This paper presents a first-time review of the open literature focused on the significance of big data generated within nano-sensors and nano-communication networks intended for the future healthcare and biomedical applications. It is aimed toward the development of modern smart healthcare systems enabled with P4, i.e., predictive, preventive, personalized and participatory capabilities to perform diagnostics, monitoring and treatment. The analytical capabilities that can be produced from the substantial amount of data gathered in such networks will aid in exploiting the practical intelligence and learning capabilities that could be further integrated with conventional medical and health data leading to more efficient decision making. We have also proposed a big data analytics framework for gathering intelligence, form the healthcare big data, required by futuristic smart healthcare to address relevant problems and exploit possible opportunities in the future applications. Finally, the open challenges, the future directions for researchers in the evolving healthcare domain, are presented.