Myoblast Implantation in Demand Dynamic Cardiomyoplasty: a Bonus or a Must for the Heart Wrap?

Tissue or Cell Cardiac Bioassistance (Cardiac-Bio-Assists) is a biological approach to remedy to cardiac progressive insufficiency based on autologous tissue or cell transplantation. Some of the work-hypotheses are in pre-clinical evaluation (implants of embryonic myocardiocytes and of myoblasts derived from skeletal muscle satellite cell or Skeletal Muscle Ventricle, SMV), others are under preliminary or advanced clinical testing (Dynamic Aortomyoplasty and Dynamic Cardiomyoplasty, DyA and DyC). Dynamic Cardiomyoplasty is a surgical procedure, which could support myocardial function when cardiac insufficiency would become pharmacologically intractable in the middle period. In this procedure a nonessential muscle, the Latissimus Dorsi (LD) is diverted from its normal role, transferred into the chest, and wrapped around the heart (LD Wrap), conditioned to fatigue and activated during systole to provide cardiac assistance. The clinical results of the international and Italian studies are encouraging, but it is still missing an objective evidence of an advantage of the procedure on the optimised pharmacological treatment. The mechanisms of its action are discussed and it remains the risk of myodystrophic lesions of the LD wrap, which could reduce the work capability of the pericardial muscle prosthesis. The Italian MURST-funded “Italian Trial of Demand Dynamic Cardiomyoplasty” is addressing some of these issues by clinical research on the group of Italian patients of Demand Dynamic Cardiomyoplasty, and by animal experiments to develop and test new biotechnological, surgical, clinical and engineering approaches. In particular we will here discuss if increase of muscle mass of the distal part of the LD is desirable and feasible or if it is needed.