Different health data are collected and processed by different medical information systems. Generally, health data is collected by hospitals and stored in the form of Electronic Health Records (EHR). However, as this data contains confidential data, it has become a target for cyber-attacks. Also, as the medical data contains life-critical information, its legitimate origin, reliability and trustworthiness - i.e., data integrity - are particularly important. In the last years, blockchain - a timestamped hierarchical and chronologically- ordered chain of blocks has been proposed as a suitable solution to address the challenges with data integrity. Hyperledger Fabric is an open-source distributed ledger platform allowing enterprise-grade- level solutions to be developed. Therefore, this study aims to present a part of the initial architecture for supporting the integrity of EHRs when exchanging them between organizations. The architecture is based on a blockchain-based system using Hyperledger Fabric technology. Additionally, evaluation methods are proposed to analyze the credibility of architecture in future works.