Exam 1: Ischemic Heart Disease Flashcards
Where are atherosclerotic plaques most likely to form?
Sites of increased blood turbulence or branching points in the epicardial arteries
What is the definition of IHD?
A condition where there is inadequate supply of blood and oxygen to the portion of the myocardium
What is the leading cause of death in the US and what fraction of people does it affect?
CHD.
1/3 of all deaths in individuals over 35
What is the definition of atherosclerosis?
Pathological process causing disease of the coronary, cerebral, and peripheral arteries as well as the aorta
What does nitric oxide do and what cells secrete it?
Produced by endothelial cells.
Inhibits plaque formation and has anti-inflammatory properties
What is metabolic syndrome?
When you have 3 or more of the following:
- Abdominal obesity
- HDL <40 (M) or <50 (F)
- T> 150
- FBG > 110
- HTN
What is the most common cause of death and disability in women in the US?
CHD
Atypical symptoms of CHD are more common in what populations?
Women, elderly, and diabetics
Does angina pectoris result from transient or prolonged ischemia?
Transient
What is stable angina (Angina Pectoris)?
- Chest discomfort thought to be related to ischemia.
- Exertional or stress relegated chest or arm discomfort that resolves with rest and/or nitro
How long does stable angina typically last?
5-10 minutes
What is the character of stable angina?
- Not pain, but heaviness, pressure, and tightness
- Levines sign
- radiation to shoulder, jaw, epigastric, mid back
- 2-10 minutes and crescendo decrescendo
- Tachycardia, hypertensive, abnormal heart sounds
What is Levine’s sign?
A clenched fist over the heart
What are the atypical presentations of stable angina?
Dyspnea (very common in women), nausea, fatigue, and faintness
What is Bruce protocol?
Used for exercise stress tests, speed and incline are increased every 3 minutes until patients HR is at 85% of the max HR predicted for their age.
What kind of tests would you order for stable angina?
EKG, CXR, cardiac enzymes, and stress test (either exercise or nuclear)
-Possibly coronary angiography (cath)
What are the contraindications of an exercise stress test?
Acute MI within 48 hrs, unstable angina, uncontrolled arrhythmia, uncontrolled HF, symptomatic aortic stenosis, uncontrolled HTN, severe PAH, aortic dissection, and acute illness.
What is the gold standard for diagnosing CAD?
Coronary angiography (Cath)
What are the indications for coronary angiography?
- Known or suspected CAD
- atypical chest pain
- before valve surgery
What is the management of stable angina?
- Risk factor modifications such as heathy diet, smoking cessation, weight reduction, HTN treatment, etc
- Medications that decrease oxygen demand, meds that increase oxygen supply, statins, and antiplatelet meds
- Revascularization
CAD is virtually absent in what cultures?
Cultures that eat a plant based diet
What are the medications that decrease oxygen demand?
Nitrates, beta blockers, and CCBs
What medication is first line for acute angina?
Short acting nitrates
What medication is first line for chronic angina?
Beta blockers
How do Beta blockers affect the heart?
Decrease HR, BP, and contractility. Afterload reduction
What is the only antianginal medication proven to prevent re-infarction and improve survival post MI?
Beta blockers
What medication is indicated for patients who dont respond to nitrates and beta blockers?
CCBs
How do CCBs affect the heart?
Decrease BP and contractility. Afterload reduction
How do nitrates affect preload?
They reduce preload
What medications can increase oxygen supply? How?
Nitrates and CCBs
They both act as coronary vasodilators
What is the dosing of nitrates?
0.3-0.6mg sublingually or buccal spray. Give at onset of pain and every 5 minutes after for up to 3 doses. If no improvement, 911 or IV nitro
What are the 3 options for antiplatelet medications?
Aspirin, clopidogrel, or a combo of the 2
What are the benefits of using statins?
- They stabilize plaques
- reduce clinical events
- slow progression or coronary atherosclerosis
- induce regression of coronary atherosclerosis
What are the two types of revascularization?
Percutaneous Coronary Intervention (PCI) or Coronary artery bypass grafting (CABG)
When is a CABG typically performed?
Left main coronary stenosis or triple vessel disease
When is PCI used?
When there is a history of angina despite medical treatment and there is evidence of ischemia on stress testing
What are the 4 pathophysiologic processes that lead to ACS? Which is most common?
1) Plaque rupture or erosion with a superimposed occlusive thrombus (MOST COMMON)
2) Dynamic obstruction
3) progressive mechanical obstruction
4) Unstable angina secondary to increased myocardial oxygen demand and/or decreased supply
What is an example of dynamic obstruction?
Coronary artery spasm (Prinzmetals angina)
What is an example of progressive mechanical obstruction?
Progressive atherosclerosis or restenosis following percutaneous coronary intervention (PCI)
What is the presentation of Prinzmetals angina?
- ischemic symptoms secondary to Vasospasm
- Chest pain occurring at rest with transient ST segment elevation
What is the treatment of Prinzmetals angina?
Nitrates and CCBs
What is the typical presentation of ACS?
Ischemic pain, SOB, weakness, nausea, anxiety, sense of doom
What is the presentation of unstable angina?
- Ischemic discomfort with at least one more of the following:
- Occurs at rest and lasts longer than 10 minutes
- Severe and new onset (in prior 4-6 weeks)
- occurs in crescendo pattern (more severe, more prolonged, more frequent)
Should you stress test when there is suspected unstable angina or NSTEMI?
This is reserved for situations where there is no evidence of infarction, but diagnosis is unclear
Are cardiac enzymes elevated with unstable angina? Are there any EKG changes?
Troponin and CK are NOT elevated.
EKG is usually normal, but there might be ST depression or T wave inversion
Are cardiac enzymes elevated with NSTEMI? Are there any EKG changes?
Troponin and/or CK ARE elevated.
-There may be ST depression or T wave inversion, but no ST elevation on EKG
What medications should be given when patient has NSTEMI or unstable angina?
- Nitro x3 at 5 min intervals
- Beta blockers (Metoprolol or atenolol w/in 24 hrs)
- CCBs if symptoms not relieves with nitro and beta blockers
- High intensity statin (atorvastatin 80mg daily)
- antiplatelet therapy in all NSTEMI if not contraindicated
- Anticoagulation
What are the 7 components of a TIMI score?
- age >65
- > 3 risk factors for CHD
- prior coronary stenosis of >50%
- ST segment deviation on admission EKG
- > 2 angina episodes in the last 24 hrs
- increased cardiac enzymes
- aspirin use in the last 7 days
What does a TIMI score tell you?
Who is likely to progress to a STEMI
What are the identifiable precipitating factors for STEMI that occur in 50% of the cases?
- Vigorous exercise
- extreme emotional stress
- medical or surgical illness
What is the cause of a STEMI?
Most common is rupture of a vulnerable plaque that results in complete occlusion of a coronary artery
What medications should be given when you have a patient with a STEMI?
- ASA 325 chewed
- Nitro
- Beta blockers if not contraindications (metoprolol)
- High intensity statin therapy
What labs should be ordered for management of STEMI?
Cardiac enzymes, electrolytes, CBC, Coags
When should Fibrinolysis be performed with a STEMI?
- if PCI is not available within 120 minutes of first medical contact
- symptoms < 12 hours
- No contraindications
What are the absolute contraindications of Fibrinolytic therapy?
- Hx of intracranial hemorrhage
- hx of stroke in last year
- Poorly controlled HTN
- Suspected aortic dissection
- active internal bleeding
What revascularization strategy is preferred with a STEMI?
PCI
What are the complications that often occur post MI?
-recurrent ischemia, pump failure, ventricular arrhythmia, pericarditis, mural thrombus, cardiac rupture, and depression
What is Dressler’s syndrome?
Chest pain due to pericardial inflammation following MI, CABG, or traumatic injury to the heart.
What is a mural thrombus?
Thrombi that attached to the vessel wall
