Aortic Stenosis can be diagnosed after detailed patient history, physical examination and echocardiography performed by specialist cardiac sonographers.
A chest x-ray showing cardiomegaly may be indicative of left ventricular (LV) systolic failure. Other non-specific findings on a chest x-ray may be:
• calcification of the aortic valve;
• pulmonary congestion; and
• post-stenotic dilation of the aorta.
A patient with aortic stenosis may also have a systolic, “crescendo-decrescendo’ murmur that may be heard at the right sternal border, in the second intercostal space. This may radiate into the carotid arteries bilaterally, which is usually heard best when sitting the patient upright. The loudness of the murmur does not equate to the severity of the disease.
A 12 lead ECG at rest or during the examination may reveal evidence of Left Ventricular Hypertrophy (typically tall R waves in V5-6, and deep S wave in V1-2) in patients with Aortic Stenosis, although severe AS without significant LV Hypertrophy is a well-recognised entity.1
Image 1: Example of a 12 lead ECG showing left ventricular hypertrophy2
The echocardiogram confirms the diagnosis and the severity of aortic stenosis. Two-dimensional echocardiography can demonstrate a thickened aortic valve, reduced leaflet mobility, and concentric left ventricular hypertrophy. Doppler can be used to quantify the severity of aortic stenosis by measuring the pressure gradient across the aortic valve and by calculating the aortic valve area (AVA). The velocity of blood flow across the aortic valve, as determined by continuous-wave doppler, is used to calculate the transaortic pressure gradient.