congestive heart failure pathophysiology

pathophysiology of congestive heart failure

1. Depressed ejection
fraction (<40%)
-coronary heart dse
-hypertention
-chronic volume
overload.
Pulmonary heart
disease
-cor pulmonale
-pulmonary vascular dis
Ant-lat portion of upper medula
Vasoconstriction of blood vessels
Converts angiotensinogen to angiotensin I
Preserved ejection fraction
(>40-50%)
-aging
-pathologic hypertrophy
-restrictive cardiomyopathy
-fibrosis
High-output states
-thyrotoxicosis
-beri-beri
-chronic anemia
-systemic arteriovenous
Injury to the heart muscle
Loss of function of cardiac myocytes
Dec. ability of the myocardium to Generate force
Dec cardiac contractility
Dec SV
Dec CO (s/sx: dec exercise tolerance)
“Unloading” of high pressure baroreceptors in carotid sinus & aortic arch
Efferent sympathetic nervous system
Renal hypoperfusion
Release of rennin
ACE converts angiotensin I to angiotensin II
Stimulate cardiac regulatory center in the pons & medulla
arginine vasopressin (ADH) from posterior pituitary
Vasoconstriction
Inc the permeability of the renal collecting ducts
Vasoconstriction of the peripheral vasculature

2. Reabsorbtion of water& electrolyte
aldosterone
Inc cardiac output
(via compensation)
Inc force of contractility
Inc preload (20-
25mmHg)
Remodeling of LV
Inc heart rate
s/sx: tachycardia
Transcriptional and
posttranscriptional changes in the
genes and proteins
Excessive beta activation
Leakage of Ca
Inc in pulmonary
capillary pressure
Pulmonary
congestion
(s/sx: DOB)
Stiffning of the
ventricles
(s/sx:
arrhythmias)
Dec diastolic filling
Inc wall stress of LV
LV wall thining
From prolate
ellipsoid to
spherical shape
Papillary msc r
pulled apart
Further dec SV
Incomp of
mitral valve
Afterload mismatch
Mitral
regurgitation
Dec CO
Inc afterload,
HEART FAILURE
LV End
systolic vol inc
dyspnea
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