Cardiac patching and the regeneration of infarcted myocardium: where do we go from here?

Serpooshan V, Zhao M, Metzler SA et al. The effect of bioengineered acellular collagen patch on cardiac remodeling and ventricular function postmyocardial infarction. Biomaterials 34, 9048-9055 (2013). The decline of cardiac function in the post-myocardial infarcted (MI) heart is due to two essential problems: massive loss of contractile cardiomyocytes, and loss of structural and mechanical tissue integrity due to ongoing remodeling of scar tissue, often leading to left ventricular dilation. Serpooshan et al. demonstrate that an engineered acellular type I collagen patch with optimized mechanical properties, grafted onto the epicardium of infarcted adult murine hearts following ligation of the left anterior descending artery, significantly improves cardiac function and reduces left ventricular remodeling 4 weeks postinjury. While these short-term results are encouraging and, like in other studies, prove the relevance of mechanically supporting the injured myocardium, optimization of the approach in terms of time and manner of intervention, as well as origin of the biomaterial, is needed to warrant future clinical application.