Research Paper
Cardiovascular Disease Research
Mark O’Neal
Human body biology is the study of the human body and how its systems cooperate with and use one another to prosper and run effectively. The human body, though intricate and unique, is remarkably easy to study and effectively grasp and understand. The human body has a total of eleven different systems that work with each other to effectively run the human body. Of these eleven systems, there is the skeletal system, the muscular system, the cardiovascular system, the digestive system, the endocrine system, the nervous system, the respiratory system, the immune, or lymphatic system, the urinary system, the reproductive system, and the integumentary system. If one system is to fail, such as the cardiovascular system, the entire body and all of its systems would begin to drag and fail in a way that could be harmful to the body. The cardiovascular system in particular is one that has been undergoing study for hundreds of years. Starting in fourth century BC, Aristotle and Hippocrates began the first recorded scientific dissections on animals. Studying the anatomy of a creature and learning the basics of how it worked was the gateway to a broad horizon under which the human body could be studied. In the later fourth century BC, the first recorded human cadavers took place under the research of Herophilos and Erasistratus after they were granted permission to perform dissections upon the corpses of executed criminals in Alexandria. Studying the deceased criminals of the era gave the people of the time a brief understanding of how the human body functioned. They studied a lot of things, but one thing that was looked upon quite a lot was the cardiovascular system and how the heart equated to life in a human. After much research, in the second century BC, human dissection was banned and the research on the human cadavers was stopped. Once the study of human cadavers stopped, researchers were confined to studying pigs and apes. Because the anatomy of a pig is so remarkably similar to the human body, the research in a sense continued. In the fifteenth century Leonardo Da Vinci secretly restarted the research on the human body. He released anatomical pictures and descriptions of the human body and how he saw that it functioned. Leonardo Da Vinci did a lot of work on a lot of different cadavers, but he especially did a lot of work on the vascular system and the way that people can move. Human cadavers are still used today and are an effective an effective way to understand the human body, especially the cardiovascular system because it enables the studier to have a first hand look at exactly what’s happening with and what’s associated with the human heart. The cardiovascular system deals with the heart, veins and the blood vessels. It can influence the way that people are able to exercise and commit to physical activities, such as running. Since most exercises deal with the concept of endurance and getting your body running at near its peak, observations can be done to study the systems. Given the cardiovascular system deals with the heart, you can observe a persons heart rate after they commit to a bit of physical exertion. The American Heart Association deems that the best way to reduce any risk of a cardiovascular related disease is to stay physically active, thus making exercise something that could be valuable for research. There are tests however that reveal different things about the heart. Tests like the electrocardiogram (ECG) are tests that involve small probes that are taped to the chest to study the electrical impulses omitted by the heart. By studying the electrical output from a persons heart, you could begin to understand the way that the heart beats and you could determine what is regular, and what is irregular in terms of a normal and safe heartbeat. Though this is one effective and practical method for examination, there are a lot more that are used to study the human heart.
Below will be examples of different possible methods that are used to study the heart and how they work, and what they are able to tell, and how they relate to one another.
First is a non exercise method of heart monitoring. This test is mainly revolved around being a stress test, because it monitors the way your heart reacts after being given a medication to stimulate it. This method involves being given a medical stimulant that stimulates the heart in only a way that exercise would. This test, being an ECG test involves the usage of probes to monitor the activity of the heart. The medication that is directed into the body contains a large quantity of adrenaline. The human body releases adrenaline to help deal with a stressful ordeal. Once the adrenaline is put into the bloodstream, doctors are able to monitor the way that the heart deals with the new adrenaline. This test shows how the heart is able to cope with the adrenaline and recharge afterwards.
One disease, long QT syndrome is something that drastically affects the way that the heart palpitates and functions. One way that doctors are able to study this cardiovascular disease is by attaching electrodes to the head that measure small waves of electricity. This shows how neurological system could possibly affect the heart in such a way that could cause sudden collapse or fainting.
All of these methods of observation derive from the way to monitor for cardiovascular diseases, but they all offer unique and distinctive ways that the heart can be studied.
Cardiovascular disease encompasses a lot of different diseases that relate to the heart and cardiovascular system. There are a lot of different types of diseases that can be classified as cardiovascular diseases, some of which are; heart attacks, ischemic stroke, a hemorrhagic stroke, general heart failure, arrhythmia and general heart valve problems. A lot of different things can go wrong with the cardiovascular system if a disease appears. The cardiovascular system is highly influential upon the other systems in the body, and having a major failure in this system can lead to a drastic snowball effect upon the entire body that could easily lead to permanent disabilities or death. Because the body is so dependent on the heart to function correctly, catastrophic failure of the human body could be presented with cardiovascular disease. Because of all the different types of cardiovascular diseases, the body could fail in numerous fashions if in event of a cardiovascular disease. The most common and well known cardiovascular disease is the heart attack. The heart attack is caused when a plaque buildup in arteries around the heart begin to clog and can’t allow for oxygen rich blood to pass through to be pumped. In the arteries around the heart, plaque buildup is a normal thing. Having a small amount of plaque is okay because it doesn’t accumulate into much if broken, but having a large amount can be deadly. If the plaque in the artery were to break, it would be sent through the blood vessel and blood would begin to clot to it. Having a blood clot is a terrible thing because it doesn’t allow a complete flow of blood throughout the body and it might cause a metaphorical traffic jam in the veins or arteries. Too much blood clotting could lead to a possible rupture, but that will be covered a little later. Once the blood clots, the heart begins to receive less and less useful, oxygen rich oxygen. Once the heart begins to be deprived of oxygen, it starts to beat erratically and starts dying. The heart is required to pump blood with oxygen throughout the body, but being a muscle itself, it needs the oxygen, too. Being oxygen deprived, the heart begins to literally die and after a certain amount of time it will shut down due to loss of oxygen. If the heart is able to survive the initial attack and lives to see another day, it will be riddled with scar tissue that makes it weaker than it was before. If the heart is weaker, it is slightly more susceptible to damage and it becomes slightly more prone to failure than before. A heart attack is a bad thing, but the long term effects are just as bad, if not in some cases worse. Possible long term effects include arrhythmias, cardiogenic shock and general wear and tear. Arrhythmias is an irregular beat that persists in the heart that could accelerate to a point where the heart is working too hard, or it could make it beat too slow to function effectively. Cardiogenic shock is a decrease in blood pressure that makes it harder for the heart to pump the blood that it is given. Among these long term effects, the heart’s damage is what makes it hardest for it to function correctly. Having a decreased blood pressure means that the blood coursing throughout the body is moving at a slower speed than normal, thus making it so vital organs are not getting the required amount that they need. Having low blood pressure can affect most major organs. The brain runs off the oxygen delivered by the blood, and having a low blood pressure starves the brain of the oxygen that it requires which could lead to neurological damage and other brain damage. When the brain is starved of oxygen, it begins to struggle to function correctly and that can lead to dizziness, light headedness and a loss in ability to pay close attention to things. Once escalated to a state where the brain desperately requires blood, the brain begins to take damage to certain parts. Once the brain begins to take damage, it leads to a stroke. A stroke occurs when brain cells suddenly die due to lack of oxygen. Having the brain take damage can lead to a lot of different effects. Things that can happen after a stroke are losing the ability to speak, loss of memory and paralysis. These things occur because the brain is losing vital cells to keep it healthy and alive thus making certain things extremely difficult or impossible. Because of the brain’s dire need for oxygen, a deprivation of it leads to huge consequences that can all lead back to the heart attack.
Low blood pressure caused by heart attacks can also lead to the failure of other vital organs, like the kidneys. The kidneys naturally influence the blood pressure in a human’s body by secreting renin. Renin is a chemical that helps the body to regulate a safe and health blood pressure. Because the kidney’s are not receiving as much blood oxygen as required, they begin to produce less renin which leads to long term low blood pressure.
Aside from heart attacks, there are other forms of cardiovascular diseases that can lead to a catastrophic chain of events. Another cardiovascular disease that can cause a huge failure is the ischemic stroke. An ischemic stroke is when an artery in the brain becomes clogged and the brain cannot receive an ample amount of oxygen. Once the brain fails to receive oxygen, neurons begin to stop firing and then certain parts of the brain begin to shut down. Ischemic strokes are the most common forms of strokes and they are extremely deadly and effective in dealing massive damage to a person. Neurological damage can take place if the brain is not functioning for an extended period of time, and the long term effects can be crippling. By damaging the neurological system, you risk damaging parts of the brain that influence movements and other common acts, like speech.
Another type of stroke that largely affects the brain is the hemorrhagic stroke. A hemorrhagic stroke is when a blood vessel in the brain begins to clot, but instead of the usual backup and normal clotting, it ruptures and displaces blood into the brain causing pile ups of blood in parts of the brain where it doesn’t belong. The hemorrhagic stroke begins its life as an aneurysm where the blood vessel contains too much blood and begins to act as a balloon and inflates. The hemorrhagic stroke then happens when the pressure becomes too intense and the blocked vessel bursts to release the blood throughout the brain. Once the brain is omitted into the brain, serious effects begin to set their course. Once the blood gets into the brain, a massive headache kicks in and then you start to feel a sudden weakness or numb feeling on one or both sides of your body, difficulties understanding language, difficulties speaking or problems seeing. When a cardiovascular disease hits the body, nothing is safe because of how the effects influence other parts of the body.
Cardiovascular diseases can also influence blood clots. Blood clots are usually a good thing because they help our body to recover from wounds that yield in blood loss. A blood clot is when blood platelets accumulate and create a figurative plug that stops from more bleeding that can allow for the tissue to recover and fix the wound for good. A blood clot can go bad, however. When the blood in a vessel begins to clot around something that doesn’t belong, such as plaque, it creates a backup that can lead to a vessel rupture or a huge decrease in blood pressure.
Having a low blood pressure can be seriously detrimental to the body, but how about a high blood pressure?
High blood pressure is when the heart is able to pump more blood, faster. More blood being pumped may be good, but not when the blood pressure becomes too high. Once the blood pressure increases to an unusual amount, it begins to pump the blood too fast. If blood in the body goes too fast, it can strike against the vein walls too hard and create a chance to cause a heart related deficiency. When your blood pressure rises, the arteries become slightly more narrow and that allows the blood to flow smoothly through. Having a high blood pressure isn’t immediately bad, but over time it can wear the vein walls down to a point where they are especially weak which increases the risk of a rupture, heart attack or stroke.
Coronary heart disease is another disease that affects the cardiovascular system. Coronary heart disease is the buildup of plaque in the coronary arteries. The coronary arteries are the most popular passage for blood to get to the heart. The heart requires the coronary arteries to be clean and easily traversable, so the buildup of plaque in them can be deadly. The accumulation of plaque in the coronary arteries makes the arteries narrow and less active, thus increasing the risk of other heart diseases. With CHD, the flow of blood through the coronary arteries can become extremely slow, or it can entirely stop. Either way, not having a sufficient amount of blood to the heart can quickly lead to a heart attack which can cause even more difficulties throughout the body.
With CHD, the chances of a heart attack are quite high. After a heart attack, the heart becomes extremely weak. A disease that can set in after heart attacks or on somebody that is unhealthy is cardiogenic shock. Cardiogenic shock is when the heart begins to lose power and it becomes too weak to effectively pump blood throughout the body. A shock is when the body is unable to pump the required amount of blood through the body and it becomes starved of oxygen thus damaging certain body parts. Cardiogenic shock is quite common after the heart takes a massive hit like a heart attack, and cardiogenic shock can be quite deadly itself. Cardiogenic shock is when the heart is unable to pump enough blood throughout the body because of damage. Not having enough oxygen coursing throughout the body is an extremely deadly factor. The human body is largely comprised of muscles and muscle tissue that depends on oxygen and fresh blood to keep it healthy and well. Cardiogenic shock doesn’t allow the heart to pump oxygen rich blood through the body and that deprives muscles of their required oxygen thus making a person weaker than before. Prolonged exposure to cardiogenic shock can be fatal because the body begins to suffocate from lack of good oxygen being sent from the heart. Because of the decrease in blood pressure, not enough oxygen is being sent. With the shock comes the risk of a vasodilatory shock. The vasodilatory shock is when the vascular system dilates and the amount of blood being pumped largely increases which lowers the pressure of blood.
On top of all these other cardiovascular diseases, the heart can simply take damage and fail all around if weakened. Heart failure is most commonly referred to as congestive heart failure where the heart muscles fail to effectively pump the blood as well as is needed. Narrowed arteries, or coronary or artery diseases, or high blood pressure can gradually leave your heart too weak or too stiff to fill and pump efficiently.
Not having your heart be able to beat the blood correctly is bad, but even when it is able to pump the blood right, there is still risk for failure. The heart needs to stick to a certain rhythm to be able to pump blood effectively through the body. The rhythm changes depending on the amount of physical exertion is being done. Though the heart is good at keeping a normal, safe and effective rhythm, there is still a chance for failure. One disease, arrhythmia, is when the heart’s beat is too irregular and begins to cause problems. The heart can begin to beat too fast, which is known as tachycardia, or it can begin to pump too slow, which is called bradycardia. The heart can also suffer from premature contraction or it can begin beating too irregularly to function correctly. Fibrillation is when the heart begins beating erratically. Fibrillation can cause palpitations, dizziness, exercise intolerance, fatigue, chest pain, and dyspnea. Having these things happen can seriously damage the heart, and in some cases can lead to it shutting down on a person which is a large factor in heart disease related deaths. Fibrillations can lead to a decrease in physical ability and breath because they don’t allow for the heart to pump blood effectively and safely. The heart begins to go on a sort of a rampage when fibrillating, and one way to stop this is with defibrillators. They send a shock of electricity through the heart that essentially restarts it and gets it working normal again. Though most cases of arrhythmia are harmless, some can cause extreme damage to a persons heart and in turn lead to blood pressure fluctuations that can ultimately lead to death or permanent change.
One more thing that can be classified as a cardiovascular disease is a heart valve failure. A heart valve failure is where one or more heart valves don’t work effectively. With each heartbeat, tissue flaps open and close which allows for flow of blood in the right direction of the body. Heart failures can begin to take place within the heart valves because the heart valves have such a momentous task. In some cases, people with a heart valve failure have valves that don’t close tightly enough and in turn cause a leak of blood back into the chambers rather than into an artery as intended. Heart valve failure doesn’t usually lead to anything major, but in some cases it can contribute to the formation of general heart failure, strokes, blood clots or even sudden death due to cardiac arrest.
All of these things can easily develop into a life threatening situation if not treated properly, but on top of them all, the most deadly is sudden death by cardiac arrest. A cardiac arrest is when the heart simply stops beating. This leads to an absolute stop of blood pumping and stops the circulation of oxygen through the body. This affects the muscular system, the nervous system, the circulatory system, and sometimes it can affect all of the systems by leading to sudden death.
Research on the human cardiovascular system is great and ever expanding. Though medical students and a lot of professional doctors still study on the lifeless cadaver, a lot of electric measuring devices are being used to better understand the way that the heart functions. Using electrical measuring devices gives an understanding of how the heart functions under stressful encounters and is able to give doctors an idea on what is happening when the heart functions. To better understand cardiovascular diseases in general, doctors have begun to study the people that have reported having cardiovascular related diseases. By studying a person with a disease, you can better understand the way that the disease works because it shows you what is happening when the body malfunctions.
There are a lot of different medicines that can be used to cure the disease. Therapies can include exercises and healthy eating because these two things reduce the risk of people getting clogged arteries which can help to reduce the risk of heart attack and stroke. Because a few diseases include the clotting of blood, blood thinners are used to reduce the risk of blood getting clotted together to create a jam that could lead to other serious side effects.
Other methods of prevention include beta blockers. A beta blocker is a medicine that reduces heart rate and blood pressure which lowers the chances of a heart attack or stroke. Unfortunately, people who already have a lower blood pressure, asthma and a lower heart rate are unable to take this because it would lower their heart rates and vital signs to a dangerous low that could lead to a higher chance of death than if you weren’t to take the medications. Another method is known as Angiotensin-converting enzyme (ACE) inhibitors. Doctors prescribe ACE inhibitors for most people after heart attacks, especially for those who have had a moderate to severe heart attack that has reduced the heart's pumping capacity. These drugs allow blood to flow from your heart more easily. Finally, there are cholesterol lowers that lower the amount of cholesterol in the blood stream which reduces the risk of a blood clot.
Contacts:
Assad Mora
Cardiologist
San Diego, California 92123
858-279-4879
Charles Athill
Cardiologist
San Diego, California 92123
858-499-5150
Martin Charlat
Cardiologist
Encinitas, California 92024
760-633-6501
Richard Osborne
Cardiologist
San Diego, California 92120
619-528-3920
Ajit Raisinghani
Cardiologist
San Diego, California 92103
619-543-5743
Denise Hermann
Cardiologist
San Diego, California 92103
619-543-6768
Manish Wadhwa
Cardiologist
San Diego, California 92103
619-294-8111
Bruno Cotter
Cardiologist
San Diego, California 92103
619-543-5743
Anthony Demaria
Cardiologist
San Diego, California 92103
619-543-6222
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