28: Pathophysiology of heart failure/ Review Flashcards
Congestive heart failure
Increased venous and capillary pressures
Leads to congestion and edema
Pulmonary or systemic
Myocardial failure
reduced myocardial contractility
Pump failure
Right side vs. left side heart failure
Right: Ascites, pleural effusion, peripheral edema
Left: Pulmonary edema, pulmonary venous congestion
Backward Heart failure
Reduced filling leads to backup of blood
Forward heart failure
reduced output leads to poor perfusion
Cause of heart failure
insufficient cardiac output
Preload
Depends on venous return, blood volume and venous tone
Increase in diastolic volume
Increase in stroke volume
Increase in contraction is by what mechanisim
Frank-starling
Afterload
Resistance to ejection during systole
Reduces rate of ejection and stroke volume
Contractility
Ability of mycardium to generate force
Increase stroke volume
Depends on symp tone via B receptors
Frank-Starling mechanism
increased preload increases force of contraction and stroke volume to a point
Baroreceptor reflex
Decrease in CO = Decrease in BP
Cardiac B1 receptors
increase cardiac output
Systemic a1 receptors
vasoconstriction
Arteriolar constriction
Increased afterload
Decreased cardiac output
Venoconstriction
Increased preload
Venous congestion
Negative effects of B1 stimulation
arteriolar constriction
Venoconstriction
RAAS stimulation
Reduced renal profusion
Reduced sodium delivery
Sympathetic stimulation
Response to reduced tissue perfusion
Angiotensin 2 effects
Increased preload
Increased afterload
Water/Na retention
Vasoconstrictor
