Heart failure Flashcards
Heart Failure
•Inability of the heart to pump sufficient blood to
meet the needs of the tissues for oxygen and
nutrients
•A clinical syndrome characterized by signs and
symptoms of fluid overload or of inadequate tissue
perfusion
• Signs & symptoms results when the heart is unable
to generate a Cardiac Output sufficient to meet the
body’s demands
Heart Failure continued…
• Most often this is a life-long diagnosis that is managed with lifestyle changes and medications to prevent acute congestive episodes • Congestive heart failure (CHF) is usually an acute presentation of heart failure (HF)
HF
- Incidence increases with age
- Incidence similar in men & women
- The most common reason for hospitalization in adults over 65 yrs
- Medical management is based on the type, severity and cause of HF
Signs & Symptoms
SOB swelling of legs chronic lack of energy difficulty sleeping at night due to breathing problems swollen or tender abdomen with loss of appetite cough with frothy sputum increased urination at night confucion and or impaired memory
Types of HF
Two types identified by assessment of left ventricular functioning
- Systolic heart failure – alteration in ventricular contraction
- Diastolic heart failure – alteration in ventricular filling
Pathophysiology of HF
Results from a variety of CV diseases but leads to some common
abnormalities that result in:
o decreased contraction (systole),
odecreased filling (diastole)
o or both
• Significant myocardial dysfunction usually present before patient
experiences signs & symptoms of HF
Systolic Failure
• Most common cause of HF
• Left ventricle loses ability to generate enough pressure to eject blood
forward through the high pressure aorta
• Heart muscle contracts weakly so not enough oxygenated blood
being pumped throughout body
• Caused by impaired contractile function e.g.. MI, hypertension,
cardiomyopathy & cardiac valve disease
Diastolic HF
•Impaired ability of ventricles to fill during diastole
resulting in decreased stroke volume (amt of blood
pumped by ventricle with each contraction)
• Contractions are normal but ventricle doesn’t relax
completely so less blood enters the heart
• Characterised by high filling pressures & resultant
venous engorgement in both pulmonary and
systemic vascular systems
•Usually the result of LV hypertrophy from
hypertension
Left-sided Failure
Most common form
• Inadequate cardiac output from the left ventricle to supply sufficient
blood for the body’s needs. Backward effects include pulmonary
congestion & oedema.
• ↑ pulmonary pressure causes fluid to escape from the pulmonary
capillary bed into the alveoli
Right-sided Failure
• Primary cause is L) sided failure
• Inadequate cardiac output from the right ventricle
• Causes backward flow to the right atrium and venous circulation
• Venous congestion in the systemic circulation results in peripheral
oedema, hepatomegaly, splenomegaly, vascular congestion of GI
tract & jugular vein distension
Pathophysiological Rationale for clinical
manifestations of CHF
Dyspnoea - ↑ pulmonary pressure secondary to
interstitial and alveolar oedema
•Dry hacking cough or frothy sputum – fluid in lungs
•Nocturia – A person with CHF has ↓ CO & impaired
renal perfusion & ↓ urinary output during the day.
When the person lies down at night, fluid
movement from interstitial spaces back into the
circulatory system is enhanced. This causes ↑ renal
blood flow & diuresis. Person may have to void
urine 6-7 times per night
Pathophysiological Rationale for clinical
manifestations of CHF continued…
•Dependant oedema - Venous congestion in the systemic circulation. Sacral oedema is present if the patient is in bed •Anorexia & gastro-intestinal bloating - Abdominal fullness from ascites and hepatomegaly
What can happen with failure of L) side of
heart?
L) sided failure results from LV dysfunction which causes blood to back up through the left atrium and into the pulmonary veins The increased pulmonary pressure causes fluid extravasation from the pulmonary capillary bed into the interstitium and then the alveoli, which is manifested as pulmonary congestion and oedema
What can happen with failure of R) side of
heart?
•R)sided failure causes backward flow to the right
atrium and venous circulation
•Venous congestion in the systemic circulation
results in peripheral oedema, hepatomegaly,
splenomegaly, vascular congestion of the GI tract
and jugular venous congestion
Describe the Oedema of CHF
•May occur in the: • legs (peripheral oedema) • liver (hepatomegaly) • abdominal cavity (ascites) • lungs (pulmonary oedema and pleural effusion) •pitting oedema may be present
