Which of the following is NOT typically used for blood pressure and heart rate control in aortic dissection?

• A. Hydralazine
• B. Nitroprusside
• C. Labetalol
• D. Nicardipine

Answer: (A)

In acute aortic dissection, the goal is to rapidly reduce shear stress on the aortic wall by lowering both blood pressure and heart rate. The preferred strategy is to blunt heart rate and contractility with a beta-blocker first, then use a vasodilator if needed to further reduce blood pressure. Hydralazine stands out because it primarily causes direct arteriolar dilation but often triggers reflex tachycardia and increased cardiac output, which can increase shear stress on the dissected aorta. This makes it less suitable for initial BP and HR control in dissection. The other drugs fit into the standard approach: labetalol provides both BP and HR reduction; nitroprusside lowers afterload but is typically paired with beta-blockade to prevent reflex tachycardia; nicardipine offers effective BP control with relatively manageable heart rate effects.