ACUTE CORONARY SYNDROME Flashcards
Coronary artery disease is that in which ________ builds up inside the coronary arteries and restricts the flow of blood (and therefore _____________ ) to the heart
atherosclerotic plaque
the delivery of oxygen
Coronary artery disease can lead to acute coronary syndrome (ACS), which describes any condition characterized by signs and symptoms of ________—a sudden ________________
sudden myocardial ischemia
reduction in blood flow to the heart.
Acute coronary syndrome
• The signs and symptoms of ACS constitute a continuum of intensity from ________ to _________ to ______.
unstable angina
non–STsegment elevation MI (NSTEMI)
ST- segment elevation MI (STEMI)
stable angina and myocardial infarction (MI) both come under the ACS umbrella.
T/F
F
Unstable angina**
Unstable angina and NSTEMI normally result from a _________________________, whereas STEMI results from a _________________________,
partially or intermittently occluded coronary artery
fully occluded coronary artery.
ACS begins when a ______ —————— in a coronary artery stimulates _______ and _________ .
It’s the _______ occluding the vessel that prevents myocardial perfusion
disrupted
atherosclerotic plaque
platelet aggregation and thrombus formation
thrombus
Most cases of infarction are due to the formation of ____________ on the surface of the plaque.
an occluding thrombus
Infarction pathogenesis
Reduced blood supply causes less _____ production, leading to failure of the ______ and _____ and an accumulation of _____ and _____ , resulting in (acidosis or alkalosis?) .
At this point, __________—will occur unless interventions are begun that limit or reverse the ischemia and injury.
ATP
sodium– potassium and calcium pumps
hydrogen ions and lactate; acidosis
infarction— cell death
During the ischemic phase, cells exhibit __________________ metabolism. If myocardial perfusion continues to decrease, ____ metabolism ______ and eventually _______ metabolism will be significantly _______. This period is known as the _____ phase. If perfusion is not restored within about ______], myocardial ______ results and the damage is _______.
both aerobic and anaerobic
aerobic ; ceases
anaerobic; reduced
injury; 20 minutes
necrosis; irreversible
Impaired _______ , is the result of scar tissue replacing healthy tissue in the damaged area, decreases cardiac output, limiting perfusion to vital organs and peripheral tissue and ultimately contributing to signs and symptoms of _____.
myocardial contractility
shock
Clinical manifestations of ACS include changes in level of ______; _____ ;________ skin; ___tension; _____cardia; and ___eased urine output.
consciousness
cyanosis; cool, clammy
hypo; tachy; decr
SIGNS AND SYMPTOMS
•______ or ______ , continues to be recognized as the classic symptom of ACS.
Angina, or chest pain
In unstable angina, chest pain normally occurs either at ____ or with _____ and results in limited activity.
Chest pain associated with NSTEMI is normally (shorter or longer?) in duration and (less or more?) severe than chest pain associated with unstable angina.
In both conditions, the ______ and ____ can increase if not resolved with ____,_______, or both and may last longer than ________
rest; exertion
Longer; more
frequency and intensity of pain
rest, nitroglycerin
15 minutes.
SIGNS AND SYMPTOMS
• Pain may occur with or without radiation to the ____,_____,____, or _____ area.
•In addition to angina, patients with ACS also present with ___,_______,———- .
•Changes in vital signs, such as _________,_____,_______,_______ , and decreased _________ or cardiac rhythm abnormalities may also be present.
arm, neck, back, or epigastric
shortness of breath, nausea, and lightheadedness
tachycardia, tachypnea, hypertension, or hypotension
oxygen saturation (SaO2)
DIAGNOSING ACS
• The utility of various biomarkers is determined by the _______ and ______ as well as by the extent of their _________
timing and duration of their elevation
cardiac specificity
_____________ are the preferred biomarkers for diagnosing acute MI
With reason
Cardiac troponins
because elevated levels correlate with a more accurate diagnosis, predict a high risk of future cardiac events.
Cardiac troponins
• Levels of troponins ___ and —- increase within ___________ of myocardial injury
I and T
four to six hours
Cardiac troponins :
•troponin I levels remain elevated for ___-_____ , and troponin T levels remain elevated for ____-____.
four to seven days
10 to 14 days
Normal reference ranges for cardiac biomarkers vary among laboratories; in order to diagnose myocardial necrosis a ______ troponin elevation greater than the ______ percentile of an agreed-upon reference control group is required.
Single
99th
CK-MB is a cardiac-(specific or non specific?) enzyme that’s released within _________ of injury and remains elevated for _________ after injury.
Specific
four to six hours
48 to 72 hours
__________ levels of CK-MB greater than the 99th percentile of a reference control group contribute to the diagnosis of acute MI
Two consecutive
Myoglobin, a ____ protein, is cardiac (specific or non-specific?)
heme
Non specific
Myoglobin, is still considered a valuable myocardial infarction biomarker
Why ?
because it’s the first to rise after myocardial damage.
If a patient presents with ACS symptoms that started less than ______ earlier, _______ and _____ levels may not yet be elevated. In such a case, ______ can rule out or lead to an early diagnosis of acute MI and prompt decisive therapy.
3 hours
CK-MB and troponin
myoglobin
Electrocardiographic findings.
A ___-lead electrocardiogram (ECG) should be performed in patients with symptoms consistent with ACS and interpreted by an experienced physician within _________of ED arrival.
12; 10minutes
Electrocardiographic findings.
Findings on a 12- lead ECG help the practitioner to differentiate between myocardial ______,______, and ——— ; _____ the affected area; and assess related __________.
ischemia, injury, and infarction
locate
conduction abnormalities
Electrocardiographic findings.
Electrocardiographic findings reflective of unstable angina or NSTEMI include ST-segment ———- and ______ T waves.
_______ will normally resolve when the ischemia or pain has resolved, although ___________ may persist. Providers should review electrocardiographic findings as well as levels of cardiac biomarkers
depression; inverted
ST depression; T-wave inversion
Management of ACS
_______,_______,_______ and _______
Aspirin,oxygen,nitroglycerin,andmorphine sulfate
Management of ACS
ASPIRIN
• Aspirin inhibits _______ and vaso_____.
Aspirin is contraindicated in patients with active _____ disease, _____ disorders, and an allergy to aspirin.
platelet aggregation
constriction
peptic ulcer; bleeding
Management of ACS
Supplemental oxygen will decrease the ____ associated with myocardial ______.
pain
ischemia
Management of ACS
Nitroglycerin causes venous and arterial _______, which (reduces or increases?) both _______ and ______ and ultimately decreases myocardial ___________.
dilation
Reduces
preload and afterload
oxygen demand
Management of ACS
Morphine causes ______ and _____ vaso_______, reducing both preload and afterload, and the drug’s ____ properties decrease the _____ and _____ associated with ACS. However, morphine can cause ___tension and respiratory ______.
venous and arteriolar
dilation; analgesic
pain and anxiety
hypo; depression
Adjunct drug therapy
•_________
• Clopidogrel–prevents _______
• ACE inhibitors - decrease the risks of ___________ and death in ACS patients and should be administered within ______ and _____ upon discharge
Beta blockers
platelet aggregation
leftventricular dysfunction
24 hours ; continued
Reperfusion therapy is recommended in patients diagnosed with _____. Reperfusion strategies include a variety of PCIs ( _______________ ) and ______ drug therapy. The goal of reperfusion therapy is to restore blood flow to ischemic myocardial tissue and prevent further complications. Reperfusion therapy should be initiated within a _______ to improve patient outcomes
STEMI
percutaneous coronary intervention
fibrinolytic
defined time frame
Fibrinolytic therapy refers to the administration of “ __________” drugs, which ______ existing ______ by converting _________ to _____ and degrading fibrin clots.
clot-busting
dissolve
thrombi
plasminogen to plasmin
In fibrinolytic therapy
The drugs most commonly used are _____ (recombinant tissue–type plasminogen activator [rt-PA]; ———-), ______ (_____), and _____ (_____). Fibrinolytic therapy is most effective when given within ________ after symptom onset
alteplase; activase
Reteplase; retavase
Tenecteplase; TNKase
three hours
Summary of pattern of release of biomarkers with time
_____-______-_________-________
Myoglobin- LDH- CKMB- cardiac troponin
Summary of pattern of release of biomarkers with time
• MYOGLOBIN-
The detectable levels of myoglobin in the blood are found as early as ______ after the onset. Its peak value is obtained at _______ after the onset of the symptoms and then it normalizes over the next 24 hours.
2 to 3 hours
6 – 12 hours
LDH - ___ease in serum LDH activity is found following myocardial infarction beginning within ____ hours and reaching a maximum at about _____ hours and it remains elevated for ___days before coming down to normal levels.
Incr
6 – 12
48
4-14
LDH has _____ isoenzymes (LD__—__).
5
1-5
The cardiac muscles are rich in LD__ and LD_ (LD_>LD_) while in liver LD__, LD__ and LD__ being plentiful.
The differential distribution of LD isoenzymes makes its use in differential diagnosis as a marked increase in the proportion of LD1 in the serum in ___ and LD5 in ___ disease.
1; 2
1;2
3;4;5
MI; liver
CREATINE KINASE (CK) AND ITS ISOENZYME MB (CKMB)
- Serum CK activity increases following MI beginning within _____ and peaking on an average at ____ and returning to normal within ______.
However, its presence in large amounts in _____ muscle and increased levels found in _____,_______,_______ , cerebrovascular accidents and a variety of myopathies make it (suitable or unsuitable?) as a marker of myocardial injury.
6 hours ; 24 hours
2-3 days
skeletal; muscular dystrophy, hypothyroidism , hypothermia , alcoholism
Unsuitable
CK has three isoenzymes namely CK___, CK ___ and CK__ each consisting of two subunits named according to main tissue of occurrence: B (___) and M(_______).
BB; MB; MM
brain; skeletal muscles
Myocardium contains ___% CKMB and __% CKMM along with traces of mitochondrial CK (macro CK type II) while skeletal muscles contain about ___% CKMM, ___% CKMB and traces of CKBB and mitochondrial macro type II. Being highest in proportion in myocardium _____ has been used as the biochemical marker in patients with suspected acute myocardial infarction (AMI).
40;60
97; 2-3
CKMB
cTroponin T and I - TnT and TnI are being used as the biochemical markers for the diagnosis of myocardial injury. The troponins found in cardiac tissue (cTn) have (a different or the same?) amino acid sequence than that present in troponin of skeletal muscles. This makes cTnT and cTnI more specific for the diagnosis of myocardial injury. These cardiac troponins (cTns) appear in the blood as early as ____ of the acute episode and remain elevated for ____ days.
A different
3-4 hours
4-14
Studies have shown that ______ has replaced _____ as the diagnostic ‘gold standard’ for the diagnosis of myocardial injury.
cardiac troponins; CKMB
New Biomarker
• HEART-TYPE FATTY ACID BINDING PROTEIN-(H- FABP) It is a (low or high?) molecular weight (15 KD) _______ protein present in myocardium and is released into the circulation following myocardial injury. Its plasma kinetics closely resembles those of _____, but it is (more or less?) cardiac specific than myoglobin. It was found to be elevated within ____ after AMI and return to normal levels within _____. Hence it is considered as a sensitive and specific marker of early detection of myocardial injury.
Low
Cytoplasmic
myoglobin
more
3 hours; 12-24 hours
In stable angina, atherosclerotic plaque occludes more than _____% of the vessel
70
