51. The correct answer is D. A patient with aortic regurgitation, caused by insufficiency of the aortic valve, has a wide pulse pressure (the difference between systolic and diastolic pressure). In fact, during diastole, the systemic pressure precipitously drops as the blood flows from the aorta back into the left ventricle through the incompetent aortic valve. Systolic pressure remains relatively normal since it depends on the left ventricular ejection.
Aortic stenosis is associated with reduced systolic pressure and relatively preserved diastolic pressure, such as 95/80 mm Hg (choice B), since the left ventricle is unable to pump a normal amount of blood through a stenotic valvular orifice.
A blood pressure of 50/undetectable mm Hg (choice A) is characteristic of acute shock.
A blood pressure of 120/80 mm Hg (choice C) is considered within normal limits in healthy adults, whereas 160/95 mm Hg is definitely in the range of hypertension, although mild.
A blood pressure of 220/130 mm Hg (choice E) is typical of malignant hypertension, a severe condition that may lead to life-threatening complications if not promptly treated.