Hypertension Blog

Only 5% or fewer hypertensive patients have secondary hypertension. If a patient over age 50 suddenly develops hypertension, especially if it’s severe, suspect a secondary cause, such as a disease that increases cardiac output (CO) or peripheral vascular resistance. After the cause has been identified and treated, generally with surgery or drug therapy, the patient’s blood pressure should return to normal.

To identify the cause of secondary hypertension, a physician will order a basic workup that evaluates a patient’s cardiac system. Abnormalities in these systems commonly cause hypertension in young hypertensive patients, severely hypertensive patients, and hypertensive patients who don’t respond to standard antihypertensive therapy.

Cardiovascular Disorders

Coarctation of the aorta, a localized narrowing or constriction of the lumen of the aorta, is a vascular defect that commonly causes hypertension. Generally, the disorder is diagnosed in children.

Coarctation may occur anywhere along the aorta, but it most commonly occurs just beyond the origin of the left subclavian artery. When the condition is severe, the constriction of the lumen produces absent or markedly diminished femoral pulses as well as bruits heard throughout the posterior thorax.

Coarctation of the aorta can be detected by carefully timing the appearance of the patient’s femoral pulse with his radial or brachial pulse to determine if a substantial delay exists between pulses. If so, the patient’s blood pressure should be taken in both arms and his legs. The blood pressure of a patient with coarctation of the aorta will be elevated in the arms and reduced in the legs.

Surgical repair is usually required to correct coarctation of the aorta. Following surgical repair, only 5% to 10% of patients still have hypertension.

Subclavian artery stenosis also causes hypertension. If a patient has subclavian artery stenosis, his pulse in one arm will be absent or significantly diminished, and his blood pressure in that arm will be significantly lower than in his other arm.