Ischemic Heart Disease Part 2 Flashcards
1
Q
If a patient is at high risk of major CAD events or has ACS, what cardiac tests would you do in acute chest pain evaluation?
A
- Invasive coronary angiography
2
Q
If a patient is at a high risk of major CAD events and is being evaluated for stable chest pain outpatient, what tests would be run?
A
Anatomic or functional testing
3
Q
If a patient is at intermediate risk for major CAD events, what testing would be done for acute chest pain or stable chest pain?
A
Anatomic or functional testing
4
Q
If a patient is low risk for major CAD events, how would they be tested for acute chest pain evaluation or stable chest pain evaluation?
A
No testing or defer testing
5
Q
If a patient is asymptomatic, what tests should be done?
A
No testing
6
Q
How is risk for major adverse cardiac event determined?
A
HEART score
7
Q
If a patient has a HEART score of 0-3, what is their risk of MACE in 6 weeks? What intervention should be performed?
A
- Risk of MACE: 2.5%
- Intervention: discharge
8
Q
If a patient has a HEART score of 4-6, what is their risk of MACE? What intervention should be performed?
A
- 22.3%
- Admit for observation
9
Q
If a patient has a HEART score of 7-10, what is their risk of MACE in 6 weeks? What intervention should be performed?
A
- 72.7%
- Admit with early invasive strategies
10
Q
What are uses for a 12-lead EKG?
A
- Assess for MI
- Ischemia
- Cardiac rhythm
- Conduction abnormalities
- Chamber hypertrophy
11
Q
An EKG should be obtained in all adults who have what?
A
Chest discomfort without an obvious non-cardiac cause
12
Q
Who is a 12 lead EKG routinely ordered for?
A
- Elderly patients
- Patients with DM (with dyspnea, nausea, malaise)
- Syncopal patients
- Arrhythmia suspected
13
Q
What are best practices for a 12-lead EKG?
A
- Should be performed and evaluated for ischemic changes for anyone with symptoms of ACS within 10 mins of patient’s arrival at ED
- If initial EKG not diagnostic, but patient still symptomatic and high clinical suspicion for ACS, serial ECGs (15 to 30 min intervals during first 1-2 hrs) should be performed to detect ischemic changes
14
Q
What is sometimes the earliest presentation of AMI?
A
Hyperacute T waves
15
Q
How long are hyperacute T waves found on EKG after the beginning of AMI? What must they be distinguished from?
A
- 20-30 minutes after onset
- Peaked T waves associated with hyperkalemia
16
Q
What is the interpretation of non-specific or normal EKG findings in the presence of ACS symptoms?
A
Does not exclude ACS
17
Q
What is the interpretation of ST segment depression or T wave inversion in >2 contiguous leads in the presence of ACS symptoms?
A
Suspicious for NSTEMI or USA
USA = unstable angina
18
Q
What is ST segment elevation or new LBBB on EKG suspicious for?
A
STEMI
19
Q
What are the steps of STEMI evolution of an EKG?
A
- ST elevation (minutes to hours)
- ST elevation, pathological Q wave, inverted T waves, and scar formation (1-2 days)
- ST flattening, pathological Q wave (7-10 days)
- Normalization with a persistent Q wave (months)
20
Q
What is the second step in evaluation of possible MI (for patients without ST-segment elevations)?
A
Cardiac biomarkers
21
Q
What is the purpose of cardiac biomarkers?
A
Evaluate for myocardial damage
22
Q
What are the cardiac biomarkers?
A
- Myoglobin
- CK-MB
- Troponin I, T
23
Q
When would troponin be elevated?
A
When myocardial necrosis occurs within 3-6 hours
24
Q
What is the preferred marker for myocardial injury because it is highly sensitive and specific for even small amounts of cardiac damage?
A
Troponin
25
How do troponin levels change over time during an MI?
* increase within 3-6 hours
* peak at 24-48 hours
* return to baseline over 5-14 days
26
When should troponin levels be measured?
* At presentation
* Again in 90 minutes
* Every 6-8 hours after symptom onset x 3 or until trending down
27
What are other potential causes for elevated troponin other than MI?
## Footnote
Troponin shows presence of myocardial injury
* CHF
* Sepsis
* PE
* CKD
* Myocarditis
* ESRD
* Aortic dissection
* Cardiotoxic chemo
* Cardiac contusion
* RF ablation
* Post-PCI
* Post CABG
28
What is the normal value for troponin?
essentially 0 (0.0-0.04)
29
When looking at troponin, what has more weight than a single reading
trends
30
This cardiac biomarker is less sensitive and specific than troponins
creatine kinase (CK-MB)
31
How do creatine kinase levels change over time?
* Increase 4-8 hours after injury
* Peak around 24 hours
* Return to normal by 48-72 hours
32
When would CK-MB be positive?
If CK-MB >5% of total CK
33
What can cause false positive CK-MB?
* Exercise
* Trauma
* Muscle disease
* DM
* PE
34
What are the isoenzymes of creatine kinase?
* CK-BB (brain and lungs)
* CK-MB (heart)
* CK-MM (skeletal muscle)
35
This is a cardiac biomarker found in cardiac and skeletal muscle that is released more rapidly from infarcted myocardium than troponin and CK-MB
Myoglobin
36
Is myoglobin sensitive or specific?
High sensitivity, poor specificity
37
This is the most sensitive early marker for myocardial infarction with the only real use in very early detection of an MI
Myoglobin
38
Why is lactate dehydrogenase not used frequently?
Not specific: found in many tissues (kidney, skeletal muscle, brain, blood cells, lungs, liver)
39
What is the timeline of lactate dehydrogenase after an MI?
* Rises within 24-72 hours after MI
* Peaks in 3-4 days
* Returns to normal in 14 days
40
In addition to cardiac biomarkers, what are other possible lab findings in an MI?
* Leukocytosis within several hours after AMI (peaks in 2-4 days and returns to normal levels within 1 week)
* Patients without biochemical evidence of myocardial necrosis but with elevated CRP are at increased risk of subsequent ischemic event
* ESR rises above reference range within 3 days and may remain elevated for weeks
41
What is the most commonly used and recommended noninvasive procedure for evaluating inducible ischemia in the patient with angina?
Stress testing
42
What are the 2 ways the stress component can be added to test for ischemia?
* Exercise
* Pharmacologic
43
When would exercise stress testing be used over pharmacologic?
For patients who can attain an adequate level of exercise
44
What are indications for exercise (only) stress testing?
* To confirm diagnosis of angina
* Determine severity of limitation due to angina
* To assess prognosis in patients with known CAD, including patients recovering from an MI
* To evaluate response to therapy
45
What are limitations of exercise stress testing?
* More false-positives than true-positives
* Not a screening tool in asymptomatic patients
* Most useful in patients with low pretest likelihood and normal baseline EKG
* Typically used in young, females with atypical symptoms
46
What is done in exercise stress testing?
* Incline adjusted via Bruce TM protocol (MC) to achieve 85% HR
* Hemodynamic monitoring of 12 lead EKG, HR, BP
* Intensity of exercise periodically increased until patient reaches maximum HR, changes in heart function detected on EKG, or patient is symptomatic
47
What is considered a positive exercise stress test?
ST segment depression of 1 mm
48
How is the Haskell and Fox HR max calculated?
220-age
49
What are absolute indications for termination of exercise testing?
* Drop in SBP of >10 mmHg from baseline BP despite increased workload when accompanied by other evidence of ischemia or hypoperfusion
* Moderate to severe angina
* Increasing nervous system symptoms
* Signs of poor perfusion
* Subject's desire to stop
* Technical difficulties in monitoring
* Sustained VTach
* ST elevation in leads without diagnostic Q waves
50
What are relative indications for terminating exercise testing?
* Drop in SBP of >10 mmHg from baseline BP despite an increase in workload in the absence of other evidence of ischemia
* ST or QRS changes such as excessive ST depression or marked axis shift
* Arrhythmias other than sustained VT, including multifocal PVCs, V triplets, SVT, heart block, or bradyarrhythmias
* Fatigue, SOB, wheezing, leg cramps, or claudication
* Development of BBB or IVCD that cannot be distinguished from VT
* Increased CP
* Hypertensive response
51
What are absolute contraindications to exercise testing?
* Acute MI (within 2 days)
* High-risk unstable angina
* Uncontrolled arrhythmia causing symptoms of hemodynamic compromise
* Severe symptomatic AS
* Uncontrolled symptomatic HF
* Acute PE or pulmonary infarction
* Acute myocarditis or pericarditis
* Acute aortic dissection
52
What are relative contraindications to exercise testing?
* Left main coronary stenosis
* Moderate stenotic valvular HD
* Electrolyte abnormalities
* Tachy or bradyarrhythmias
* Hypertrophic CM and other forms of outflow tract obstruction
* SBP >220 or DBP >110
* Mental or physical impairment leading to inability to exercise adequately
* High-degree AV block
53
What is an additional contraindication to exercise testing?
* EKG not interpretable due to baseline abnormalities: preexcitation syndrome (WPW), electronically paced ventricular rhythm, greater than 1 mm of resting ST depression, complete LBBB
54
What are indications for exercise stress testing with imaging component?
* Resting ECG makes an exercise ECG difficult to interpret
* Confirmation of the results of the exercise EKG when they are contrary to clinical impression
* To localize the region of ischemia
* To assess the completeness of revascularization following bypass surgery or coronary angioplasty
* As a prognostic indicator in patients with known coronary disease
55
What is used for exercise stress test with nuclear imaging?
Radiotracers of thallium or technetium
56
Why would exercise stress testing with nuclear imaging be used?
Provides relative perfusion data following injection of a radioactive material before and after a stress test
57
What is used for nuclear imaging with an exercise stress test?
SPECT (single photon emission computed tomography)
58
Why is SPECT helpful?
* Provides slices of the heart for imaging
* Enable imaging of wall motion and estimation of EF
59
Why would an exercise stress test be combined with echocardiography?
* Increases sensitivity and specificity and determines extent of myocardium at risk for ischemia
* Looks for regional wall motion abnormalities or LV dilation in response to exercise
60
Why would a pharmacologic stress test be performed?
* If a patient is not able to exercise to a sufficient cardiac workload or has a contraindication to or clinical reason not to perform an exercise stress test
61
What should you keep in mind with a pharmacologic stress test?
Sensitivity is very low so these tests are **always** combined with an imaging modality
62
What medication classes can be used as pharmacologic stress agents? Which one is preferred?
* Vasodilators
* Adrenergic Stimulating agents
* Preferred: vasodilators
63
What vasodilators can be used for a pharmacologic stress test?
* Adenosine
* Dipyridamole
* Regadenoson
64
What is the mechanism of action of vasodilators (adenosine, dipyridamole, and regadenoson) used in pharmacologic stress testing?
* Cause direct coronary artery vasodilation
* Attenuated in diseased coronary arteries which have reduced coronary flow reserve and cannot dilate further in response
65
What are symptoms of vasodilators used as stress agents?
* Shortness of breath
* Headache
* Flushing
* Chest discomfort or chest pain
* Dizziness
* Nausea
* Abdominal discomfort
* Metallic taste in mouth
* Feeling hot
66
What are contraindications to vasodilator stress agents?
* **Bronchospasm**
* SSS or >1 AVB (w/o a V demand PM)
* SBP <90
* Patients using dipyridamole or methyxanthines (ie caffeine and aminophylline)
* Unstable or complicated ACS
67
This medication class is 2nd line for patients who can't exercise and have a contraindication to vasodilator stress
Adrenergic stimulating agents
68
What adrenergic stimulating agent is used as a stress agent?
dobutamine
Often used with atropine in patient who do not achieve target HR
69
What is the mechanism of actionof dobutamine?
* Synthetic cathecholamine
* Directly stimulates both B1 and B2 receptors, causing a dose-related increase in HR, BP, and myocardial contractility
70
What are symptoms of dobutamine?
* Tachycardia
* Increased SBP
* PVCs
* Angina
* Palpitations
* Headache
* Nausea
* Dyspnea
71
What are contraindications to dobutamine?
* Sustained arrhythmias
* Recent MI or unstable angina
* Hemodynamically significant LV outflow tract obstruction
* Aortic dissection
* Moderate to severe systemic HTN (resting SBP >180 to 200 mmHg)
72
How can you definitively diagnose someone with IHD?
Coronary angiogram/cardiac catheterization
## Footnote
Invasive imaging procedure to evaluate heart function
73
How is coronary angiogram/cardiac catheterization used?
* To evaluate or confirm the presence of coronary artery disease, valve disease, or disease of the aorta
* Evaluate heart muscle function
* Determine the need for further treatment
74
What would left heart cath with standard coronary angiography be used to assess?
* Cardiac valves and LV function plus the presence and severity of CAD
* Valvular stenosis and regurgitation can be semi-quantified
* EF and regional wall motion assessed by contrast left ventriculography
* Consequences of regurgitation valvular disease can be better assessed than with echo with doppler US
75
What can right heart cath be used to assess?
* Measurement of RA, RV, PA, and pulmonary capillary wedge pressures, O2 sat, and cardiac output
* Diagnose intracardiac shunts, pericardial disease, right-sided valve lesions and distinguish between cardiac and pulmonary disease
* Pulmonary HTN to determine whether elevated pressures related to pulmonary disease or left heart disease
* Hemodynamic monitoring with PA catheter for assessment and treatment of shock, HF, complicated MI, respiratory failure, and postop hemodynamic instability
76
What is prep for a coronary angiogram?
* Patient must be NPO for 4-6 hours
* Written consent
* IV fluids ran for 24 hours to flush out contrast
* Hold metformin for 48 horus to avoid CIN (contrast induced nephropathy)
77
What are indications for coronary angiogram?
* Life-limiting stable angina despite medical therapy
* High pretest likelihood of CAD
* Concomitant aortic valve disease
* Asymptomatic patients undergoing valve surgery
* Survivors of sudden death, symptomatic, or life-threatening arrhythmias when CAD may be a correctable cause
* Chest pain of uncertain cause or cardiomyopathy of unknown cause
* Emergently for revascularization in patients with STEMI
78
What are risks of coronary angiogram?
Overall low mortality risk
* CVA
* Coronary artery dissection
* Retroperitoneal hemorrhage
* AKI
* Femoral pseudoaneurysm
* Uses IV contrast, so allergies as well as CKD
79
What are problems with coronary angiogram?
Moderate sedation
Invasive and costly so not first-line unless high pre-test likelihood
80
What are relative CI to coronary angiogram?
* Severe renal disease
* Anaphylactic allergy to contrast
81
What non invasive imaging studies may be helpful in IHD?
* CXR
* Chest CT with IV contrast
* Transthoracic echocardiography
* CT of coronary arteries
82
Why might a CXR be helpful with chest pain complaint?
* Identify potential pulmonary causes of chest pain
* May show widened mediastinum with aortic dissection
83
What benefit could a chest CT with IV contrast have to work up of chest pain?
* Can help exclude PE and aortic dissection
84
What benefit could a transthoracic echocardiography study have to working up chest pain?
* Helps identify pericardial effusion and tamponade physiology
* Detect regional wall motion abnormalities
* Help detect regional wall motion abnormalities
* Identify proximal aortic dissection
85
How is a CT of coronary arteries performed?
* Images heart with contrast medium and multislice technology
* Radiation and contrast
* Uses X-ray to produce images of the heart and heart vessels
* HR must be below 50
* If positive, should undergo cardiac catheterization
86
If a patient has stable angina outpatient and a low-intermediate pretest probability based on HEART score, what diagnostic testing should be performed and what would their findings be?
* EKG: likely normal; may see Q-wave non-specific ST changes, LVH
* Labs: CBC, possibly trops, CK-MB
* Non-invasive stress test: if normal, consider other causes; if abnormal refer to cardiology for possible cath
87
If a patient has stable angina outpatient and a high pretest probability based on HEART score, what diagnostic testing should be performed and what would their findings be?
* EKG: likely normal; may see Q-wave, non-specific ST changes, LVH
* Labs: CBC; possibly trops, CK-MB
* Refer for cath
88
If a patient has unstable angina inpatient and a low pretest probability based on the HEART score, what diagnostic testing should be performed and what results would you expect?
* EKG: ST depression, T wave inversions; could be normal
* Labs: troponins (-), +/- CK-MB
* no testing required
89
If a patient with unstable angina has an intermediate pretest probability based on the HEART score inpatient, what diagnostic testing should be performed and what results would you expect?
* EKG: ST depression, T wave inversions; could be normal
* Labs: troponins (-), +/- CK-MB
* Consider further diagnostic testing: stress test with nuclear imaging
90
If a patient with unstable angina has a high pretest probability based on the HEART score inpatient, what diagnostic testing should be performed? What are the expected results?
* EKG: ST depression, T wave inversions; could be normal
* Labs: troponins (-), +/- CK-MB
* Catheterization
91
If a patient has an NSTEMI inpatient, what diagnostic testing would be performed and what are the results if they have a low-intermediate HEART score pretest probability?
* EKG: ST depression, T wave inversions, could be normal
* Labs: troponins (+), +/- CK-MB
* Noninvasive stress test: if normal consider other causes, if abnormal refer to cardio for possible cath
92
If a patient has a NSTEMI inpatient and high pretest probability on HEART score, what diagnostic tests would be performed and what would their results be?
* EKG: ST depression, T wave inversions; could be normal
* Labs: troponins (+); +/- CK-MB
* Cath
93
If a patient has a STEMI inpatient, how would they be worked up and what are the results?
* EKG: ST elevations >1 mm in two contiguous leads
* Catheterization
94
What are the goals of therapy for stable angina?
* Manage symptoms
* Prevent CV events
95
How are symptoms managed with stable angina?
* Nitroglycerin
* Beta blockers
* Calcium channel blockers
* Ranexa
* Revascularization
96
How are CV events prevented with stable angina?
* Risk factor modification
* Antiplatelet therapy
97
How are patients with unstable angina/NSTEMI/STEMI managed?
* Admitted to hospital
* Placed on telemetry/cardiac monitoring
* Strict bedrest
* Supplemental oxygen for saturations <95%
* Nitrates = first-line therapy for ACS with chest pain (.4 mg x 3)
* ASA is first-line therapy (162-325 mg chewed)
98
What are considerations when giving aspirin?
* Give regardless of whether fibrinolytic therapy is being considered or the patient has been taking aspirin
* Chewable has more rapid absorption
* Patients with aspirin allergy should be treated with P2Y12 inhibitor (clopidogrel, prasugrel, or ticagrelor)
99
How is pain with unstable angina/NSTEMI/STEMI managed?
* Morphine for pain refractor to NTG and ASA
* Some patients may require sedation with benzodiazepine
100
What medications should be started in the first 24 hours (not nitrates or aspirin those are immediate) for unstable angina/NSTEMI/STEMI? 48?
* oral Beta blocker
* ACEI or ARB if ACEI not tolerated
* 48: statin, consider adding CCB for persistent ischemia
101
What are contraindications to beta blocker use?
HF, bradycardia, heart block
102
How is a patient with a STEMI treated?
* immediate reperfusion therapy (PCI or fibrinolytic therapy) if within 12 hours of onset
* Primary PCI within 90 minutes of first medical contact is the goal and is superior to thrombolysis
* Thrombolysis within 30 minutes of hospital presentation and 6-12 hrs of onset of symptoms reduces mortality
## Footnote
Dead meat don't beat! Time is muscle!
103
What is the MOA of nitroglycerin?
Nitrate enters vascular smooth muscle and is converted to nitric oxide, leading to activation of cGMP and vasodilation
* Dilates coronary vessels, increasing blood flow
* Decreases SVR and preload
104
Which patients should you use nitrates with caution in?
* Hypotension (SBP <100)
* Bradycardia
* Tachycardia
* RV infarction
105
What are SE of nitrates?
Reflex tachycardia, can cause paradoxical bradycardia
* Headache MC (can be severe)
* Postural hypotension
* Tolerance
106
What is the first-line therapy for patients with acute coronary syndromes presenting with CP? (Except in patients presenting with IWMI)
## Footnote
IWMI = inferior wall MI
Nitrates (Nitroglycerin)
107
What is the route of nitrates?
Sublingual, oral, NTG ointment, spray
108
What should be done if pain persists or recurs after treatment with nitrates?
* Start IV NTG until angina disappears or MAP drops by 10%
* Continuous BP monitoring is required with IV NTG
109
What should be kept in mind related to tolerance with nitrates?
* Repeated or continuous exposure to high doses can lead to tolerance
* Magnitude of tolerance is function of dosage and frequency of use
* Prolonged use may not only induce loss of response to nitrates but also decrease angina threshold
* High doses should be avoided and therapy interrupted for 8-12 h daily "Treatment holiday"
110
What is the contraindication for nitrates?
Nitrates and PDE5 inhibitors
* Accumulation of cGMP enhanced by inhibition of cGMP specific PDE5 family
* PDE5 inhibitors and nitrates act synergistically to cause increases in cGMP and dramatic reductions in BP
* PDE5 inhibitors should not be prescribed to patients receiving long-acting nitrates
* Use extreme caution with PRN nitrates (none can be given within 24 hours of PDE5 drug)
111
What is the function of morphine in IHD?
* Reduce pain/anxiety
* Decreases sympathetic tone, SVR, and O2 demand --> reduced afterload
112
Which patients should morphine be used with caution in?
* Hypotension
* Hypovolemia
* Respiratory depression
113
What are SE of morphine?
* Bradycardia
* Diaphoresis
* Nausea
* Constipation
* Drowsiness
* Dizziness
* Confusion
114
What is the mechanism of action of aspirin?
* Irreversible inhibition of platelet aggregation
* Stabilization of plaque
* Stop thrombus formation
* Reduce mortality in patients with STEMI
115
Who should you use caution with aspirin use?
* Active PUD
* Hypersensitivity
* Bleeding disorders
116
What are SE of aspirin?
* GI (ulcers, dyspepsia, hemorrhage)
* Increased bleeding risk
117
How much aspirin should be given for ACS?
* 160-325 mg chewed
* 81 mg preferred over higher doses for long-term therapy
118
What is the mechanism of action of P2Y12 inhibitors?
* Irreversible inhibition of platelet aggregation
* Used in support of cath/PCI or if unable to take aspirin
119
How long is treatment with P2Y12 inhibitors?
3-12 mo
120
What are the P2Y12 inhibitors?
* Clopidogrel
* Prasugrel
* Ticagrelor
121
What should be given prior to cardiac cath?
Plavix (600 mg)
122
What should you do if a patient is receiving a CABG and is on P2Y12 inhibitors?
* Postpone elective CABG at least 5 days after the last dose of clopidogrel or ticagrelor and at least 7 days after the last dose of prasugrel due to risk of bleeding
123
What are the glycoprotein IIb/IIIa inhibitors?
* Tirofiban (Aggrastat)
* Eptifibatide (Integrilin)
* Abciximab (Reopro)
124
What is the mechanism of action and indication of glycoprotein IIb/IIIa inhibitors?
* Inhibition of platelet aggregation at final common pathway
* Support of PCI intervention as early as possible prior to PCI
* May be considered in high risk patients ie ongoing ischemia despite ASA and P2Y12 inhibitor; large thrombus discovered during angiography, especially if they have not received prasugrel or ticagrelor
* To stabilize patients who need urgent CABG in place of P2Y12 until surgical indications defined
125
Which anticoagulant therapy can be given?
indirect thrombin inhibitors
* UFH
* LMWH: enoxaparin, fondaparinux, dalteparin
Direct thrombin inhibitors: bivalirudin (angiomax
126
What is the function of anticoagulation therapy in IHD?
* Adjunct to surgical revascularization and thrombolytic/PCI reperfusion
* Used in combo with ASA and/or other platelet inhibitors
127
Studies have shown that which medication is somewhat more effective than UFH in preventing ischemic events in the setting of acute coronary syndromes?
LMWH
128
What is a reasonable alternative to heparin according to the ACUITY trial?
bivalirudin plus a glycoprotein IIb/IIIa antagonist
129
what beta blockers are used in IHD?
* metoprolol tartrate
* carvedilol
130
How do beta blockers impact mortality risk?
14% reduction in mortality risk at 7 days and 23% long term mortality reduction
Should be started 24-48 hours after MI once patient is stable
13% reduction in risk of progression to MI in patients with threatening or evoking MI symptoms
131
What do beta blockers reduce?
* Infarct size and complications
* Rate of re-infarction
* Rate of life-threatening tachyarrhythmias and thus mortality
* Prevent cardiac enlargement and remodeling
132
What are contraindications to beta blocker use?
acute CHF
heart block
hypotension
133
What is the antianginal medication to treat chronic angina?
Ranexa
134
What is the MOA of ranexa?
Late sodium channel blocker, decreases intracellular calcium overload
135
When is ranexa used?
chronic, stable angina
136
What are advantages of ranexa?
* no effect on HR or BP
* Safe to use with ED drugs
137
What are disadvantages of ranexa?
* May prolong QT so avoid use with other QT prolongation drugs
* Difficult to get insurance to cover/costly
138
Why are ACEI helpful post-MI?
* Post-MI there is a progressive increase in ACE activity and AT type I receptor activity at the healing infarct site and at other remote sites in the LV
* Use of ACE-I and ARBs reduces fibrosis and remodeling at the scar site and remote to the infarct
* Can help preserve myocardium in setting of MI
139
What additional medications can be helpful for post-MI?
* Statins
* Warfarin
* Aldosterone antagonists
* Calcium channel blockers
140
Which patients benefit from warfarin?
Selected cases with intracardiac thrombus or embolic events
141
Which patients may benefit from aldosterone antagonists?
* Selected patients with LV dysfunction
142
What are calcium channel blockers generally used for?
* 3rd line therapy in patients with continuing symptoms on nitrates and beta blockers or those who are not candidates for these drugs
143
Which calcium channel blockers are more likely to cause reflex tachycardia or hypotension in presence of nitrates without accompanying BB?
DHP
Diltiazem or verapamil are preferred
144
What is the only indication for fibrinolytics in IHD?
STEMI if and only if cardiac catheterization can't be done within a few hours of the ischemic event
145
What are fibrinolytics used in STEMI?
Alteplase and tenecteplase
146
What complication of fibrinolytic therapy can occur?
Major bleeding complications
Most serious = intracranial hemorrhage
147
How are post-STEMI patients managed after completion of the fibrinolytic infusion?
* Aspirin and anticoagulation until revascularization or for the duration of the hospital stay
148
What anticoagulation is preferred with aspirin after fibrinolytic in STEMI?
LMWH (enoxaparin)
149
What is the goal of initiation of fibrinolytic therapy if catheterization is not available?
within 30 minutes of arrival at ED
150
What timing of thrombolytic therapy reduces mortality?
Within first 6-12 hours of onset of symptoms
Greatest benefit is within first 3 hours after onset of presentation
151
What can be done if there is failure of reperfusion and pain and ST elevation persist >90 minutes after bolus in?
Salvage angioplasty
152
What should all patients with stemi treated with antithrombotic therapy be started on?
Prophylactic treatment with PPIs or antacids and an H2 blocker while hospitalized
153
How is reinfarction treated?
Readministration of a thrombolytic agent or immediate angiography and PCI
154
What are absolute contraindications to thrombolytic therapy?
* Any prior intracranial hemorrhage
* Known structural cerebral vascular lesion
* Known malignant intracranial neoplasm
* Ischemic stroke within past 3 months
* Active internal bleeding
* Suspected aortic dissection
* Active bleeding or bleeding diathesis (not menses)
* Significant closed head or facial trauma
155
What are relative contraindications to thrombolytic therapy?
* Known bleeding diathesis
* Trauma within the past 2-4 weeks
* Major surgery within past 3 weeks
* Prolonged or traumatic CPR
* Recent internal bleeding
* Noncompressible vascular puncture
* Active diabetic retinopathy
* Pregnancy
* Active PUD
* Current use of anticoagulants
* BP >180/>110
156
When does PCI have a benefit?
Unstable disease
157
How does PCI compare to thrombolytics for opening occluded arteries?
More effective
158
How should patients be managed after PCI?
Should receive dual antiplatelet therapy (DAPT)- ASA + P2Y12 receptor blocker for 3-12 months to reduce the risk of MI or death
159
What are the 2 types of angioplasty?
Balloon and stent
160
What is balloon angioplasty?
* Minimally invasive procedure to open blocked arteries
* Inflation of a balloon within the coronary artery to compress plaque against walls of the artery and open the lumen
* Rarely the only procedure performed
161
What is stent angioplasty?
* Insertion of small, expandable mesh-like tube of thin wire along with the balloon
* Stent placed around the balloon in a compressed form and then guided to site of blockage
* When balloon inflated, stent expands and compresses the plaque
* Balloon deflated and removed, leaving behind the stent which acts as a support and helps keep artery open
162
What are types of stents for PCI?
* Bare metal stents
* Drug-eluting stents
163
What is a bare metal stent? What are disadvantages?
* Vascular stent without a coating
* Restenosis after one year is relatively high due to development of neointimal hyperplasia
164
What are drug-eluting stents? What is its benefit? What is its risk?
* Stent that slowly releases a drug to block cell proliferation
* Reduce restenosis so is preferred stent
* require longer period of DAPT to prevent stent thrombosis so not appropriate for all patients
165
What is atherectomy (roto-rooter)?
* Specialized catheter used for mechanical removal of plaque from arterial walls
* Plaque scraped or pulverized with tiny blades
* Ensures that arterial wall remains damage-free
166
What needs to be added post atherectomy?
* DAPT
167
What is a CABG?
* Procedure in which artereis or veins are harvested from elsewhere in the body and are grafter to the coronary arteries to bypass atherosclerotic narrowing and improve blood supply to the myocardium
168
What are CABG indications?
Preferred method for revascularization in patients with the following conditions:
* Left main trunk artery stenosis
* Poor LV function
* Significant 3-vessel CAD or 2-vessel disease that involves the proximal LAD
* DM with focal stenosis in more than 1 vessel
* Concomitant severe valvular disease that necessitates open heart surgery
* Diffuse disease not amenable to treatment with PCI
169
How is the CABG procedure performed?
* Heart stopped with use of cardiopulmonary bypass but more and more surgeries are being done "off pump" with the heart still beating
170
What is enhanced external counterpulsation?
* Non-invasive procedure performed on individuals with angina or HF or cardiomyopathy in order to diminish symptoms of ischemia, improve functional capacity, and quality of life
* Cuffs placed around lower extremities and inflate and deflate in rhythm with cardiac cycle
171
What is the goal of enhanced external counterpulsation?
* Reduce cardiac workload and improve blood flow to the heart
* Has been shown to relieve angina and decrease degree of ischemia in cardiac stress test
