Modeling the heart’s reaction to narrow blood vessels

Cardiovascular diseases are the largest cause of death globally, making it a critical area of focus. The circulatory system is required to make the heart function. One component of this system is blood vessels, which is the focus of our study. Whether due to low temperatures or a medical condition, blood vessels can constrict, occasionally to a dangerous degree. Despite the serious consequences narrow blood vessels can have on one’s body, due to their complexity and size, there is little information pertaining to how their constriction relates to the heart’s ability to pump blood. Therefore, our work aims to demonstrate the numeric relationship between a blood vessel's diameter and the number of pumps needed to transport blood. We explored this concept using a water bottle model to represent the heart, and straws of varying diameters to represent the blood vessels. The experiment recorded the number of pumps necessary to transport 200 mL of red-dyed water to a second bottle using straws. We hypothesized that the number of pumps would increase as the diameter decreased, and that there would be a linear relationship between these variables. The data supported the numeric relationship we hypothesized, in which the largest diameter straw, 1 cm, required the least pumps and the smallest diameter, 0.4 cm, required the most. Our results depict how the heart must overcompensate to transport blood through narrow vessels, providing a better understanding of how the heart behaves when vessels constrict.