Lecture 10 "Heart Failure" Flashcards
what is the most common etiology of heart failure?
ischemic cardiomyopathy
what is the most common etiology of heart failure in younger people?
dilated cardiomyopathy
metabolic cardiomyopathy is caused by what?
hypothyroidism
what happens to calcium transport in heart failure?
decreased Ca transport, and decreased Ca store in SR
upregulation of Na/Ca exchangers
what happens to potassium flow in heart failure?
downregulation of K channels
increased risk of DADs
what is compensated heart failure?
filling pressure is increased, but it is compensated via the frank-starling mechanism
EF is still reduced
what is decompensated heart failure?
SV begins to fall despite increased EDV
what is the sump-pump effect?
the ventricle pumps out less, so the feed pressure rises
what are the three etiologies of increased filling pressure?
sump-pump effect
sympathetic venoconstriction shifting blood centrally
increased salt and water retention
what is BNP?
it is a common marker for the diagnosis of heart failure
its secreted from the ventricular myocardium in response to volume expansion
at what BNP levels are heart failure unlikely, and likely?
unlikely at < 100 pg/ml
likely at > 300 pg/ml
what are some causes of false positives on a BNP test?
pulmonary HTN
pulmonary embolism
hyperthyroidism
renal failure
what is the earliest symptom of LV dysfunction?
dyspnea on exertion
what abnormalities would be seen on a physical exam for a patient with compensated heart failure?
nothing
what abnormalities would be seen on a physical exam for a patient with decompensated heart failure?
pulmonary rales
JVD
pulmonary edema
ascites and hepatomegaly
what is systolic heart failure?
an abnormality of ventricular emptying due to lack of contractility or increased afterload
what is diastolic heart failure?
impaired filling of the ventricle due to an abnormality of diastolic relaxation
what leads to eccentric hypertrophy?
volume overload
what leads to concentric hypertrophy?
pressure overload
what are three signs of left-sided heart failure?
dyspnea
orthopnea
fatigue
what are two signs of right-sided heart failure?
peripheral edema
right upper quadrant pain due to hepatic enlargement
what are three ways to decrease cardiac work, thus decreasing O2 demand?
rest
reduction of arterial pressure with vasodilators
reduction of filling pressure with venodilators
what drugs are used to prevent arrhythmias in patients with heart failure?
beta blockers
what are four drugs that can be used to improve inotropy?
digoxin
milrinone
dobutamine
dopamine
