Thrombosis & Embolism
Myocardial Infarction
ECG
Miscellaneous
100
Histologically, how can you differentiate between venous and arterial thrombi?
Arterial thrombi are more laminated- composed of alternating white fibrin/platelets layers and red cells layers.
100
What are the main biomarkers currently used in diagnosis of myocardial infarction?
Troponin I or Troponin T
Additional feedback: creatine kinase MB is also a possible biomarker BUT no longer done in most hospitals
100
What is the duration of 1 large box in an ECG trace?
0.2s
1 small box is 0.04s
100
What are 2 adverse effects of ACE inhibitors?
Dry cough and hyperkalemia
200
Which of the following factors DO NOT predispose to deep venous thrombosis?
Immobilisation
Atherosclerosis
Recent Surgery
Malignancy
Pregnancy
Which of the following factors DO NOT predispose to deep venous thrombosis?
Immobilisation
Atherosclerosis : correct answer
Recent Surgery
Malignancy
Pregnancy
200
What are the two main types of myocardial infarction, and how is each caused?
Transmural (ST elevation) MI - occlusive thrombus
Subendocardial (non-ST elevation) MI - large non-occlusive thrombus that causes sudden significant luminal reduction
200
What are the electrical events which happen during the Q-T interval?
1. Ventricular depolarization (QRS complex)
2. Ventricular depolarization remains (ST segment)
3. Ventricular repolarization (T wave)
200
How does a liver cell respond to low cholesterol content?
Increase cholesterol uptake from the blood by upregulating the number of LDL receptors
Increase cholesterol biosynthesis
500
What is the most likely outcome of venous thromboembolism?
No symptoms
Additional Information:
No symptoms (80%)
Pulmonary Infarction (10%)
Sudden death (rare, due to massive pulmonary embolism in the pulmonary trunk or artery)
Cerebral infarction (more rare, only if the patient has a foraemon ovale, allowing the embolism to bypass the lungs to the brain via the aorta)
500
What type of necrosis occurs during acute myocardial infarction, and what is the characteristic feature of this type of necrosis?
Coagulative necrosis. Characteristic feature is cells have no nuclei but tissue architecture is preserved.
500
Which 2 chest leads out of V1 to V6 mark the transition point?
V3 and/or V4
500
What are the names of these THREE arteries?
A = Right Brachial Artery
B = Right Radial Artery
C = Right Ulnar Artery
800
What are the three factors predisposing to thrombosis in Virchow’s triad?
800
Some patients have no chest pain, and instead only present with sudden onset of dyspnoea, nausea, and vomiting, etc… in which groups of people is this more likely?
Females, diabetics, older patients
800
Beatrice has a transmural myocardial infarction on the inferior surface of her left ventricle. Which 2 chest leads should Eva (Beatrice’s cardiologist) use to have a better view of the infarcted area?
V5 and V6
800
How do statins lower blood cholesterol levels?
Statins inhibit the enzyme, HMG-CoA Reductase, thus inhibiting the synthesis of cholesterol. As a result, the liver cell will increase its uptake of cholesterol by increasing the number of LDL receptors, and thus LDL-cholesterol in the blood will decrease.
1000
In this picture, IDENTIFY where the massive pulmonary embolism is and EXPLAIN the most likely outcome of this person.
The saddle pulmonary embolism obstructs the main pulmonary artery. This most likely led to sudden death through a sequence of events:
1. Right Ventricular Overload: The right ventricle faces acute pressure overload and begins to fail.
2. Reduced Left Ventricular Output: Decreased blood return to the left heart reduces cardiac output.
3. Systemic Hypotension and Hypoxemia: Blood pressure and oxygen drops, leading to insufficient blood flow to the brain and other vital organs.
4. Sudden death within minutes to hours
1000
Based on this image, in which artery was there an occlusive thrombus?
Left descending artery (or anterior interventricular artery)
1000
Match the ECG traces with their respective abnormalities
Options:
Premature Ventricular Contraction
Ventricular Fibrillation
Atrial Fibrillation
ECGs :
A.
B.
C.
1 Matches with C
2 Matches with A
3 Matches with B
1000
How do thiazide diuretics reduce blood pressure?
Thiazide diuretics inhibit the Na/Cl cotransporter in the distal convoluted tubule, thus more Na/Cl stays in the tubular fluid. As a result, more water remains in the tubular fluid and is excreted as urine. Blood volume decreases, so blood pressure is also reduced.