Written by Elisha Kristin Pasco

Pathophysiology and pathology are essentially the same, except the fields have different scopes. Pathology deals with the disease and how it affects your body. Pathophysiology covers more ground. It studies the cause of illness, how it affects your body, the signs and symptoms, and treatment.

Pathophysiology and pathology are the same, but not quite.

Let us first consider etymology, the study of their origin. Both come from the words pathos and logos.

The word pathos is Greek for suffering. The root logos means discourse, defined as a system of formal studying. Together pathos and logos form the word pathology, the study of discomfort. It is the field in medicine that studies the anomalies in your body caused by disease.

Pathophysiology does not only have pathos and logos in its structure. It also has the Greek word physio, nature. When you add the physio together with logos, you get physiology. It studies how your body usually functions.

Adding pathos to physiology creates a different word, albeit related. It is the study of how a disease works and the changes it makes in your body. It also covers the signs and symptoms that you get and help your doctors provide the best possible care.

What is an example of pathophysiology?

Consider the pathophysiology of aortic regurgitation below. It will show you how the field tackles a disease. Before discussing the disorder, consider the different parts and functions of the organs affected.

Anatomy of the Heart

Your heart is a pumping muscle about the size of your fist. It is behind your breastbone, between your lungs. Its apex points at your left hip, with the wide part directed at your shoulder.

Your heart has four chambers. The left and right atrium receive the blood. The left and right ventricles are in charge of discharging the blood. These four chambers are divided by the septum longitudinally.

 The wall between the left and right chambers is the septum. 

Blood flows in your heart through valves. These are doors that ensure your blood is flowing in only one direction. Your heart has two sets of valves. The atrioventricular valves (AV) are between your atria and ventricles. Another set of valves, the semilunar valves, guard the bases between the largest arteries and the ventricles.

Physiology of the Heart

Whenever the heart beats and contracts, it pumps your blood throughout the body. Your ventricles do most of the pumping. With the atria, it alternates between contracting and relaxing.

The tightening of your heart occurs when it contracts, this is the systole. Diastole happens when your heart is at rest, it is relaxing in this stage.

Ventricular filling occurs when the heart is relaxing. The low pressure makes the blood pour from the atria to the ventricles. During this stage, AV valves are open, and the semilunar valves close. 

The semilunar valves open with the rise in blood pressure during systole. The blood strains into the cusps and pushes the semilunar valves open. It is called the ejection phase.

The ejection phase is a period in your cycle where the heart contracts. The AV valves close, allowing the atria to fill with blood.

Clinical Manifestation

Aortic regurgitation (AR) may present itself as either chronic or acute. 

Chronic regurgitation gives your heart time to adjust to the disorder. Usually, the patients do not have symptoms because their hearts can compensate. 

Symptoms appear only when the heart can no longer deal with the volume overload. It usually presents itself through left-sided failure. It occurs when the left ventricle weakens. It can no longer push enough blood around the body.

Acute AR does not give the heart time to adapt. The observable signs are shortness of breath, fluid in the lungs, and low blood pressure. Cardiovascular collapse may also occur. Your heart goes into shock due to the low pressure, which may lead to an abrupt loss in cardiac function.

Physical examinations of patients with chronic aortic regurgitation present the following signs:

• Hyperdynamic and misplaced pulses or the abnormal rise in circulatory volume

• Three heart murmurs may be present

• A high-pitched early diastolic murmur
• A diastolic rumble called the Austin Flint murmur
• A systolic murmur

• A third heartbeat may be present due to the extra volume of blood in the ventricle.

• The arterial impulse found in the left corner of your chest shifts

Observable signs for chronic aortic regurgitation may not be present during physical examination. The expansion of the left ventricle does not misplace the pulse. The diastolic murmur is softer, and the Austin Flint murmur is short.

Etiology

Acute AR may be due to the following disorders: 

Infective endocarditis is a disorder that affects the walls of your heart. It is due to bacteria entering the bloodstream that may lead to the destruction of the aortic valve.

Chest trauma may cause a tear in the aorta connected to your ventricles. It may disturb the aortic valve causing the blood to backflow.

The cause of chronic aortic regurgitation are as follows:

The bicuspid aortic valve is one of the most common causes of aortic regurgitation. Instead of having three cusps, the aortic valves have only two flaps. It hinders their task of preventing the backflow of blood. 

Weight loss medications can change the structure of your valves. It results in your blood leaking back to your ventricles. Examples of these medications are fenfluramine and dexfenfluramine.

Rheumatic fever is also a factor when people develop aortic valve regurgitation. The disorder caused the fibers in your valves to thicken, causing them to curl. When they bend, the boundary is not secured enough to ensure a unidirectional flow. 

Pathophysiology

AR occurs when blood from the aorta leaks back into the ventricle. It occurs due to anomalies in the structure of the aortic valve. 

These changes in the flaps cannot keep the blood flowing in one direction. The left ventricle receives blood from both the right atrium and the aorta. There is a volume overload in the chamber.

The pressure in the left ventricle rises because of the blood from the atria and aorta. Usually, when the heart is at rest, the strain in the chamber is low, blood flows freely from the atria. The walls of your pump will have to compensate for these changes.

If the leakage is gradual, your heart can adapt to the changes. It undergoes a few modifications to maintain your cardiac output. It is the amount of blood your heart pumps per minute.

Due to the volume overload in the left ventricle, the myocardial fibers in your blood stretch. These fibers elongate to compensate for the blood flowing back from the aorta.

When the myocardial fibers of your heart stretch, your left ventricle dilates. It enables the chamber to cater to the extra volume of blood it is receiving. The increase in the blood volume means that your main pump must work harder.

Aside from elongating, your heart compensates through hypertrophy. The walls in your heart harden to maintain the cardiac cycle. It thickens to adapt to the rise in pressure needed to pump the blood out.

Unfortunately, the contractility of the myocardial fibers diminishes over time. The ejection rate of blood outside your heart drops. The diastolic pressure increases with the volume. Your ventricles fail due to overwork; heart failure develops right after.

Treatment

Patients with mild aortic regurgitation usually do not display any symptoms. Usually, the treatment is dependent on whether there are visible signs of the disorder or not. 

If you do not have any symptoms, your doctor will usually opt for regular check-ups. You will have to do this to track the progression of the disease. There might also be a need for regular echocardiograms.

If you are at risk of high blood pressure, medications to lower them are necessary.

If the AR is severe, surgery may be an option. It may be through is open-heart surgery or a minimally invasive one. 

What does pathophysiology mean in simple terms?

Pathophysiology describes the changes in the functions of your body because of disease. These abnormalities may be present in your cells, tissues, organs, and body fluids.

It deals with the discrepancies in your body’s usual functions. It is a field that describes how your body responds to disruptions in its internal and external environment.

What do you write in pathophysiology?

Pathophysiology discusses four elements: etiology, pathogenesis, clinical manifestations, and treatment.

Etiology

Etiology investigates the cause of your disease. It determines whether your disorder is an infection, or if it is hereditary, or an accident. This field describes the disorder that started making alterations in your body.

The following are terms used to describe where your disease may have come from:

• Idiopathic is the term for diseases with unidentifiable causes

• Iatrogenic is the name for diseases that occur due to unnecessary medical treatment.

• Nosocomial are diseases that you get in a hospital due to necessary treatment. 

The Etiologic Classification of Disease are as follows:

o Degenerative diseases

o Iatrogenic diseases

o Idiopathic diseases

o Immunologic diseases

o Infectious diseases

o Inherited diseases

o Metabolic diseases

o Neoplastic diseases

o Nutritional deficiency diseases

o Physical agent-induced diseases

o Psychogenic diseases

Pathogenesis

Pathogenesis discusses the physical manifestations of the disease. It takes note of the changes in your body when you develop the disorder. 

It determines the cause and the set of events that follow. Pathogenesis does this by monitoring your cells, tissues, organs, and systemic functions. 

Clinical Manifestations

Clinical manifestations are the observable signs of disease in your body. These often result coming from pathogenesis. The data is from a series of examinations of the physical and chemical environment of your body.

Treatment

Pathophysiology is necessary when giving treatment. It enables your doctors and nurses to provide the best possible patient care available. They can do this through the proper study of your sickness origins and effects. 

Pathophysiology helps your healthcare providers track the progress of your disease. It also helps them see the effects of your medication because treatment is not just theory. Your body is unique. Thus, treatments that work on others may not be as efficient as yours.

What is clinical pathophysiology?

Clinical pathophysiology identifies the factors that contribute to the disease. It is the field that studies the processes of how you got the disease, why you have it, and its progression in your body. 

It explains the alterations in your physical and chemical environment. This field helps your doctors plan your treatment and give you the best patient care.

Does pathophysiology mean cause?

Pathophysiology does explain the cause of disease, but it is too broad. 

The field of pathophysiology deals with the following questions: How you got the disease? How did it develop in your body? How it affected your organs? Your chemical environment, etc. It does not just look at the cause.

Etiology, the study of the cause of disease, is a subset of pathophysiology. 

In other words, pathophysiology does give you the cause, but it also discusses the mechanisms of the disorder.

Which is the best book for pathophysiology?

The best pathophysiology book depends on how you wish to approach the subject. Textbooks made to cater to medical students are different. They do not cover the basics like anatomy and physiology.

That is why you must know the intended audience of the book.

Clinical Pathophysiology Made Ridiculously Simple by Aaron Berkowitz, M.D., Ph.D.

It is a book for beginners or fields other than medicine. It explains the basics of pathophysiology it does not go any deeper.

Pathophysiology of Disease: An Introduction to Clinical Medicine published by Lange 

If you are a student of medicine, you already know your anatomy and physiology. There is no need for repetitive and redundant information. 

Lange does not only provide you a deeper understanding of the disease but also case studies. These studies, written by doctors and professors, give you different outlooks towards the disease.

References

Albert, C. M., & Stevenson, W. G. (2018). Cardiovascular Collapse, Cardiac Arrest, and Sudden Cardiac Death. In D. L. Kasper, Harrison’s Principles of Internal Medicine. New York: McGraw-Hill.

Brashers, V. L., & Rote, N. S. (2017). Understanding Pathophysiology (Sixth ed.). St. Louis, Missouri: Elsevier Inc.

Hammer, G. D., & McPhee, S. J. (2014). Pathophysiology of Disease: An Introduction to Clinical Medicine. McGraw-Hill Education.

Huether, S. E., McCance, K. L., Brashers, V. L., & S., R. N. (2017). Introduction to Pathophysiology. In S. E. Huether, K. L. McCance, V. L. Brashers, & R. N. S., Understanding Pathophysiology (pp. 55-57). St. Louis, Missouri: Elsevier.

Online Etymology Dictionary. (2021, August 18). Retrieved from pathos: https://www.etymonline.com/word/pathos

pathology. (n.d.). Retrieved August 20, 2021, from Online Etymology Dictionary: https://www.etymonline.com/word/pathology

pathology. (n.d.). Retrieved August 20, 2021, from Merriam-Webster: https://www.merriam-webster.com/dictionary/pathology

Types of Heart Failure. (2018, January 25). InformedHealth.org.

Wang, S. S. (2018, November 19). Aortic Regurgitation. Retrieved from the heart.org Medscape: https://emedicine.medscape.com/article/150490-overview#a5

Witthöft, M. (2013). Encyclopedia of Behavioral Medicine. (M. D. Gellman, & J. R. Turner, Eds.) New York, New York: Springer.