Design a Heart Valve Model

The Project

For this project we have to design a functioning heart valve model. Our Challenge Problem for this project was: "You are a team of engineers for a bio-materials company that has a cardiovascular systems client who wants you to develop a model that can be used to test the properties of heart valves without using real specimens." In order to begin this project we had to start by researching all the different components to a heart.

Research

Identify major structures of the human heart on diagrams and virtual specimens:

Major structures of the human heart include four different types of chambers. These four chambers are the left atrium and right atrium and two lower chambers called the left and right ventricles. The heart is also made up of four valves which are the tricuspid, pulmonary, mitral and aortic valves. The heart functions as a pump, and its valves act as controls to help ensure the correct direction and pacing of blood flow. The heart’s function is for pumping blood, supplying oxygen and nutrients, and removing metabolic waste such as carbon dioxide from all the tissues in the body. The heart and a network of arteries and veins comprise the cardiovascular system.

Describe the flow of blood through the human heart:

Blood is pumped into the pulmonary arteries in the lungs from the right ventricle after entering the right atrium from the body. After absorbing oxygen, the blood returns to the heart through the pulmonary veins, passing through the left atrium, left ventricle, and aorta before leaving the body through the tissues.

Describe the structure and function of heart valves:

The valves prevent the backward flow of blood. These valves are actual flaps that are located on each end of the two ventricles. They act as one-way inlets of blood on one side of a ventricle and one-way outlets of blood on the other side of a ventricle.

Valve tissue anatomy:

Valves are highly organized connective tissue structures populated with dynamic cell populations. Valvulogenesis occurs after the initial stages of cardiogenesis as a result of endocardial cushion formation and extensive remodeling of the extracellular matrix

Content

Anatomy and Structures of the Heart:

• Aorta ascendens- the beginning portion of the largest blood vessel in your body. It carries oxygen-rich blood from your heart to the rest of your aorta.

• Ligamentum arteriosum (Ductus arteriosus)- is a fibrous remnant of the fetal ductus arteriosus (ductus Botalli, Botallo's duct)

• Truncus pulmonalis- the solitary arterial output from the right ventricle, transporting deoxygenated blood to the lungs for oxygenation.

• Auricula dextra- a small conical muscular pouch, the margins of which present a dentated edge.

• Auricula sinistra- the small conic projection from the left atrium of the heart.

• Atrium sinistrum- the left upper chamber of the heart that receives blood from the pulmonary veins

• Atrium dextrum - the right upper chamber of the heart that receives blood from the venae cavae and coronary sinus

• Vena pulmonalis dextra inferior - the vein returning oxygenated blood from the inferior lobe of the right lung to the left atrium

• Vena pulmonalis dextra superior - either of two pulmonary veins (left and right) returning blood from the superior lobes of the lungs

• Vena pulmonalis sinistra inferior - the vein returning oxygenated blood from the inferior lobe of the left lung to the left atrium

• Vena pulmonalis sinistra superior-Either of two pulmonary veins (left and right) returning blood from the superior lobes of the lungs. Any of four veins that carry arterial blood from the lungs to the left atrium of the heart.

• Venae pulmonales - Veins that transfer oxygenated blood from the lungs to the heart

• Vena cava inferior- carries blood from the legs, feet, and organs in the abdomen and pelvis. The vena cava is the largest vein in the body.

• Vena cava superior-The superior vena cava carries blood from the head, neck, arms, and chest. The vena cava’s communicate with each other through the collateral vessels.

• Ventriculus dexter- The chamber on the right side of the heart that receives venous blood from the right atrium and pumps it into the pulmonary trunk.

• Ventriculus sinister-The lower chamber on the left side of the heart that receives the arterial blood from the left atrium and drives it by the contraction of its walls into the aorta.

• Arteria coronaria dextra - The right coronary artery (RCA) is one of two main coronary vessels that supply the myocardium.

• Arteria coronaria sinistra - The left coronary artery (LCA) is one of two coronary vessels (heart vessels) that supply blood to the heart muscle.

• Sinus coronarius - The coronary sinus is a large venous structure located on the posterior aspect of the left atrium, coursing within the left atrioventricular groove.

• Vena cardiaca magna - The great cardiac vein is a large blood vessel found on the anterior (sternocostal) surface of the heart.

• Vena cardiaca media - a vein that collects blood from the diaphragmatic surface of the ventricles, follows the posterior longitudinal sulcus, and empties into the coronary sinus.

• Vena cardiaca parva - A surface vein of the heart that begins at the apex, runs along the right ventricle, and follows the coronary sulcus to the right to drain into the coronary sinus.

• Vena/e ventriculi sinistri posteriores - the vein that drains blood from the posterior surface of the left ventricle into the coronary sinus.

• Cor - Cor pulmonale is a condition that causes the right side of the heart to fail. Long-term high blood pressure in the arteries of the lung and right ventricle of the heart can lead to cor pulmonale.

What each valve of the heart does:

• Tricuspid Valve- controls the flow of blood from your heart's right atrium (top chamber) to the right ventricle (bottom chamber)

• Pulmonary Valve- acts like a one-way door from your heart's right ventricle to the lungs. Blood flows from the right ventricle through the pulmonary valve to the pulmonary artery and then into the lungs, where it picks up oxygen to deliver to your body

• Mitral Valve- a small flap in the heart that stops blood flowing the wrong way. Problems with it can affect how blood flows around the body.

• Aortic Valves- controls the flow of blood out from the heart to the rest of the body.

Next Steps:

When we found our materials for the project we then had to test them and find the Young's Modulus of each material we used.

Elasticity and Young’s Modulus:

-Elasticity describes a material property in which the material returns to its original shape after stress has been applied and then removed

- A measurement of the elasticity of a material is called the Young’s modulus, and is determined as a ratio of stress to strain

Ie: Young’s Modulus (Y) =stress/strain

F = 𝒀( ∆𝑳 / 𝑳𝟎 ) A