A 40 year-old man presents to his family doctor after getting his blood pressure checked at a local health fair. His blood pressure was measured as 180/100 mm Hg. He has no symptoms or complaints. His blood pressure today was 178/98 mm Hg. Based on these two readings, he is diagnosed with stage 2 hypertension. He has a significant family history of essential hypertension. His examination is normal other than an enlarged and laterally displaced point of maximal impulse on cardiac examination. His body mass index is normal. His physician orders a urinalysis, complete blood count (CBC), fasting lipid profile, and a chemistry panel that includes serum glucose, potassium, creatinine, and calcium. An ECG shows left ventricular hypertrophy (Figure 49-1). He is counseled regarding lifestyle changes, started on two medications, and asked to follow-up within a couple of weeks.
EKG showing left ventricular hypertrophy in this 58-year-old man with current blood pressure of 178/98. Note how S V1 + R V5 > 35 mm. Also his ECG shows left axis deviation and nonspecific ST changes in the high lateral leads (I and aVL). (Reproduced with permission from Gary Ferenchick, MD.)
Hypertension (HTN) is a major risk factor for both myocardial infarction and stroke. Primary HTN constitutes 90% of HTN cases. Initial treatment includes lifestyle modifications and medications. Most patients require at least two medications to achieve control. Patients who cannot be controlled on three medications should undergo a work-up for secondary causes.
29% of U.S. adults older than age 18 years have HTN.1
Blood pressure is controlled in approximately 50% of adults with HTN.1
Blood pressure control is lowest among those without health insurance (29%), Mexican Americans (37%), and younger adults ages 18 to 39 years (31%).1,2
In the United States, HTN contributes to 1 of every 7 deaths and to half of the cardiovascular disease-related deaths.2
Cost of HTN to the U.S. healthcare system is estimated to be $93.5 billion per year.2
ETIOLOGY AND PATHOPHYSIOLOGY
Primary HTN (>90% of patients)—A specific cause is unknown, but environmental factors (salt intake, excess alcohol intake, obesity) and genetics both play a role.
Secondary HTN (5% to 10% of patients)—Causes include medications, kidney disease, renal artery stenosis (Figure 47-2), thyroid disease, hyperaldosteronism, and sleep apnea. Rare causes include coarctation of the aorta, Cushing syndrome and pheochromocytoma.
Angiogram revealing bilateral renal artery stenosis (arrows), one of the more common causes of secondary hypertension, most often a result of atherosclerotic disease in older patients. (Reproduced with permission from Fuster V, Walsh R, Harrington RA: Hurst the Heart, 13th ed. New York, NY: McGraw-Hill Education; 2011...