CHF

Question 1

TZD diuretics

Answer 1

thiazides: inhibit NaCl symporter in DCT » decreased volume + vasodilation;
ineffective in renal impairment (require excretion);
good for hypertension

SEs: hypoK, postural hypoTN, gout, impaired glucose control

Question 2

Loop diuretics

Answer 2

loop: LoH, inhibit Na/K/Cl symporter; good for oedema; can be IV

SEs: electrolytes (Mg, K, Na decreased), postural hypotension, polyuria, gout

Question 3

ACEI (and ATRA)

Answer 3

block RAAS » decreased symptoms (vcon and fluid), decreased remodelling, improved prognosis and reduced mortality; start low go slow

SEs: cough, hyperK, first-dose hypotension, renovascular (CI)

Question 4

BB

Answer 4

neg chronotrope and inotrope; decreased SANS; decreased symptoms and remodelling, improved prognosis and QoL; start low go slow, initial worsening

SEs: bradycardia, initial worsening, bronchospasm (asthma CI)

Question 5

Digoxin

Answer 5

neg chronotrope and pos inotrope; decreased HR (impairs AVN, increases vagal); improves Sx (no mortality effect); used in refractory disease

SEs: arrhythmia (CI: bradycardia, heart block), toxicity (N&V, altered vision)
*reduce dose with interactions: amiodarone, verapamil

Question 6

Management of CHF

Answer 6

symptoms = diuretic (increase dose)
ACEI + BB
add ARA;
adddigoxin/ivrabradine

return of symptoms: first check compliance and repeat tests

asthma: not BB, consider ivrabradine
AF: choose BB (also treats)
renal function: reduce doses

Question 7

warfarin

Answer 7

inhibits VKORC » II, VII, IX, X inhibition; post-ribosomal carboxylation of glutamic acid (extrinsic pathway PT/INR);

uses: venous thrombosis, or heart causes; stroke/MI prevention
SEs: interactions, bleeding, delated onset/cessation
monitoring: INR
CI: preggo, liver, IVDU (erratic), malignancy
reversal: vitamin K or FFP (CF infusion)
interactions:
-inducers: PC BRASS (pheny, carba, BZD, rif, alcohol (C), SJW, sulphonyurea
-inhibitors: macrolides, cimetidine, cipro/quino, amiodarone, doxy, steroids, PPI, fibrates

Question 8

Heparins

Answer 8

activated antithrombin III » no activation of IX, X, XI, IIa; serine proteases (intrinsic pathway APTT); non-teratogenic;

uses: unstable angina, ACS, DVT/PE, warfarin, thromboprophylaxis
SEs: HIT, bleeds, hypoaldo, hypersensitivity
monitoring: platelets, APTT (UF)
reversal: protamine

Question 9

Aspirin

Answer 9

irreversible inhibition of platelet COX » no endoperoxides » no TXA2 (thromboxane) » no aggregation or vasoconstriction;

uses: secondary prevention of MI, stroke; AF
SEs: ulcers and bleeds risk; don’t use with other NSAIDs

Question 10

Clopidogrel

Answer 10

inhibits ADP-receptor » no GP IIb/IIIa induction » no aggregation; reversible (competitive inhibition);
can be used instead of/in combo with aspirin

Question 11

AF management

Answer 11

RATE CONTROL:

• BETA-BLOCKERS:
  
  • slow HR (blocks AVN impulses)
  • no reversal of AF but decreased HR
  • SEs: dizzy/light-headed, fatigue, sleeping issues
• RL-CCB:
  
  • avoid in systolic HF due to neg- inotrope effects
  • option if BB CI (e.g. asthma)
  • SEs: heart failure, lightheaded, ankle oedema/swelling
• DIGOXIN:
  
  • increased contraction and decreased AVN conduction
  • only controls ventricular rate at rest
  • need to monitor HR (

Question 12

Bleeding risk calculations: HASBLED and CHADVASC

Answer 12

CHA2DS2-VASc: risk of stroke; offer PPx if score >2, and >1 if male
-CCF, HTN, Age >75, DM, past stroke/TIA/T-E, Vascular disease, female gender

HAS-BLED: risk of bleeding on warfarin; address modifiable criteria; >3 = closer monitoring needed

• uncontrolled hypertension, abnormal LFTs, abnormal renal function, past stroke,
• bleeding Hx/predisposition, labile INR, elderly (>65), drugs (anti-platelets/NSAIDs), alcohol use (>8 units/wk)