With the Expert on: Valvular Aortic Stenosis

Q: Should aortic valve replacement be performed in an 80-year-old person with symptomatic severe aortic stenosis?

A: Case Presentation
An 80-year-old, previously functionally independent woman taking no medications has a 6-month history of substernal chest pressure precipitated by exertion and relieved by rest, an episode of syncope 2 months ago, and dyspnea at rest for the past 2 days. Physical examination in her physician’s office revealed a blood pressure of 110/80 mm Hg, a regular pulse at a rate of 96/minute, and a respiratory rate of 26/minute. Abnormal physical findings included a carotid pulse with a prolonged upstroke time, moist crepitant rales heard at both lung bases posteriorly, an absent A₂, audible third and fourth heart sounds heard at the apex, and a grade 2/6 systolic ejection murmur heard in the second right intercostal space that radiated down the left sternal border to the apex and upwards to the right carotid artery. The systolic ejection murmur was prolonged in duration and peaked in the second half of systole.

An electrocardiogram showed a regular sinus rhythm and left ventricular hypertrophy. A chest x-ray showed rounding of the left ventricular border and apex, poststenotic dilatation of the ascending aorta, and pulmonary vascular congestion. A Doppler echocardiogram showed severe valvular aortic stenosis with an aortic valve area of 0.6 cm². (A normal aortic valve opening is at least 2 cm. In mild aortic stenosis, the valve opens 1.50-2.0 square cm; in moderate aortic stenosis, the open valve area ranges from 0.8-1.49 square cm; and in severe aortic stenosis, the open aortic valve area is calculated to be less than 0.8 square cm.) A 2-dimensional echocardiogram showed a left ventricular ejection fraction of 45%.

Should This Patient Be Referred for Aortic Valve Replacement?
This elderly woman has the 3 classic manifestations seen with severe aortic stenosis: (1) angina pectoris, (2) syncope or near syncope, and (3) congestive heart failure, all of which are class I indications for aortic valve replacement (AVR), according to the American College of Cardiology (ACC)/American Heart Association (AHA) guidelines.¹ Her physical findings indicate severe valvular aortic stenosis confirmed by Doppler echocardiography. If the cardiac output becomes sufficiently decreased, the systolic ejection murmur may become decreased in intensity or absent once congestive heart failure develops. Her left ventricular ejection fraction of < 50% is another ACC/AHA class I indication for AVR. A study showed that at 13-month mean follow-up (range 2-24 months), 18 of 18 elderly patients (100%) with unoperated severe valvular aortic stenosis and a decreased left ventricular ejection fraction had died.²

AVR is the only definitive therapy in patients with symptomatic severe aortic stenosis. Medical therapy does not relieve the mechanical obstruction to left ventricular outflow and does not relieve symptoms or progression of the disorder.

A United Kingdom heart valve registry observed in 1100 patients aged ≥ 80 years (56% women) who underwent AVR that the 30-day mortality was 6.6%.³ The actuarial survival was 89% at 1 year, 79% at 3 years, 69% at 5 years, and 46% at 8 years.³ In 242 patients (mean age, 83 y) with aortic stenosis who had AVR, actuarial survival was 92% at 1 year and 66% at 5 years. Concomitant coronary artery bypass graft surgery did not affect late survival.⁴

Conclusion
In this previously functionally independent older woman with symptomatic severe aortic stenosis, AVR should be recommended to improve symptoms and prolong survival.

References
1. Bonow RO, Carabello BA, Chatterjee K, et al. ACC/AHA 2006 practice guidelines for the management of patients with valvular heart disease: Executive Summary. A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients With Valvular Heart Disease). Developed in collaboration with the Society of Cardiovascular Anesthesiologists. Endorsed by the Society for Cardiovascular Angiography and Interventions and the Society of Thoracic Surgeons. J Am Coll Cardiol 2006;48:598-675.
2. Aronow WS, Ahn C, Kronzon I, Nanna M. Prognosis of congestive heart failure in patients aged  62 years with unoperated severe valvular aortic stenosis. Am J Cardiol 1993;72:846-848.
3. Asimakopoulos G, Edwards M-B, Taylor KM. Aortic valve replacement in patients 80 years of age and older. Survival and cause of death based on 1100 cases: Collective results from the UK Heart Valve Registry. Circulation 1997;96:3403-3408.
4. Unic D, Leacche M, Paul S, et al. Early and late results of isolated and combined heart valve surgery in patients ≥ 80 years of age. Am J Cardiol 2005; 95:1500-1503.

Suggested Reading
Aronow WS, Weiss MB. Aortic valve disease in the elderly. In: Aronow WS, Fleg JL, eds. Cardiovascular Disease in the Elderly. 3rd ed. New York: Marcel Dekker, Inc; 2004:273-295.
Aronow WS, Kronzon I. Prevalence and severity of valvular aortic stenosis determined by Doppler echocardiography and its association with echocardiographic and electrocardiographic left ventricular hypertrophy and physical signs of aortic stenosis in elderly patients. Am J Cardiol 1991;67:776-777.