title: Magnitude and time course of changes induced by continuous-flow left ventricular assist device unloading in chronic heart failure: insights into cardiac recovery.
abstract: OBJECTIVE
  This study sought to prospectively investigate the longitudinal effects of continuous-flow left ventricular assist device (LVAD) unloading on myocardial structure and systolic and diastolic function.
  
  
  BACKGROUND
  The magnitude, timeline, and sustainability of changes induced by continuous-flow LVAD on the structure and function of the failing human heart are unknown.
  
  
  METHODS
  Eighty consecutive patients with clinical characteristics consistent with chronic heart failure requiring implantation of a continuous-flow LVAD were prospectively enrolled. Serial echocardiograms (at 1, 2, 3, 4, 6, 9, and 12 months) and right heart catheterizations were performed after LVAD implant. Cardiac recovery was assessed on the basis of improvement in systolic and diastolic function indices on echocardiography that were sustained during LVAD turn-down studies.
  
  
  RESULTS
  After 6 months of LVAD unloading, 34% of patients had a relative LV ejection fraction increase above 50% and 19% of patients, both ischemic and nonischemic, achieved an LV ejection fraction ≥ 40%. LV systolic function improved as early as 30 days, the greatest degree of improvement was achieved by 6 months of mechanical unloading and persisted over the 1-year follow up. LV diastolic function parameters also improved as early as 30 days after LVAD unloading, and this improvement persisted over time. LV end-diastolic and end-systolic volumes decreased as early as 30 days after LVAD unloading (113 vs. 77 ml/m(2), p < 0.01, and 92 vs. 60 ml/m(2), p < 0.01, respectively). LV mass decreased as early as 30 days after LVAD unloading (114 vs. 95 g/m(2), p < 0.05) and continued to do so over the 1-year follow-up but did not reach values below the normal reference range, suggesting no atrophic remodeling after prolonged LVAD unloading.
  
  
  CONCLUSIONS
  Continuous-flow LVAD unloading induced in a subset of patients, both ischemic and nonischemic, early improvement in myocardial structure and systolic and diastolic function that was largely completed within 6 months, with no evidence of subsequent regression.
authors.affiliation: Utah Transplantation Affiliated Hospitals (UTAH) Cardiac Transplant Program, Divisions of Cardiology and Cardiothoracic Surgery, University of Utah Health Sciences Center, Intermountain Medical Center, Salt Lake City, Utah 84132, USA. stavros.drakos@u2m2.utah.edu
authors.forename: Stavros G
authors.initials: SG
authors.lastname: Drakos
authors.forename: Omar
authors.initials: O
authors.lastname: Wever-Pinzon
authors.forename: Craig H
authors.initials: CH
authors.lastname: Selzman
authors.forename: Edward M
authors.initials: EM
authors.lastname: Gilbert
authors.forename: Rami
authors.initials: R
authors.lastname: Alharethi
authors.forename: Bruce B
authors.initials: BB
authors.lastname: Reid
authors.forename: Abdulfattah
authors.initials: A
authors.lastname: Saidi
authors.forename: Nikolaos A
authors.initials: NA
authors.lastname: Diakos
authors.forename: Sandi
authors.initials: S
authors.lastname: Stoker
authors.forename: Erin S
authors.initials: ES
authors.lastname: Davis
authors.forename: Matthew
authors.initials: M
authors.lastname: Movsesian
authors.forename: Dean Y
authors.initials: DY
authors.lastname: Li
authors.forename: Josef
authors.initials: J
authors.lastname: Stehlik
authors.forename: Abdallah G
authors.initials: AG
authors.lastname: Kfoury
mesh_terms: D000368:Aged; D003971:Diastole; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006353:Heart-Assist Devices; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013318:Stroke Volume; D013599:Systole; D014463:Ultrasonography; D016277:Ventricular Function, Left