Norton - HF Flashcards
Obstruction of flow leads to increase in _____
afterload
regurgitant flow leads to increase in
preload
Frank starling mechanism
increased preload causes dilation and increased contractility
Neurohumoral system activation as part of heart compensation
NE
RAA system
ANP
What precedes heart failure?
Hypertrophy
Causes for cardiac hypertrophy
increased mechanical workload
Trophic signals
How does hypertrophy occur
protein synthesis is stimulated – more sarcomeres
What are two patterns of hypertrophy
Concentric - pressure overload
Volume overload
Increased cavity diameter is seen in
Volume overload hypertrophy
New sarcomeres in concentric vs volume hypertrophy
Concentric - parallel
Volume - in series with existing
In volume overload, wall thickness is ____ whereas in in concentric, it is ______
Volume - varies
Concentric - increased thickness
_______ hypertrophy is risk factor for sudden death
LV
What is a key issue with cardiac hypertrophy
No inc in # of capillary with increased size of myocytes. BUT they require more oxygen/nutrients (Mitochondria)
S wave in LVH
greater than 30 mm in V2 and V3
physiologic hypertrophy is different in that capillaries
increase in density
what type of hypertrophy does aerobic exercise cause
Volume-load type
what type of hypertrophy does static exercise cause
Pressure type
cause for concentric hypertrophy
hypertension
aortic stenosis
cause for volume hypertrophy
mitral or aortic valve regurgitation
Changes occur _____ to heart
distant
forward failure
poor perfusion
backward failure
pulmonary, peripheral edema
CV system is a ____ circuit
closed
hence L-sided failure – > R-sided failure
Most patients present with clinical syndromes of _____
both R-sided/L-sided HF
Causes - L-sided HF
IHD
Htn
Aortic/mitral valvular disease
Nonischemic myocardial dz
Result of L-sided HF
congestion w/in pulm circ
dec periph BF
CHF is most often due to
Systolic dysfunction (contractile)
Systolic dysfunction
insufficient CO, dec EF
what other cardiac dysf show systolic dysf
IHD
Htn
Dilated cardiomyopathy
Diastolic dysf
failure to relax, expand, fill
dec SV, can’t respond to increased demand
what other cardiac issues show diastolic dysf
Massive LVH
myocardial fibrosis
Constrictive pericarditis
most common cause for R-sided HF
Left-sided HF
Cor pulmonale
pure right-sided failure
Due to parenchymal dz of lungs OR disorder of pulm vasculature
Disorders of pulmonary vasculature
Primary pulm htn, recurrent pulm embolus, dz causing hypoxia (Obs sleep apnea, altitude sickness)
