Cardiomyopathy to valvular disease Flashcards
Cardiomyopathy is _____ (what kind of problem)
how is it divided
is a heart muscle disorder
there are primary and secondary forms
cardiomyopathy types
hypertrophic
dilated/congestive
restrictive
what is hypertrophic cardiomyopathy
what happens
primary or secondary
primary
excessive hypertrophy of ventricle
thick IV septum
etiology of hypertrophic cardiomyopathy
genetic (50% of cases) transmission is autosomal dominant
- idiopathic (50%)
- systolic fx is usually normal and therefore it can be asymptomatic (CO is normal)
from Fig 24-15 what can hypertrophic cardiomyopathy do to blood flow in heart
a thickened IV causes intermittent L ventricular outflow obstruction
mfts of hypertrophic cardiomyopathy
-dyspnea, angina, syncope (fainting d/t lack of blood flow to brain), palpitations
sudden death?
tx of hypertrophic cardiomyopathy
negative inotrope
(the IV is often so thck that drugs may not help. May use sx to thin IV septum)
a negative inotrope is a drug that dec myocardial activity eg beta blocker, calcium channel blocker)
Dilated/congestive cardiomyopathy
- cardiac enlargement especially ventricles
- weak contractions-> decreased ejection fraction (ejection fraction is expressed n percent and it describes the amount of the blood in the heart that is being pumped out with each beat?)
- alcohol abuse is implicated
restrictive cardiomyopathy
least common type
- very rigid V walls
- incomplete V filling-> dec CO
- usually leads to CHF
think its like the elastic band is now made of wire
electrical signal through heart
SA node->Av node->bundle of His->L and R bundle branches and L nterior fascicle for mitral
which part of heart is pacemaker
SA node
what type of cells are transmit the elctricity int he heart
specialized cardiac muscle cells
Arrythmias
- what are they
- what do they change/affect
- abnormal heart rate and or rhythm
- alters cardiac cycle (filling/emptying)
- CO and perfusion are affected
do arrythmias take place in diseased hearts only
no. can be in normal heart too
et of arrythmias
- heart defects (congenital)
- myocardial ischemia
- myocardial infarction
- drugs (particularly stimulants)
- fluid-electrolyte imbalances
atrial fibrillation vs flutter which is more problematic
what is worse than either of these
atrial fibrillation
worse=heart block
worst=ventricular fibrillation
atrial flutter
- regular, atrial tachycardia (~300BPM)
- regular, ventricular tachycardia (~150BPM)
- usually 2:1 ratio (A:V)
atrial fibrillation
- irreg, chaotic contractions (400-600BPM)
- irreg, rapid Ventricular rate (~80-180BPM it ould be the normal rate but will be irreg)
Heart block
(not the flow of blood)
-abnormal or no impulse conduction for atrium to ventricles
1st, 2nd, 3rd degree heart block
1st degree=delayed conduction, reg rhythms
2nd degree hert block=intermittent failure of conduction
3rd degree-no conduction, independent Atria rate & Ventricular rate (they are still contracting despite lack of rhythm)
Ventricular fibrillation
quivering, no contraction
can cause death in minutes
(neither filing nor empyting)
Tx of arrythmias
based on type
- drugs eg beta blockers and calcium channel blockers
- defibrillation-(apply electrical current to chest wall which terminates all electrical activity in heart then, stop shocking and wait for SA to resume pacemaking)
- pacemakers
- ablation (not always indicated
Valvular disease refers to which valves
the cardiac valves
valvular disease
what hapens and why?
(either the valve opens when it shouldnt or doesnt open adequately)
damaged valves->impeded flow or regurgitation
-aortic and mitral valves are more susceptible WHY?
(mitral valve must work hardest and L semilunar to push blood into systemic circuit.)
Et of valvular disease
- valve trauma
- degenerative change
- ischemic damage
- congenital defects
what is stenosis?
the abnormal narrowing of a passage in the body.
stenosis in r/t valvular disease
the valve will either have stenosis and be too narrow or it will be incompetent and not close well enough
- stenosis
- stiff valve, narrow orifice->impeded flow
incompetent valve
-distorted valves->improper closure->regurgitation
which valve is most commonly affected by stenosis or incompetence?
mitral
Tx of valvular disease
maintain/improve fx using drugs
-sx? (in many cases its nec. damaged valve is replaced)
how can hypertrophic cardiomyopathy be asymptomatic
systolic fx is usually normal
how are atrial flutter and fibrillation different other than the inc heart BPM
flutter has regular beat
