Rx_1.11 (Cardio) Flashcards Preview

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Flashcards in Rx_1.11 (Cardio) Deck (20)
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1

Feature/Dx?

  • Aschoff module = perivascular fibrinoid necrosis
  • Dx = rheumatic heart disease (rheumatic fever)

2

Cardiac consequences of rheumatic fever

  • autoimmune insult @ mitral valve ==>
    • mitral stenosis + 
    • heart murmer
  • pathology: aschoff nodule = perivascular fibrinoid necrosis
  • w/excessive strain on heart/cardiovascular system ==> heart failure 

3

Patient from developing country + murmur + suden death ==> dx?

Most likely Rheumatic heart disease

4

Presentation of PDA

  • wide pulse pressure
  • excercise intolerance
  • continous machine-like murmur

5

Important risk factor for PDA

  • congenital rubella
  • mother during pregnancy:
    • maculopapular rask @ face ==> body 

6

Organisms that can cross placenta ==> congenital disease

  • ToRCHeS:
    • Toxoplasmosis
    • Rubella
    • Cytomegalovirus
    • Herpesvirus/HIV
    • Syphillis 

7

Cardiac drugs to avoid in DM patients taking sulfonylurea (glipizide)

  • beta-blockers (e.g. metoprolol)
    • can mask hypoglycemia (possible complication of DM drugs like sulfonylurea)

8

MOA of sublingual tablet used to tx activity-induced chest pain

  • drug = Nitroglycerin
  • MOA = 
    • Nitric oxide ==> vasodilation via cGMP-dependent mechanism
    • @ low dose: venodilation ==> decreased preload ==> decreased myocardial O2 demand
    • @ high dose: venous + arteriolar dilation ==> decreased afterload
      • can ==> hypotension and reflex tachycardia

9

Adverse effects of Nitroglycerin

  • development of tolerance
  • dilation of facial and menigeal arterioles ==> 
    • flushing
    • headache

10

Tx of acute exacerbations of CHF w/pulmonary edema

  • Loop diuretics
    • furosemide

11

Characteristics of "brown atrophy"

  • acummulation of lipofuscin @ heart, liver, or spleen
  • lipofuscin =
    • "wear and tear" pigment
    • oxidized and polymerized membrane lipids from autophagocytosed organelles
  • benign finding @ elderly

12

Direct-acting vs. indirect-acting sympathomimetics 

  • direct (e.g. isoproterenol):
    • postsynaptic adrenergic receptors
    • no interaction w/presynaptic neurons
    • more selective for receptor activity
  • direct (e.g. amphetamine):
    • presynaptic adrenergic receptors
    • no interaction w/postsynaptic neurons
    • ability to enter CNS ==> undesirable stimulation
    • less selective for receptor activity

13

Mechanism of constriction of pupil

  1. calcium-calmodulin complex activates myosin light-chain kinase
  2. myosin light-chain kinase phosphorylates myosin
  3. myosin binds to actin

14

Tx for elevated lipids + body pains + weakness + elevated creatine kinase ==> Dx?

  • Dx = myositis or rhabdomyolysis 
  • complication of tx w/ statin + fibric acid derivative (e.g. gemfibrozil)

15

Effects/MOA of digoxin

  • MOA = inhibition of Na-K pump ==> increased intracell Na ==> reduces Ca extrusion via Na-Ca exchange ==>
    • increased contractility (inotrope)
      • ==> decreased end-systolic vol.
      • ==> increased ejection fraction
    • ==> CO
      • ==> decreased sympathetic activity ==> reduced vascular resistance

16

Amiodarone: MOA, adverse effects

  • MOA = blocks K channels ==> prolonged refractory period
  • adverse effects
    • pulmonary fibrosis
    • thyroid dysfxn
    • ataxia
    • neuropathy

17

Common cause of sudden cardiac death in setting of MI

  • arrhythmia
  • usually ventricular tachyarrhthmias 
    • ventricular fibrillation

18

Norepinephrine MOA

  • sympathetic agonist @ a1, a2, and B1 receptors
    • a1 ==> vascular constriction
    • B1 ==> inotropy @ heart

19

Good antagonist for effects of norepinephrine

  • Labetalol =
    • non-selective blocker of alpha and beta adrenergic receptors

20

Vasculitis associated w/smoking

  • Buerger's disease
    • small- to medium-vessel vasculitis
    • presents ~ as peripheral arterial disease
      • decreased distal pulses compared to proximal 
      • cold, painful distal extremities (often hands)

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