It was reported that the patient had been having intermitted low flow hazard alarms.The patient underwent an echocardiogram (echo), electrocardiogram (ekg), and labs.The alarms have not resolved.Log files confirmed low flow alarms.Heparin was initiated due to concerns for a possible thrombus.Milrinone and epinephrine were also started and no change in flow was noted.The speed was lowered to 5000 rotations per minute (rpm) and slowly increased to 6700 rpm with little to no change in flow.A computed tomography angiography (cta) was performed to confirm if there was an outflow graft obstruction.Of note, there was an area at the distal end of the bend relief that was concerning for outflow graft compression.The patient was transferred for further evaluation and possible surgical intervention.
|
Manufacturer's investigation conclusion: the reported outflow graft obstruction could not be confirmed as no clear images were submitted depicting the obstruction.A specific cause for the outflow graft obstruction could not conclusively be determined.Evaluation of the submitted log file revealed that the patient experienced low flow fault flags and low flow hazard alarms.No atypical events or alarms were captured.The pump appeared to function as intended at the set speed.Evaluation of the submitted video of computed tomography angiography (cta) scans was unremarkable.Multiple attempts were made to obtain additional information from the customer regarding the event; however, no additional information was provided.The patient remains ongoing on heartmate 3 left ventricular assist system (lvas), serial number (b)(6).No product is available for investigation.The relevant sections of the device history records for (b)(6) were reviewed and showed no deviations from manufacturing or quality assurance specifications.The heartmate 3 lvas instructions for use (ifu), rev.C and the heartmate 3 lvas patient handbook, rev.D are currently available.Section 1 of the ifu addresses all pump parameters including pump speed, power, flow, and pulsatility index.Section 4 of the ifu, ¿system monitor¿, further addresses the pump parameters and describes situations which may result in a low flow hazard alarm, including changes in patient conditions.Section 6, ¿patient care and management¿, explains that pump performance is sensitive to changes in systemic vascular resistance and left ventricular filling, explains that pump flow is estimated from pump power, and addresses assessing pump flow.Section 5 of the ifu, "surgical procedures", contains information on "preparing the sealed outflow graft" and explains that prior to implantation, the bend relief should be disengaged from the graft for the de-airing procedure.Section 5 also contains a sub-section on "attaching the sealed outflow graft to the aorta", which instructs the user to stretch the graft completely and then measure and cut the sealed outflow graft to the appropriate length.Section 5 of the ifu, under "attaching the sealed outflow graft to the pump", instructs the user to verify that the outflow graft is not twisted or kinked by checking the position of the black line on the graft above and below the bend relief and ensuring that the line is straight.Section 5 of the ifu, under "de-airing the pump", cautions the user: "do not rotate/twist the sealed graft.Check the alignment of the black line on the graft to verify that the sealed graft is not twisted or kinked." this section also explains how to attach the bend relief once the vent needle has been removed from the sealed outflow graft and leaks have been ruled out.This section further warns that failure to connect the bend relief so that it is fully and evenly connected can allow kinking and abrasion of the graft, which may lead to serious adverse events such as low left ventricular assist device flow and/or bleeding.Section 7 of the ifu, ¿alarms and troubleshooting¿, and section 5 of the patient handbook, ¿alarms and troubleshooting¿, describe all alarm conditions, including the low flow hazard alarm, as well as the appropriate actions associated with each condition.No further information was provided.The manufacturer is closing the file on this event.
|
It was reported that the patient underwent a surgical release of the lvad outflow graft compression on (b)(6) 2022, after which the alarms resolved.The patient was taken to the operating room (or), and the or team was prepared for the potential need for cardiopulmonary bypass (cpb).Once the chest was opened, the ofg compression was released and the chest was reclosed without having to go on cpb.The patients flows immediately returned to 4 lpm and their organ function subsequently improved.The patient continued to be monitored and long term anticoagulation was used.
|