Chapter 10 Flashcards
acute myocarditis
Chronic, hypersensitivity myocarditis
Multinucleate giant cells
Atrial septal defect
L to R
Patent ductus arteriosus
L to R
Ventricular Septal Defect
42%
L to R
myxoma
rheumatic valvular disease
calcific aortic stenosis
scarlet fever
what are the two leading causes of death in the US?
- heart disease
- cancer
what’s the MC mechanism of heart disease?
contractile (pump) failure
Why, when a patient has heart failure/CHF, can they not meet tissue demands?
- decreased cardiac output (MC)
- increased tissue demands (hyperthyroidism, severe anemia, fistula – ‘high-output failure’)
what dysfunctions cause decreased cardiac output?
- systolic dysfunction: weak contraction
- Diastolic dysfunction: failure of relaxation/filling; females
- valvular dysfunction: stenosis, endocarditis
what are the risks for systolic dysfunction?
CAD, systemic HTN, decreased pH
what are the risks for diastolic dysfunction?
Females
myocardial fibrosis, amyloidosis, left-sided hypertrophy, pericardial tamponade
what is forward failure? backward failure? are they typically found together or separate? what organs do they affect?
forward: insufficient output = hypoxia
backward: venous congestion – increased venous volume/pressure
forward failure is almost always combined with backward failure – affects virtually every organ
what are 3 adaptations that occur with the heart?
- Frank-Starling mechanism
- Neurohumoral mechanisms
- Cardiac hypertorphy
what is the Frank-Starling mechanism?
increased ventricular stretch = stronger contraction
benefit: increased output
cost: increased O2 , increased tension
compensated heart failure
what are neurohumoral mechanisms of heart adapation?
NE: increased heart rate, increased contractility, R-A-A system (increase BP)
ANP: vasodilation (balances NE)
Why does cardiac hypertrophy occur?
when the heart gets overloaded.
can be physiological or pathological
increases O2 consumption
what are the symptoms of left sided heart failure? right sided?
left sided: short of breath, fatigue
right sided: edema in legs (pitting edema) and liver failure
what is the ‘good’ type of cardiac hypertrophy? the ‘bad’ type? How can you tell the difference?
good: eccentric hypertrophy
bad: concentric hypertrophy
can tell the difference by looking at the ratio of wall to chamber size
what causes left-sided heart failure?
IHD (CAD), HTN, valve disorders (mitral & aortic), primary myocardial disease
once the left ventricle hypertrophies, what else in the heart can dilate? which causes what?
the left atria– atria fibrillation atrial thrombi (stroke)
what are symptoms of left sided heart failure?
pulmonary edema
dyspnea
rales (cracking in lungs)
orthopnea (drowning when lying down)
cough
tachycardia
what is right sided heart failure most commonly caused by?
left sided heart failure
what is cor pulmonale?
only right sided heart failure
happens following pulmonary HTN
how common is congenital heart disease? what increases the risk?
30% of birth defects
prematurity increases risks
What opening is present at birth that connects the right and left atrium?
foramen ovale
what opening is present at birth that connects the left pulmonary artery and the aorta?
ductus arteriosus
What is known to cause congenital heart disease?
- genetic: trisomies (13, 18, 21), polygenic
- Environment: teratogens, maternal diabetes, infxn
- 90% are idiopathic–> septal defects make up over half of the cases, MC is ventricular septal defects
What happens with right-to-left shunts? what causes it?
blood bypasses the lungs
cyanosis
causes: tetralogy of Fallot (MC) & transposition of great arteries
What happens with left-to-right shunts? what are examples of them?
pulmonary HTN
caused by ASD, VSD & PDA
What are examples of obstruction of flow congenital heart disease?
valvular stenosis and aortic coarctation (narrowing)
Details about atrial septal defects
left-to-right shunt
MC asymptomatic until adulthood
rare spontaneous closure
10% of malformations
details about ventricular septal defects
MC structural abnormality – 42%
Left-to-right shunt
may spontaneously close
only 20-30% in isolation
Details about patent ductus arteriosus
left-to-right shunt
90% isolated
7% of malformations
What is the most common CHD to cause cyanosis?
Tetralogy of fallot –>bypasses the lungs
What defects cause Tetralogy of Fallot?
- Ventricular septal defects
- Right ventricular outflow obstruction (subpulmonic valve stenosis)
- Overriding aorta (over VSD) –> between ventricles, right ventricle to aorta (right to left shunt)
- right ventricular hypertrophy
What causes a ‘boot-shaped’ heart?
tetralogy of fallot
What changes occur with transposition of the great arteries?
arteries connect to wrong ventricles
right ventricle –> aorta
left ventricle –> pulmonary artery
Why is transposition of the great arteries so serious?
it separates pulmonary & systemic circulation
its incomplatible with postnatal life– sunts are required
Who is most likely to have aortic coarctation?
males
turner syndrome (45, X)
what defect to the aortic valve can occur with aortic coarctation?
>50% also have a bicuspid aortic valve
With infantile aortic coarctation, where does it occur? adult?
infantile: proximal to a PDA
adult: infolding near the ligamentum arteriosum, MC asymptomatic
features of aortic coarctation
upper extremity HTN
weak LE pulses
LE vascular claudication & cyanosis
systolic murmurs/thrills
with ischemic heart disease, what happens to the myocytes? how long until dysfunction? necrosis?
the cardiac myocytes use oxidative phosphorylation
dysfunction: 1-2 minutes
necrosis: 20-40 minutes
What disease makes up 90% of IHD? What else can cause IHD less commonly?
coronary artery disease – atheromas thromboemboli, vasospasm
also caused by increased tissue demand, decreased BV or hypoxia
What is the leading cause of death in the US, specifically?
Ischemic Heart Disease – CAD, pneumonia, CO poisoning, A-V fistula
What are cardiac syndromes the result of?
Myocardial ischemia
What are the forms of acute coronary syndrome?
angina pectoris– chest pain; ischemia but NO cellular death
acute myocardial infarction (M.I.)
Chronic IHD –> CHF
sudden cardiac death (SCD)
Angina pectoris means how much occlusion? Unstable angina?
Angina pectoris: >70% occluded –> critical stenosis
unstable angina: > or equal to 90% occluded
What is the process of ischemic heart disease?
- inflammation – atherosclerosis, abrupt plaque changes
- Thrombosis – associated with ACS, sudden coronary artery occlusion
- Vasoconstriction– decreased arterial lumen, may rupture plaques –>risks: increase SNS, inflammation, endothelial dysfunction
What do people describe as having ‘an elephant on their chest’?
angina pectoris
sub-sternal chest pain: crushing & squeezing
referred: jaw, left arm, back, shoulders
Stable vs. variant angina vs. Unstable
stable: aka typical, episodic, exertional, relieved by rest and vasodilators
variant: aka Prinzmetal, vasospasm at REST, responds to vasodilators
unstable: aka crescendo/pre-infarction angina, increased frequency, intensity and duration; provoked by **decreased exertion, **90% occlusion
cause of unstable angina
plaque disruption
thrombosis
embolization
vasospasm
Angina pectoris in females
may have NO angina
dyspnea, unexplained fatigue
lower chest discomfort/pressure
back pain
nausea, dizziness
may mistake for an upset somach
what’s another name for heart attack?
myocardial infarction
what is the mc cause of MI?
90% cause by acute coronary artery thrombosis
pre-existing atheroma: rupture –> vasospasm & coagulation –> rapid/severe obstruction
T/F: Myocardial infarctions cause rapid death and loss of contractility
F: MI cause rapid DYSFUNCTION and loss of contractility
what are the risks for MI?
males
PM females
age
HTN
smoking
diabetes
sickle cell disease
amyloidosis
CHF (stasis)
What is the most common cause of sudden cardiac death?
Ventricular fibrillation (80-90%)
T/F: MI can cause arrhythmias
T: it can lead to coronary artery ischemia and cause electrical instability which can lead to ventricular fibrillation
Reperfusion with myocardial infarction: how is it done? what does it cause?
Artifically done by thrombolytic meds, angioplasty and bypass
causes ROS, hemorrhage and endothelial swelling –> blocks capillaries, temporarily ‘stunned’ myocardium
may need temporary pump assistance
What is special about the angina associated with Myocardial Infarction?
Unrelieved by nitroglycerine
How are Myocardial infarctions diagnosed in the laboratory?
CK-MB and troponins
after a myocardial infarction, what happens to the viable myocarium left? to the functioning of the heart?
it is overloaded
hypertrophy and dilation occurs which leads to failure
walls may rupture
contractile dysfunction – arrhythmia, CHF, cardiogenic shock
general pericarditis
prognosis of M.I.
poor
2nd MI
arrhythmia (SCD)
CHF
What is sudden cardiac death?
sustained arrhythmia
lethal arrhythmia: MC involves left ventricle
sudden unexpected death
no symptoms in previous 24 hours
typically caused by Ventricular fibrillation (MC) or asystole
Commotio cordis
blow to sternal region disrupts heart rhythm
Adolescent males: avg 15 years
What happens to the heart with hypertensive heart disease?
the heart hypertrophies to meet increased cardiac demands, the ventricles dilate
metabolic demand increases with no increase in blood supply to compensate
cardiac decompensation (CHF) –> eventual loss of contractility
systemic hypertensive heart disease causes what other heart disease?
left sided heart disease, left ventricular hypertrophy
what can help decrease the risks of systemic hypertensive heart disease?
blood pressure management– hypertrophy is reversible
how does pulmonary hypertension affect the heart?
causes right sided heart failure – cor pulmonale
right ventricle hypertrophy and early dilation
what can cause pulmonary hypertensive heart disease?
pulmonary fibrosis
cystic fibrosis
PE
kyphoscoliosis
what causes acute pulmonary hypertensive heart disease?
what causes chronic pulmonary hypertensive heart disease?
acute: large pulmonary embolism; >50% occlusion
chronic: prolonged COPD or pulmonary fibrosis, right sided hypertrophy
what are 2 types of valvular heart disease?
- stenosis
- insufficiency
What causes stenosis? what is MC affected?
calcification and scarring
chronic
mitral valve is MC
What causes insufficiency?
valvular destruction
abnormal suportive structures
What is a murmur?
turbulent flow through diseased valve
Thrill: turbulence –> palpable vibration
what is the MC cause of aortic valve stenosis?
calcific aortic stenosis
what population does calcific aortic stenosis commonly occur in? what accelerates it? what condition changes the age group?
older adults –> 60-80 years old because of wear and tear
accelerated by HTN and inflammation
having a bicuspid aortic valve makes it occur earlier– 40-50 years
rheumatic valvular disease is caused by what? when does it occur (time period)?
group A beta-hemolytic streptococcal pharyngitis
occurs 2-3 weeks post infection
what is the most common sign in children with rheumatic valvular disease?
what is the most common sign in adults with rheumatic valvular disease?
what’s a general symptom of rheumatic valvular disease?
carditis
migratory polyarthritis
Sydenham’s chorea
when is rheumatic valvular disease most commonly diagnosed?
between 5-15 years old
What is the only acquired cause of mitral stenosis?
Rheumatic valvular disease
What is pancarditis?
rheumatic heart disease
what are aschoff bodies? where are they most commonly found?
nodules around the heart valve
found with acute pancarditis
MC found in the mitral valve
what changes, of the heart specifically, occur with rheumatic valvular disease?
aschoff bodies (acute)
fibrosis (chronic)
fibrinoid necrosis of valve(s)
possible arrhythmias
what causes scarlet fever? what is it a rxn to? where does the infxn occur?
Group A beta-hemolytic strep
it’s a rxn to erythrogenic toxins
infection is pharyngeal and cutaneous
1-4 days
What is the hallmark of scarlet fever?
pink punctate skin rash
circumoral pallor rash on face
strawberry tongue
What condition can scarlet fever transition into?
rheumatic fever
infective endocarditis causes what?
infection of hear chambers or valves
bacteremia (MC)
what are the symptoms of infective endocarditis?
flu-like symptoms: pyrexia, chills, fatigue, weight loss, murmur
or lethal: arrhythmia or renal failure
which is easier to treat: acute or subacute infective endocarditis? why?
subacute has low virulence and is easier to treat –> present in previously abnormal tissue
acute is destructive, virulent and difficult to treat –>present in previously normal valve
why are prosthetic cardiac valves used?
used as an intervention for valve disease
types:
- Mechanical (MC) –anti-coagulative
- Bioprosthetic– not anti-coagulative
cardiomyopathy are mostly caused by:
they’re idiopathic, with genetic risks
what is the most common type of cardiomyopathy? least common type?
MC: Dilated
LC: restrictive
What physiologically happens with dilated cardiomyopathy?
- progressive dilation of all chambers
- systolic dysfunction: dyspnea, fatigue
What condition mimics progressive CHF?
what are the risks for the answer above?
age group?
dilated cardiomyopathy
risks: genetics, viral infections, alcohol
20-50 years old
What conditions can occur with dilated cardiomyopathy?
- mitral regurgitation
- Arrhythmia
- Thromboemboli
Which cardiomyopathy is genetic?
Hypertrophic cardiomyopathy, beta-myosin mutation
What are the signs of hypertrophic cardiomyopathy?
- Hyper-contractile sarcomeres
- Massive Left ventricular hypertrophy
- Diastolic dysfunction
- decreased stroke volume/CO
What condition has asymmetrical septal hypertrophy?
hypertrophic cardiomyopathy
ventricular septum > ventricular wall
With hypertrophic cardiomyopathy, what does the heart ventricle look like?
When does it typically occur?
elongated –> ‘banana like’
after puberty–> growth spurt
What causes 1/3 of SCD among younger athletes?
Hypertrophic cardiomyopathy –> V-fib
What are the symptoms of restrictive cardiomyopathy?
interstitial fibrosis: stiff myocardium
dyastolic dysfunction = decreased filling
45-90% ejection fraction
What can cause restrictive cardiomyopathy? who’s at most risk for each cause?
- Amyloidosis: senile cardiac amyloidosis –>african americans
- Endomyocardial fibrosis: fibrosis of the ventricular endocardium, pediatrics/young adults in Africa
- Etc: irradiation, idiopathic
What is the MC cause of myocarditis in the USA?
viral infection: coxsackievirus A & B, HIV, CMV and influenza
What very serious condition does myocarditis cause?
arrhythmia/SCD
Histology wise, what is the difference between acute and chronic/hypersensitivity myocarditis?
Chronic/Hypersensitivity myocarditis has multinucleate giant cells
Which is more common, acute or chronic/hypersensitivity myocarditis?
Acute
What is pericarditis? What causes primary pericarditis? Secondary?
pericarditis is pericardial inflammation
Primary: infection – viral (MC), bacterial, fungal
Secondary: MI, surgery, irradiation, rheumatic fever, SLE, CA
what can severe pericarditis cause? What causes constrictive pericarditis?
cardiac tamponade- pericardial compression (decreased filling)
fibrosis causes constrictive pericarditis
What type of inflammation occurs with pericarditis? what does that mean?
Fibrinous inflammation– severe increased permeability allows fibrin out of circulation
T/F: MC metastasis to the heart is the MC cardiac neoplasm
True
Cancer from where most commonly mets to heart?
Lung
most common primary cardiac neoplasm?
Myxoma
primary cardiac neoplasm of children
rhabdomyomas
what is the MC primary malignant cardiac tumor?
Angiosarcoma
where are Myxomas MC found?
what valve does it MC interfere with?
MC found on/near fossa ovalis (left atrium)
‘wrecking ball’ that interferes with MITRAL valve
What is the MC long-term limitation of cardiac transplantation?
Allograft arteriopathy– silent MI
