Hypertension Case 3

Hypertension Case 3

A 34-year-old man undergoing a routine physical examination is found to have a blood pressure of 165/105 mm Hg. The measurement is repeated 40 minutes later, and is 162/103 mm Hg. The physician asks the patient to return the next week and the week following, and each
time repeats the evaluation yielding the following results: 170/102, 168/107, 175/108, 167/102 mm Hg.

Q 1
This patient's blood pressure should be classified as which of the following?
/ A. Optimal
/ B. Normal
/ C. High-normal
/ D. Stage 1 (mild) hypertension
/ E. Stage 2 (moderate) hypertension
/ F. Stage 3 (severe) hypertension

Q 2
How many Americans over the age of 5 have high blood pressure?
/ A. 50 thousand
/ B. 500 thousand
/ C. 5 million
/ D. 50 million
/ E. 150 million

Q 3
What percentage of these patients have essential hypertension?
/ A. Less than 5%
/ B. 10-15%
/ C. 40-50%
/ D. 70-80%
/ E. 90-95%


Q4
Years of untreated hypertension would be most likely to cause which of the following cardiac changes?
/ A. Large vegetations on cardiac valves
/ B. Left ventricular hypertrophy
/ C. Patent foramen ovale
/ D. Pericarditis
/ E. Pulmonary stenosis


Q 5
Patients with hypertension would be most likely to have which of the following findings on renal biopsy?
/ A. Crescent formation
/ B. Hyaline arteriosclerosis
/ C. KimmelstieI-Wilson nodules
/ D. Papillary necrosis
/ E. Subepithelial electron-dense humps


Q 6
Examination of the eye of a patient with long-standing hypertension shows "cotton wool spots." These are due to which of the following?
/ A. Crystal deposition in the lens
/ B. Hemorrhage in the lens
/ C. Hemorrhage in the retina
/ D. Ischemia of the lens
/ E. Ischemia of the retina


Q 7
The medical therapy of hypertension offers innumerable choices but, in this case, the decision was made to treat the patient with an ACE inhibitor. Which of the following drugs belongs to this class?
/ A. Atenolol
/ B. Diltiazem
/ C. Enalapril
/ D. Hydrochlorothiazide
/ E. Losartan


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Hypertension Case 3 Answers

A1
The correct answer is E. This patient has moderate hypertension. It is important not to try to diagnose hypertension based on the finding of a single abnormal blood pressure result, particularly since many patients feel uncomfortable during medical examination and may have transient blood pressure elevations. One protocol commonly used is to take two or more blood pressure readings on the first examination, and then have the patient come back twice, taking two or more blood pressure readings on the subsequent examinations. The average systolic and diastolic pressures from the visits after the first one are then used to stage the degree of hypertension:
Optimal blood pressure (choice A): systolic less than 120 and diastolic less than 80.
Normal blood pressure (choice B): systolic less than 130 and diastolic less than 85.
High normal (choice C): systolic 130-139 or diastolic 85-89.
Stage 1 (mild) hypertension (choice D): systolic 140-159 or diastolic 90-99.
Stage 2 (moderate) hypertension (choice E): systolic 160-179 or diastolic 100-109.
Stage 3 (severe) hypertension (choice F): systolic more than 180 or diastolic more than 110.
If the systolic and diastolic values fall into different stages, the patient is considered to have the higher stage.


A2
The correct answer is D. 50 million Americans aged 6 and older have high blood pressure. This corresponds to one in five Americans, or one in four adults. The incidence of hypertension is highest among African Americans, but other races known to have an increased incidence of hypertension include Mexican Americans, American Indians, native Hawaiians, and some Asian Americans. It is suspected that dietary salt intake, obesity, and genetic differences all play a role in these racial differences. About 30% of people with high blood pressure know that they have it, and only about 24% of patients with high blood pressure have it controlled to pressures of less than 140/90 mm Hg (considered optimal). The remainder are either untreated or inadequately treated. The medical implications of this are obvious.


A3
The correct answer is E. Major risk factors for essential hypertension (cause is unknown) include diabetes mellitus, family history of hypertension or cardiovascular disease, high cholesterol, obesity, smoking, high salt diet, alcohol use, and stress. Additionally, older individuals, African Americans, and males are at increased risk. Nonetheless, in 90-95% of individuals with hypertension, the cause is never identified, and the individual is considered to have essential or primary hypertension. This means that, in practice, although physicians should always keep in mind the possibility of other, specific causes of hypertension (e.g., renal artery stenosis, pheochromocytoma, other endocrine disease, coarctation of the aorta), these other conditions will not usually be found.


A4
The correct answer is B. High blood pressure directly killed 43,000 Americans, and contributed to the deaths of 227,000 additional Americans. Direct deaths are due to processes like stroke, ruptured berry aneurysm, and ruptured aortic aneurysm. Many of the indirect deaths are related to the vascular damage that high blood pressure causes. High blood pressure is a major contributor to the formation of atherosclerotic plaques, and has a much more than additive effect when added to other atherosclerotic risk factors, such as obesity and diabetes mellitus. In addition to the large vessel damage, small arterioles can also be damaged, which are most apparent in the kidney and eye. The cardiac complication of hypertension that you are most likely to be asked about on a USMLE examination is left ventricular hypertrophy. This occurs in 15 to 20% of patients with hypertension, apparently as a result of the response to the various stimuli that accompany blood pressure elevation. The left ventricular hypertrophy may be either concentric (involving the entire chamber) or eccentric (involving localized sites, often including the septum). Concentric hypertrophy is thought to be an indicator of poor prognosis, and may lead to the development of first diastolic, and then later systolic dysfunction of the cardiac muscle. In addition to the left ventricular hypertrophy, other changes have been associated with hypertension, including left atrial abnormalities, aortic insufficiency, heart failure, myocardial ischemia, and cardiac arrhythmias.
Large vegetations on cardiac valves (choice A) suggests endocarditis.
Patent foramen ovale (choice C) is a congenital lesion.
Pericarditis (choice D) can be due to infection, uremia, and inflammatory disorders.
Pulmonary stenosis (choice E) is usually congenital in origin.

A5
The correct answer is B. Hyaline arteriosclerosis is the characteristic lesion seen on biopsy in patients with essential hypertension. This lesion is associated with thickening of the wall (due to deposition of serum components) and narrowing of the lumen of the afferent arterioles that enter the glomerulus. The lesion may be associated with a secondary obsolescence of the glomeruli.
Crescent formation (choice A) is seen in rapidly progressive glomerulonephritis.
Kimmelstiel-Wilson nodules (choice C) are a feature of diabetic glomeruli.
Papillary necrosis (choice D) can be seen in analgesic abuse, diabetes mellitus, pyelonephritis, sickle cell disease, and urinary tract obstruction.
Subepithelial electron-dense humps (choice E) are a feature of post-infection glomerulonephritis.


A6
The correct answer is E. Early changes seen on ocular examination of hypertensive individuals can include narrowing of arteries and arteriovenous junction changes. Late changes seen can include deposits of lipids in the eye, cotton wool spots, bleeding in the eye (which may cause retinal detachment), venous occlusion (which may cause transient or permanent loss of vision), and new vessel growth. The cotton wool spots are actually small areas of transient retinal ischemia, and usually resolve within days. Cotton wool spots are also commonly seen in diabetics and HIV patients.
Crystal deposition in the lens (choice A) produces a cataract.
Choices B and D are distracters.
Hemorrhage in the retina (choice C) can produce "flame lesions" and retinal detachment.


A7
The correct answer is C. Life style modifications (decreased salt intake, weight reduction, more exercise) offer some help in reducing blood pressure, but most patients with high blood pressure eventually require medications. We now have an enormous array of medications that can be used in the treatment of hypertension. This is good for the patients, because it means that it is almost always possible to find (with enough time) some effective medication that a particular patient can tolerate. In actual practice, most physicians develop a few favorite drugs with which they often start patients, and then modify the medications based on blood pressure response, patient complaints, and coexisting diseases. Classes of hypertensive medications include diuretics, beta-blockers, long-acting Ca++ blockers, ACE-inhibitors, angiotensin II receptor blockers, and alpha-adrenergic blockers. Examples of ACE-inhibitors include captopril, benazepril, enalapril, fosinopril, lisinopril, moexipril, quinapril, ramipril, and trandolapril. These agents act by disrupting the renin-angiotensin system by blocking angiotensin converting enzyme.
Atenolol (choice A) is a beta-1 blocker and has direct effects on blood vessels and cardiac function.
Diltiazem (choice B) is a calcium channel blocker, which partially inhibits smooth and cardiac muscle function.
Hydrochlorothiazide (choice D) is a diuretic and acts by decreasing the volume of blood in the vascular space.
Losartan (choice E) is an angiotensin II receptor blocker, and disrupts the renin-angiotensin system by blocking the actions of angiotensin II. Some patients who have trouble tolerating ACE inhibitors do well with angiotensin II receptor blockers.