HLTH 2501: congestive heart failure Flashcards
what is CHF?
occurs when the body is unable to pump sufficient blood to meet the metabolic needs of the body; one side of the heart usually fails first, followed by the other side
what are the causes of CHF?
usually are results of complication of another conditions, but also can be the result of a valve defect, hypertension, or lung disease
what is the main compensation mechanism for CHF?
to maintain cardiac output
how is cardiac output maintained in CHF?
increased renin and aldosterone secretion, SNS activation, and dilation or the heart chambers, along with hypertrophy of the ventricle walls
cardiomegaly
the walls of the ventricle become thicker as a compensation mechanism for CHF
two basic effects when the heart cannot maintain its pumping capability
cardiac output or stroke volume decreases and backup congestion develops
what happens when myocardial cells die?
they are replaced with fibrous tissue
what happens when CO and SV decrease?
less blood reaches other organs and tissues, leading to decreased cell function, fatigue, and mild acidosis
what is backup congestion?
occurs in the circulation behind the affected ventricle when the output from the ventricle is less than the inflow of blood
left-sided CHF
occurs when the left ventricle cannot pump all its blood into the systemic circulation, causing the normal volume of blood returning from the lungs to not be able to enter the left side of the heart; this causes congestion in the pulmonary circulation and possible pulmonary edema
right-sided CHF
the right ventricle cannot maintain its output, so less blood proceeds to the left side of the heart and the systemic circulation; congestion often occurs in the legs, feet, and portal circulation
forward effect signs and symptoms of CHF
fatigue, weakness, dizziness, dyspnea, exercise intolerance, and cold intolerance
dyspnea
shortness of breath
what is the leading cause of CHF
coronary artery disease
how would hypertension cause CHF?
it increases diastolic pressure, requiring the left ventricle to contract with more force to open the aortic valve; this cause the left ventricle to hypertrophy and eventually fail
what is right-sided CHF often caused by?
pulmonary disease
cor pulmonale
right-sided CHF due to pulmonary disease
compensation mechanisms effects of CHF
tachycardia, pallor, and daytime oliguria
daytime oliguria
decreased urinary output
backup effects of left-sided HCF
dyspnea when lying down (fluid accumulates in the lungs), cough due to fluid irritating the respiratory passages, and paroxysmal nocturnal dyspnea
paroxysmal nocturnal dyspnea
occurs during sleep when the increased blood volume in the lungs leads to increased fluid in the alveoli, leading to interference with O2 diffusion and lung expansion; can cause the individual to awake in a panic struggling for air and having hemoptysis
hemoptysis
coughing up blood from your lungs
backup effects of right-sided CHF
edema in the feet, legs, or butt, hepatomegaly, splenomegaly, ascites, flushed face, distended neck veins, headache, and visual disturbances (as a result of acute-right sided failure)
ascites
fluid accumulates in the peritoneal cavity; associated with right-sided CHF
young children with CHF
often is secondary to congenital heart disease; signs include feeding difficulties, difficulty gaining weight, short sleep periods, irritability, cough, wheezing, and flared nostrils; a third heart sound may also be present
gallop rhythm
a third heart sound; sometimes occurs in infants with CHF
tests for CHF
radiographs show fluid in the lungs, cardiac aterhization monitor pressure in the circulation, and arterial blood gases measure hypoxia
lifestyle changes for treating CHF
is aimed at reducing the workload on the heart by avoiding excessive fatigue, stress, and sudden exertion; influenza vaccines can prevent respiratory infections, diet changes focus on decreasing sodium and cholesterol, and increasing waster, protein, and iron
drug treatment for CHF
antianxiety drugs, ACE inhibitors, digoxin, antihypertensives, and diuretics are all commonly used
