The functionality of smart healthcare systems has been greatly improved by the quickly developing Internet of Medical Things (IoMT), with its cutting-edge real-time services. However, there are significant privacy and security problems with IoMT, which are exacerbated by the wide range of these devices, making it more challenging to provide a unified security solution. Moreover, the prevalent cloud-centric IoMT healthcare systems, which rely on cloud computing for Electronic Health Records (EHR) and medical services, make a decentralized IoMT healthcare model impractical. This study proposes an innovative blockchain-based architecture that ensures decentralized EHR and smart contract-driven service automation while preserving system security and privacy. Cloud-centric IoMT healthcare systems suffer from excessive latency, storage costs, and single point of failure. These issues are resolved by combining a blockchain-based distributed data storage system with the recently suggested hybrid computing paradigm.