Vascular delay of the latissimus dorsi muscle: an essential component of cardiomyoplasty.
BACKGROUND
Cardiomyoplasty (CMP) uses the latissimus dorsi muscle (LDM) to assist the heart in cases of cardiac failure. Distal ischemia and necrosis of the LDM is a recognized complication of CMP that can reduce distal muscle function and the mechanical effectiveness of CMP.


METHODS
Canine (n = 9) LDMs were subjected to a 10-day period of vascular delay followed by a simulated CMP. Two weeks after simulated CMP (corresponding to the healing delay between CMP and the onset of LDM stimulation used in the clinical setting), LDM perfusion was measured in the distal, middle, and proximal segments of the muscle, and circumferential (distal and middle squeezing muscle function) and longitudinal (proximal pulling muscle function) force generation and fatigue rates were measured. The results were compared with the contralateral nondelayed simulated CMP.


RESULTS
Muscle perfusion was significantly (p < 0.05) greater in the distal and middle segments of vascular-delayed LDMs. Circumferential muscle force generation and fatigue rates were significantly (p < 0.05) improved in the vascular-delayed LDMs.


CONCLUSIONS
Vascular delay can significantly improve LDM perfusion and function in a model that closely reflects clinical CMP, and the use of vascular delay may improve clinical outcomes in CMP.
Carroll
S M
SM
Department of Surgery, School of Medicine, University of Louisville, Kentucky 40292, USA.
Carroll
C M
CM
Stremel
R W
RW
Heilman
S J
SJ
Tobin
G R
GR
Barker
J H
JH
D000818:Animals; D018421:Cardiomyoplasty / Q000379:methods*; D004285:Dogs; D004558:Electric Stimulation; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000098:blood supply*; D012086:Reoperation; D013997:Time Factors