Card Set Information
common sequelae of cardiac disease
What is heart failure? Whats the results?
inability of heart to maintain sufficient cardiac output to meet metabolic demands of tissues and organs
-results in congestion of blood flow in systemic/pulmonary venous circulation, inability to ^ cardiac output to meet the demands of activity or ^ tissue metabolism
-common in >65 yrs old
What is the etiology and pathogenesis of HF?
potential consequence of most cardiac disorders
: myocardial ischemia, followed by hypertension and dilated cardiomyopathy
-results from impaired ability of myocardial fibers to contract, relax, or both
What is systolic dysfunction?
: MI - Myocardial infarction
-reduced contractility evidenced by low ejection fraction and reduced inotropy (decreased sympathetic 'tone') during ventricular systole
-impaired contractility involves loss of cardiac muscle cells, β-receptor down regulation, and reduced ATP production
What is diastolic dysfunction?
ischemic heart disease and hypertension - main causes
-disorder of myocardial relaxation such that ventricle is excessively noncompliant and does not fill effectively
-low cardiac output, congestion, edema formation with normal ejection fraction
What are the compensatory responses that are currently being reduced to management of HF
What is SNS activation?
primarily a result of baroreceptor reflex stimulation
-CNS ^ activity in sympathetic nerves to the heart resulting in venoconstriction
-juxtaglomerular cells release renin, activating RAAS cascade, resulting in ^ sodium and water retention
What does an increased preload mean?
initially a consequence of reduced Ejection Fraction (EF) with resultant ^ in resident end-systolic volume (ESV)
-decreased CO to kidney reduces glomerular filtration =fluid conservation
-RAAS cascade activated = elevated blood vol.
What is myocardial hypertrophy; what remodels it?
results from chronic elevation of myocardial wall tension (law of Laplace)
-high systolic pressure in ventricle needed to overcome a high afterload leading to hypertrophy
-neurohormonal factors have hypertrophic effect on heart
-angiotensin II involved in remodeling
What are the clinical manifestations of HF?
L ventricular failure - most common
-often leads to R ventricular failure
What is forward failure?
insufficient cardiac pumping manifested by poor CO
What is backward failure
congestion of blood behind the pumping chamber
What is L sided HF associated with?
: results in accumulation of blood within pulmonary circulation, pulmonary congestion, and edema
: results in insufficient CO with diminished delivery of oxygen and nutrients to peripheral tissues and organs
What is R-sided HF
pulmonary disorders - ^ pulmonary vascular resistance - high afterload - R ventricular hypertrophy - R ventricular failure
-backward effects due to congestion in the systemic venous system
-forward effects cause low output to L ventricle leading to low CO
What are the backward effects of L sided HF?
dyspnea on exertion
paroxygsmal nocturnal dyspnea
What are the forward effects of L sided HF
^ heart rate
What are the forward effects of R sided HF
^ heart rate
What are the backward effects of R-sided HF
jugular vein distention
What is a biventricular HF
result of primary L sided HF progressing to R sided HF
-pulmonary congestion due to L sided HF
-systemic venous congestion due to R sided HF
What are the class and stage of HF? how is it assess?
hortness of breath
-assess by xray and echocardiography
B type natriuretic peptide lvl
-severity of symptoms used to ID class/stage of HF
treatment of HF
improve CO while minimize congestive symptoms and cardiac workload
-by manipulating preload, afterload, and contractility