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Aortic valve disease



Cardiovascular system


Vascular disorders
Congenital heart defects
Cardiac arrhythmias
Valvular disorders
Heart failure
Cardiac infections
Pericardial disorders
Cardiac tumors
Cardiovascular system pathology review

Aortic valve disease


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High Yield Notes
15 pages

Aortic valve disease

26 flashcards

USMLE® Step 1 style questions USMLE

5 questions

A 35-year-old man with Marfan syndrome presents with exertional dyspnea and pounding headaches for several months. His temperature is 37.0°C (98.6°F), pulse is 90/min, and blood pressure is 135/85 mmHg. On physical examination, the lungs are clear to auscultation. Cardiac auscultation reveals the murmur demonstrated below over the right sternal border. Palpation of the radial arteries shows a rapidly rising and falling arterial pulse. Which of the following is the most likely diagnosis?


External References

Content Reviewers:

Rishi Desai, MD, MPH

The aortic valve is typically made up of three leaflets: the left, the right, and the posterior leaflet and it opens during systole to allow blood to be ejected to the body. During diastole, it closes to allow the heart to fill with blood and get ready for another systole. If the aortic valve doesn’t open all the way, it gets harder to pump out to the body and this is called aortic stenosis. If it doesn’t close all the way, then blood leaks back into the left ventricle called aortic valve regurgitation or aortic insufficiency.

Usually, the aortic valve opens to about 3-4 cm2, but with stenosis it can become less than 1 cm2. This is usually caused by mechanical stress over time, which damages endothelial cells around the valves, causing fibrosis and calcification, which hardens the valve and makes it more difficult to open completely. This type usually shows up in late adulthood, with patients over 60 years old.

Similarly, patients that have a bicuspid valve — with two leaflets — as opposed to a tricuspid — with three — are more at risk of fibrosis and calcification because the mechanical stress that’s usually distributed between three leaflets is now being split by two leaflets and therefore, they see more stress per leaflet. Another important cause of aortic stenosis is chronic rheumatic fever, which can cause repeated inflammation and repair, leading to fibrosis. In this case, the leaflets can actually fuse together — called commissural fusion — which is an important distinction from the type caused by mechanical stress over time.

When the valve fuses together or hardens, it doesn’t open as easily, right? And so as the left ventricle contracts, it creates this high pressure that eventually pushes on the valve until it finally snaps open, causing a characteristic “ejection click.” Since the blood has to flow through a narrow opening, there’s turbulence which creates noise, or a murmur, which gets initially louder as more blood flows past the opening, and then quieter as the amount of blood flowing subsides because less remains in the ventricle. This is called a crescendo-decrescendo murmur.

Since now it’s harder to open and push blood past this hardened valve, the left ventricle has to generate higher pressures each time it contracts to get the same amount of blood through. To accomplish this, the left ventricle can thicken its muscles, called concentric left ventricular hypertrophy. This happens because new sarcomeres are added in parallel to the existing ones.

Even though you have this bulked-up ventricle, the heart still might struggle to get enough blood through the narrowed opening and to the body, and ultimately to the vital organs. And that means that the person’s at risk of developing heart failure, and various symptoms related to whichever organ is involved.

For example, if there’s a reduction in blood flow to the brain, it could lead to syncope. And a reduction in blood flow through coronary arteries to the heart’s own myocardium could cause chest pain and angina. Patients might not initially experience symptoms at rest, only during exercise, because exercise requires more blood, right? And this heart isn’t able to increase blood flow through this small opening.

A final complication is called microangiopathic hemolytic anemia, which is essentially damage to red blood cells as they’re forced through the smaller valve, splitting them into smaller fragments called schistocytes leading to hemoglobinuria, which is hemoglobin in the urine. Treatment is usually replacement of the valve, which often doesn’t happen until after the onset of symptoms.

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  2. "Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2)" McGraw-Hill Education / Medical (2018)
  3. "Pathophysiology of Disease: An Introduction to Clinical Medicine 8E" McGraw-Hill Education / Medical (2018)
  4. "Aortic Stenosis: Pathophysiology, Diagnosis, and Therapy" The American Journal of Medicine (2017)
  5. "Medical Treatment of Aortic Stenosis" Circulation (2016)
  6. "Aortic Valve Sparing in Different Aortic Valve and Aortic Root Conditions" Journal of the American College of Cardiology (2016)
  7. "Functional Mitral Regurgitation After Aortic Valve Replacement for Aortic Insufficiency" Journal of Cardiothoracic and Vascular Anesthesia (2018)