LATISSIMUS-DORSI CARDIOMYOPLASTY - A CHRONIC EXPERIMENTAL PORCINE MODEL - FEASIBILITY STUDY OF CARDIOMYOPLASTY IN DANISH LANDRACE PIGS AND GOTTINGEN MINIPIGS

Cardiomyoplasty is an experimental treatment for end-stage heart failu re. We hypothesized that the porcine latissimus dorsi muscle (LDM) in an experimental porcine model is a suitable surrogate for a clinically relevant evaluation of this concept, Fourteen Danish Landrace (DL) pi gs and six Gottingen minipigs (GM) were studied. The LDM was evaluated immediately after surgical dissection and in various phases: phase 1 (n = 4)-outcome of a partial vascular isolation (vascular delay), 2 to 3 weeks prior to heart wrapping in DL pigs; phase 2 (n = 6)-long-term flap survival of nonstimulated LDM cardiomyoplasty in DL pigs; phase 3 (n = 6)-outcome of nonstimulated cardiomyoplasty in GM; phase 4-one DL pig had dynamic cardiomyoplasty performed and was subjected to low- intensity LDM stimulation for 8 months. Isolation of the LDM of DL pig s and GM as a pedicled graft had no acute deleterious impact on the gl obal blood supply. In phase 1a, partial vascular isolation and in situ recovery of the LDM resulted in a muscle encapsulated in fibrotic tis sue, which hampered a later heart wrap. In phase 1b, a less extensive dissection diminished fibrosis and allowed subsequent wrapping. In pha se 2, after 6 weeks of nonstimulated LDM cardiomyoplasty, the LDM of D L pigs was viable, with excellent heart-muscle integration. In phase 3 , the same procedure applied in GM yielded the same result as that in DL pigs, but with a higher success rate owing to the learning phase.