Thoratec (NSDQ:THOR) initiated a voluntary "correction" for some shipments of its HeartMate II heart pump over concerns that a portion of its outflow conduit could become detached.
The Pleasanton, Calif.-based medical device maker sent the correction out Feb. 23, according to the FDA, warning that it had received reports that less than 1% of the 3,200 devices’ sealed outflow graft bend reliefs were not properly connected. The bend relief is designed to prevent the outflow conduit connecting the pump to the aorta from kinking.
"The reported incidence of the defect, disconnected outflow graft bend relief, is 0.91% (29/3,200). Of these 29 incidents, 24 were observed in x-ray images or during surgical procedures, and were thus unlikely to be related to patient symptoms," according to the federal watchdog agency. "However, in at least 1 reported case, it is noted that the disconnected bend relief may have contributed to the need for reoperation."
Detached bend reliefs can cause low pump flow, hemolysis, fluctuations in pump flow, speed and/or power, or worsening symptoms of heart failure, according to the FDA.
"The incidence of surgical interventions possibly related to disconnected outflow graft bend reliefs is 0.16% (5/3,200). Four of 5 five patients continue on VAD support, and 1 of these 5 died of multi-organ failure after several days of ECMO support; however, it is important to note that it is not clear that the disconnected outflow graft bend relief caused or contributed to this patient’s condition. It is also possible for bleeding to occur, if the disconnected bend relief causes abrasion of the graft [which] required repair in 3 patients. The incidence of bleeding related to abrasion or cutting of the graft is 0.10% (3/3,200)."
Thoratec has advised surgeons on revised procedures for securing the bend relief to the outflow graft, according to the agency, and is advising them to "consider the possibility of a disconnected outflow graft bend relief" if a patient exhibits any of the symptoms associated with the problem.
Potentially problematic HeartMate II devices, including all serial numbers with catalog nos. 104692, 103393, 104911 or 104912, were shipped to 226 hospitals in the U.S., Canada, Europe and elsewhere.
"Since initiating the medical device correction notification on February 23, 2012, the company has contacted all hospitals to whom sealed outflow grafts have been distributed. Subsequently, the company has received signed acknowledgement forms from surgeons at all affected U.S. hospitals and the majority of affected international customers, verifying that customers have reviewed the notification and understand the information provided. Thoratec is not requesting that any product be returned to the company," according to the FDA.