - if the pt developed vf clinically and the device undersensed it and failed the deliver therapy, it would have resulted in a fatality.Fda safety report id# (b)(4).

• Brand Name: BOSTON SCIENTIFIC DYNAGEN ICD D153
• Type of Device: IMPLANTABLE CARDIOVERTER DEFIBRILLATOR NON- (RT)
• Manufacturer (Section D): BOSTON SCIENTIFIC CORP.
• MDR Report Key: 9785723
• MDR Text Key: 182366585
• Report Number: MW5093494
• Device Sequence Number: 1
• Product Code: LWS
• Combination Product (y/n): N
• Reporter Country Code: US
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Voluntary
• Reporter Occupation: Physician
• Type of Report: Initial
• Report Date: 03/01/2020
• 2 Devices were Involved in the Event: 1 2

1 Patient was Involved in the Event

• Date FDA Received: 03/03/2020
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Model Number: DYNAGEN ICD D153
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 04/29/2019
• Is the Reporter a Health Professional?: Yes
• Was Device Evaluated by Manufacturer?: No Information
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: N
• Patient Sequence Number: 1
• Patient Outcome(s): Life Threatening; Other
• Patient Weight: 63