What is systolic heart failure?
The inability of the heart to eject blood --> low blood pressure, exercise intolerance, weakness (cardiogenic shock)
What is diastolic heart failure?
Inadequate ventricular filling -->venous congestion, pulmonary edema (congestive heart failure)
What are examples of causes of pressure overload?
left --> aortic stenosis, systemic hypertension
right --> heartworm, pulmonic stenosis, pulmonary hypertension
What changes occur to the heart from pressure overload?
What are examples of causes of volume overload?
valvular insufficiency, PDA, ASD, VSD
What changes occur to the heart from volume overload?
What are the compensation mechanisms of the heart?
Increased cardiac output (hypertrophy, frank-starling), volume loss (ANP, BNP), volume gain (ADH, RAAS), vasoconstriction (symp. stim, RAAS, ADH), neurohormonal compensation
What are the negative effects of NE on the heart?
induce apoptosis, myocyte hypertrophy, Ca overload, decreased Beta 1 receptors, arterial baroreceptors less sensitive to stretch
What are the negative effects of angiotensin II on the heart?
chronic exposure: eccentric ventricular hypertrophy, induce inflammation and myocardial necrosis
What are negative effects of aldosterone on heart?
baroreceptor dysfunction, coronary inflammation, cardiac hypertrophy, cardiac fibrosis
What does RAAS do to bradykinin?
Causes it to be broken down by ACE to inactive peptide
What is the effect of TNF alpha (inflammatory mediator) on the heart?
decreased contraction, ventricular hypertrophy, apoptosis
What is the effect of nuclear factor Kappa B?
activation of inflammatory cytokines, myocardial hypertrophy
What can cause oxidative stress?
low levels of vitamin E
What is effect of ANP/BNP?
decrease free water absorption by decreasing sodium uptake at the CD, increase GFR, inhibit renin and aldosterone, increased levels correlate with poor prognosis in heart disease
What are clinical signs of right sided diastolic heart failure?
organomegaly, pleural effusion, distended vessels
What are clinical signs of left sided diastolic heart failure?
pulmonary edema, pleural effusion
What are clinical signs of systolic heart failure?
similar to other forms of shock
What is the danger of using positive inotropes in cardiogenic shock?
Can overload the heart
what are drugs used for in cardiogenic shock?
Maintain blood pressure and blood flow, and reduce congestion
Should fluids be given in cases of cardiogenic shock?
No; contraindicated due to fluid overload