Clinical Treatment of HF

Question 1

Major goals of HF therapy (6)

Answer 1

• Correction of the underlying cause of HF
  
  • e.g. revascularize in case of ischemia
• Elimination of precipitating factors
• Reduction of congestion (fluid optimization is a major part of HF therapy)
• Improve flow (may be difficult to do medically)
• Modulate neurohormonal action
  
  • Long-term stabilization, positive remodelling, increased survival.
• Optimization of cardiac function

Question 2

Major classes of medication for HF (4)

Answer 2

• diuretics
• vasodilators
• neurohormonal antagonists
• inotropes

Question 3

Function of diuretics in tx of HF

Answer 3

• reverse the sodium and fluid retention of HF
• fxn @ far end of the frank-starling curve, such that significant decreases in pressure produce minimal changes in stroke volume (and thus CO)
• symptoms of congestion can be reduced without major effects on blood flow

Question 4

Fxn of various types of vasodilators in tx of HF

Answer 4

• Vasodilators: arterial, venous, and pulmonary arterial vasodilation
• Arterial: ↓ LV afterload, ↓ cardiac work, ↓ mitral regurgitation
• Venous: ↓ preload
• Pulmonary: ↓ RV afterload

Question 5

Types of neurohormonal antagonsists

Answer 5

• ACE inhibitors
• Angiotensin receptor blockers (ARBs)
• Aldosterone receptor blockers
• Beta-blockers

Question 6

ACE inhibitors fxn in tx of HF (+side effects)

Answer 6

• block conversion of ATI to ATII→direct vasodilation, decreased aldosterone activation
• Side effects: hypotension, worsening renal failure, hyperkalemia, cough (kinin production), angioedema

Question 7

Angiotensin receptor blockers fxn in tx of HF

Answer 7

• blocks receptor of ATII→ equivalent to ACE -Is, but without cough.

Question 8

Aldosterone receptor blockers fxn in tx of HF

Answer 8

• block aldosterone action in kidney→↓sodium→diuretic
• anti-remodeling activity at the level of the heart

Question 9

Beta-blockers fxn in tx of HF (+side effects)

Answer 9

• antagonize effects of the sympathetic nervous system→↓chronotropy ↓inotropy (short term loss for long term gain)
• Side-effects: bronchoconstriction

Question 10

Fxn of Inotropes in tx of HF (& major types)

Answer 10

• administered via IV agents short term in the ICU to reverse shock (long term—worsen remodelling ↑mortality)
• Digoxin—K/Na exchanger
• Dobutamine—beta agonist
• Milrinone—PDEi (posphodiesterase inhibitor)

Question 11

Electrical therapies used for HF (2)

Answer 11

• defribrillators
• resynchronization

Question 12

Fxn of defribillators in tx of HF

Answer 12

• for patients with LVEF < 35% or with prior dangerous rhythms. Implanted.
• Abort sudden cardiac death from ventricular tachycardia/fibrillation.

Question 13

Fxn/procedure of resynchronization in tx of HF

Answer 13

• Left ventricular lead placed from the RA through the coronary sinus over the epicardium of the LV (3 leads: RA, RV coronary sinus/LV)
• For patients with QRS > 120 msec (bundle branch block)
• Cause the lateral wall and septal wall to contract together, which produces:
  
  • More efficient contraction→↑stroke volume
  • May also improve mitral valve function→↓regurgitation

Question 14

Advanced therapies for tx of HF

Answer 14

• Transplantation: shortage of organs.
• Mechanical support devices: often used as a bridge to transplantation or as a destination therapy.
• Hospice: palliative advanced therapy→paradigm shift from quantity to quality of life

Question 15

Therapy goals/Tx for Stage A HF

Answer 15

• Stage A: at risk for HF but without structural disease or symptoms
• Therapy goals: treat hypertension, smoking cessation, treat lipid disorders, regular exercise, discourage alcohol intake, drug use, control metabolic syndrome
• Drugs: ACEi or ARB in appropriate patients.

Question 16

Therapy goals/Tx for Stage B HF

Answer 16

• Stage B: structural heart disease but without signs or symptoms of HF.
• Therapy goals: same as stage A
• Drugs: ACEi, ARB, beta-blockers
• Devices: implantable defibrillators

Question 17

Therapy goals/Tx for Stage C HF

Answer 17

• Stage C: structural heart disease with prior or current symptoms of HF.
• Therapy goals: same as stage A and B + dietary salt restriction.
• Routine drugs: diuretics, ACEi, beta-blockers
• Drugs in selected patients: aldosterone antagonist, ARBs, digitalis, hydralazine/nitrates
• Devices: biventricular pacing, implantable defibrillators

Question 18

Therapy goals/Tx for Stage D HF

Answer 18

• Stage D: refractory HF requiring specialized interventions
• Therapy goals: A, B, and C + end of life decisions regarding the appropriate level of care.
• Options: compassionate end-of-life care/hospice or extraordinary measures
• extraordinary measures: transplant, chronic inotropes, permanent mechanical support, experimental surgery/drugs.

Question 19

Type of HF which most pharmacological treatments are used for

Answer 19

• Most treatments are designed and indicated for patients with reduced ejection fraction (HFrEF)
• However, 50% of pts w/HF have HFnEF (normal ejection fraction)

Question 20

Tx for pts w/HFnEF

Answer 20

• Trials for neurohormonal antagonists have not been successful in improving outcomes for patients with HF and normal ejection fraction.
• ICD/CRT are not generally indicated in patients with LVEF > 35-40%
• Therapy consists of treating the underlying disorder—hypertension, diabetes, kidney dysfunction, aortic stenosis.
• Diuretics are used to keep volume normal (sodium retention is common)
• Vasodilators are used to maintain normal blood pressure.

Question 21

Conditions that most often lead to heart disease/HF (6)

Answer 21

• Hypertension
• Diabetes
• Hyperlipidemia
• Physical inactivity
• Excessive alcohol intake
• Excess dietary sodium