An 80-year-old male presents following a syncopal episode at home. Upon arrival at the ED, he is found to be afebrile, with a heart rate of 110 beats per minute, blood pressure 70/40 mm Hg, and respirations 26 per minute with an oxygen saturation of 78% on room air. Cardiovascular exam reveals a soft II/VI systolic ejection murmur at the right upper sternal border and rales throughout both lung fields. An echocardiogram detects critical aortic stenosis with a mean pressure gradient of 55 mm Hg across the aortic valve and a calculated aortic valve area of 0.5 cm2. Which of the following is appropriate therapy at this time?
A. Nitroprusside intravenously and intraaortic balloon counterpulsation
B. Dobutamine infusion
C. Emergent aortic valve replacement after coronary angiograph
D. Emergent aortic valve balloon valvotomy
E. All of the above are reasonable
F. A and C are reasonable