Predicting Outcome in Patients With Asymptomatic Aortic Stenosis

Abstract

A lthough the annual risk of cardiovascular mortality has been well described for individuals with symptomatic aortic stenosis, the morbidity and mortality for those with asymptomatic severe aortic stenosis is not as well known. Currently the American Heart Association/American College of Cardiology recommends a "watchful waiting" strategy for those with asymptomatic aortic stenosis. 1 This involves clinical examinations every 6 to 12 months and annual echocardiograms; however, it is unclear what to do with these data in the patient who remains asymptomatic. The asymptomatic patient is generally not referred for aortic valve replacement surgery until the development of symptoms (unless concurrent coronary artery bypass grafting is required or if systolic dysfunction develops). Article see p 69Approximately 30% of asymptomatic patients will develop symptoms (angina, heart failure, syncope) within 2 years of diagnosis. 2,3 For those patients who do not develop symptoms, the risk of sudden cardiac death is less than 1% per year, assuming that patients are well monitored for the development of symptoms. 2,3 Although angina and syncope are relatively easy symptoms to elicit, manifestations of heart failure may be subtle. This is particularly true because many of these patients are elderly and attribute reduced exercise capacity to be part of the normal aging process or "slowing down." Vigilance and careful attention to a patient's history are important components of the regular evaluation of patients with aortic stenosis. However, even careful attention to the history may not predict sudden death in patients with severe aortic stenosis. The reluctance to perform surgery earlier than necessary is driven by the morbidity of cardiac surgery and a mortality rate for aortic valve surgery of approximately 3% to 5%, even in patients younger than 70 years. 4 Thus for truly asymptomatic patients, the risk of potential complications like sudden cardiac death and irreversible myocardial dysfunction must be weighed against the risk of surgery. Given the possibility of these outcomes before the development of overt symptoms, investigators have sought to find a reliable way in which to risk stratify patients with asymptomatic aortic stenosis into those who will derive benefit from surgery before symptom development and those who will not. A comprehensive objective approach that could facilitate decision making in such patients has long been sought but has been elusive.In this issue of Circulation, Monin et al 5 describe a scoring system for patients with asymptomatic severe aortic stenosis based on the premise that both the state of the valve and the ventricle must be considered when assessing risk in asymptomatic patients. The risk of valve-specific factors such as aortic valve area, aortic valve calcification, transvalvular gradients, and peak aortic velocity have been well described, but the prognostic value of each or a combination of anatomic and functional valve information has not been consistently predictive of outcome. 6 ...

Prognostic Value of Circulating MicroRNA-210 Levels in Patients with Moderate to Severe Aortic Stenosis

“…However, as the majority of patients with AS are elderly, a large proportion of the patients have a sedentary life style, causing a delay in the recognition of symptoms [1]. Hence, irreversible myocardial damage may occur before the patients experience symptoms, and additional means to identify high-risk patients are needed [2].…”

Association of Myocardial Deformation With Outcome in Asymptomatic Aortic Stenosis With Normal Ejection Fraction

“…8 Given the chances of adverse outcomes before the development of overt symptoms, investigators have sought to find a reliable approach in which to risk-stratify patients with asymptomatic AS into those who will benefit from surgery before symptom development. 9 …”

When to use stress echocardiography in the evaluation of patients with valvular heart disease

“…(90,91) The risk of sudden death in asymptomatic patients with severe aortic stenosis is <1% per year (92,93) and some asymptomatic patients with severe aortic stenosis may develop irreversible left ventricular dysfunction, although there is no reliable data to suggest that irreversible left ventricular dysfunction develops as a result of severe aortic stenosis in the absence of symptoms. (8) The risk of adverse outcomes with aortic valve replacement on the other hand is about 3-5% and therefore aortic valve replacement is not recommended routinely for asymptomatic patients with severe aortic stenosis.…”