Manufacturer's investigation conclusion: elevated power and flow events were confirmed in the evaluation of the submitted controller event log file; however, a specific cause for the events cannot be determined through this evaluation.A specific cause for the reported grinding noise coming from the pump could not conclusively be determined through this evaluation.The submitted log file contained data from (b)(6) 2020 14:53:05 through (b)(6) 2020 00:29:17.Two elevated power events of 9.1 and 11.4 watts were captured on (b)(6) 2020, and estimated flow reached 11.0 and 12.0 lpm during these events.These events were captured while the patient was supported by battery power.Prior to and after the elevated flow and power events, the pump appeared to function as intended and no other unusual alarms or events were captured.A specific cause for the changes in pump parameters could not be conclusively determined through this evaluation.Per the customer, the patient¿s lvad parameters were being monitored.The grinding had since stopped but continued to monitor.The patient was asymptomatic, stable, and remains on routine care.It was reported through patient product that the patient underwent pump exchange on (b)(6) 2021, hmii (b)(6) to hmii (b)(6).(b)(6) was not returned for evaluation.The patient remains ongoing on heartmate ii 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 lvas kit shipped on 09may2016.The heartmate ii lvas instructions for use (ifu) provides an explanation of each of the pump parameters (including pump power and flow) in sections 1 "introduction" and 4 "system monitor".Section 1 (under "explanation of parameters") explains that device power is a direct measurement of pump motor voltage and current.Changes in pump speed, flow, or physiological demand can affect pump power.Abrupt changes in power should be evaluated for cause.In addition, device flow and power generally retain a linear relationship at a given speed.However, while power is directly measured by the system controller, the reported flow is estimated, based on power.Since the flow displayed on the system controller is a calculated value, it becomes imprecise at the low and high ends of the linear power-flow relationship.Section 4 ¿system monitor¿ cautions that no single parameter is a surrogate for monitoring the clinical status of the patient, and the changes in all parameters should be considered when assessing any clinical situation.Section 4 also addresses pi events as well as potential causes.Section 6 "patient care and management" (under "pump performance monitoring") addresses assessing pump flow and explains that pump performance is sensitive to changes in systemic vascular resistance and left ventricular filling.Heartmate ii lvas patient handbook, is currently available.Section 1 ¿introduction¿ directs the user to call a hospital contact right away ¿if you notice a change in how your pump sounds, feels, or works.Even small changes should be reported.¿ no further information was provided.The manufacturer is closing the file on this event.
|