Electronic Health Record (EHR) systems offer significant benefits for healthcare. The improved availability of healthcare information from multiple locations contributes to the accuracy and timeliness of care, and should lead to overall improved quality of healthcare delivery. Practical experience and relevant research demonstrate that there are many technological issues that need to be addressed for modern healthcare systems to be effective in sharing EHRs as the structure and size of the healthcare data have changed considerably over time. Recent literature shows that the emerging NoSQL databases have significant advantages such as easy and automatic scaling, better performance and high availability which address the limitations of relational databases in distributed healthcare systems. In this paper we reviewed EHRs and the key features of NoSQL databases. We then evaluated the suitability of NoSQL databases in meeting the requirements of national EHR systems in sharing EHRs in a distributed system environment.