A 76-year-old man presents with exertional syncope and angina. Examination reveals a slow-rising carotid pulse and a harsh systolic murmur radiating to the neck. Echocardiography shows AVA 0.6 cm², mean gradient 52 mmHg, EF 55%. What is the most appropriate management?
A
Aggressive medical therapy with beta blockers
B
Observation with serial echocardiography
C
Urgent aortic valve replacement
D
Balloon aortic valvuloplasty as definitive therapy