Vessels UWorld 1 (All) Flashcards
Expression of COX enzymes
COX-1 is constitutively expressed, but COX-2 is only seen where inflammatory cells are activated. Thus COX-2 is an inducible enzyme.
V/Q studies show large perfusion defect, no ventilation defect.
Specific for pulmonary embolism
Colchicine
Binds to tubulin to inhibit microtubule formation, results in impaired neutrophil mitosis and decreased motility
Infliximab
Monoclonal antibody that irreversibly binds and inhibits TNF-a. Inhibits inflammatory response, used for autoimmune diseases (IBD, RA, psoriasis, ankylosing spondylitis)
First line tx of isolated systolic HTN
Thiazides and DHP CCBs
Doxazosin prazosin, terazosin: class, use, side effects
Alpha-1 blockers. Treat HTN and BPH. Cause first-dose effect, cause hypotension on initiation.
Eplerenone
Aldosterone antagonist
Aldosterone antagonist most common side effect
Gynecomastia
Homocysteine + methylcobalamin –>
Methionine
Temporal arteritis: therapy? Trying to prevent?
Steroids (prednisone) to prevent blindness
Embryologic origin of PDA
Pulmonary arteries and ductus arteriosus from the 6th aortic arch
What is used to close a PDA? Keep it open?
Close: indomethecin
Open: PGE2
What arteries are associated with embryonic aortic arches?
1) Maxillary 2) None 3) ICA 4) Arch of aorta, subclavian 5) none 6) Pulmonary arteries, ductus arteriosus
What cranial nerves are associated with the embryonic aortic arches?
1) Trigeminal (5) 2) Facial (7) 3) Glossopharyngeal (9) 4) Superior laryngeal of vagus (10) 5) none 6) Recurrent branch of laryngeal (10)
5-7-9-10-0-10
-sartan suffix
ARB = angiotensin receptor blocker
ARB mechanism, effects
Block effects of angiotensin II by blocking AT-1 receptors. Decrease aldosterone, reflex increase in renin, ATI, and ATII. No change on bradykinin.
ACE-I and ARB effects on bradykinin
Bradykinin is broken down by ACE, so ACE inhibitors increase levels of bradykinin, causing cough. ARBs do not have this effect.
How do metalloproteases affect atherosclerotic plaques?
involved in remodeling, instability and risk of rupture
Common side effects of statin therapy
Hepatotoxicity and myopathy. Myositis can lead to elevated serum creatinine kinase
Effect modification
occurs when the effect of a main exposure on an outcome is modified by another variale. E.g. likelihood that asbestos exposure will result in lung cancer impacted by smoking status
Transmural inflammation of arterial wall with fibrinoid necrosis
polyarteritis nodosa
Dopamine effects at low, med, high dose
Low = D1, increases GFR, vasodilation Med = D1+B1 = also increases HR, contractility, SBP High = D1+B1+a1 = generalized systemic vasoconstriction, decreased CO
Isolated systolic hypertension
After age 50, becomes common. Caused by decreased compliance in aorta
Causes of spontaneous intracranial hemorrhage in young adults
1) AVMs
2) Ruptured cerebral aneurysms
3) Drugs, such as cocaine
Adult-type coarctation of aorta
Aortic narrowing is post ductal (no need for PDA). Notching of ribs, hypertension of upper extremities, weak/delayed pulses in lower extremities.
What is adult coarctation of aorta associated with?
Other congenital cardiac abnormalities, Berry aneurysm. These patients die of HTN causes.
Lipoprotein lipase
hydrolyzes chylomicrons to triglycerides
Lipoprotein lipase deficiency
Results in increased concentrations of serum chylomicrons. Body cannot clear dietary lipid loads. Presents as hyperlipidemia and pancreatitis (abdominal pain)
How does heparin affect triglycerides?
Releases lipases from endothelium, increasing clearance of triglycerides from circulation
What does frothy foamy urine suggest?
Proteinuria or bile salts in urine
Churg-Strauss syndrome
Small vessel vasculitis, granulomatous necrotizing vasculitis with eosinophilia, MPO-ANCA and/or p-ANCA, increased IgE
Churg-Strauss presentation
Asthma, sinusitis, palpable purpura, peripheral neuropathy
May involve heart, GI, kidneys
Prevention of DVT in high risk pts (eg about to have hip surgery)
Heparine
Note: aspirin isn’t enough!
Saphenous vein graft - where do you get it?
Medial leg, inferolateral to the pubic tubercle
Phenoxybenzamine
Irreversible alpha blocker –> vasodilation. Major use is pheochromocytoma
Lymphangiosarcoma
Lymphatic malignancy associated with persistent lymphedema (e.g. several years post radical mastectomy)
Side effects of niacin, mediator
Mediated by prostaglandin. Skin flushing and warmth. Preventable with pre-treatment aspirin
“Red man syndrome”
Vancomycin side effect mediated by histamine
How does capsaicin reduce pain?
Decreases levels of substance P in PNS.
Energy for myocardial cellular function comes from: (3)
1) Fatty acid oxidation (60%, requires most oxygen)
2) Glucose oxidation (30%)
3) Glycolysis
Shifting this balance away from FA oxidation may help in angina, to decrease oxygen requirements
Fatty acid oxidation inhibitors
Inhibit fatty acid oxidation, which makes energy but requires a bunch of oxygen. Potential treatment for angina. Also may prevent buildup of toxic metabolites
ACE-I first dose concern
First-dose hypotension from reduced venous return to heart. Worse if pt is already hypovolemic/hyponatremic from diuretics.
Syphilis vascular compliations
Begins with vasa vasorum endarteritis and obliteration. Causes weakening of adventitia –> ascending aortic aneurysm –> aortic regurg.
Test for syphilis with FTA-ABS
Tx for BPH and hypertension
Alpha-1 blockers (doxazosin, prazosin, terazosin)
Tx for hypertension and heart failure
beta blockers
What drug increases serum CK?
Statins - myopathy
How do fibrates interact with statins?
Increase concentration of statins, and also causes myopathy on its own –> increased risk of mysitis
Fibrates plus bile resins - main side effect
gallstones
One-sided kidney atrophy in elderly pt with atherosclerosis
Renal artery stenosis
Volume of distribution
= amt of drug given / plasma concentration in body
Total body water? ECF? Plasma volume?
41 L, 14 L, 3L
Low Vd (3-5)
Drug stays in plasma. Bound to plasma proteins, high MW, or very polar
Medium Vd (around 15L)
Plasma plus interstitial volume (ECF). Drug is small and hydrophilic, so it can go to interstitial fluid.
Large Vd (around 40L)
Can cross membranes, reach intracellular compartments. Small MW and lipophilic.
Huge Vd (larger than total body water)
Avidly bound in tissues, accumulate in cells and keep low plasma concentrations.
Polyarteritis nodosa presentation, associated with
Fever, weight loss, malaise, headach. GI symptoms like abdominal pain, melena.
Hep B infection
What causes intermittent claudication?
Atherosclerosis of larger arteries
