How is a fetal pig heart different from a human being?

Students in Upper School Science Teacher Stacey Morgan’s Anatomy and Physiology class have been studying the human heart. They learned about the valves, aorta, ventricles, and veins. They have studied how the heart functions as it pumps blood throughout the body, sending oxygen and nutrients and carrying away unwanted carbon dioxide and waste products.

There’s only so much you can learn from a book, though, and even plastic models, while realistic, aren’t as good as the original. It’s not possible to bring human hearts into the lab to study, so Morgan found the next best thing: pig hearts. “I think it’s important for the students to see and feel tissues, as that can help them better understand why and how they function the way they do,” she said.

Pig hearts are a great way to get an idea of the anatomy of human hearts because they are very similar in size, structure, and function. Like human hearts, pig hearts consist of four chambers (two atriums and two ventricles). They also have four valves and an aorta, just like humans.

During the 30-minute dissection, students are able to identify the different parts of the heart and trace the path of blood flow. They can note any questions that arise, since Morgan has arranged for a cardiothoracic surgeon to virtually visit MICDS as part of her medical speaker series.

Pig hearts are used to study the anatomy of human hearts because they are very similar in structure, size and function to human hearts. These similarities, combined with the fact that they are much more readily available than human hearts, make them an ideal choice for research and study.

Similarities

Like a human heart, a pig heart consists of four chambers: two atriums and two ventricles. Likewise, consistent with the structure of a human heart, it has four valves and an aorta. These similarities allow blood to flow through a pig’s heart in the same way it flows through a human’s heart. In fact, pig hearts are so similar to human hearts that tissue from pig hearts is used to make heart valve replacements for humans. Of course, the tissue is treated before surgery to decrease the likelihood of the recipient’s immune system rejecting it.

References

• Goshen College: Human/Pig Comparisons
• University of Utah, Scientific Computing and Imaging Institute: What Does a Real Heart Look Like

Resources

• The University of Texas at Austin: Xenotransplants:Using Animal Organs to Save Human Lives
• Clemson University: A Valve for Saving Your Heart

Writer Bio

Margie English, a freelance writer based in Alabama, has been writing education-related articles since 2001. Her work appears in various online publications. She has a master's degree in education and taught English for seven years before starting her writing career.

Recently much interest has been centred towards the comparison of a pig’s heart and human heart in the pursuit of Xenotransplantation. This is because there has been a growing demand of organ transplantation which is unmet by the number of human donors (Samstein and Platt, 2001). Although, both belong to the genera of Mammalian origin there are marked difference in the anatomy of their hearts and also their associated physiological functioning. Both the hearts are divided into the auricular and ventricular chambers and have their drainage through the pulmonary arteries and aorta into the lesser and greater circulation. The myocardial volume supplied by left coronary arteries are higher and dominant compared to right coronary arteries in both these hearts as the left heart needs more oxygen supply for its greater activity to pump blood into the systemic circulation (Cooper, Gollackner and Sachs, 2002).

The coronary arteries arise from the aortic bulbus in a similar fashion in both these groups. Further the left coronary artery is very short and divides into an interventricular anterior branch and a left circumflex branch in both these species. These branches mainly give off collateral branches that supply the left atrium and the ventricles (Cooper, Gollackner and Sachs, 2002). The interventricular anterior branch gives off a proximal wide interventricular septal branch that spreads into the dorsal and central parts of the interventricular septum in both these species. The anastomoses between the various branches of coronary arteries are common to both the group of hearts (Cooper, Gollackner and Sachs, 2002). However there are quite a few differences that must be considered from a physiological and immunological standpoint before considering xenotransplantation of a pig’s heart into a human being. The comparison of both hearts is discussed as follows (Cooper, Gollackner and Sachs, 2002):

Pigs like other mammals have a four-chambered heart. The right side of the heart pumps blood to the lungs (pulmonary circulation), and the left side pumps blood out to the rest of the body (systemic circulation). Each side of the heart has two chambers, the upper chambers are called atria and the lower chambers are called the ventricles. Deoxygenated blood enters the heart at the right atrium via the superior vena cava (vein), then travels into the right ventricle which pumps the blood out to the lungs via the pulmonary trunk (artery). After oxygenation, the blood travels back to heart via the pulmonary veins and enters the left atrium. Lastly, the blood enters the left ventricle which pumps the blood out to the body via the aorta, which is the largest artery in the body.

How is a fetal pig heart similar to a human heart?

How is pig anatomy different from human anatomy?