UWorld Test 5/20/2014 - Cardio and general Flashcards
Major determinant of whether or not a coronary artery plaque will cause ischemic injury is?
Rate at which it occludes the artery. Slow developing occlusion allows for the formation for collaterals
thin fibrous cap, rich lipid core, active inflammation increases or decreases plaque stability?
Decreases - more prone to rupture
Character of pericarditis chest pain? Exacerbated by? Relieved by?
Sharp, friction rub. Exacerbated by swallowing. Relieved by sitting up/leaning forward
What are the types of pericarditis that can happen after MI? When do they happen?
Early onset pericarditis happens in 10-20% of patients, happens 2-4 days after event. Inflammatory reaction to necrotic myocardium that happens to adjacent visceral and parietal percardium. Dresslers syndrome happens 1 week to several weeks after event. Thought to be autoimmune polyserositis
What is myocardial hibernation?
Persistent or repetitive low flow state that can lead to reversible loss of contractile function. It can be reversed by reperfusion. Mycoardial stunning is a less severe form of this. Repetitive stunning can lead to hibernation.
What is ischemic preconditioning?
Development of resistance to infarction by myoctes previously exposed to sub lethal ischemia.
How does aortic stenosis affect the LV - aorta pressure gradient in “the graph”
Normally, aorta pressure and lv pressure are on top of each other (same) during systole but in aortic stenosis, there is a gradient such that the LV pressure is greater than the aortic pressure.
Holosystolic murmur that increases In intensity during inspriation is?
Tricuspid regurgitation. Upon inspiration, there is greater venous return to the RA/RV, more volume => increases intensity of murmur. On the left side, there is increases pulmonary vein capacity, and less venous return to the left heart so there is no change in murmur sound.
Why is the pathophysiology behind S3?
Occurs in early diastole during rapid ventricular filling phase. A/w increased filling pressures. For example, in mitral regurg there is increased volume due to the regurgitant volume/increased rate of filling. Also heard in LV systolic function failure. Heard when blood rushes into partially filled ventricle. Also when filling stifff ventricle. Also more common in dilated ventricles (more normal in pregnant women and children)
What is the most reliable auscultuary finding indicating severity of mitral regurgitation
S3. Intensity of holosystolic murmur is not indicative since larger regurgitant volumes are also a/w larger orifices and can present with softer murmurs.
Bell of stethoscope is best sutied for? Diaphragm is best for?
Bell - low frquency sounds like S3. Diaphragm - high frequency sounds.
S4 sound is due to?
Low frequency sound due to decreased left ventricular compliance. A/w LVH and restrictive cardiomyopathies.
What is the most common cardivascular syndrome associatd with Lupus
Pericarditis. Libman sacks endocarditis is another cardio manifestation in lupus patients.
Golden yellow or brownish cytoplasmic granules may be? What test can be used to distinguish the two possibilities
Lipofuscin or hemosidern. Prussian blue stain = colorless potassium ferrocyanide is converted by iron to blue black ferrocyanide.
What is the most effective treatment for hypertriglyceridemia
Niacin and Fibrates
Stimulation of vagal nerve branches that supply the lung would result in?
Parasympathetic, i.e. muscarinic/Ach activity => Bronchoconstriction, increased bronchial secretions. Therefore increased work of breathing.
What is the MOA for rifampin? What is the mechanism of resistance for Ripampin?
Inhibits bacterial DNA dependent RNA polymerase => inhibits transcription. Subsequent lack of mRNA leads to deficiency of these proteins necessary for mycobacterial survival. Altered rifampin binding site/altered DNA dependent RNA polymerase
What are the four Rs of rifampin
RNA polymerase inhibitor, Ramps up cyt P450, red/orange body fluids (sweat, urine), rapid resistance If used alone, Rifampin ramps up P450 but rifaBUTin doesn’t
Lung abscesses on CT can be identified by
Presence of air fluid levels
Alocoholics are likely to develop pulmonary infections and abscesses involving which organisms? What tx is appropriate?
Combination of oral anaerobic flora (bacteroides, fusobacterium, and peptostreptococcus) and aerobic bacteria. Clindamycin covers most of these organisms and is antibiotic of choice for treating lung abscesses
What are symptoms specific to Grave’s disease?
Exopthalmos and pretibial myxedema. Can be described as “lower leg skin thickening and induration.”
Name the anticholinesterases
Neostigmine, pyridostigmine, physostigmine, Donepezil/Rivastigmine/galantamine, edrophonium
What drug can counteract both peripheral and CNS effets of atropine
Physostigmine, an anti-cholinestarase, able to cross the blood brain barrier.
HBA2 is elevated in?
Beta thalassemia minor (trait) and intermedia because of underproduction of beta globin chain.
