chapter 20- HF Flashcards
Heart Failure
complex syndrome of the heart that results from functional or structural impairment of ventricular filling or ejection of blood into the circulation.
*Assoc. with either a reduced or preserved L Ventricular EF
Compensatory Ability
- how your body pumps just sitting around vs running a marathon
- CO^: Exercise
Cardiac Reserve
how much the heart compensates to increase output during exercise
Myocardial Contractility
(inotrophy)
- the contractile performance of the heart (actin and myosin)
- as contractility ^, CO ^
Preload
Afterload
P- Amt. of blood in ventricles at the end of diastole
A- measure of force that was required to eject the blood from the ventricles
Ejection Fraction
the % of total amount of blood that entered ventricle that is actually moved out. (normal: 60%)
Most common causes of HF
coronary artery disease, hypertension, dilated cardiomyopathy, valvular heart disease
Efficiency of the heart is determined by:
the volume of blood that ejects each minute
Frank Starling Mechanism
*activation of neurohumoral influences: SNS and RAAS,
the naturetic peptides, vasoactive substances, hypertrophy and remodeling of heart
- Firs minutes- hours: SNS keeps heart pumping, RAAS is released to vasoconstrict and retain water
- Weeks: myocardial hypertrophy and remodeling for long-term adaptation to hemodynamic overload.
Heart Failure with reduced EF stimulates:
- RAAS pathway
- body retains water and sodium in kidney which ^ vascular volume and venous return to heart
- causes PULMONARY CONGESTION
Natriuretic Peptides (NP)
- naturally released in body response to overstretching of atria or ventricles (Heart Failure)
- inhibits SNS, RAAS, and ADH
- ANP & BNP levels are ^ in HF patients
A Nat Peptide
B Nat Peptide
A- released from ATRIAL cells in response to stretch, pressure, or fluid overload
B- secreted by VENTRICLES in response to ^ ventricular pressure or fluid overload
Both types of NP are released in response to:
^ chamber stretch and pressure
* promotes rapid and transient natriuretesis and diuretics through an increase in glomerular filtration rate and inhibit tubular sodium and water reabsorption
NP’s inhibit the natural response to heart failure: ___ and ___
SNS and RAAS (antidiuretic hormone and vasopressin)
the activation of SNS releases: ___
Catecholamines
-Epinephrine and Norepinephine to ^ HR and ^ CO
Enodthelins
Vasoconstrictors released from endothelium
Induce myocyte hypertrophy and fibrosis
bolster effects of hypoxic kidneys
-counteract BNP and ANP to encourage water and salt absorption in kidney
myocardial hypertropohy and remodling
cells change size to keep up with the demand
- last step in heart compensation to HF
Concentric Hypertrophy
Eccentric Hypertrophy
Concentric: caused by pressure overload
*myocytes get wider, heart walls get thicker
Eccentric: caused by volume overload
*myocytes get longer, heart walls get thinner
Types of Heart Failure:
- Systolic (HRrEF)
- Diastolic (HRpEF)
- Left Sided
- Right sided
Systolic (HRrEF) Failure:
- not pumping out enough during systole (reduced EF) despite a normal BP (EF <40%)
- Causes: volume overload, pressure overload, contractile function impairment
*Effects: Eccentric Hypertrophy, Increased blood volume: Pulmonary Congestion
Symptoms of Systolic HF
dyspnea, fatigue, JVD, peripheral edema, orthopnea, Paroxysmal Nocturnal Dyspnea
Diastolic (HRpEF)
- preserved EF- reduced/abnormal filling of ventricle
- EF (>50%) but ventricle doesn’t fill all the way to EF goes down
- causes of diastolic HF: pericardial effusion, constrictive pericarditis, myocardial hypertrophy (^ wall thickness), AGING, HYPERTENSION
Systolic failure vs Diastolic failure
S: impaired ability to eject blood at a rate commensurate with the metabolic needs of the tissue
D: resistant to filling of one or both ventricles leading to symptoms of congestion
Diastolic HF can be aggravated by ____
tachycardia (wont let the ventricles fill all the way)
Symptoms of Diastolic HF
pulmonary congestion, decrease in lung compliance, ^ in workload and breathing: dyspnea.
____ determines how much time there is for ventricular filling.
Heart Rate
Left-Sided Heart Failure
Diastolic: LV doesn’t accept enough blood from lungs
Systolic: LV doesn’t pump enough blood to body
in Left Sided HF, the blood backs up from__ to:
LV –> pulmonary veins –> Lungs –> pulmonary arteries –> right atria/ventricles –> body
Left-sided HF causes:
- pulmonary edema, dyspnea
* Paroxysmal Nocturnal Edema- trouble breathing when sleeping due to ^ fluid in the lungs
Left-sided HF is attributed to:
- Hypertension
- Acute MI
- Valvular Defects
Right-Sided Heart Failure
Diastolic: RV doesn’t accept enough blood from body
Systolic: RV doesn’t pump enough blood to lungs
In Right Sided HF, the blood backs up from ___ to:
RV –> Inferior/Superior Vena Cava –> LV —> lungs
Right-Sided HF causes:
- Left sided heart failure- L ventricular filling
- isolated R side failure- not common, occurs in ppl with lung disease or pulmonary hypertension, tricuspid valve disease, R ventricular infarction, or cardiomyopathy
Cor Pulmonale
Right Ventricular HF that occurs in response to chronic pulmonary disease
Right-Sided HF symptoms:
- ^ in RV diastolic and end-diastolic: EDEMA
- back up of blood in Inferior and Superior Vena Cava:
Hepatomegaly & Splenomegaly - Congestion of GI tract: anorexia and discomfort
- JVD- can be seen sitting down or standing up
Symptoms of HF for both sides: (5)
- Edema
- Dyspnea- (Cheyne-stokes) respiration
- Cachexia- malnutrition & tissue wasting that occurs at end stage HF
- Cyanosis- blue coloring of skin and mucous membranes
5 Arrhythmia & sudden cardiac death- A fib
Diagnosis of HF
- History
- Physical Exa
- Lab testing ( ^BNP, ^ electrolytes
- Imaging- electrocardiogram
Acute HF treatment
Chronic HF treatment
A- stop the underlying cause
C- relieve symptoms, reduce further damage/reverse damage thats happened. Long term plan
Treatment for all HF
- Exercise
- Drugs (diuretics, B-adrenergic inhibitors, ACE inhibitors)
- Oxygen (CPAP force air into cells/lungs)
- Invasive Methods: LVAD Left Ventricular Assist Device
Increased electrolytes in HF signifies:
- impaired renal function
- higher than normal electrolyte levels means kidneys are reabsorbing water and sodium
- HF
cardiac output is the ___ each minute
blood pumped
in shock, one of the best indicators of blood flow to vital organs is:
urine output
A common symptom of ischemia associated with gastrointestinal redistribution of blood flow is:
gastric bleeding
which type of shock might intravenous therapy be distributed for?
Distributive shock
