[Asymptomatic aortic stenosis. When to operate, when to follow?]

While there is generell agreement that patients with aortic stenosis (AS) who have already developed symptoms, such as exertional dyspnea, angina or dizziness and syncope, require urgent surgery because of their otherwise very poor outcome, the management of asymptomatic severe AS remains controversial. Although prevention of sudden death, prevention of irreversible myocardial damage, lower operative risk and a possible short duration of the asymptomatic phase of the disease have been proposed as arguments for early elective surgery, currently available data do not support that the risk of surgery and prosthesis-related long-term complications can generally be outweighed by a potential benefit. Thus, surgery cannot be recommended for all asymptomatic patients. Since patients often do not report their symptoms immediately and waiting lists for surgery exist in some countries, risk stratification with selection of those patients who are likely to develop symptoms and require surgery within a short time period seems to be the ideal approach. The most important predictors of outcome are the degree of valvular calcification, the hemodynamic progression rate, the development of symptoms during exercise testing, and plasma levels of cardiac neurohomones.