““Aortic dissection results from an intimal tear in the aortic wall. The primary morbidity and mortality results from extension of the tear. This extension is promoted by factors that increase the rate of change of aortic pressure (dp/dt), including elevation in BP, heart rate, and myocardial stroke volume. Blood pressure should be reduced promptly to near-normal levels. Aggressive control of BP with a vasodilator can trigger reflex tachycardia, leading to increased dp/dt.””