In the presence of AS, the obstruction of left
ventricular outflow results in increased peak systolic
wall stress. This chronic pressure overload directly
stimulates parallel replication of sarcomeres in
the left ventricle, with consequent development of
concentric hypertrophy. Figure 1 shows a typical
pressure-volume loop for a patient with AS. The
Figure 1: Pressure-volume loop in aortic stenosis.
peak pressure generated by the left ventricle
during systole is much higher because of the
high transvalvular pressure gradient. Concentric
hypertrophy decreases systolic myocardial wall
stress from the increasing afterload. However, it also
leads to diastolic dysfunction with an increase in
left ventricular end-diastolic pressure (LVEDP) and
subendocardial ischemia. Eventually, the ejection
fraction is somewhat decreased, indicating reduced
Valvular Heart Disease in the Patient
Undergoing Noncardiac Surgery
Nancy A. Nussmeier, MD
Chair, Department of Anesthesiology
SUNY Upstate Medical University, Syracuse, NY55
IARS 2010 REVIEW COURSE LECTURES