Heart Failure Flashcards
Heart failure
inability of the heart to pump blood at the required rates for normal metabolic activity
inability of the heart to only pump bloods at an elevated filling pressure
Mechanisms of cardiac dysfunction
Pump failure obstruction to flow regurgitant flow conduction defects compromised ventricular filling obligatory high output states Loss of continuation of the circulatory system Any severe cardiac disease
Pump failure
damaged muscle (IHD)
Intrinsic contractile failure is ( dilated cardiomyopathy)
Obstruction to flow
Overwork of the chamber proximal to the obstruction ( HPT, Aortic mitral stenosis ..)
Regurgitant flow
Volume overload (mitral and aortic incompetence)
Conduction defects
Uncoordinated generation or blockage of cardiac impulses
non-uniform and inefficient contraction of the myocardium ( heart block, v. Fibrillation)
Obligatory high output states
Increased work of the heart ( anemia…)
Loss of continuation of the circulatory system
Allows escape of blood (rupture of myocardium aneurysm)
Factors affecting features of cardiac failure
Age
Speed of onset
presence of other systemic disease
Types of cardiac failure
Acute failure chronic failure low output failure High output failure forwards failure backward failure systolic failure Diastolic failure
Acute failure
Due to sudden loss of contractility ( MI) or sudden overload (regurgitation due to valve rupture )
Chronic failure
Over a period of years (HPT..)
After an episode of acute failure
Low output failure
failure of the heart to pump normally
Cardiac output fails to increase or decline during exercise , or decline during rest
High output failure
Cardiac failure even if cardiac output is normal or elevated
Due to either blood volume increase, increased venous return , decreased peripheral resistance
come with tachycardia and Gallop rhythm
Forward failure
Diminished CO