8/10- Acute Coronary Syndromes at the Bedside Flashcards
- 62 yo man reports 6 mo of chest discomfort on fast walking
- Sx occur every time he walks 500 feet and beyond, are associated with SOB and are relieved after few min of rest.
What is your most likely clinical diagnosis?
A. Unstable angina
B. Acute coronary syndrome
C. Chronic stable angina
D. Prinztmetal’s angina
E. Pericarditis
F. Aortic dissection
G. Pulmonary embolism
What is your most likely clinical diagnosis?
A. Unstable angina
B. Acute coronary syndrome
C. Chronic stable angina
D. Prinztmetal’s angina
E. Pericarditis
F. Aortic dissection
G. Pulmonary embolism
- 30 yo woman reports sudden onset of sharp chest pain, increasing with deep inspiration and lying in the supine position, and relieved by sitting up
What is your most likely clinical diagnosis?
A. Unstable angina
B. Acute coronary syndrome
C. Chronic stable angina
D. Prinztmetal’s angina
E. Pericarditis
F. Aortic dissection
G. Pulmonary embolism
What is your most likely clinical diagnosis?
A. Unstable angina
B. Acute coronary syndrome
C. Chronic stable angina
D. Prinztmetal’s angina
E. Pericarditis
F. Aortic dissection
G. Pulmonary embolism
- This lady is also hypoxemic and tachycardic (not told)
- Pain is sharp (like pulmonary embolism pain) but pain is positional (quite diagnostic for pericarditis)
What are included under “acute coronary syndromes??
Acute Coronary Syndromes:
- Unstable angina
- Myocardial infarction
A pt with stable angina is also described as having what?
Stable CAD (coronary artery disease)
Atherosclerosis causes what main disease?
Coronary heart disease (CHD)
Coronary heart disease may manifest in what 2 main ways?
Categories within these?
Acute coronary syndromes
- Non ST elevation acute coronary syndromes (unstable angina or non-ST elevation MI)
- ST elevation MI
- Sudden cardiac death
Chronic stable angina
What is the pathophysiology of chronic stable angina?
- Stable plaque causing fixed obstruction and exertional symptoms of MI
- Usually when the plaque reaches 70% diameter stenosis in the epicardial coronary artery (typically seen in 4th-6th decades of life)
What is the clinical presentation of chronic stable angina?
Exertional chest discomfort (angina) reproducible at a constant level of effort and of unchanged pattern and severity
What is the overall process of atherosclerosis (leading to chronic stable angina)?
Endothelial injury
- 0% diameter stenosis
- Infancy/childhood-1st decade
Fatty-Streak formation
- 10% diameter stenosis
- 1st-2nd decade
Well developed atherosclerotic plaque
- 70% diameter stenosis
- 4th-5th-6th decade
Why does chronic stable angina correlate with __% diameter stenosis?
When coronary narrowing reaches 70% diameter stenosis, there is no more coronary flow reserve
- The arterioles (in microvasculature) are maximally dilated to increase coronary blood flow maximally at rest (400%) and cannot afford further vasodilation to increase myocardial oxygen supply when needed during exertion (i.e. already working maximal capacity at rest)
- Because of the inability to further increase CBF (b/c coronary flow reserve is abolished) at 70% stenosis, this causes ISCHEMIA (and its clinical manifestations: angina) secondary to IMBALANCE in myocardial O2 demand-supply DURING exertion
With chronic stable angina, what are the symptoms/their pathophysiology that result upon exertion?
(Lack of coronary flow reserve at 70% diameter stenosis causes):
- IMBALANCE in myocardial O2 Demand-Supply during exertion
- ISCHEMIA (secondary to above imbalance) with clinical manifestation of angina
In what ways (list) can chronic stable angina be treated?
- Anti-platelet medication (e.g. aspirin, a thromboxane A inhibitor)
- Anti-ischemic/anti-anginal medications
- Coronary angiography (cardiac catheterization)
- Revascularization
What anti-ischemic/anti-anginal meds can be used to treat chronic stable angina? Effect?
Nitrates + beta blockers (or Ca blockers) to decrease myocadial O2 demand
How/why is coronary angiography (cardiac catheterization) used to treat chronic stable angina?
- To confirm the diagnosis of Chronic Stable Angina (by visualizing the fixed severe but stable coronary narrowing)
- To dictate Revascularization strategy
How is revascularization used to treat chronic stable angina?
Either:
- PCI (percutaneous coronary intervention) with balloon angioplasty and/or stenting (usually for 1 or 2 vessel CHD technically amenable to PCI)
OR
- CABG (coronary artery bypass graft surgery) (usually of 3 vessel CHD, 2-vessel CHD with decreased EF, 2 vessel CHD with proximal LAD, left main CHD)