Aortic Insufficiency

(a leaky valve, pictured left)

Aortic Insufficiency: probably the most eponymous physical exam scenario....

• Pathophisiology: increased stroke volume results in an abrupt distention of peripheral arteries and elevation in blood pressure. This is followed by regurgitation through the valve back into the LV, causing a rapid fall in pressure with quick collapse for the arteries and a low diastolic pressure. This accounts for the majority of physical exam findings.


• Inspection of the Precordium: the apex may be displaced laterally or inferiorly.


• Palpation: displaced cardiac apex, with a hyperdynamic pulse. You may feel a thrill near the sternal notch.


• Heart Sounds: S1 may be soft secondary to a longer PR interval. An S3 will be heard in volume overloaded states.


• Murmur: typically a high-pitched early diastolic murmur, decrescendo in nature. It is best heard with a patient sitting up and leaning forward at end exhalation. Classic teaching suggests that if the murmur is loudest at the Right Sternal Boarder it represents aortic root disease, and if the murmur is loudest at the Left Sternal Border it represents aortic valve disease.


• Other Murmurs you may hear: A systolic murmur at the base that may mimic aortic stenosis - this is usually just a murmur from the high volume and flow of blood through the aortic valve during systole. Why so much during systole? Because a large fraction is regurgitationg back into the LV during during diastole. Also, an Austin-Flint Murmur may be heard. As Dr. Davis pointed out, this is a diastolic murmur heard at the apex of the heart that may mimic mitral stenosis.
  

Etiology of Aortic Insufficiency:

• Aortic Valvular Disease: Rheumatic heart disease, endocarditis, bicuspid aortic valve, myxomatous degeneration, rheumatoid arthritis, Marfan's, ankylosing spondylitis.
• Aortic Root Disease: HTN, dissecting aortic aneurysm, aortitis (from syphilis, ankylosing spondylitis, IBD, reactive arthritis), rare connective tissue diseases like Ehlers Danlose syndrome.
  

What's with all the eponyms? These are cool to see, but largely useless as they are not sensitive or specific, and are mostly related to the wide pulse pressure.

• DeMusset's sign: head bobbing with each heart beat.
• Becker's sign: visible pulsations in the retinal arterioles.
• Mueller's sign: systolic pulsations of the uvula.
• Quincke's sign: capillary pulsations in the finger tips.
• Rosenbach's sign: systolic pulsations in the liver.
• Gerhard's sign: systolic pulsations in the spleen. Usually you need an enlarged spleen to feel.
• Duroziez's sign: a systolic and diastolic bruit heard over the femoral artery when it is partially compressed. Note that when the distal part of your stethoscope is pressed down, the diastolic component will be accentuated.
• Pistol Shot sound: heard over the femoral artery.
• Hill's sign: when BP at the popliteal region is greater than the brachial BP by more than 20 mmHg.
• Water-hammer pulse aka Corrigan's sign: with a patient lying down, press down to obliterate the radial pulse. Then slowly raise their arm up and voila! The pulse becomes palpable again with the same amount of applied pressure.

So, is there any evidence for all this?

A little bit. Some smart folks in Toronto wrote a good JAMA article that you can read at this link. AI can be ruled out with the absence of an early diastolic murmur, and ruled in with the presence of an early diastolic murmur - the caveat? These murmurs were heard by cardiologists. Perhaps mere mortals like ourselves will hear it too.