St. Jude Defends Riata Defibrillator Lead, But Expert SkepticalNov 13, 2007 | Parker Waichman LLP
St. Jude Medical Inc. is trying to undo the damage caused by reports that its Riata Defibrillator Lead wires have perforated the hearts of some patients. The company claims that reports that the St. Jude Riata Defibrillator Lead wire is more prone to cause heart perforations are overstated, and that its own data shows the Riata Lead is safe. However, at least one heart expert has disputed St. Jude’s contention, telling the Wall Street Journal that the company’s data could be misleading since physicians don’t always report instances of heart perforations from defibrillator lead wires.
An article published online yesterday by the medical journal “Pace” detailed four instances where St. Jude Riata Defibrillator Leads detached and poked holes through the heart wall. In one of those instances, the St. Jude Riata Defibrillator Lead came within just 7 millimeters of poking through a patient’s skin. In an editorial accompanying the “Pace” article, Dr. Stephen Vlay, a cardiologist for Stony Brook University in New York, wrote that the problems with the St. Jude Riata Defibrillator Leads could be due to an “inherent design flaw, at least in some models of the Riata lead.”
A defibrillator lead is a thin wire that attaches an implantable defibrillator to the heart. When a defibrillator lead wire detaches, it can poke a hole through the heart wall. If this happens the heart can bleed into the pericardial sac around it, leading to a lethal condition called cardiac tamponade. While such malfunctions can happen with any defibrillator lead, evidence is emerging that such detachment and perforation is occurring more frequently than expected with the St. Jude Riata Defibrillator Leads.
The “Pace” article is not the first to detail detachment and perforation problems with the St. Jude Riata Defibrillator Lead. Earlier this year, the medical journal “Heart Rhythm” reported that the St. Jude Riata Defibrillator Lead had a higher perforation rate than what had been stated by the manufacturer. According to that article, doctors at Massachusetts General Hospital reported a perforation rate of 3.8% - or 5 out of 130 – for the St. Jude Riata Defibrillator Lead. Doctors from New York Hospital Queens also reported to “Heart Rhythm” that of 59 St. Jude Riata Defibrillator Leads implanted there, five had perforated. New York Hospital Queens has since stopped using the defective St. Jude Riata Defibrillator Lead.
St. Jude, however, disputes those numbers, and yesterday it published a response to Dr. Vlay’s editorial in “Pace”. The article includes data from the company's returned product analysis and new information showing that the St. Jude Defibrillator Lead wire’s incidence rate of perforation is below or at the low end of what has been reported. St. Jude also asserted that perforation problems with the Riata Defibrillator leads could be attributed to a “combination of factors including patient characteristics, the design characteristics of the lead and implant techniques”.
Yesterday, however, Dr. Vlay told the Wall Street Journal that St. Jude’s figures on the Riata Lead’s perforation rate have not convinced him that the component is safe. For one thing, Dr. Vlay pointed out that physicians do not always report incidents of detachment and perforations to lead manufacturers. For that reason, St. Jude’s data is likely skewered lower, he said.
Medical device manufacturers don’t always have accurate figures regarding failures. In October, Medtronic Inc. recalled its Sprint Fidelis Defibrillator Lead over a fracturing problem. Month’s prior, the Minneapolis Heart Institute had informed Medtronic that the Sprint Fidelis Lead had a higher-than-normal fracture rate. At the time, Medtronic insisted that its own data indicated no such problems. But following a new analysis of its data, Medtronic ultimately pulled the Sprint Fidelis Lead from the market in October.