Creating the bioartificial myocardium for cardiac repair: challenges and clinical targets Expert Rev. Cardiovasc. Ther. 11(12), 1701–1711 (2013) Juan C Chachques* 1 , Manuel Monleon Pradas 2 , Antoni Bayes-Genis 3 , Carlos Semino 4 1 Cardiovascular Surgery Department and Laboratory of Biosurgical Research, Pompidou Hospital, University of Paris Descartes, 56 rue Leblanc, 75015 Paris, France 2 Center of Biomaterials and Tissue Engineering, Polytechnic University of Valencia, Valencia, Spain 3 Cardiology Department, IGTP, Hospital Germans TriasPujol, Badalona, Barcelona, Spain 4 Department of Bioengineering, IQS-University Ramon Llull, Barcelona, Spain *Author for correspondence: Tel.: +33 613 144 398 Fax: +33 156 095 903 j.chachques@egp.aphp.fr The association of stem cells with tissue-engineered scaffolds constitutes an attractive approach for the repair of myocardial tissue with positive effects to avoid ventricular chamber dilatation, which changes from a natural elliptical to spherical shape in heart failure patients. Biohybrid scaffolds using nanomaterials combined with stem cells emerge as new therapeutic tool for the creation of ‘bioartificial myocardium’ and ‘cardiac wrap bioprostheses’ for myocardial regeneration and ventricular support. Biohybrids are created introducing stem cells and self-assembling peptide nanofibers inside a porous elastomeric membrane, forming cell niches. Our studies lead to the creation of semi-degradable ‘ventricular support bioprostheses’ for adaptative LV and/or RV wrapping, designed with the concept of ‘helical myocardial bands’. The goal is to restore LV elliptical shape, and contribute to systolic contraction and diastolic filling (suction mechanism). Cardiac wrapping with ventricular bioprostheses may reduce the risk of heart failure progression and the indication for heart transplantation. KEYWORDS: bioartificial myocardium • biohybrid scaffolds • bionanomaterials • cardiac bioregeneration • cardiomyoplasty • cell transplantation • heart failure • myocardial infarction • myocardial regeneration • tissue engineering Myocardial ischemia is leading cause of heart failure (HF) in all over the world. Following myocardial infarction the irreparable loss or dysfunction of cardiomyocytes occurs due to sudden deprivation of oxygen supply to the heart. Heart has very limited regeneration capacity as most of the myocytes seems to be terminally differentiated, only small fraction of myocytes retain the capacity to replicate. Until now, drug therapy, surgical procedures (e.g., CABGs, ventricular remodeling and restora- tion, dynamic cardiomyoplasty), heart trans- plantation and mechanical circulatory assist devices are used as treatment when hearts are irreparably damaged. It is evident that it is necessary to develop more effective, less inva- sive, therapeutic strategies for HF. Stem cells- based therapies give new hope in the field of regenerative medicine, as stem cells have ability to differentiate into same as well as different tissue types and to regenerate themselves without losing their differentiation potential. This property of differentiation is being explored for the regeneration of several dam- aged tissues [1,2]. Post-ischemic ventricular dilatation & remodeling Cardiac remodeling refers to the changes in size, shape, structure and physiology of the heart after injury to the myocardium. Dilated cardiomyopathy from many causes results in a change in ventricular geometry, whereby the elliptical chamber becomes more spherical. This change in architecture alters myocardial fiber direction and diminishes function. The early changes of increased spherical configura- tion lead to impairment of ventricular function and may lead to mitral valve regurgitation. The extracellular matrix (ECM) is mainly composed of collagen which gives structural strength to the left ventricle (LV). After myo- cardial infarction, not only the changes affect the contractile element of the myocardium (cardiomyocytes) but also the ECM. Cardio- myocyte death and scar formation, which are www.expert-reviews.com 10.1586/14779072.2013.854165 Ó 2013 Informa UK Ltd ISSN 1477-9072 1701 Review