title: Correlation of Pre-Explant Lactate Dehydrogenase Concentrations and Findings During Post-Explant Pump Analysis of the HeartMate II Left Ventricular Assist Device.
abstract: BACKGROUND
  Analyses of the HeartMate II left ventricular assist device are routinely performed after explant if returned to the manufacturer. Findings from manufacturer-reported pump analyses have not been correlated with pre-explant serum lactate dehydrogenase (LDH) values.
  
  
  METHODS
  Between May 2004 and December 2014, 502 patients underwent primary HeartMate II implantation. Seventy pumps were explanted in 58 patients and returned to the manufacturer for pump analysis: 51 (73%) for suspected pump thrombosis, 12 (17%) for device-related infection, and 7 (13%) for percutaneous lead fracture. Median time from implant to explant was 12.4 months (range, 1 to 57 months).
  
  
  RESULTS
  Pump thrombus was confirmed in 53 of 70 pumps (76%). Stratified by major clinical indications for explant of suspected pump thrombus or infection and lead fracture, the presence of pump thrombus was identified in 47 of 51 (92%) and 6 of 19 (32%), respectively. The median of 1) all LDH values, 2) maximum LDH values, and 3) interval change in LDH between 6 and 2 months before device explant were 1,061, 1,940, and -27 IU/L with thrombus present and 533, 504, and 13 IU/L in the absence of thrombus. Density estimation of LDH concentrations identified that a LDH value of 1,155 IU/L in the 6 months preceding pump thrombus had a 78% sensitivity and 90% specificity for findings of pump thrombus at the time of pump analysis.
  
  
  CONCLUSIONS
  Pre-explant LDH concentrations significantly correlated with findings on manufacture-performed pump analysis. These data validate LDH surveillance as an important clinical tool for identification of pump thrombus.
authors.affiliation: Department of Cardiac Surgery, University of Michigan, Ann Arbor, Michigan.
authors.forename: Vikram
authors.initials: V
authors.lastname: Sood
authors.affiliation: Department of Cardiac Surgery, University of Michigan, Ann Arbor, Michigan.
authors.forename: Osman
authors.initials: O
authors.lastname: Alam
authors.affiliation: Division of Cardiac Surgery, University of Rochester, Rochester, New York.
authors.forename: Vakhtang
authors.initials: V
authors.lastname: Tchantchaleishvili
authors.affiliation: Department of Cardiac Surgery, University of Michigan, Ann Arbor, Michigan.
authors.forename: Francis D
authors.initials: FD
authors.lastname: Pagani
authors.affiliation: Department of Cardiac Surgery, University of Michigan, Ann Arbor, Michigan.
authors.forename: Keith D
authors.initials: KD
authors.lastname: Aaronson
authors.affiliation: Department of Cardiac Surgery, University of Michigan, Ann Arbor, Michigan.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Haft
authors.affiliation: Department of Cardiovascular Surgery, Mayo Clinic, Rochester, Minnesota.
authors.forename: David L
authors.initials: DL
authors.lastname: Joyce
authors.affiliation: Department of Cardiovascular Surgery, Mayo Clinic, Rochester, Minnesota.
authors.forename: Lyle D
authors.initials: LD
authors.lastname: Joyce
authors.affiliation: Department of Cardiovascular Surgery, Mayo Clinic, Rochester, Minnesota.
authors.forename: Richard C
authors.initials: RC
authors.lastname: Daly
authors.affiliation: Department of Cardiovascular Surgery, Mayo Clinic, Rochester, Minnesota.
authors.forename: Simon
authors.initials: S
authors.lastname: Maltais
authors.affiliation: Department of Cardiovascular Surgery, Mayo Clinic, Rochester, Minnesota. Electronic address: stulak.john@mayo.edu.
authors.forename: John M
authors.initials: JM
authors.lastname: Stulak
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D020878:Device Removal; D019544:Equipment Failure Analysis; D005260:Female; D006333:Heart Failure / Q000201:enzymology* / Q000628:therapy*; D006353:Heart-Assist Devices; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D013927:Thrombosis / Q000175:diagnosis / Q000201:enzymology* / Q000209:etiology; D055815:Young Adult
chemical_list: D007770:L-Lactate Dehydrogenase