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

Model Number UNKNOWN

Device Problems Gradient Increase (1270); Appropriate Term/Code Not Available (3191)

Patient Problems No Information (3190); No Code Available (3191)

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 email from the distributor,"with on-x mitral valve, non-synchronal open of the leaflet were found with recent 3 mvr(on-x) cases, through echography just after the surgery.The gradient became larger, and some redos and/or additional procedures were done for these cases, however, no defect found on the on-x valves (according to the surgeon).This surgeon has been implanting on-x valve for long (averagely 15 cases with on-x m, and 25 cases with on-x a per a year), and these 3 cases are new and consecutive for him.He is wondering why, and asking us advice or information to avoid.Please provide with relevant literatures or papers related such case to explain, or to get any idea to avoid." this investigation is relegated to the first of three alleged mitral events.

Manufacturer Narrative

Multiple requests for additional information were made without success to acquire the following additional clarifying information: dates of implant, dates of intervention, indication for implant, serial numbers, what was observed upon redo/reintervention, the condition of the native tissue, and whether the valves were available for return evaluation.No additional information was provided.Manufacturing records for the on-x valve used in the case were not reviewed as the serial number was not provided.Shipping records were not queried for the potential serial number of the on-x valve as the date of implant was not provided.A review of the available information was performed.Very sparse information available for review.A surgeon, described as experienced with the on-x valve in both aortic and mitral positions, complained of asynchronous leaflet closing for three consecutive mitral cases, as observed on echocardiogram immediately post-implant.The resulting pressure gradients seemed too high-even though the valves are described by the surgeon as free from defects-which has led the surgeon to redo the surgeries or make other adjustments.The complainant is asking for suggestions as to the cause, if there a procedural change to be made, and any relevant literature or documentation.Barring anatomical interference, a fully functional bileaflet mechanical valve's leaflets will open and close asynchronously if there is an asynchronous blood flow pattern across the leaflets.Leaflet action is passive and entirely dependent upon the fluid motion in which they are immersed.Consequently , the probable cause of the asynchrony has to do with the orientation of the valve with respect to the prevailing hydrodynamic motion.As explained by kilner, et al., fluid flow through the heart is itself asymmetric [kilner, 2000] and anything that alters the normal helical flow through the ventricle will create distorted local flow paths that can, in turn, alter the action of a bileaflet mechanical valve.It is for this reason that the recommendation in the instructions for use (ifu) is for the anti-anatomic orientation of the on-x valve in the mitral position.Whether or not this recommendation was followed, we do not know.Without evidence of anatomic interference or leaflet immobility, the most likely cause of asynchronous leaflet closure is valve orientation.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 email from the distributor,"with on-x mitral valve, non-synchronal open of the leaflet were found with recent 3 mvr(on-x) cases, through echography just after the surgery.The gradient became larger, and some redos and/or additional procedures were done for these cases, however, no defect found on the on-x valves (according to the surgeon).This surgeon has been implanting on-x valve for long (averagely 15 cases with on-x m, and 25 cases with on-x a per a year), and these 3 cases are new and consecutive for him." this investigation is relegated to the first of three alleged mitral events.

• Brand Name: ON-X PROSTHETIC MITRAL VALVE
• Type of Device: HEART-VALVE, MECHANICAL
• Manufacturer (Section D): ON-X LIFE TECHNOLOGIES; 1300 e. anderson ln., bldg. b; austin TX 78752
• MDR Report Key: 7172626
• MDR Text Key: 96674720
• Report Number: 1649833-2018-00096
• 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: distributor,foreign
• Type of Report: Initial,Followup
• Report Date: 04/05/2018

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 01/08/2018
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Device Operator: Physician
• Device Model Number: UNKNOWN
• Was Device Available for Evaluation?: No
• Distributor Facility Aware Date: 12/10/2017
• Date Manufacturer Received: 12/10/2017
• Is This a Reprocessed and Reused Single-Use Device?: No
• Patient Sequence Number: 1
• Patient Outcome(s): Hospitalization; Other