NGF and heart disorder: Future research in human tissue or human subjects focusing for example on specific innervation of the RV outflow tract, distribution of cardiac afferents, regional differences in nerve growth factor or nitric oxide synthase expression, and differing effects of left- or right sided innervation on both the LV and the RV, would be highly valuable to comprehend the influence of cardiac innervation of disease course and potentially adjust treatments for specific cardiac diseases related to cardiac autonomic (dys)function.