Acquired Heart Diseases Flashcards
(49 cards)
what is MMVD
degeneration and thickening of the mitral valve leading to incompetency (regurgitation), left atrial enlargement, volume overload, and CHF
is pulmonary venous hypertension the same as pulmonary hypertension (arterial)
NO - venous hypertension should resolve when L-CHF is treated
can become clinically significant and require treatment
what factor determines if MMVD patients require treatment
LA enlargement
what are common outcomes of MMVD
- L-CHF (possibly biventricular)
- pulmonary hypertension
- LA rupture
- atrial fibrillation
pimobendan
inodilator - positive inotrope + peripheral vasodilation
increases inotropy by increasing Ca sensitivity in cardiomyocytes NOT increasing overall amount of Ca
enalapril/benazepril
ACE inhibitors
inhibits RAAS activation to slow volume overload to the left heart
furosemide
diuretic
promotes excretion of excess fluid volume (pulmonary edema)
spironolactone
aldosterone inhibitor
inhibits RAAS activation to slow volume overload
sildenafil
PDE inhibitor
dilates pulmonary vasculature to reduce pulmonary hypertension
RARELY used for MMVD - venous hypertension often resolves with CHF management
risky bc dilation of pulmonary vessels will increase volume to L heart
MMVD prognosis
~15 mo from stage B2 to development of CHF
~12 months after onset of CHF
what is dilated cardiomyopathy
heart muscle disease with characteristic ventricular dilation leading to systolic dysfunction
primarily affects the LV
pathology of DCM
severe dilation of LV + LA +/- RV
myofiber degeneration and necrosis with minimal to no inflammation
is the mitral valve abnormal in DCM
NO - normal mitral valve at the start of disease, stretch from LV dilation causes regurgitation
how is the occult phase of DCM diagnosed
occult phase is often long and difficult to diagnose
requires Holter monitoring, NT-proBNP, C-TNI, or PDK4 genetic testing
outcomes of DCM
- exercise intolerance
- syncope
- L-CHF (cough, resp effort)
- sudden death
is the murmur from MMVD or DCM louder
MMVD
DCM is quieter because it is not a primary mitral valve problem
prognosis of DCM
occult: months to years with pimobendan
DCM w/ CHF: 9-12 months with treatment
what is canine ARVC
heart muscle disease with characteristic right ventricular tachyarrhythmias + fibro-fatty infiltration of the right ventricle (+ left if progressed)
leads to syncope and death
what does incomplete penetrance of the mutation mean
not all boxers with the mutation are affected with clinical ARVC
what does variable expressivity of the mutation mean
boxers with the mutation are affected with variable severity
homozygous: earlier onset, accelerated disease course, increased risk of sudden death
outcomes of ARVC
- RV arrhythmias
- collapse or syncope
- sudden death
what are the three forms of ARVC
- asymptomatic
- collapse and syncope
- structural changes
asymptomatic ARVC
no clinical signs but meets diagnostic criteria on holter monitor
collapse/syncope ARVC
clinical signs + meets diagnostic criteria on holter monitor
