Final Exam Flashcards
Acute Coronary Syndrome
sudden cardiac disorder which is irreversible
varies from angina, unstable angina, myocardial infarction
Acute Myocardial Infarction
acute obstruction of blood circulation (ischemia) to a region of the heart muscle, resulting in myocardial injury and necrosis (>1 cm)
this results in shortage of oxygen required for cell metabolism
ischemia
most common cause of AMI
atherosclerosis
- plaque develops in the wall of the artery
- plaque builds up
- plaque ruptures
- clot forms around rupture = blocking blood flow =lack of O2 and nutrients to myocardium = cell death
Troponin T
binds to tropomyosin and thin filament anchor of troponin complex
- found in cardiac muscle and regenerating skeletal muscle
Troponin C
binds Ca2+ to produce conformational change in troponin I subunit
- found in cardiac and striated skeletal muscle
Troponin I
binds to actin ONLY in cardiac muscle
- key regulator of cardiac muscle contraction/relaxation
actin
involved in muscle contraction
tropomyosin
regulate actin function
_____ & ______ are considered cardiac-specific targets in diagnostic tests for cardiac muscle damage
only cTn I and cTn T
- troponin I and T
when myocardial cells die, this is releaed
cardiac troponin cTn
depending on the type of MI, cTn levels reach their maximum between…
6 hours and 3 days and then start to decline
symptoms of AMI in men
- chest discomfort or pressure
- central chest pain -> arms, neck and/or jaw
- shortness of breath, coughing/wheezing
- unexplained fatigue, anxiety
- less common = light-headed/dizzy, nausea/vomiting, sweating
symptoms of AMI in women
more non-chest pain symptoms
- mild discomfort in chest/achy or heavy feeling in the chest
- upper body discomfort
- feeling of bad indigestion, nausea
- shortness of breath
- extreme fatigue, sweating
- light-headed/dizzy, fainting
roles of hs-cTn
- allows more rapid diagnosis and treatment of AMI
- potential use in assessing risk of CV events in the general population
- population reference ranges may allow differential diagnosis of AMI in biological males and females
CK-MB and MB (myoglobin)
- past cTnI and cTnT assays
- CK-MB = measurable for the same or later time than troponin; less sensitive (smaller elevation) than troponin N w/ 48 hr; not specific to cardiac damage
- MB = measurable for a much shorter period than troponin; less sensitive (much smaller elevation) than troponin; not specific to cardiac damage
symptoms of <3 failure
- difficult breathing
- dry, hacking cough
- swollen ankles, legs, abdomen
- rapid weight gain
- dizziness, fatigue, weakness
- decreased ability to exercise
- rapid or irregular heart beat
- increased need to urinate at night
- stomach bloating
- lack of appetite or nausea
what is <3 failure?
- heart is weakened/damaged and cannot pump blood effectively during increased activity or stress
reduces blood pressure and cardiac output
BNP (brain natriuretic peptide)
left ventricle wall stress
release of Pro-BNP and its de novo synthesis
where is NT-proBNP cleaved to its active form?
in peripheral circulation
what does BNP do?
interacts with natriuretic peptide receptor A
- natriuresis/diuresis
- peripheral vasodilation
- inhibition of RAAS
- inhibition of sympathetic nervous system
blood BNP correlates with…
severity of congestive heart failure
BNP can be elevated in other conditions (besides CHF)
- valvular heart disease
- atrial fibrillation
- myocarditis
- acute coronary syndrome
- cardiac surgery
- congenital heart disease
- advancing age
- pulmonary hypertension
- sleep apnea
- critical illness
- sepsis
- burns
- renal failure