Cardiac improvement during mechanical circulatory support: a prospective multicenter study of the LVAD Working Group.
BACKGROUND
Myocardial recovery after left ventricular assist device (LVAD) support has been reported. The LVAD Working Group Recovery Study was a prospective multicenter trial to assess the incidence of myocardial recovery in patients bridged to cardiac transplantation.


RESULTS
After LVAD implantation, patients were evaluated with the use of rest echocardiograms with partial LVAD support and cardiopulmonary exercise testing. Dobutamine echocardiography with hemodynamic measurements was performed in those patients with left ventricular ejection fraction >40% during resting studies. Histological analysis was performed on myocardial samples taken at LVAD implantation and explantation. Sixty-seven LVAD patients with heart failure participated in the study. After 30 days, significant improvement occurred in left ventricular ejection fraction (17+/-7% versus 34+/-12%; P<0.001) and reductions in left ventricular end-diastolic diameter (7.1+/-1.2 versus 5.1+/-1.1 cm; P<0.001) and left ventricular mass (320+/-113 versus 194+/-79 g; P<0.001) compared with before LVAD. Thirty-four percent of patients had left ventricular ejection fraction >40% with partial device support. Left ventricular ejection fraction decreased over time to pre-LVAD measurement by 120 days. Peak VO2 improved with mechanical support (13.7+/-4.2 versus 18.9+/-5.5 mL/kg per minute, 30 versus 120 days; P<0.001). Tissue analysis revealed significant reductions in myocyte size, collagen content, and cardiac tumor necrosis factor-alpha. Six subjects (9%) underwent LVAD explantation for recovery.


CONCLUSIONS
Cardiac function improves significantly after device implantation. Although cellular recovery and improvement in ventricular function are observed, the degree of clinical recovery is insufficient for device explantation in most patients with chronic heart failure.
Maybaum
Simon
S
Albert Einstein College of Medicine, Center for Advanced Cardiac Therapy, 3400 Bainbridge Ave, 7th Floor, Bronx, NY 10467-2490, USA. smaybaum@montefiore.org
Mancini
Donna
D
Xydas
Steve
S
Starling
Randall C
RC
Aaronson
Keith
K
Pagani
Francis D
FD
Miller
Leslie W
LW
Margulies
Kenneth
K
McRee
Susan
S
Frazier
O H
OH
Torre-Amione
Guillermo
G
D002317:Cardiovascular Agents / Q000627:therapeutic use; D003131:Combined Modality Therapy; D016207:Cytokines / Q000096:biosynthesis; D004280:Dobutamine / Q000627:therapeutic use; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D005355:Fibrosis; D006333:Heart Failure / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology / Q000601:surgery / Q000628:therapy*; D006334:Heart Function Tests; D016027:Heart Transplantation; D006353:Heart-Assist Devices / Q000706:statistics & numerical data; D006801:Humans; D006984:Hypertrophy; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology; D032383:Myocytes, Cardiac / Q000378:metabolism / Q000473:pathology; D011446:Prospective Studies; D016037:Single-Blind Method; D013318:Stroke Volume; D016896:Treatment Outcome; D014463:Ultrasonography
D002317:Cardiovascular Agents; D016207:Cytokines; D004280:Dobutamine