Which factors predict the recovery of natural heart function after insertion of a left ventricular assist system?
BACKGROUND
Recent reports have demonstrated that use of a left ventricular assist system (LVAS) can initiate recovery of cardiac function, and subsequent weaning from the LVAS has attracted considerable interest. In this study we investigated reliable predictors of LVAS weaning.


METHODS
Eighty-two patients underwent LVAS implantation between April 1994 and July 2006 at our institution. Cardiac function was restored in 8 patients, who were weaned from LVAS after a mean of 5 months (Group R). Thirty-three patients remained on LVAS support for >1 year (Group N) because natural heart function did not show adequate improvement. We retrospectively evaluated the differences between these two groups. Group R was younger, and had a shorter duration of heart failure than Group N (23.4 vs 36.7 years and 13.3 vs 56.1 months, p < 0.01, respectively). Pathologic findings showed that the interstitial fibrosis score was lower in Group R (p < 0.01). Three months after LVAS insertion, B-type natriuretic peptide (BNP) and fractional shortening (FS) were more favorable (66.6 +/- 46 vs 264.5 +/- 170 pg/ml, p < 0.01, and 23 +/- 17.1 vs 12 +/- 9.1%, p < 0.05, respectively) in Group R. Furthermore, Group R received a higher dose of beta-blocker (15.4 +/- 8.4 vs 5.8 +/- 3.9 mg, p < 0.05).


CONCLUSIONS
Younger age, shorter history of heart failure, and less interstitial fibrosis were effective predictors of weaning from LVAS. Restoration of natural heart function was more rapid and more persistent in candidates for LVAS explantation, and presence of beta-blocker played a prominent role in improving cardiac function after LVAS implantation.
Mano
A
A
Department of Organ Transplantation, National Cardiovascular Center, Osaka, Japan. mano@hsp.ncvc.go.jp
Nakatani
T
T
Oda
N
N
Kato
T
T
Niwaya
K
K
Tagusari
O
O
Nakajima
H
H
Funatsu
T
T
Hashimoto
S
S
Komamura
K
K
Hanatani
A
A
Ueda
I H
IH
Kitakaze
M
M
Kobayashi
J
J
Yagihara
T
T
Kitamura
S
S
D000293:Adolescent; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000328:Adult; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology; D002227:Carbazoles / Q000494:pharmacology; D000077261:Carvedilol; D005260:Female; D006321:Heart / Q000187:drug effects / Q000502:physiology*; D006353:Heart-Assist Devices; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood; D011237:Predictive Value of Tests; D011412:Propanolamines / Q000494:pharmacology; D020127:Recovery of Function / Q000187:drug effects / Q000502:physiology*; D012189:Retrospective Studies; D013997:Time Factors; D018487:Ventricular Dysfunction, Left / Q000188:drug therapy / Q000503:physiopathology* / Q000601:surgery
D000319:Adrenergic beta-Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D002227:Carbazoles; D011412:Propanolamines; D000077261:Carvedilol; D020097:Natriuretic Peptide, Brain