This paper presents a conceptual model for integrating Artificial Intelligence (AI), Blockchain, and Big Data to enhance healthcare data security, privacy, and patient outcomes. The rapid digitization of healthcare has led to an increase in the volume and complexity of healthcare data, which in turn has raised significant challenges regarding data protection and patient privacy. The paper explores the potential of AI, blockchain, and big data to mitigate these challenges and improve the quality of care. AI is examined for its role in securing sensitive data through encryption, improving decision-making processes, and detecting security threats. Blockchain is explored for its ability to ensure data integrity, decentralize storage, and facilitate secure data sharing through smart contracts. Furthermore, big data analytics is discussed for its capacity to predict patient outcomes, integrate diverse healthcare data sources for holistic insights, and ensure privacy compliance. Despite the promise of these technologies, the paper also addresses the technical, regulatory, and operational challenges associated with their adoption, and proposes risk mitigation strategies. Finally, the future outlook highlights emerging AI, blockchain, and big data innovations that could further strengthen healthcare data security and improve patient care.