CHF 2

Question 1

causes of acute decompensated heart failure

Answer 1

1. increased preload (accounts for most symptoms):
   -increased sodium intake → fluid retention
   -increased fluid intake
   -noncompliance with diuretics
   -change in meds
   -IV fluids
   -increased sympathetic stimulation
2. increased afterload (reduces SV):
   -medical noncompliance
   -increased sodium intake → increased BP
   -increased sympathetic stimulation
3. decreased contractility

Question 2

treatment strategy of acute decompensated heart failure - overview

Answer 2

*improve symptoms, particularly breathing (decreasing preload):
-DIURETICS → get rid of excess fluid
-nitroglycerin to lower venous pressures and reduce pulmonary edema

*increase cardiac output (decrease afterload and/or increase contractility):
-increase blood flow to kidneys to help urinate off excess fluid
-decrease sympathetic & neurohormonal activity
-reduce systemic vascular resistance

Question 3

afterload graph in heart failure

Answer 3

*mild CHF: stroke volume starts to become impacted by higher blood pressure much more quickly than normal heart
*severe CHF: stroke volume is reduced even in the normal range

Question 4

warm & wet CHF: treatment strategies

Answer 4

*DIURETICS (furosemide)
*VASODILATORS (nitroprusside, nitroglycerin, nesiritide)

Question 5

cold & dry CHF: treatment strategies

Answer 5

*INOTROPIC DRUGS (dobutamine, milrinone)

Question 6

cold & wet CHF: treatment strategies

Answer 6

*MECHANICAL SUPPORT
*vasodilators/diuretics, inotropic drugs?

Question 7

heart failure results from:

Answer 7

*decreased compliance
*decreased contractility
*increased preload
*increased afterload

Question 8

diuresis for treatment of heart failure

Answer 8

*diuresis decreases preload and decreases left atrial pressure → decreased LV EDP → symptom improvement
*examples of diuretics: furosemide, bumetanide

Question 9

nitroglycerin for treatment of heart failure

Answer 9

*nitroglycerin decreases preload by venodilation → decreased left atrial pressure → decreased LV EDP → symptom improvement

Question 10

decreasing afterload to treat heart failure

Answer 10

*ACE inhibitors (-opril), ARBs (-sartan), hydralazine, and nitroprusside are all medications that can be used to DECREASE AFTERLOAD
*decreased afterload → decreased LV ESV → INCREASED STROKE VOLUME
*a decrease in afterload shifts the Frank-Starling curve up, which means for a given LV volume, there is a higher stroke volume

Question 11

inotropic therapy for treating heart failure

Answer 11

*dobutamine & milrinone are medications that can be used to INCREASE INOTROPY
*increased inotropy → decreased LV ESV → INCREASED STROKE VOLUME
*an increase in inotropy shifts the Frank-Starling curve up, which means for a given LV volume, there is a higher stroke volume

Question 12

beta blockers for treatment of heart failure

Answer 12

*in acute CHF, beta blockers are usually not started as they may transiently make the volume status worse
*if someone is on them already, they are often continued at a lower dose
*recall: beta blockers end in “-lol”

Question 13

long-term goals for treatment of chronic CHF

Answer 13

1. prevent progression of disease
2. prevent morbidity (hospitalization, functional class)
3. prevent mortality

note - we start treatment in those with stage B CHF

Question 14

stage B CHF long-term treatment

Answer 14

*ACE inhibitors or ARBs
*beta blockers
*sodium-glucose transport inhibitors (SGLT-2i)

Question 15

stage C CHF long-term treatment

Answer 15

*stage B treatment (ACE inhibitor/ARB, beta blocker, SGLT-2i) PLUS:
-aldosterone antagonist
-hydralazine nitrates
-CR + ICD

Question 16

stage D CHF long-term treatment

Answer 16

*consider LVAD/transplant

Question 17

life-prolonging medical therapy for chronic CHF

Answer 17

*ARB + neprilysin inhibitors, ACE inhibitors or ARBs
*beta blockers
*aldosterone antagonists (class III or class IV)
*sodium-glucose cotransporter-2 inhibitor

note - the combination of hydralazine & isosorbide nitrate is recommended for African-Americans with class III-IV HF in addition

Question 18

which calcium channel blocker should we avoid in CHF

Answer 18

*avoid verapamil (non-dihydropyridine CCB blocker) b/c it limits contractility

Question 19

implantable cardiac defibrillators (ICDs) for chronic CHF

Answer 19

*a specific type of pacemaker that is implanted near the heart to automatically defibrillate life-threatening heart rhythms
*used in patients in heart failure with reduced ejection fraction
*shocks the patient if they go into a ventricular dysrhythmia

Question 20

what is the most important risk factor for sudden cardiac death (SCD)

Answer 20

*LV EJECTION FRACTION (esp if LVEF < 30%)

Question 21

ICD class I recommendations

Answer 21

*ischemic cardiomyopathy who are at least 40 days post-MI with an LVEF of 35% or less
*non-ischemic (chronic) ~ 6 months with an LVEF of 35% or less
*high risk of SCA due to genetic disorders such as long QT syndrome, Brugada syndrome, hypertrophic cardiomyopathy, and arrhythmogenic right ventricular dysplasia (ARVD)

Question 22

cardiac resynchronization therapy (CRT)

Answer 22

*electrophysiologist threads an electrical wire through the coronary sinus to the LV free wall and plug it into the LV through one of the cardiac veins
*ensures that you are pacing the septum and the free wall to coordinate the 2 walls of the ventricle

*in patients with a left bundle branch block (QRS > 150 ms) and class II-IV heart failure with a reduced LV EF < 35%, CRT may improve LV function by pacing LV free wall

Question 23

CRT class I recommendations

Answer 23

*refractory LV dysfunction with a LV ejection fraction less than 35% with class II-IV heart failure
*left bundle branch block greater than 150 ms