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Heart Surgery
Aesha Amin
Independent Study
Mrs. Graves
June 9, 2016
WHAT I KNEW/ WANTED TO KNOW
The heart is one of the most important organs in the body, about the size of a fist. It is
one of the strongest muscle in our body and it pumps about 2,000 gallons of blood in just one
day. It is amazing how such a small organ can do so much work. Without it, we would not be
alive. I have always been fascinated by the way a heart works. The heart is extremely precious,
and if it is not working properly, something has to be done about it. Heart surgeries are
performed in patients with hearts that are damaged and not working as efficiently as they can.
The knowledge of heart surgeries is extremely important because it can improve, and even save
the lives of patients.
Before the research, I did not know a lot about heart surgeries. I knew some basic
information about the heart’s structure and its purpose that I learned in school. But, I did not
know a lot of about heart surgeries, except that they existed. I have always heard people talk
about different types of heart surgeries, but I never really understood what they were talking
about. I was always interested in learning about heart surgeries, and I wanted to know more
about them. This curiosity led to my research question: What are the different types of heart
surgeries, why are they needed, and how are they performed?
The main topic I researched was different types of heart surgeries, but I also decided to
research other related topics, like the structure of the heart and the circulatory system.
Understanding heart surgeries required a complete understanding of the heart since I had to
know the different parts of the heart the surgery was performed on, therefore, I needed a basic
knowledge of the heart. I knew that the heart was a muscle that pumps blood throughout the
body. Arteries carry oxygenated blood to different places that needs oxygen, and veins carry
the blood back to the heart. From the heart, the blood goes to lungs where carbon dioxide is
replaced with oxygen. Then, the oxygenated blood goes back to the heart and other parts of
body. Most heart problems happen because of plaque buildup, usually because of the patient’s
unhealthy lifestyle. With more research on this topic, surgeons can come up with new
procedures that are less invasive and have higher chances of survival.
THE SEARCH
My search took about one month since I had a lot of free time to do my research. I
decided to research one topic every time. At first, I researched about the heart. I learned more
about the structure of the heart like the arteries, veins, valves, ventricles, and atrium. I found
this very useful later during the research because I understood what the articles were talking
about. This part of the research was not challenging because I already had some background
knowledge. If there were certain parts that I did not understand in the article, I researched
more about those topics first, and then continued reading the article. For example, the first
article I read talked about different types of valves, I did not fully understand that section.
Therefore, I researched different types of valves and where they are located. When I though I
knew enough about the heart, I moved on to surgeries.
Researching surgeries was fun and very interesting. I found a lot of basic information
about surgeries from websites designed for patients who needed surgeries. Some of these were
form National Heart, Lung, and Blood Institute and American Heart Association. Those websites
gave me a general idea about the surgery. It usually talking about why the surgery is needed,
and gave very basic information about how they are performed. This part was easy to
understand and did not use advanced vocabulary since it was meant to be read by an average
person.
After getting the general idea, I went on to other websites that had more advanced
vocabulary. One useful website was WebMD. I read many articles on this website for different
procedures and gained a deeper understanding on that topic. This website had more
information than the website I previously used since it was meant for educational purposes. It
had information of the things that had to be done before and after a procedure, although it did
not talk about the actual procedure. This website was easy to read and understand even
though it had more information. If I came across something that I did not understand, I would
research more about that topic.
The websites I previously used did not talk about the actual procedure. But I wanted to
know about the actual procedure, so I had to research further. I looked at other websites, and I
found John Hopkins Medicine to be very useful. This website had step-by-step procedure on
how to perform many different types of surgery. I found this website to be the most useful
because it answered one of my main research question, which was how to perform the surgery.
The steps to perform the procedure were hard to understand since there were a lot of things
that has to be done during a surgery. Since I did not understand a lot of it, I had to look at
videos on YouTube to visually see the procedure. Some of these videos were animated and
some of them were recorded while they were performed. I found the animated videos more
informative since it showed things that you cannot see by just looking, like the insides of a
heart. But, I liked the recorded videos because it was real. I usually understood the video
because I had already read the procedure and knew what was happening. After I had seen the
video, I went back and read the procedure again. I understood the procedure better after
watching the video.
While I was researching, I decided to interview Tanha Patel. She did her senior
mentorship under a cardiologist, and wrote her case studies on CABG and TAVR. Our research
was on similar topics, so I decided to interview her. I wrote a letter of request and emailed it to
her. She responded the next day and we decided on a day for an interview. The interview was
about thirty minutes long and she talking about the procedures and how they are performed. I
also cleared up some questions I had. The interview was useful, and I was exposed to new
procedures that I did not know about before. The interview paved my way for future blog posts.
I researched two other surgical procedures she wrote her case studies on: stents and balloons,
and TAVR.
The most useful thing I got out of the interview was the case studies. Ms. Patel gave me
the case studies she had written her senior year. I read them, and found that they were very
useful and had a lot of information. I found the case study useful because it was written based
on her experience in a hospital.
THE RESULT
The four main types of surgeries I researched were coronary artery bypass grafting
(CABG), heart transplant, transcatheter aortic valve replacement (TAVR), and angioplasty. CABG
is needed when a patient has a blocked coronary artery. Heart transplant is needed when a
patient has a damaged heart and nothing can be done about it. TAVR is needed when a patient
needs a new valve. And, angioplasty is needed when a patient has a blocked artery.
CORONARY ARTERY BYPASS GRAFTING (CABG)
Arteries supply oxygen-rich blood to the different parts of body and muscles. Like all
other tissues in the body, the heart muscle needs oxygen to function. Coronary arteries supply
the heart muscle with blood so that the heart can function. A waxy substance called plaques
can build up in the artery walls and grow over time. They are a serious problems, and may
require heart surgery1. CABG is a type of surgery done to improve blood flow to the heart
muscle and treat coronary heart disease (CHD). CHD is a disease where plaque builds up inside
the coronary arteries that supplies oxygen-rich blood to the heart muscles. One of the
symptoms of CHD is angina, which is a severe chest pain at the center of the chest or below the
rib cage. The pain can spread to other parts of the body. Other symptoms for CHD include lack
of breath, sweating, or dizziness. The plaque built over time can harden or rupture. The
hardening of plaque can reduce blood flow by narrowing arteries. The decreased blood flow
strains and damage the heart muscle. The rupture of plaque can cause a blood clot to form that
will block the blood flow to the heart muscle and cause a heart attack. During CABG, a healthy
artery or vein from another part of the body is used to bypasses the blocked portion of the
artery to provide a new path for the oxygen-rich blood to flow to the heart muscles2.
Tests can be done to see if someone needs CABG. The patient can get a physical exam to
checks heart, lungs, and pulse. The patient can also get an electrocardiogram (EKG),
echocardiography, or coronary angiography. EKG records the heart's electrical activity and
shows signs of heart damage. Echocardiography uses sound waves to create a moving picture
of the heart. It can show areas of poor blood flow and heart muscles that are not contracting
normally. Coronary angiography uses dyes and x-rays to show the insides of coronary arteries2.
Before the procedure is performed, many things have to be done to prepare the patient
for the surgery. Intravenous (IV) lines need to be started in the arm or hands to administer
fluids like medicine or blood. The patient will be given anesthesia so that they are not awake
during the procedure. A breathing tube will be inserted in the throat that will connect to the
ventilator. This tube will breathe for the patient. The anesthesiologist will monitor the patient's
heart rate, blood pressure, breathing, and blood oxygen levels during the whole procedure. The
skin over surgical site will be cleaned with antiseptic solution to prevent infection. Usually, a
healthy artery from the chest called the mammary artery or a vein from the leg called the
saphenous vein will be used to bypass the blocked coronary artery. A cut will be made to get
the blood vessel used for the graft. The vessel will be removed and the incision will be sewed
shut. An incision will be made down the center of the chest, and the breastbone will be cut in
half and spread apart to expose the heart. This reveals a layer of tissue covering the heart called
the pericardium. Another incision is made in the pericardium for a clear view of the heart.
Tubes will be connected to the heart and the blood from the heart will be removed. The bypass
machine will pump blood throughout the body during the procedure. The heart will be stopped
by injected a cold solution. Once the heart is stopped, a cold solution of potassium enriched
saline is injected into the coronary arteries to reduce the temperature of the heart and prevent
tissue damage. One end of the healthy vein will be sewn to the aorta and the other end will be
sewn to the coronary artery below the blockage. Once the blood vessel is sewn, the blood
circulating through the bypass machine will be allowed back into the heart and the machine will
be removed. The breastbone will be sewn together with small wires and the skin over the
breastbone will be sewn together. The surgeons will put tubes in the chest to drain blood and
other fluids around the heart. After the surgery, patients stay in the ICU for one or two days.
Patients are connected to a breathing tube, a mechanical ventilator, a heart monitor, a urinary
catheter and other equipment during the recovery period. After the procedure, the heart
muscles will receive more blood supply through the artery that is not blocked3.
HEART TRANSPLANT
A heart transplant is a surgery done to remove a damaged or diseased heart and replace
it with a healthy donor heart. This requires someone to donate their heart and is done when
there are no other options to fix a patient's heart. The procedure is performed on someone
who has heart damage after a heart attack or a heart failure. The heart for the transplant has to
be donated from someone who is brain-dead but still on life support. The tissue type of the
donor heart should be close to the tissue type of the patient to decrease the chance of the
patient's body rejecting the heart. When the heart is removed from the donor, it has to be
implanted in less than six hours4.
Heart transplant requires three operations. In the first operation, the heart is removed
from the donor. In the second operation, the patient's damaged heart is removed. In the third
operation, the donor heart is implanted5.
Like any other surgery, things like starting an IV line, sedating the patient, and inserting
a tube has to be done. An incision will be made down the center of the chest and the sternum
will be divided in half and spread apart to expose the heart. Tubes will be inserted in the chest
to pump blood throughout the body through a bypass machine so that the body still functions.
The damaged heart will be removed from the patient. Usually, the ventricles are removed, but
the great vessels, right atrium and left atrium of the patient stays. Donor heart will be sewn into
place and blood vessels like the aorta and pulmonary arteries will be connected. The blood
from bypass machine will be allowed back into the heart. The heart will be shocked to restart
the heartbeat and it will be observed to make sure there are no leaks and it functions properly.
The sternum will be sewn together with wires and the skin over the sternum will be sewn back
together. Tubes will be inserted in the chest to drain blood and fluids around the heart 6.
The patient’s body might detect the donor heart as a foreign object and reject it. To
prevent the rejection of the heart, immunosuppression medications will be given to the patient
for the rest of their life. These medications reduce the strength of the body’s immune system so
that the body does not reject the foreign organ. Immunosuppression medications might
increase the chance of an infection because if weakens the immune system. Signs of rejection
are fever, shortness of breath, fluid collection in the lungs, or decreased oxygen levels in the
blood. If the heart transplant is successful, the patient will have a new heart that works better 6.
TRANSCATHETER AORTIC VALVE REPLACEMENT (TAVR)
The heart is divided into four chambers: right atrium, right ventricle, left atrium, and left
ventricle. The heart also has four valves (tricuspid valve, pulmonic valve, mitral valve, and aortic
valve) to keep the fluid flowing in one direction by opening or closing during contractions. All
the blood from the veins enters the right atrium. When the atrium is full, the tricuspid valve
opens, and the blood flows into the right ventricle. The tricuspid valve closes and the right
ventricle contracts, pumping the blood into the lungs through the pulmonary artery as the
pulmonary valve opens. As the de-saturated blood passes through the lungs, carbon dioxide is
exchanged with oxygen. The oxygenated blood flows from the lungs to the left atrium when the
mitral valve opens. Then, the blood goes to the left ventricle and leaves the heart 1.
TAVR is a minimally invasive surgical procedure that repairs an old damaged
valve. TAVR expands the new valve over the old valve, similar to placing a stent in an artery. It
is performed on patients with severe symptomatic aortic stenosis, which is a narrowing of the
aortic valve opening because of plaque buildup. The new implanted valve pushes the old valve
out and the tissue in the replacement valve takes over the job of regulating blood flow 8. TAVR is
different than a standard valve replacement, although the purpose is similar. A standard valve
replacement requires an open heart surgery where the chest is opened. TAVR can be done
through small openings and is less invasive. This procedure is done for the people for whom an
open heart surgery is too risky because of their age or other medical conditions. This is usually
done on older individuals rather than younger individuals because the valve has to be replaced
every 8-15 years7. The valve used is called the Edward SAPIEN Valve, which is the only
transcatheter aortic valve currently used. The valve consists of three main parts: bovine
pericardial tissue leaflets, steel frame, and PET Skirt9. A surgeon can access the valve through
different approaches. The three different types of approaches are transfemoral approach
(through the femoral artery in the leg), transapical approach (in the chest), and transaortic
approach (upper chest). During the procedure, a balloon is guided to the valve, and inflated to
push the plaque out of the way and make space for the new valve. Another catheter is inserted
in that area with a valve around it and the valve will open up over the existing valve. The new
valve will take over the job of the old valve8.
ANGIOPLASTY
Angioplasty is done to treat coronary artery disease (CAD), which is caused by plaque
buildup in the arteries. CAD happens when arteries that supply blood to heart muscle becomes
hardened and narrowed due to the buildup of plaque. As the arteries get narrower, less blood
can flow through and the heart muscle does not get enough supply of oxygen. This can lead to
angina, or even heart attack. CAD can weaken the heart muscle and cause heart failure. This
procedure is done to open narrowed arteries and restore blood flow10. Doctors can tell if
someone has narrowed arteries by injecting a small amount of contrast liquid. This liquid is
photographed with X-ray as it moves through the heart's chambers and the doctors can tell by
looking at the photographs which arteries are blocked. Before the surgery, the patient will need
a blood test and electrocardiogram that shows the heart's electrical activity. Also the patient
cannot eat or drink before the surgery. The patient will also need aspirin to thin the blood 7.
There are several types of procedure used when performing angioplasty.
In a balloon angioplasty, a catheter with a balloon is inflated at the narrowed
artery. The inflation of the balloon compresses the plaque against the artery wall and stretches
the artery to increase blood flow. This procedure is not used very often because it provides only
a temporary solution11.
A stent is a small tube that supports the inside of the coronary artery. The balloon
catheter is sent to the narrowed artery. When the balloon is inflated, it expands the stent and
holds it up. The balloon is deflated and removed, while the stent stays there. The stent widens
the artery and increases blood flow. After the surgery, the patient will need to take plateletblocking medications to reduce the possibility of blood clot forming near the stent 11.
During the surgery the patient will stay awake. If the catheter was inserted through the
groin, the patient will have to lay flat for about six hours to prevent bleeding after the surgery.
Once the procedure is complete, the blocked artery will have a higher blood flow7.
CONCLUSTION
The four main types of surgeries researched were CABG, heart transplant, TAVR, and
angioplasty. CABG is performed on a patient when the patient has a blocked coronary artery
because of plaque buildup. A new vein or artery from a different part of the body is connected
from the aorta to the coronary artery below the blockage. A heart transplant is performed
when a patient has a damaged heart. The patient’s heart is replaced with a donor heart. TAVR is
performed when a patient has a narrowed valve because of plaque buildup. A new artificial
valve is replaced over the original valve. Angioplasty is performed when a patient has a blocked
artery. A balloon can be used or a stent can be placed in the narrowed region to widen the
artery. These surgeries are performed to increase blood flow and make sure the heart functions
efficiently.
REFRENCES
1. Boundless (2016). Boundless Biology. Retrieved from
https://www.boundless.com/biology/textbooks/boundless-biology-textbook/thecirculatory-system-40/mammalian-heart-and-blood-vessels-226/structures-of-the-heart851-12096/
2. What is Coronary Artery Bypass Grafting? (2012, February 23). Retrieved
from http://www.nhlbi.nih.gov/health/health-topics/topics/cabg#
3. John Hopkins Medicine Coronary Artery Bypass Grafting. Retrieved
from http://www.hopkinsmedicine.org/healthlibrary/test_procedures/cardiovascular/coron
ary_artery_bypass_graft_surgery_cabg_92,p07967/
4. Mueller, D. (2015, April 13). Heart Transplant. Retrieved
from https://www.nlm.nih.gov/medlineplus/ency/article/003003.htm
5. Fishbein, M. (2015, June 10). Heart Transplant. Retrieved
from http://www.medicinenet.com/heart_transplant/article.htm
6. John Hopkins Medicine Heart Transplant. Retrieved
from http://www.hopkinsmedicine.org/healthlibrary/test_procedures/cardiovascular/heart
_transp
7. Patel, T. Personal Communication. (2016, May 28)
8. What is TAVR?. (2016, May) Retrieved
from http://www.heart.org/HEARTORG/Conditions/More/HeartValveProblemsandDisease/
What-is-TAVR_UCM_450827_Article.jsp#.V1c5WvkrLIV
9. Transcatheter Aortic Valve Replacement. (2011, November). Retrieved from
http://www.harthosp.org/heart/TAVR/default.aspx
10. Coronary Artery Disease. (2014, September 11). Retrieved
from https://www.nlm.nih.gov/medlineplus/coronaryarterydisease.html
11. Beckeman, J. (2016, February 16). Heart Disease Treatment with Angioplasty and
Stents. Retrieved from http://www.webmd.com/heart-disease/guide/treatmentangioplasty-stents