MAUDE Adverse Event Report: ON-X LIFE TECHNOLOGIES, INC. ON-X MITRAL PROSTHESIS; HEART-VALVE, MECHANICAL

Model Number ONXM-25

Device Problems Activation, Positioning or Separation Problem (2906); Adverse Event Without Identified Device or Use Problem (2993)

Patient Problem Thrombus (2101)

Event Date 08/20/2018

Event Type  Injury  

Manufacturer Narrative

This investigation is currently ongoing.Any additional information will be provided in the follow-up report.

Event Description

According to the initial report, a female patient with high output cardiomyopathy (hocm) had an onxm 25 valve explanted approximately 15 days after initial implantation due to issues with clotting and the leaflets not opening properly.The on-x mitral valve was explanted on (b)(6) 2018 and replaced with a 27 mm tissue valve.According the surgeon's report, the patient presented with high output cardiomyopathy (hocm).The mitral valve was excised with all subvalvular app (apparatus) except small fragment of p1 (papillary muscle).Pledgeted with 2-0 ethibond on ventricular aspect.Twenty-five (25) mm onx.Off coronary pulmonary bypass and transoesophageal echocardiogram (toe).Check echo stuck insufficient leaflet? clot.Inr 2.1-2.3 with 80 mg bd clexane.Iv heparin.Patient taken to theatre (operating room).Stuck insufficient leaflet.Small 3 mm head of papillary muscle in apparatus.Pivot joint with clot/thrombus.Twenty-seven (27) mm tissue valve implanted.Patent extubated well.

Manufacturer Narrative

The valve was returned to the manufacturer for examination.The examination indicated thrombotic formation in the pivot regions of one of the leaflets, which would restrict movement even if native tissue did not.Therefore, with one leaflet restricted in motion, the pressure gradient across the valve would be abnormally high and the flow dynamics similarly affected as noticed on the tee.The historical rate of valvular thrombosis for a rigid heart valve case is 0.8% per patient-year [iso 5840:2005].In three publications of experience with the on-x mitral valve, there were no reported cases of early thrombosis, so this is a rare event [chambers 2013, mcnicholas 2006, palatianos 2001].The manufacturing records for the onxm-25, sn 6217401 were reviewed and it was confirmed that all records were controlled, available for review, and met all specifications per the device master record.All lots passed functional testing and met release specifications.A review of the available information was performed.There appears to be two issues with this case.The first is restricted leaflet motion due to native tissue interference, which would be classified as prosthesis nonstructural dysfunction.The second is prosthesis thrombus due to insufficient anticoagulation (the standard-of-care for mechanical mitral valves is an inr of 2.5-3.0).Both of these events are early events (less than 30 days postop) recognized in the instructions for use (ifu) as potential complications as are the possibilities of reoperation and explantation.The root cause is nonstructural dysfunction due to tissue interference and valve thrombus formation due to inadequate anticoagulation.This event does not identify additional hazards or modify the probability and severity of existing hazards.This report is being submitted as required by federal regulations and does not constitute an admission that the device caused or contributed to the reported event.Furthermore, this report reflects the event as alleged by the complainant and does not imply that the information reported to cryolife is accurate or has been confirmed by cryolife.

Event Description

According to the initial report, one of the most experienced leading surgeons implanted an onxm-25 in a female patient and there has been an issue with clotting, the leaflets not opening properly and the valve has had to be removed and replaced for a tissue valve on august 20.Surgeon thinks that some infarcted papillary muscle tissue appears to have fallen into the leaflet the leaflets were not working properly, there were two clots the patient was on heparin and warfarin, but the surgeon mentioned that they could never get her to a high enough inr.According the surgeon's report, the patient presented with high output cardiomyopathy (hocm).The mitral valve was excised with all subvalvular app (apparatus) except small fragment of p1 (papillary muscle).Pledgeted with 2-0 ethibond on ventricular aspect.25mm onx.Off coronary pulmonary bypass and transoesophageal echocardiogeam (toe).Check echo stuck insufficient leaflet? clot.Inr 2.1-2.3 with 80mg bd clexane.Iv heparin.Patient taken to theatre (operating room).Stuck insufficient leaflet.Small 3mm head of papillary muscle in apparatus.Pivot joint with clot/thrombus.27mm tissue valve implanted.Patent extubated well.

• Brand Name: ON-X MITRAL PROSTHESIS
• Type of Device: HEART-VALVE, MECHANICAL
• Manufacturer (Section D): ON-X LIFE TECHNOLOGIES, INC.; 1300 e. anderson ln., bldg. b; austin TX 78752
• MDR Report Key: 7884973
• MDR Text Key: 120539246
• Report Number: 1649833-2018-00150
• Device Sequence Number: 1
• Product Code: LWQ
• Combination Product (y/n): N
• PMA/PMN Number: P000037
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: company representative,foreig
• Type of Report: Initial,Followup
• Report Date: 11/12/2018

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 09/18/2018
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Device Operator: Health Professional
• Device Model Number: ONXM-25
• Device Catalogue Number: UNKNOWN
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 09/28/2018
• Date Manufacturer Received: 08/22/2018
• Is This a Reprocessed and Reused Single-Use Device?: No
• Patient Sequence Number: 1
• Treatment: 80MG BD CLEXANEHEPARIN IV (INTRAVENOUS); IV HEPARIN80 MG OF CLEXANE TWICE A DAY; IV HEPARIN80 MG OF CLEXANE TWICE A DAY
• Patient Outcome(s): Other; Required Intervention
• Patient Age: 69 YR