Week 1 - Mr. Khan presents with Acute Chest Pain Flashcards
Scenario - You are in the emergency department when one of the senior nurses presents you with a 12-lead ECG: “We’ve got a myocardial infarct in a man with central chest pain. Can you see him now?”
- Interpret the ECG?
The ECG is consistent with an acute inferior STEMI with Wenckebach phenomenon.
- ST elevation in leads II, III, and aVF
You are in the emergency department when one of the senior nurses presents you with a 12-lead ECG: “We’ve got a myocardial infarct in a man with central chest pain. His ECG is consistent with an acute inferior STEMI with Wenckebach phenomenon. The nurse tells you that he has no contraindications for thrombolysis. She wants to know if she should get the thrombolytic agent ready. What do you tell her?
- 12 absolute contraindications for fibrinolysis in STEMI?
- 7 Relative contraindications for fibrinolysis in STEMI?
A: Although ‘time is myocardium’, you should not rush into treating the patient with thrombolytic agents until you have taken a good history and examined him properly. You need to ensure that there are no contraindications to thrombolysis in the patient.
What other aspects of the physical examination are critical in a patient presenting with acute chest pain?
Every patient with chest pain must have all peripheral pulses examined and the blood pressure checked in both arms.
The combination of chest pain, blood pressure differential, an ischaemic foot and ECG changes are consistent with a dissecting aortic aneurysm. Thrombolysis would be potentially fatal in this condition. On reflection, you are glad that you routinely check the blood pressure in both arms and examine the peripheral pulses in all patients with chest pain.
Aortic Dissection:
- Epidemiology?
- Aetiology: 6 Acquired causes? 3 Congenital causes?
What are the types of dissecting aortic aneurysms?
What are the 2 systems of classification of aortic dissection?
65% are type A dissections with the tear originating within the proximal ascending aorta. These can propagate both proximally and distally. 30% are type B dissections where the tear is distal to the origin of the (L) subclavian artery with most propagating distally.
There are two classifications of aortic dissection to help direct management. Stanford classification groups dissections by whether the ascending or descending aorta is involved. DeBakey classification categorizes dissections according to their origin and extent.
What is the Stanford classification of Aortic Dissection?
What is the DeBakey classification of Aortic Dissection?
The nurse tells you that she thought that aortic dissection produces a pain that radiates through to the back. Is this true?
Q: If this is an aortic dissection, should you have heard a murmur?
Q: Upon hearing this discussion about her husband, Mrs. Khan says, ‘But Doctor, you told me that the ECG shows a heart attack. Now you are talking about a dissection or something. How can this be?’
Aortic Dissection:
- Pathophysiology?
- Clinical Features? (5)
What tests will help you confirm the diagnosis of aortic dissection? (4)
Pretest Probability?
Use of d-dimer?
Aortic Dissection:
- Diagnostic Approach?
- 3 lab ixs?
- Findings on CXR?
Diagnosis of Aortic Dissection:
- Indications & Findings on CTA chest, abdo, pelvis?
- MRA indications & findings?
- TOE indications & findings?
What is the pathology on this CT?
The intimal flap is in the ascending aorta with the false lumen partially compressing the right coronary artery. The dissection extends down to the left femoral artery.
How do you manage a dissection?
A: Notify a senior immediately that you have made a diagnosis of aortic dissection. You should immediately inform the cardiology and the cardiothoracic surgery team, as the mortality from this condition is about 2-4%/ hour in the first 12 hours. The aim of medical treatment is to reduce systemic hypertension without affecting blood flow to essential organs.
If nitrates do not stop the pain immediately, the patient should receive IV morphine. Reduction of the dP/dt by lowering the BP is usually achieved with IV beta- blockers (metoprolol or labetalol). If BP control is still not achieved, IV nitroprusside can then be used.
What is the treatment for an aortic dissection?
- Surgical therapy?
- Medical therapy?
You commence a GTN and metoprolol infusion and the BP falls. Mrs. Khan wonders whether her husband should be having surgery now instead of medical therapy. What do you tell her?
What does surgery involve?
The cardiothoracic surgical team reviews the patient and agrees that his type A aortic dissection requires immediate surgery. Mrs. Khan is appropriately concerned. ‘Why did my husband get this terrible thing? Is it just bad luck?’
Apart from hypertension, what are the other causal associations with aortic dissection?
