St. Jude Medical, Inc. Silzone Heart Valve Litigation

What is Silzone™ ?

St. Jude Medical trademark for a silver coating process that was used to treat heart valve prosthesis sewing cuffs.

The concept was that the silver on the cuff would act as a local antimicrobial agent, which would lead to a lower incidence of prosthetic valve endocarditis, a rare, but often fatal complication of heart valve surgery.

The Products at Issue

» St. Jude Master Series heart valves with Silzone™ Heart valves
» In Canada and EU countries, the Regent™ and EPIC™ valves also prior to January 2001 had Silzone™ .
» SJM Tailor™ Annuloplasty Rings with Silzone™ coating
» SJM Sequin™ Annuloplasty Rings with Silzone™coating

What is the concern here?

Starting in July, 1997, St Jude introduced Silzone™ coated heart valve prosthetic products in Canada, Europe and the UK. Starting in June 1998 it introduced a number of these products in the U.S. and Australia.

On January 21, 2000, St. Jude initiated a voluntary worldwide recall of all field inventory of heart valve replacement and repair products incorporating its proprietary Silzone™ coating on the sewing cuff fabric.

What is the concern?

Silzone™ taken off market following reports of:

» Higher rate of paravalvalar leakage in Silzone™ Master Series valves compared to non Silzone product.
» Higher rate of thromboembolic events (strokes, heart attacks, TIA’s) in the Silzone valves compared to similar non-Silzone product.
» Improper healing tissue growth (e.g.- too much; not enough; tissue friable; heart annulus appeared eaten away).

» 36,000 people worldwide were implanted with defective Silzone™ coated heart valves.
» 10,500 in the United States.
» 2,500 in Canada.
» 23,000 in Europe and U.K.

What went wrong?

» Inadequate research and testing of the silver coating prior to marketing.
» No meaningful clinical study on safety and efficacy prior to market release.
» Optimistic views taken by SJM of equivocal evidence.
» Key test and experiment results not provided to regulatory bodies.
» Aggressive marketing by SJM’s sales force.
» Co-opting of key opinion and research leaders in the field.

United Kingdom Medical Advisory

Over the last year MDA has received notification that 7 patients suffered a stroke or peripheral embolism among a group of 51 patients implanted with Silzone® heart valves by a number of surgeons at one UK centre. Six of these patients had received a mitral Silzone® valve (including one who had received both mitral and aortic valves). The adverse events occurred within 3 months of valve implantation, and in two cases extensive thrombus was identified on the valve's silver coated sewing cuff. There have been a further 5 suspected incidents of TIA among this patient group.

Immediate Action:
» Follow up all patients implanted with Silzone® mechanical heart valves to identify any signs of stroke or transient ischemic attack (TIA) and ensure adequate anticoagulation control.
» Consider examining patients using Trans-Oesophageal Echocardiography (TOE) to identify any signs of valve thrombus….

In addition a pathologist outside the UK [Canada] has reported concerns based upon his evaluation of an unexpectedly high number of Silzone® valve explants.

The Avert Study

» Artificial Valve Endocarditis Reduction Trial
» Sponsored by SJM
» Multi-site – Headquartered in Pittsburgh
» Designed to see if Silzone reduced PVE
» Independent Data and Safety Monitoring Board managing study advised St. Jude on January 21 that further enrollment in the study was suspended due to unacceptable level of explants due to paravalvular leakage in the Silzone "arm" of AVERT.

Were there signals prior to recall? YES!

» Number of Thromboembolic in Cardiff, Wales study commissioned by SJM on Silzone valves reported to St. Jude in October, 1998.
» Toronto Explant experience brought to SJM’s attention in November, 1998.
» Canadian, Belfast and Denmark hospitals stopped Silzone™ implants due to complications.
» Animal studies were indicative of problems.
» Silver coated catheter studies showed there were problems with the coating.

How to tell if you have a Silzone™ product?

» Date of implant should be after July 1997 (June, 1998 in US) and on or before Jan 21, 2000 (See Table)
» Check “pocket card” patient is given
» On mechanical valves look for an “S”in the serial number
Examples: “19AS-601”; “19MS-601”;"19AECS-602"; "21MECS-602";
» Check surgical or operative report records

Current Litigation

Federal cases across the nation are assigned to MDL No. 1396 in Minnesota. These cases are being managed by Judge Tunheim. State cases are centered in Ramsey County (St. Paul) Minnesota. These cases are being managed by Judge Gearin. Cases are also pending in Texas and Nevada.