In this paper, an overview of a brain-heart monitoring system is first given. The latest development in miniature brain-heart monitoring system for emerging health applications is highlighted. Finally, the development of a low power biomedical signal processing and image reconstruction SoC design is presented. The significance of this SoC is to enable practical developments of portable real-time brain-heart monitoring systems. The proposed architecture comprises a novel functional near-infrared (fNIR) diffuse optical tomography system for brain imaging, an independent component analysis (ICA) processor for electroencephalogram (EEG) signal analysis, and a heart rate variability (HRV) analysis processor for electrocardiogram (ECG) signal analysis. Biomedical signals acquired from front-end sensor modules are processed in real-time or bypassed according to user settings. The processed data or biomedical signals is then losslessly compressed and sent to a remote science station for further analysis and 3D visualization. The final SoC is fabricated in UMC 90nm CMOS technology