L44 Clinical Approach to the Patient with Chest Pain Flashcards
Why is chest pain a clinical challenge?
- Frequent overlap of signs and symptoms
2. Common mechanism of pain perception (same spinal cord sensory innervation)
The majority of non-emergent chest pain is ___ in origin. What are the 2nd and 3rd most common causes?
Musculoskeletal; GI; cardiac
What are the 4 killer chest pain causes?
- Acute coronary syndromes (unstable angina, NSTEMI, STEMI)
- Pulmonary Embolism
- Aortic Dissection
- Tension Pneumothorax
What are some common cardiac causes of chest pain?
- Angina
- MI
- Aortic valve disease
- Hypertrophic or congestive cardiomyopathy
- Aortic dissection
- Pericarditis
- Mitral valve prolapse
What are the classic signs of angina pectoris?
Grasping the chest, pain across the substernum, radiates down the left arm, drop what is being carried, precipitated by a heavy meal, cold, exertion, and hypoxic environments
After the substernum, what are the most common areas for angina to present?
Jaw, epigastrum, inner aspect of the left arm
What types of pain are rarely/never cardiac in origin?
Pain or pressure lasting seconds (sharp, stabbing), under the left breast, and below the umbilicus
What are some physical signs of a patient in acute CAD?
Pallor, sweating, anxiety, tachycardia, rise in blood pressure, S4 gallop, mitral regurgitation murmur, paradoxically split S2, pulsus alternans
What causes pallor, sweating, anxiety, tachycardia, and rise in blood pressure?
Sympathetic stimulation by pain
What causes an S4 gallop?
Decreased LV compliance due to ischemia or infarction
What causes mitral regurgitation?
Inferior wall ischemia or infarction
What causes a paradoxically split S2?
New left bundle branch block and possible acute MI
What causes pulsus alternans?
Impending LV failure and cardiogenic shock
Describe the pathophysiology of unstable angina and acute MI.
A non-vulnerable atherosclerotic plaque becomes vulnerable by developing a lipid core. Physical or mental stress can trigger a plaque rupture. Rupture leads to formation of a thrombosis (either occlusive or non-occlusive). The non-occlusive thrombus can be asymptomatic or cause unstable angina or Non-Q MI. Occlusive thrombus causes MI or sudden cardiac death.
In an acute MI, discuss the % of normal, abnormal, and typical ECG that will present.
10% normal
40% abnormal, but non-diagnostic
50% typical
What are the characteristic features of ECG when a patient has an acute infarction?
- Elevated ST segments
- Inverted T waves over time
- Development of Q waves within 12 hours
What issues look like acute MI on ECG?
- Pericarditis
- J-point elevation
- WPW syndrome
When is it difficult to use ECG to diagnose MI?
- LBBB
2. Patient with a pacemaker
ST depression represents ___; ST elevation represents ___.
Ischemia; infarction
What biomarker is diagnostic for acute coronary syndrome/cardiac injury?
Troponin ( and T)
In addition to being diagnostic, troponin is also ___.
Prognostic
What is stable angina?
Angina that occurs at a predictable amount of energy expenditure or emotion.
What are the measurable signs of ischemia over time (in order).
- Relaxation failure
- Contraction failure
- Filling pressure increases
- EKG changes
- Angina
Describe the classes of angina pectoris according to Canadian Classification.
I: ordinary activity does not cause angina; occurs with strenuous activity
II: slight limitation of ordinary activity; occurs with walking rapidly/uphill
III: marked limitations of ordinary physical activity
IV: inability to carry on any physical activity without discomfort, may be present at rest
