Principal Investigator Charles Sodini
Cardiac output (CO) is one of several parameters used by cardiologists to stratify risk of patients with cardio-vascular disease and has significant clinical relevance. CO is currently obtained in the ICU setting through right heart catheterization, an invasive method. This kind of procedure brings with it increased financial cost and risk to the patient. Consequently, non-invasive methods, such as ballistocardiography (BCG), have been gaining more traction and are seen as potential candidates for measuring cardiovascular parameters such as CO.
BCG utilizes detection of the body’s recoil from the ejection of blood into the arterial system. Due to its nature, BCG is prone to noise and ensemble averaging of multiple cardiac cycles is used to obtain a waveform with higher signal-to-noise ratio. An electrocardiogram (ECG) handlebar is used to generate the ECG waveform that sets the timing of the cardiac cycles for this technique. The most notable features of the BCG waveform (I, J, and K waves) are driven by the difference in blood pressure between the inlet and outlet of the ascending aorta during a cardiac cycle. Several parameters derived from these features in the waveform, such as I-J amplitude, IJK width, and the R-J interval, can be used to determine a patient’s stroke volume. Once the stroke volume is known, it can be used alongside the heart rate to calculate the cardiac output. This kind of device can be used for continuous monitoring of a patient in the home setting, removing many of the limitations seen with invasive methods.