Rx_01.17 (Cardio) Flashcards Preview

USMLE Step 1 > Rx_01.17 (Cardio) > Flashcards

Flashcards in Rx_01.17 (Cardio) Deck (23)
1

Categories of Ca-channel blockers + examples

  • Non-dihydropyridine
    • verapamil
    • diltiazem
  • Dihydropyridine
    • amlodipine
    • nifedipine
    • nimodipine

2

Effects of non-dihyrdopyridine ca channel blockers

  • e.g. verapamil, diltiazem
  • potent effects on heart rate and contractility
    • block L-type Ca channels ==> decreased m. contractility
  • less effects @ vascular smooth m. compared to dihydropyridine

3

Effects of dihyrdopyridine ca channel blockers

  • e.g. amlodipine, nifedipine, nimodipine
  • less-potent @ heart
  • more potent @ vascular smooth muscle
    • ==> vasodilation

4

Causes of dilated cardiomyopathy

  • ABCCCD (B C w/A C D C)
  • alcohol abuse
  • wet Beriberi
  • Coxsackie B myocarditis
  • chronic Cocaine
  • Chagas
  • Doxorubicin (Hodgkin's lymphoma tx)

5

Adverse effects of fibrates

  • myositis
  • hepatotoxicity
  • cholesterol gallstones

6

Fxn of thrombaxane + chemical source

  • Arachidonic acid acted on by COX ==> endoperoxides ==> thromboxane A2 ==>
    • increased platelet aggregation
    • increased vascular tone
    • increased bronchial tone

7

Fxn of B-blockers @ heart

  • B-blockers inhibit GPCR ==> 
  • decreased cAMP/PKA ==?
  • decreased Na and Ca current @ AV node ==>
  • decreased slope of phase 4 and phase 0
  • help to suppress abnormal pacemakers

8

Adverse effects of ACE inhibitors 

  • e.g. captopril
  • hypotension
  • hyperkalemia
  • renal insufficieny
  • angioedema
  • metallic taste
  • fetal renal damage
  • cough

9

Cause of referred pain in MI

  • viisceral sensory pain fibers synapse @ thoracic dorsal root danglia
  • these synapses enter @ the same level as the brachila plexus ==> pain perceived in shoulder/neck

10

Characteristics of Mannitol

  • osmotic diuretic
    • ==> preferential water diuresis
  • can cause pulmonary edema ==> contraindicated in patients w/CHF

11

MOA of Digoxin

  • inhibits Na-K-ATPase pump ==>
  • increase in intracell [Na] ==> inhibition of Na/Ca antiporter ==> increased intracell [Ca] ==>
  • positive inotropic effect @ heart + increased vascular resistance + increased systemic BP

12

Phases of cardiac cycle?

  • I = ventricular filling
  • II = isovolumetric contraction
  • III = centricular ejection
  • IV = isovolumetric relaxation

13

Fibrous plaques = ?

  • atherosclerosis
    • intimal plaques w/necrotic lipid core

14

Medial calcific sclerosis of arteries = ?

  • Monckeberg's arteriosclerosis
    • calcification of media of medium-sized muscular arterias
    • no intimal thickening or obstruction of flow

15

Norepinephrine: MOA, SE

  • action at a-receptors ==> vasoconstriction ==> elevated systemic resistance/BP
  • stimulation of B1 receptors ==> increased heart contractility
  • SE: reflex bradycardia (in response to increase venous return and contractility)

16

Embryonic orgins of smooth portions of ventricles

bulbus cordis

17

primitive atrium ==>

trabeculated regions of atria

18

trabeculated portions of ventricles derive from which embryonic structure?

primitive ventricle

19

Embryonic formation of smooth parts of atria

  • sinus venosis ==> coronary sinus + smooth parts of RA
  • portions of pulmonary veins ==> smooth LA

20

Embryonic formation of aorta/pulmonary artery

  • truncus arteriosus ==> aorta + pulmonary artery
  • neural crest cells ==> aorticopulmonary septum

21

Chronic exposure to industrial chemicals ==>

  • nitroglycerin exposure ==> nitroglycerine withdarawal
    • "monday disease" of headaches, dizziness, palpitations
  • can lead to compensatory vasoconstriction @ coronary arteries ==> non-atherosclerotic ischemia ==> cardiac arrest

22

Cardiac drug contraindicated in cocaine users

  • beta-blockers 
  • B-blocers + cocaine ==> unopposed alpha effects ==> excess vascular smooth m. contraction

23

VHL inheritence + gene location

  • autosomal dominent 
  • VHL = deletion of tumor suppressor gene on chromosome 3p

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