Preoperative Evaluation and Questions: AS, AR, or both? If AS, how severe? Aortic valve opening: moderate AS = 0.7–0.9 cm2; critical AS = < 0.5 cm2 (normal = 2.6–3.5 cm2) Ao valve gradient: severe = > 50 mmHg Concurrent CAD? CHF? Esophageal stricture? surgery? injury? varices? (placement of TEE) AS is the most common valve […]