Aortic Regurgitation Case Discussion

A 56-year-old man is seen because of progressive fatigue, dyspnea on exertion, orthopnea, and paroxysmal nocturnal dyspnea. On physical examination his blood pressure is 160/60 mm Hg. There is no jugular venous distention, but systolic pulsations of the uvula are noted, as is quick collapse of the arterial pulses, which is seen in the nail beds with gentle pressure. The lungs are clear to percussion and auscultation. There is a diffuse and hyperdynamic apex beat that is displaced laterally and inferiorly, soft first and second heart sounds, a loud third heart sound, and a grade 3/6, high-pitched, nearly holodiastolic murmur heard best at the upper left sternal border along with a grade 3/6 systolic ejection type murmur at the upper left sternal border radiating to the carotids. A late diastolic rumble is heard at the apex as well as a third heart sound.

What is the most likely valvular lesion in this patient?
What is the likely underlying cause of aortic regurgitation in this patient?
What is the appropriate medical therapy for the patient with aortic regurgitation?
When should aortic valve replacement be considered in a patient with chronic aortic regurgitation?
What is the surgical therapy for severe aortic regurgitation?

Case Discussion
What is the most likely valvular lesion in this patient?
This patient has chronic severe aortic regurgitation. There are many physical signs to look for in the setting of aortic regurgitation, some of which are seen in this patient. These include de Musset's sign (the head bobs with each heartbeat), Corrigan's sign or waterhammer pulses, Traube's sign (booming systolic and diastolic sounds heard over the femoral arteries), Muller's sign (systolic pulsation of the uvula), Quincke's sign (capillary pulsations seen in the nail beds), and others. All of these are signs of large stroke volume and wide pulse pressure characteristic of chronic aortic regurgitation. The loud 3/6 diastolic murmur heard at the upper left sternal border is the murmur of aortic insufficiency and the systolic murmur is due to turbulent flow across the aortic valve because of the large amount of blood crossing the aortic valve. The mid-to-late diastolic rumble, namely the Austin Flint murmur, is created by rapid retrograde flow from the aorta striking the anterior mitral leaflet. Another explanation for this murmur is that the large volume of regurgitant flow partially closes the mitral valve, creating a late diastolic mitral valve gradient.
What is the likely underlying cause of aortic regurgitation in this patient?
In this age-group, the most likely cause of aortic regurgitation is a bicuspid aortic valve. Causes of aortic regurgitation can be broken down into two general categories—valvular disease and aortic root disease. Rheumatic heart disease, infective endocarditis, trauma, bicuspid valve, other congenital valvular defects (e.g., a fenestrated valve), systemic lupus erythematosus, rheumatoid arthritis, ankylosing spondylitis, and Whipple's disease may cause primary valvular disease. Cystic medial necrosis of the aorta (isolated or associated with Marfan's syndrome or Ehlers-Danlos syndrome), atherosclerosis, hypertension, syphilitic aortitis, and others may cause aortic root dilatation and deformity of the aortic valve, leading to inability of the valve to coapt. A dissection of the aorta may also cause aortic regurgitation by dissecting into the valve itself.
What is the appropriate medical therapy for the patient with aortic regurgitation?
The use of vasodilators to delay the progression of aortic regurgitation and left ventricular dysfunction in asymptomatic patients is controversial and definite evidence of a benefit has not been demonstrated. In patients with symptoms of HF due to aortic regurgitation, vasodilators may provide symptomatic benefit but should not delay referral for aortic valve replacement.

When should aortic valve replacement be considered in a patient with chronic aortic regurgitation?
Aortic valve surgery should be considered if the patient has symptoms of HF. In the asymptomatic patient, aortic valve replacement is recommended if the EF falls below normal or if the end-systolic dimension of the left ventricle is larger than 55 mm.
What is the surgical therapy for severe aortic regurgitation?
Aortic valve replacement with a prosthetic valve is the only surgical option in most patients.