Essay: Marfan syndrome

ABSTRACT
Marfan syndrome is a systematic disorder of connective tissue caused by mutations in the FBN1 gene, causing complications outside and within the body (Judge and Dietz, 2005). Although several systems are disturbed by Marfan syndrome, the cardiovascular system is the most important one affected. The body structure includes many veins and arteries, but among them is one of the most vital organ of all, the heart. In fact, obstruction of the heart and ateries proves to be the most common cause of death to Marfan syndrome patients, most likely due to the weakened aorta which is a major blood vessel. Approximately 1 in 5000 individuals obtain the disease, either inherently or spontaneously. It is important to recognize this disorder quick before it creates fatal effects to the body, which is why many Marfan syndrome patients attend regular checkups to evaluate their x-rays. This report will give further insight on what Marfan syndrome is and the process of this life-threatening disease, including descriptions of the symptoms and appearances that can be expected of those who are diagnosed with Marfan syndrome. Along with that, information on how Marfan syndrome affects the body and overall health of the patients will be explored, with a stronger emphasis on the cardiovascular system (which will be reviewed on). Techniques of diagnosis and treatment are also provided.
WHAT MARFAN SYNDROME IS
Marfan syndrome is a genetic disorder that has an effect on the connective tissue in the body (Dormand and Mohiaddin, 2013). The disorder is named after Antoine-Bernard Marfan, a Parisian professor of pediatrics, who first described the syndrome on a 5 year old girl with disproportionality long limbs and fingers (Dormand and Mohiaddin, 2013). The disorder is caused by mutations in FBN1 gene, which produces the fibrillin 1 protein of the tissue, a ‘building block for connective tissue in the body’ (Haldeman-Englert, 2012). Along with providing structural support, the fibrillin 1 protein also interacts with a protein called transforming growth factor beta (TGF-??). As a result, the mutated fibrillin 1 protein excessively signals and activates TGF-?? proteins, in which increased amounts of TGF-?? occur (Braverman 2009). This causes problems in the connective tissue all throughout the body and interferes with numerous bodily systems, including the cardiovascular system. Marfan syndrome occurs in about 1 out of every 5,000 individuals worldwide, with 3 out of 4 Marfan patients inheriting the disorder. Although the chances of inheriting the disorder are high, some people are able to be the first of the family to acquire it. This is also known as a spontaneous mutation (‘What is Marfan Syndrome’?, n.d., para. 1-5).
CHARACTERISTICS OF MARFAN SYNDROME PATIENTS
One of the most prominent symptoms of Marfan syndrome is the patient’s physical appearance. Marfan syndrome patients are usually very tall and thin with long, willowy limbs and fingers. Their limbs are so disproportionally long that when they stretch out their arms, it is indeed greater than their height. Along with that, they may have a chest that caves in or out (Haldeman-Englert, 2012). They also suffer from severe scoliosis. Not only is their outward appearance affected, their internal organs also experience the syndrome. It causes cataracts to the eyes and dislocation to the lenses. Lung tissue is vulnerable to pneumothorax, a process where air escapes from the lung and goes into the chest cavity which ultimately causes the collapse of the lung (Haldeman-Englert, 2012). The aorta is another major organ that is affected by Marfan syndrome. It suffers from an aortic dilation or an aortic aneurysm, where it broadens and becomes fragile, an unfavorable thing for a main blood vessel to endure (‘What is Marfan Syndrome’?, n.d., para. 8-9). Like mentioned before, due to the mutated FBN1 gene, excessive amounts of proteins are present in Marfan syndrome. This defect causes too much bone growth in the body, which is the reason behind the tall stature of Marfan syndrome patients (Haldeman-Englert, 2012).
OVERALL HEALTH OF MARFAN SYNDROME PATIENTS
Although heart-related complications may shorten the lifespan of Marfan syndrome, many patients survive well into their 60s. Modern surgery techniques and good health habits may even extend the lifespan (Haldeman-Englert, 2012).
THE CARDIOVASCULAR SYSTEM
Another way to describe Marfan syndrome is that it’s a multi-system disorder. And while it typically involves the skeletal and ocular system, one of the most important systems affected is the cardiovascular system. This system contains capillaries, veins, arteries, and a heart (Vorvick, 2013). What makes this network of veins and arteries so crucial to the human body is that it’s responsible for transporting blood rich in nutrients and oxygen to the body’s cells and getting rid of the waste that is released by those cells. That is why it is very critical having Marfan syndrome obstruct this process.
THE CAPILLARIES
Capillaries are very tiny, thin-walled blood vessels that serve as a bridge between the arteries and veins. Its thin walls permit oxygen and nutrients to transfer from the blood into the tissues and waste to pass from the tissues into the blood (Shea, 2013).
THE VEINS
Although they play a major role in the circulatory system (perhaps even making up the whole system), veins contribute well to the cardiovascular system. They share some of the same characteristics except they carry blood at a lower pressure. They are made up of three layers: tissue on the outside, a middle layer of muscle, and on the inside, a layer of epithelial cells (‘Veins: All in Vein’, n.d., para. 1). Spanning throughout the whole body, the veins’ main goal is to return blood back to the heart and lungs. After exchanging oxygen for carbon dioxide with the capillaries using its very small venules, it takes the waste-filled blood back to the heart to prevent the unclean blood to flow backwards. Luckily, the veins are accompanied by vein valves, which act like gates while only allowing the blood to move in the proper direction. They are also necessary to keep blood moving toward the heart since they allow the blood to travel in the opposite direction of gravity (i.e. blood flowing upwards from the leg to the heart) (Veins: All in Vein’, n.d. para. 3). If veins didn’t have this advantage, then it would make things very difficult, especially when trying to bring blood to the brain, saving it from causing the body to faint. Unfortunately, those helpful valves could be ruined by Marfan syndrome, having the veins and cardiovascular system hard to adjust (‘Veins: All in Vein’, n.d., para. 1-4).
THE ARTERIES
Like veins, arteries are made up of three layers: tissue on the outside, muscle in the middle and an inner layer of smooth epithelial cells for the blood to flow easily. The arteries are in charge of delivering oxygenated blood from the heart to the capillaries. They begin from the aorta and are branched out to form even smaller versions, called arterioles, which are connected to the capillaries (‘Arteries: Arteries Carry Away’, n.d., para.1-5). Since the blood pressure in them is high, both the arteries and arterioles have thick muscular walls that alter their diameter to decrease or increase blood flow to different destinations of the body (Shea, 2013). The heart also gets its own supply of blood the coronary arteries. These two arteries branch off from where the aorta and the left ventricle meet (‘Your Coranary Arteries’, n.d., para. 1). The right coronary artery mainly provides blood flow to the right side of the heart, where it will pump into the lungs (‘Your Coronary Arteries’, n.d., para. 4). The left coronary artery supplies the circumflex artery, a part of the circulatory system that distributes blood to the left atrium and side and back of the left ventricle (‘Your Coronary Arteries’, n.d., para. 1-6). The main artery (and the largest) is the aorta. It carries oxygen-rich blood from the left ventricle of the heart to other parts all throughout the body (‘Aorta Anatomy’, n.d., para.1). As the aorta rises from the left ventricle and curves behind the right atrium, it crosses over the pulmonary arteries and descends behind the heart towards the abdomen, aligning itself along the front of the spine (‘Aorta artery – definition and function’, n.d., para.1-2). Being the main artery responsible for transporting blood from the heart, having complications concerning the aorta is highly dangerous and it is understandable why Marfan syndrome should be taken very seriously.
THE HEART
The heart is one of the most important organs the body contains. Its only goal is to pump blood necessary for survival. The heart has four chambers: the upper right atrium, the lower left atrium, the upper right ventricle, and the lower left ventricle (‘How the Healthy Heart Works’, American Heart Association, 2012). Separating the chambers is a wall of tissue called the septum. Also accompanying the chambers are four heart valves: the tricuspid valve (between the right atrium and right ventricle), the pulmonary valve (between the right ventricle and the pulmonary artery), the mitral valve (between the left ventricle and the left atrium), and the aortic valve (between the left ventricle and the aorta) (‘How the Healthy Heart Works’, American Heart Association, 2012). The valves open and close, only allowing blood to flow in one direction, using a set of flaps, or cusps. The mitral valve is the only one out of the four valves that has two flaps, the rest has three (‘How the Healthy Heart Works’, American Heart Association, 2012). The right side of the heart pumps blood intended for the lungs, where it adds oxygen to the blood and removes the carbon dioxide from it (‘What Does Your Heart Look Like and How Does It Work’?, 2012). The left side of the heart takes care of pumping blood to all of the body, where it delivers the required oxygen and nutrients to the tissue and waste products are transferred to the blood for removal from other organs (‘What Does Your Heart Look Like and How Does It Work’?, 2012). To be more specific, the right atrium gets de-oxygenated blood from the rest of the body and the right ventricle collects the blood from the right atrium and then pumps the blood into the pulmonary arteries which then delivers the blood to the lungs for oxygenation (‘The Cardiovascular System’, n.d., para. 5). The pulmonary arteries then pumps the newly oxygenated blood from the lungs to the left atrium. Finally, the left ventricle contracts and forces the blood throughout the aorta and around the body, where it continues the ongoing cycle (‘The Cardiovascular System’, n.d., para. 4-5).
EFFECT OF MARFAN SYNDROME ON THE CARDIOVASCULAR SYSTEM
According to Judge and Dietz, authors of the journal ‘Marfan’s syndrome’, ‘Manifestations of Marfan syndrome in the cardiovascular system are conveniently didvided into those affecting the vasculature.’ (Judge and Dietz, 2005) Vasculature is also referred as the arrangement of blood vessels in the body, or the circulatory system.
EFFECT ON THE HEART
Atrioventricular valves (the mitral and the tricuspid) within the heart are most often affected. It usually thickens, and is often associated with the prolapse of either one of the two valves, or both. A prolapse of the valves means that one or all the flaps of the valves are enlarged, and the flaps’ supporting cords (called chordae tendineae) are longer than usual (‘Marfan Syndrome’, Texas Heart Institute, 2013). Instead of closing evenly, the flaps collapse or bulge into the atriums. These prolapses can be classified as a click-murmur syndrome because when the valve doesn’t close correctly, it makes a sound close to a click and then later murmurs (due to blood leaking backward into the valve). Varied degrees of regurgitation may be present. As referenced in ‘Marfan’s syndrome’ by Judge and Dietz (2005), ‘Insufficiency of the mitral valve can lead to congestive heart failure, pulmonary hypertension, and death in infancy’ (Judge and Dietz, 2005). In association with mitral valve dysfunction, people affected with Marfan syndrome are also vulnerable an abnormal heart rhythm (arrhythmia) (‘Marfan Syndrome’, Texas Heart Institute, December 2013).
EFFECT ON THE VASCULATURE
Weakening of the walls of the major arteries are some of the side effects that come with Marfan syndrome. Along with the heart, the main artery connecting it is also affected, the aorta. When the aorta is affected, it dilates and gets weaker (‘Marfan Syndrome’, December 2013). Judge and Dietz (2005) states that ‘Aortic aneurysm and dissection remain the most life-threatening manifestations of Marfan syndrome’ (Judge and Dietz, 2005). Aortic aneurysm occurs when the weakened area of the aorta bulges outward. Like a balloon, the aneurysm expands and the wall of the artery gets thinner, increasing the chance that it will tear. The most common spot for an aortic aneurysm to occur is in the segment where the aorta runs through the abdomen. The second most common place for it to occur is where the aorta lies close to the heart. (‘Aorta Disease & Marfan Syndrome, 2012). An aortic dissections occurs when the inner aortic wall tears. This tear leads to blood leaking into and along the wall of the aorta, possibly starting a bulging aneurysm. Two channels are created due to a tear, in which one still allows blood to move and another in which the blood is immobile (Dugdale, 2012). The channel with the non-traveling blood increases in size, pushing onto to the other branches of the aorta. This action narrows the braches and reduces the blood flow in them. By reducing blood flow in the cardiovascular system, it certainly proves to be a fatally severe problem (Dugdale, 2012). Marfan syndrome also takes a toll on the aortic valve. For some with the disorder, blood leaks backwards within the valve instead of the correct, onward direction. This is otherwise known as regurgitation (‘Marfan Syndrome’, Texas Heart Institute, 2013). Due to the backwards flowing blood, only a small amount of blood can properly travel to the body’s organs. This causes the heart to work harder, which could lead to it becoming enlarged, making it not able to pump blood efficiently (‘Marfan Syndrome’, 2013).
TECHNIQUES FOR DIAGNOSING MARFAN SYNDROME
Throughout the years since Marfan syndrome had been first introduced, various medical advancements have been created. Thanks to this, many people with the condition have an increased chance of living a longer, quality life. Many who are treated in time are able to live an average lifespan, perhaps even longer. (‘What Is Marfan Syndrome’?, NHLBI, 2010).
ECHOCARDIOGRAPHY
After visiting specialists that focus in the relevant fields that Marfan syndrome falls under (for example an orthopedist, geneticist, and a cardiologist), one would then undergo numerous examinations and tests. Echocardiography is an assessment that utilizes sound waves to create images of the heart and blood vessels. It displays the appearances of the heart along with the width of the vital blood vessels (including the aorta) (‘What Is Marfan Syndrome’?, NHLBI, 2011). It can also pinpoint areas of the heart that are not functioning well due to poor blood flow or previous injury. A type of echocardiography is a Doppler ultrasound, which shows how well blood flows well blood flows through your chambers and values. This test is important for Marfan syndrome patients since it detects possible blood clots, fluid buildup in the pericardium, and problems with the aorta (‘What is Echocardiography’?, 2011). According to the authors of ‘Cardiovascular Magnetic Resonance’, Dormand and Mohiaddin (2013), ‘As our understanding of MFS has grown, the assessment and monitoring of biventricular function per se should be part of our assessment, with tissue Doppler imaging incorporated into any protocol used,’ (p. 13). The diagnosis of aortic dissection using echocardiography requires demonstration of a dissection flap separating true and false lumens (Dormand and Mohiaddin (2013). Doppler imaging may be colored to show differentiating flows on either side of flap since more than one inner tear may be present. Dormand and Mohiaddin (2013) also found that ‘the assessment of aortic valve competency,’may help guide surgical intervention’ (Dormand and Mohiaddin, 2013, p. 13).
COMPUTED TOMOGRAPHY SCANS
Computed tomography scans (CT), according to Dormand and Mohiaddin (2013), ‘is one of the longest serving imaging modalities in the assessment of aortic disease’ (Dormand and Mohiaddin, 2013). During this process, the aid of an x-ray is used to take clear evaluations of the heart and aorta. Although CT scans possess the ability to accurately allow rapid diagnosis of an affected patient, it emits ionizing radiation. Thus, it is not suited for a long term use. (Dormand and Mohiaddin, 2013).
MAGNETIC RESONANCE IMAGING
This test uses magnets and radio waves to generate thorough pictures of the body’s organs. Magnetic resonance imaging (MRI) is painless and usually is requested when more information is needed after echocardiograms or CT scan. Cardiovascular magnetic resonance imaging (CMR) is referenced in the journal article,’Cardiovascular Magnetic Resonance in Marfan Syndrome’, by Doramand and Mohiaddin (2013) as ‘ ‘ not limited by acoustic windows and is free from losing ionizing radiation. The entire aorta can be imaged and complications including aneurysm formation, dissection, and previous surgery are well visualized. This makes it ideal for long-term follow up of patients’ (Dormand and Mohiaddin, 2013). Through CMR, information on the anatomy can be gained, like how intimal tears originated. CMR also has an equivalent level of the accuracy and sensitivity compared to CT scans for the analysis of aortic dissection, and is even more accurate when the probability is already known to be high before the test (Dormand and Mohiaddin, 2013). It has also been deemed the superior one compared to echocardiography when it comes to demonstrating asymmetrical root dilation. (Dormand and Mohiaddin, 2013).
GHENT CRITERIA
Marfan syndrome can be hard to diagnose since many of its traits are similar to other tissue connectivity disorders (‘How Is Marfan Syndrome Diagnosed’?, NHLBI, 2010). That is why doctors might turn to guidelines called Ghent criteria. It is divided into two criteria: major and minor. Traits common among Marfan syndrome sufferers belong under the major criteria. Minor criteria qualities are common in a lot of people (‘How Is Marfan Syndrome Diagnosed’?, NHLBI, 2010). Doctors evaluate the patient by referring to the number of either major or minor criteria present. Genetic testing is sometimes included to help diagnose the patient. (‘How Is Marfan Syndrome Diagnosed’?, NHLBI, 2010).
TREATING MARFAN SYNDROME
Unfortunately, Marfan syndrome does not hold a cure. However early treatments has a chance to prevent health obstacles. And since Marfan syndrome can affect numerous parts of your body, the patient’s signs and symptoms will determine what type of treatment to use on them (‘How Is Marfan Syndrome Treated?, NHLBI, 2010).
MEDICINE
Beta blockers are medications used to prevent further enlargement of the aorta and treat high blood pressure. It is also an essential part of cardiovascular health management. (‘Marfan Syndrome’, 2009). They ease stress on the aorta and delay the process of aortic dilation by helping the heart beat slower and easier. They are also supported by studies that demonstrate the blocking of the TGF-beta protein may help avoid Marfan syndrome symptoms, especially internally. (‘How Is Marfan Syndrome Treated’?, NHLBI, 2010).
SURGERY
To prevent aortic dissection, surgery may be recommended surgery to replace or repair a part of the aorta. A composite valve graft is where the aortic valve and a portion of the aorta are taken out. An artificial tube (known as a gaft) then replaces the aorta (‘How Is Marfan Syndrome Treated’?, NHLBI, 2010). The valve is exchanged for a synthetic valve. If the aortic valve stays working fine, then one would undergo aortic valve-sparing surgery. The valve is left untouched as the enlarged aorta is replaced with a graft. Blood thinners are later prescribed to prevent blood clotting on the man-made aortic valve. The patient will have to take this medication for as long as they live, unless valve-sparing surgery was partaken in. Another risk that comes with composite valve graft is endocarditis, which is where the lining of the heart valves and chambers experience an infection (‘How Is Marfan Syndrome Treated’?, NHLBI, 2010).
LIFESTYLE
Typically, a Marfan syndrome attends regular checkups which includes visits to the cardiologist, yearly checkups with a bone specialist, or orthopedist, to look for spine or breastbone complications, and consistent eye exams to search for or treat eye problems early (‘Living With Marfan Syndrome’, NHLBI, 2010). Along with the repeated checkups, patients must follow some guidelines for a healthy lifestyle. Smoking is not advised since it increases the risk of lung problems, something that Marfan syndrome patients are already vulnerable to. They also need to avoid strenuous physical activity (i.e. weightlifting and skiing) and sports that involves a hard ball or physical contact with other players (i.e. football or basketball) considering that it puts more strain on the heart. But light to moderate impact activities (i.e. golf or hiking) are suggested if one wants to engage in physical activity. The level of physical activity depends on the severity of the Marfan syndrome. Pregnancy is another factor to consider when concerning health risks that come with Marfan syndrome (‘Living With Marfan Syndrome’, NHLBI, 2010). While many pregnant women with Marfan syndrome experience safe and normal pregnancies, they still face the issues of aortic dissection (since pregnancy puts extra strain to the heart) and passing the gene of Marfan syndrome to their offspring. They possess a 50% of forwarding their ailment to each offspring they have. It is important to consult with a geneticist, cardiologist and an obstetrician prior to pregnancy to be informed of the risks associated with the mother and baby along with the possible options she can choose ‘Living With Marfan Syndorme’, NHLBI, 2010).
CONCLUSION
In conclusion, Marfan syndrome is a serious condition that involves alteration of the body’s vital systems, especially the cardiovascular system. In fact, the effect it has on the heart and contributing blood vessels prove to be one of the most fatal outcomes Marfan syndrome has on the patient. And with 1 out of every 5,000 people getting affected by it, it is important that doctors diagnose and evaluate the disease through special techniques involving machinery like echocardiograms, CT scans, and MRIs. And with the help of further medications and treatments, a Marfan syndrome patient is able to live a quality life with an average lifespan. Not to mention, researchers continue to study Marfan syndrome and develop better treatments. (‘What Is Marfan Syndrome’?, NHLBI, 2010).
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