- Bioengineering covers a broad spectrum of research and development fields such as, biomechanics, biomaterials, and bioelectric engineering. Understanding the properties and mechanism of the cardiovascular system is very helpful in disease prevention, treatment and diagnosis. Bioengineering has been used to make models that simulate blood flow using engineering principles with the hopes of providing a better understanding of the way cardiovascular system functions. The models take into consideration the physiology of the cardiovascular system, and the blood's fluid mechanics. Bioengineering also uses engineering principles to design cardiovascular devices and evaluate their performances for different treatment strategies.
- In the following example, bioengineering principles are applied to the cardiovascular system through the use of electrical elements and an electric circuit. The researchers took different electrical elements and matched them to different mechanical properties of the heart, the blood vessels and the blood.
0.01ml/Pa = 1 µF
Compliance ≡ capacitance
1 Pa.s 2 /ml = 1 µH
Blood inertia ≡ inductor
1 Pa.s/ml = 1 kΩ
Flow resistance ≡ resistance
1mmHg = 1 volt
Blood pressure ≡ voltage
133416 ml = 1A
Blood volume ≡ charge
The relationships between the cardiovascular system's elements are written into the following formulas:
R = 8lµ(pi)/A^2
R = Blood vessel resistance,
µ = the blood viscosity,
l = the length of artery segment
A = cross sectional area of the segment of the artery.
The inertia of the blood (L) which simulated by inductors is calculated by the following formula.
L = 9lρ/ (4A)
ρ = density of the blood.
The capacitor or resistance:
C = 3l(pi)r^3/ (2Eh)
r = radius of artery
E = Elasticity module
h = thickness of the arteries
The capacitor represents the peristaltic motion of the vessel that expands and contracts as it the blood flows through it. This is equivalent to the action of a capacitor in an electric circuit. Once they had done all the calculators the researchers designed a complex circuit board of all the heart and the different arteries. The completed model was able to predict the function of cardiovascular system. - Jarvik-7 Artificial Heart
By combining biomedical sciences and engineering, researchers are able to discover innovative solutions to improve human health. By equating the heart, arteries and the movement of the blood as it flows through the cardiovascular system to mechanical models; in this example of an electrical circuit, it is possible to observe how the blood flow or heart behaves under certain stress conditions. The above model also includes the effect exerted by the capillaries and peristalsis creating a realistic image. An example of bioengineering at its best is the Jarvik-7 artificial heart, a biomedical application of mechanical engineering.
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