Professors Jon Valvano and John Pearce are testing an enhancement to pacemakers that measures heart volume. For many, heart disease is a cycle: the heart swells, the lungs get wet, and drug therapy in a hospital is the treatment. Early detection of increased heart volume could drastically reduce medical expenses and dramatically improve a patient's quality of life.
The best way to measure heart health is pressure-volume analysis. Heart volume is currently expensive to measure and provides only a snapshot view of changing circumstances. Drs. Pearce and Valvano's prototype—currently being tested on animals—would provide continuous monitoring with only an extra chip added to already implanted pacemakers.
A four-electrode catheter is inserted into the heart to generate an electric field and to continuously measure the conductance signal. The reading is adjusted to remove muscle conductance so that just blood conductance is measured. This measurement system will serve as an early warning for impending heart failure and is superior to the current approach of measuring right heart pressure and lung impedance.