Heart Failure Flashcards
heart failure definition:
-inability of the heart to pump sufficient blood to meet the metabolic needs of the body
myocardial failure definition:
- defective myocardial contraction
- results in heart failure!
circulatory failure definition:
- a condition in which an abnormality of some circulatory component (heart, vessels, blood volume, etc) is responsible for inadequate cardiac output
ex) hemorrhage
prevalence of heart failure:
- 23million worldwide
- 4.7 million in US (1.5-2%)
incidence of heart failure:
-declining rates!!
What is the neurohormonal mechanism of heart failure:
1) activation of sympathetic nervous system (with a concomitant suppression of parasympathetic NS)
- Inc adrenergic activation = more circulating NE = peripheral vasoconstriction
- dec myocardial NE =we dont know why
- Beta1 stim= inc HR and contractility
- alpha1 stim=mild inc in tropism and peripheral vasoconstriction
2) activation of the renin-angitensin system (happens later)
- decreased renal perfusion
- dec Na in distal renal tubule
- inc adrenergic stim = inc renin release
- more antiotensin I=more antiotensin II = organ fibrosis (heart and kidney) & enhanced NE release
Result of neurohormonal model in HF:
- peripheral arterial constriction
- Na/Water retention
- activation of inflammatory mediators of cardiac remodelling
LV remodelling:
1) dilation and shape change
- neurohormonal activation = changed function/shape
- pressure overload = parallel or concentric hypertrophy
- volume overload = SERIES or eccentric hypertrophy
- action potential prolongs in advanced HF (fetal gene activation)=contractile dysf
- contractile and reg proteins altered
- inc myocardial wall tension (LVEDV rises)
- MV regurg (papillary muscle separation)
Backward HF:
- as the LV fails to completely eject its contents - blood accumulates in the LA
- pressure rises in pulmonary circulation
- trasudation of fluid into the pulmonary interstitium = pulmonary congestion/edema
Forward HF:
- inadequate delivery of oxygen into arterial system (reduced cardiac output)
- results in dec perfusion of vital organs + mental clouding, weakness, and Na/water retention
RV HF -
1) most often a consequence of LV failure with pulmonary congestion
2) results in SYSTEMIC CONGESTION
- hepatomegally, mesentery and bowel edema, leg edema, ascites
- fluid retention becomes generalized in RV failure
LV heart failure is:
-true congestive heart failure due to central venous congestion
Systolic failure (LV):
- abnormal systoic function
- high EDV in ventricles
- poor perfusion –> na and water retained
Diastolic failure (LV)
- abnormal diastolic filing (heart cant fill-heart isnt stretching well)
- high LV filling pressure
- eventual pulmonary and systemic congestion
Pure R side failure due to
corpulmonale!!
Heart failure - precipitating causes:
- ischemia/infarction (MOST COMMON)
- hypertension
- arrhythmias (a fib)
- infectious/inflammatory
- pulmonary embolus
- physical, emotional, environmental stress
- cardiac toxins (chemo,alcohol)
- high output states
- reduction of therapy (LEAST COMMON)
Symptoms of HF:
1) short of breath (progressive)
- exertional
- paroxysmal nocturnal dyspnea
- orthopnea
- resting dyspnea
2) diminished exercise capacity
3) fatigue/weakness
4) nocturia
5) CNS impairment (memory, insomnia)
6) symptoms of RV faiure
Classification of HF:
-class1=no limitation
-class2=slight limitation
(orginary activity causes symtpoms)
-class3=marked limitation
(Less than normal activity precipitate symptoms)
-class4=symptoms at rest
Physical exam of HF patient:
1) pallor, cool extremities
- sympathetic tone causes cutaneous vasoconstriction
2) Anxiety, dyspnea at rest
3) Pulses normal to rapid, weak
- fast pulse from sympathetic tone & low SV
4) blood pressure varies
5) Pulmonary rales as LV fails
6) elevated jugular pulsations in RV failure
7) kussmauls sign in RV failure
- venous return is enhanced with inhalation = jugular veins are distended (normally not)
8) hepatojugular REFLUX
- 60 sec of pressure on dome of liver=jugular venous pulses rise in the neck
9) congestive hepatomegaly
10) edema - symmetrical, pitting, dependent
11) pleural effusion
12) ascites
cardiac exam of HF patient:
- cardiomegaly (apical impulse down and to the left)
- S3 universal
- S4 rare (not usually a poor compliance issue)
- pulsus alternans
- murmurs -systoc (MR, AS, TR) & diastolic (AI)
- cardiac cachexia (late) - so much edema that the abdomen is full of fluid = cant eat
Lab of HF patients:
- electrolyte abn - water excess, renal dysf (hyponatremia-water/Na balance issue)
- liver enzyme elevations
- findings related to precipitating causes (thyroid studies)
X-ray of HF patients:
- cardiomegaly
- pulmonary cogestion
- pleural effusion
- kerley B lines (engorged lymphatics)
ECG and HF patient?
non-diagnostic - can help with ischemia or chamber elargement
HF prognosis:
- pooor bc it just keeps gettig worse
- 1.7 year men and 3.2 years for women post diag
- 5 year for men = 25%
- 5 year for women=32%
most HF patients die from:
pump failure
tachyarrhythmias
worse HF prognosis factors:
- male
- ischemic heart disease (CAD)
- S3
- low pulse pressure
- high functional class
- reduced exercise capacity
hgih output HF-
- high CO but metabolic needs no met
- so much shunting of blood that tissues that need blood dont get it
etiologies of high output HF:
- anemia
- AV fistula (hemo patients)
- hyperthyroidism
- beri-beri
- pagets disease of bone
Goals of HF therapy
- relieve symptoms
- prolong survival
- improve quality of life
- delay or prevent progression of myocardial dysf
common causes of HF:
- CAD (ischemic cardiomyopathy; MI)
- HTN
- valvular disease
- cardiomyopathies
- cor pulmonale
- congenital heart disease
General approach to HF Tx:
- base therapies on Functional class
- reverse potentially treatable problems (CAD=reperfusion;repair structural abn ex valvular disease)
- aggressive screening for DM
- immunize for pneumonia and influenza
- appropriate activity and rest
Meds that make HF WORSE:
- verapamil, diltiazem (neg ionotropic)
- NSAIDs
- sotalol (anti-arrhythmic)
- beta blockers
Functional classes of HF:
- 1=asymptomatic-no activity limit- no Sx
- 2=mild symptoms-slight activity limit-some Sx with ordinary activity
- 3=marked limit of activity-much more Sx with less than ordinary activity
- 4=decompensated - MANY Sx at rest
Heart Failure stages:
- A= high risk for HF - no structural heart disease or Sx (yet)
- B=structural dysf (LVH) but no Sx
- C=structural Dysf (MI) with Sx (SOB) – MOST PEOPLE HERE
- D=refractory HF
Non-drug Tx:
-HF risk factor reduction
-education (smoking, EtOH, dietary Na, fluid intake, monitor WG)
-activity (heavy physical labor is no-no)
for compensated HF (func classes 1-3) regular moderate exercise helps
-Diet- restrict Na
-manage fluid status - make sure they dont drink to much fluid if kidneys and heart is bad
prevent HF progresson by:
1) counteracting neurohormonal activation
- ventricular remodeling due to adrenergic activation
- renin angiotensin aldosterone system activation
- -> relieved symptoms
- -> tabilizes or reverses remodeling
what drugs help with the neurohormonal activation of HF
- angiotensin converting enzyme inh (ACEI) (BEST CHOICE!!!!)
- angiotensin receptor blocker (ARBs)
- beta blocker
How ACEI help:
-interfere with renin angiotensin loop =block effect of angio2 on AT-1 receptors =stabilize LV remodeling =improve symptoms (QOL improved) =reduce/prevent hospitalization =prolong life
ACEI - the drugs:
- captopril
- enalapril
- fosinopril
- lisinopril
- quinapril
- ramipril
THE -PRILS
beta blockers on HF
- not always BAD
- anti-adrenergic agents for chronic HF
- interfere with adverse effects of adrenergic activation on beta1 receptor
- USED WITH ACEI!
Which beta blockers tolerated by HF aptients:
- metoprolol (BETA1 BLOCKER)
- carvedilol (beta1 block with alpha 1 aka vasodil properties)
- bisoprolol )beta1 selective
when do give beta blockers:
-patient is functional class 2 or 3 already on ACEI or diuretic with no contraindications (asthma, AV block)
Spironolactone is used how?
-aldosterone antagonist - only when all other drugs used and not helping enough (lousy diuretic - K sparing/saving!)
other HF tx:
1) Mechanical
- intra aortic balloon pump
- LV assist device
2) Transplant
3) artificial heart!?!
