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Figure 8 Dobutamine stress echocardiography was requested in this 52-year-old man with a history of radiation therapy with heart failure symptoms, left ventricular dysfunction, and a calcified aortic valve. With dobutamine, ejection fraction (EF) and stroke volume (SV) increased, indicating contractile reserve. Outflow tract peak velocity increased from 0.9 to 1.0 cm/s (left ventricular outflow tract [LVOT] diameter 2.2 cm), so calculated aortic valve area was unchanged at 1.0 cm² at rest and at peak dose dobutamine consistent with stiff inflexible leaflets. AS-Jet = aortic jet.