Heart Failure Flashcards
Heart Failure
- An abnormal clinical symptom involving impaired cardiac pumping and/or filling
- heart is unable to produce a adequate cardiac output to meet metabolic needs
characteristics of heart failure (4)
- ventricular dysfunction
- reduced exercise tolerance
- diminished quality of life
- shortened life expectancy
Is heart failure a disease?
no, it is associated with long-standing hypertension, coronary artery disease, and MI
Identifying people with possible HF
- decreased exercise tolerance due to:
Dyspnea
General Fatigue
Identifying people with possible HF:
- people with fluid retention:
- abdominal swelling
- peripheral edema
HF may initially be asymptomatic - when will manifestations be found?
- manifestations of HF may have been found during annual physical exam/screening
Cardinal symptoms of HF
shortness of breath, shortness of breath upon exertion, and peripheral edema
Major contributing factors
- HTN
- history of MI or coronary artery disease
Other risk facors
smoking
obesity
high serum cholesterol
diabetes
Caused by any interferences with normal mechanisms regulating CO (5)
- preload
- afterload
- myocardial contractility
- heart rate
- metabolic state of individual
How does it happen?
- abnormal loading conditions
- increased preload (more fluid coming into the heart with venous return) - hypervolemia & septal defects
- increased afterload (hypertension, atherosclerosis)
Cardiomyopathy
ischemic conditions:
- CAD & MI lead to damage of the cardiac muscle
Abnormal ventricular filling
stenosis of mitral or tricuspid valve
High CO demands
- sepsis, severe anemia puts pressure on the heart
Preload
volume of blood in ventricles at the end of diastole (end diastolic pressure)
Afterload
resistance left ventricle must overcome to circulate blood
causes of increased preload:
- hypervolemia
- regurgitation of cardiac valves
- the volume of blood going into the heart
Causes increased afterload
- hypertension
- vasoconstriction
- blood pressure
- stiff arteries
Systolic Failure - most common cause of HF
- inability of the heart to pump blood effectively
Hallmark finding of systolic failure
decrease in the left ventricular ejection fraction (EF) (LV loses ability to generate enough pressure to eject blood through high-pressure aorta)
Ejection Fraction
fraction or % of total volume of blood in the LV that is ejected during each ventricular contraction
- normal value is > 55% of ventricular volume
What EF is considered alarming? And what causes this?
< 40% requires specialist intervention
- caused by myocardial ischemia (dead muscle tissue around the heart), increased afterload, cardiomyopathy, or mechanical abnormalities
Diastolic Failure (HF - PEF) and diagnosing factors
- impaired ability of the ventricles to relax and fill during diastole resulting in decreased stroke volume and CO
- pulmonary congestion, pulmonary hypertension, ventricular hypertrophy, normal ejection fraction
- inability of the LV to relax normally, resulting in fluid backing up in the lungs
Left sided HF (most common)
backup blood into the atrium and pulmonary veins.
manifested as pulmonary edema: SOB, crackles, decreased air entry
Right Sided HF
causes backward blood flow to the right atrium and venous circulation. Resulting in peripheral edema, weight gain, ascites, JVD, hepatomegaly
Manifestation of LHF
- decreased CO, activity intolerance, signs of decreased tissue perfusion
- pulmonary congestion, impaired gas exchange (cyanosis, signs of hypoxia), pulmonary edema (orthopnea, cough with frothy sputum, paroxysmal nocturnal dyspnea)
Compensatory mechanism: ventricular dilation
- enlargement of chambers of heart related to elevated pressure over time.
- cardiac muscle increases in strength and dilates
- initially intended to cope with elevated blood volume -> leads to increased cardiac output and maintanence of BP
- turns into ventricular hypertrophy. Cant keep up
Compensatory mechanism:
- increased sympathetic nervous system stimulation
- 1st mechanism triggered. least effective
- increased epinephrine and norepinephriine -> increased HR, myocardial contractility, peripheral vascular constriction
Compensatory mechanism: Neurohormonal responses
- renal system is particularly sensitive to reduction in BF and renal perfusion.
- activates renin-angiotensin-aldosterone mechanism
Renin-Angiotensin-Aldosterone mechansim
- renin-angiotensin secretion causes vasoconstriction. and release of aldosterone which causes retention of salt & water which increases preload
- bad because it eventually leads to venous congestion and peripheral edema.
Cardiac decompensation
compensatory mechanisms no longer maintaining adequate CO and insufficient tissue perfusion results
Ventricular Remodeling
- hypertrophy of cardiac myocytes (large cells)
- increased ventricular mass - impairs contractility
- bigger, less effective pump
Left Ventricular Failure Manifestations:
- respiratory
- pulmonary congestion
- dyspnea
- bilateral crackles
- frothy productive cough
- hemopytsis
- orthopnea
- acute pulmonary edema
LVF manifestations
- cardiovascular
- pallor and cool skin
- hypotension
- third heart sound
- enlarged ventricle (PMI shift to left)
LVF manifestations - urinary
- decreased output -> oliguria
- nocturia is common
- increased BUN
Right Ventricular Failure manifestations
- cyanosis and cool skin
- weight gain
- ascites
- liver enlargement
- dependent edema
- JVD
General S & S of heart failure
- tachycardia - trying to increase CO
- reduced exercise tolerance
- fatigue
- anorexia and cachexia
- behaviour changes
Acute Decompensated Heart Failure (ADHF)
- compensatory mechanisms fail
- manifests as pulmonary edema, often life threatening
Symptoms of ADHF (8)
- crackles
- severe dyspnea
- fatigue
- shortness of breath
- pink frothy sputum
- increased inspiratory rate
- cyanotic
- cool and clammy skin
Goal of therapy:
improve left ventricular function
How to improve LV function:
- decrease intravascular volume (lasix diuretic via IV push to help the kidneys get rid of fluid)
- decrease venous return - preload (high fowlers, dangling legs)
- improve gas exchange and oxygenation
- improve cardiac unction
- reduce anxiety (morphine - deal with SOB)
Medication Therapy (GOAL)
- identify type of HF
- correction of sodium and water retention overload
- reduction of cardiac workload
- improve myocardial blood supply
Diuretics
- lasix
- reduces preload by reducing intravascular fluid.
- gets rid of potassium - be careful
ACE (angiotensin converting enzyme) inhibitors
- inhibit angiotensin converting enzyme and by doing this lower BP
- 1st line therapy
- vasodilator - decreased systemic vascular resistance. increased cardiac output.
- ramipril
B-Adrenergic blockers
- used with ACE inhibitors to block negative effects of sympathetic nervous systems on the failing heart.
- beta blockers reduce cardiac oxygen demand by reducing HR and BP
- metoprolol
- hold if BP is < 100
Vasodilators: nitrates
- reduces afterload by dilating peripheral blood vessels
- increase myocardial blood supply by dilating cardiac BV
- first-line med management of chest pain
- dangerous in RHF because of drop in preload
Digitalis
digoxin
increases cardiac ouptu
- if below 90 hold drug
assess apical rate of heart
Nursing Diagnosis
- decreased cardiac output (physical assessment - VS, heart sounds, lung sounds, LOC, edema, cap refill, fluid balance, lab values - pharmacological management, adequate rest, strict I&O)
- impaired gas exchange (O2, incentive spirometry and deep breathing, semi-fowlers, diuretics)
- ineffective tissue perfusion (ROM, massage)
- Excess fluid volume (diuretics, watch for hypokalemia, ensure sodium restriction, strict I & O, monitor weight)
- anxiety (Stress management)
- activity intolerance (treatment of infection or other disease processes, promote sleep, prioritize activities)
Emergency toxicity
- Digitalis toxicity
- bradycarida, tachycardia, irregular pulse/arrhythmias
Nursing Interventions for Pulmonary Edema
- patency of IV saline lock
- in case they need IV meds
