Osmometric Heart Monitoring Device and Methods

An implantable osmotic heart monitoring system comprising:

• an osmotic pH sensor, the osmotic pH sensor configured to generate a signal corresponding to pH of a bodily fluid, the osmotic pH sensor comprising
• a wall member defining an enclosed volume, the wall member comprising a semi-permeable membrane;
• and
• a solution comprising a solvent and a solute, the solution disposed within the enclosed volume, the solute configured to change osmotic strength in a pH range of between about 7.3 and about 7.5;
• the semi-permeable membrane permeable to the solvent and impermeable to the solute;
• and
• a controller in communication with the osmotic pH sensor.