Aortic Regurgitation.
Left ventricular (LV) systolic function is an important determinant of long-term prognosis in patients with chronic aortic regurgitation (AR). Impaired LV systolic function identifies a group of patients who are at risk of developing postoperative congestive heart failure and death after aortic valve replacement (AVR). Hence, asymptomatic patients with definite evidence of impaired LV function should undergo operation without waiting for the development of symptoms or more severe LV dysfunction. Among asymptomatic patients with normal LV systolic function (normal ejection fraction), prognosis is excellent, and fewer than 5% per year require surgery because of symptom development or LV dysfunction. Patients likely to require surgery can be identified on the basis of age, severity of LV dilatation, and progressive increase in LV dimensions or decrease in resting ejection fraction during the course of serial follow-up studies. Afterload-reducing therapy in asymptomatic patients with severe AR and normal LV function has beneficial hemodynamic effects; chronic therapy may reduce the likelihood of symptoms or LV systolic dysfunction. Aortic valve replacement should be performed once significant symptoms develop. In the absence of important symptoms, the operation should also be performed in patients with AR who manifest consistent and reproducible evidence of either LV contractile dysfunction at rest or extreme LV dilatation. Noninvasive imaging should play a major role in evaluation. An important clinical decision--such as recommending AVR in the asymptomatic patient--should not be based on a single echocardiographic or radionuclide angiographic measurement. When these data consistently indicate impaired contractile function at rest or extreme LV dilatation on repeat measurement, however, operation is indicated in the asymptomatic patient. This strategy should reduce the likelihood of irreversible LV dysfunction in these patients and enhance long-term postoperative survival.
Bonow
RO
Division of Cardiology, Northwestern University Medical School, 250 East Superior Street, Suite 524, Chicago, IL 60611, USA.