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Chapter 1 1. b. Vascular smooth muscle cells (not endothelial cells) migrate into the intima during atherosclerosis initiation. Endothelin is primarily a vasoconstrictor via the endothelin A receptor on vascular smooth muscle. Endothelin can act on endothelin B receptors on endothelial cells to increase nitric oxide (a potent vasodilator), but the net effect of endothelin on arteries is dominated by the vasoconstrictor effect on endothelin A receptors. The smaller muscular arteries (rather than elastic arteries) regulate resistance. The adventitia contains connective tissue, but the media contains abundant smooth muscle and connective tissue. 2. e. HDL is considered the main transport lipoprotein for reverse cholesterol transport, which removes cholesterol from peripheral tissues. 3. c. Nitric oxide tends to prevent activation of NF-κB. The selectins are most responsible for monocyte rolling, whereas the CAMs are most responsible for monocyte arrest and recruitment into the artery wall. MCP-1 enhances (not blocks) monocyte recruitment. 4. e. All are found in advanced plaques. 5. b and e. Monocytes and leukocytes are more characteristic of atheroma than are neutrophils. Therapies that lower LDL levels usually do not decrease plaque size. Most human studies (intravascular ultrasonographic and angiographic) suggest intensive lipid lowering is associated with small changes in plaque size (generally less than 5%) compared with the large decrease in the risk of clinical events. Calcification is an active (not passive) process that in some cases mimics construction and destruction processes seen in bone. 6. b. Compensatory enlargement refers to the enlargement of the whole artery to accommodate the athero© 2007 Society for Vascular Medicine and Biology
sclerotic plaque to preserve the lumen size. Over time this process is thought to be overwhelmed and the lumen decreases in size. Negative remodeling refers to a decrease in size of the whole artery segment; this tends to contribute to lumen narrowing and the development of stenoses. Metalloproteases are more often found in positively remodeled arterial segments and are thought to contribute to the growth of the artery.
Chapter 2 1. d 2. b 3. c 4. b 5. b
Chapter 3 1. c 2. a 3. d 4. d 5. a 6. d 7. f 8. a
Chapter 4 1. c. The calf pump failure syndrome is caused by either retrograde flow through incompetent perforator veins during calf muscle contraction or ineffective muscle contraction, both of which result in secondary varicose veins. 313
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2. c. May-Thurner syndrome is caused by compression of the left iliac vein by the right iliac artery as the vein crosses over to the left leg. The term “May-Thurner syndrome” is only used when significant venous obstruction is produced by the overlying artery. During pregnancy, an otherwise normal woman may have symptoms of this condition, due to increased intra-abdominal pressure. 3. c. The Trendelenburg test is a simple bedside test that can help distinguish primary from secondary varicose veins and should be performed before consideration of sclerotherapy. She had no symptoms or history of DVT, and duplex ultrasonography would be the preferred diagnostic test to exclude DVT rather than venography. The veins will decompress with elevation, but neither bed rest nor analgesics will resolve her condition in the long term. 4. b. Reducing edema is the most important element of CVI treatment and decreases cutaneous complications. Diuretics only help edema minimally. Small ulcers should be treated first with aggressive medical therapy before consideration of skin grafting. In the SEPS procedure, ligation of perforator veins is performed under endoscopic guidance. 5. c. Filariasis is the most common cause of lymphedema worldwide and is especially prominent in Africa, India, and South America. Lymphedema sometimes secondarily complicates CVI. Milroy disease is a form of familial primary lymphedema. 6. d. This patient has lymphedema praecox, which typically presents during puberty. The patient has swelling that extends into the feet and toes with cutaneous fungal infection, which are characteristics of lymphedema. Stemmer sign is positive if the skin at the base of the toes cannot be pinched. Swelling from lymphedema usually progresses slowly up the leg over time.
Chapter 5 1. e 2. c 3. a 4. d 5. d 6. b
Chapter 6 1. e 2. c 3. c 4. f 314
5. e 6. d
Chapter 7 1. c. Both PW and CW Doppler instruments can detect forward and reverse flow, but CW Doppler instruments are less costly and simpler to use. The penetration of ultrasound in tissue is primarily dependent on transmitting frequency (with lower frequencies penetrating to deeper depths) and is the same for PW and CW Doppler. Only PW Doppler can distinguish between flow at different sites or depths in tissue. 2. a. Compressibility (or stiffness) should not affect pneumatic cuff pressure measurements in normal tibial and brachial arteries. However, if calcification or atherosclerotic occlusive disease is present in the tibial arteries, they may be less compressible, which leads to erroneously high cuff pressure measurements. The mean arterial pressure decreases as the pulse moves distally, whereas the systolic pressure increases and the diastolic pressure decreases (so the pulse pressure widens). Because the brachial artery site of pressure measurement is closer to the heart, this augmentation or increase in systolic pressure makes the normal ankle pressure greater than the arm pressure and the ABI greater than 1.0. Cuff artifacts should not be significant at the brachial and ankle sites. 3. b. The digital arteries are not affected by medial calcification, even if the tibial arteries are heavily calcified. Toe-brachial indices are in the range of 0.80 to 0.90 in normal persons. It is often difficult to obtain Doppler flow signals from the toes, and PPG is easier to use for this purpose. Although patients with diabetes mellitus are especially prone to medial calcification in the tibial arteries, the digital arteries are not involved, so toe pressure measurements are not different in diabetic and non-diabetic patients. 4. d. The normal segmental plethysmographic waveform is characterized by a rapid steep upstroke, a sharp systolic peak, and a more prolonged downslope that bows toward the baseline. Changes in amplitude alone generally have little diagnostic significance. A prominent dicrotic wave is normally seen on the downslope of the waveform and represents the reverse-flow phase of the arterial flow pulse. Significant arterial occlusive disease proximal to the recording cuff is excluded by the presence of a dicrotic wave. 5. c. The maximum change in ankle pressure after treadmill exercise occurs immediately after walking, so it is important to measure pressures as quickly as possible. A slight increase in ankle pressure after treadmill exercise is often seen in normal persons. Patients with signifi-
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cant arterial occlusive disease typically have symptoms within 5 minutes of walking at 2 mph up a 12% grade, and more prolonged exercise times are rarely necessary. Some mild-to-moderate arterial lesions are not hemodynamically significant at resting flow rates, but they become flow limiting when flow rates are increased by exercise.
3. d 4. d 5. c 6. b 7. a
Chapter 11 Chapter 8 1. b 2. e 3. d 4. a 5. d
1. e 2. d 3. d 4. e 5. d 6. e 7. b
Chapter 9
Chapter 12
1. c. This patient has intermediate risk factors and is scheduled to undergo a high-risk vascular operation. β-Blockers decrease the risk of adverse preoperative cardiovascular events; this medical management in this situation would result in an outcome similar to coronary revascularization before vascular surgery. 2. a. This patient has an impending rupture of an abdominal aortic aneurysm and requires urgent surgery. Performance of any cardiac tests would delay the operation. 3. d. This patient has a symptomatic carotid stenosis. Carotid endarterectomy, an intermediate-risk procedure, should be performed. She has excellent functional capacity and minimal risk factors. She can proceed directly to surgery with perioperative administration of β-blockers and aspirin because she is at low risk for an adverse cardiovascular event. 4. a. This patient likely has three-vessel coronary artery disease, left ventricular dysfunction, and angina. The popliteal artery aneurysm repair is elective. Regardless of the popliteal artery aneurysm, he should be referred for cardiac catheterization as a prelude to a coronary revascularization procedure. 5. a. According to the ACC/AHA practice guidelines, the presence of symptomatic aortic valvular stenosis, even in the absence of a critical stenosis (