Analytical aspects of cardiac disease(chem Path)

Question 1

What are the four diseases that make up the atherosclerotic cardiovascular disease (ASCVD)?

Answer 1

Coronary heart disease
Cerebrovascular disease
Peripheral arterial disease
Aortic atherosclerotic disease

Question 2

Name two coronary heart diseases

Answer 2

Myocardial infaction
Angina pectoris

Question 3

An example of a cerebrovascular disease

Answer 3

Stroke

Question 4

What is atherosclerosis?

Answer 4

Plaque build up in the arteries, causing stenosis and disruption of the blood flow to the heart and/or other tissues.

Question 5

Syndrome caused by acute disruption of blood flow?

Answer 5

Acute coronary syndrome

Question 6

What does chronic blood flow disruption leads to?

Answer 6

It will cause chronic ASCVD or ischaemic cardiomyopathy which will lead to heart failure.

Question 7

Three types of acute coronary syndrome

Answer 7

1. ST-elevation myocardial infarction (STEMI)
2. Non ST-elevation myocardial infarction (NSTEMI)
3. Unstable angina pectoris

Question 8

Clinical presentation of ACS

Answer 8

-Present with chest pains which radiates to the L arm or jaw.
ECG CHANGES:- ST elevation or depression, T wave changes.

Question 9

How is ACS managed?(2)

Answer 9

Reperfusion
ACS protocol

Question 10

What do we do to patients who present with weakness, abdominal/back pain?

Answer 10

Use Framingham Risk Score

Question 11

How do we differentiate btwn unstable angina, STEMI, NSTEMI? (6)

Answer 11

Unstable angina:normal troponin level, non-specific ecg.
STEMI: High troponin levels, ST elevation.
NSTEMI: High troponin levels, ST depression.

Question 12

What are the requirements for diagnosis of MI?(6)

Answer 12

•An acute rise or fall of cardiac troponin levels with one value> 99th percentile URL and one of the ff:
:-Symptoms of ischemia.
:-New ST-segment changes or a left bundle branch block(LBBB).
:-Presence of a pathological Q wave on ECG.
:-New regional wall motion abnormality on imaging studies.
:-Presence of an intracoronary thrombus on an autopsy or angiography.

Question 13

What are the factors that can negatively affect prognosis of MI?

Answer 13

Diabetes mellitus, delayed reperfusion, previous MI, low ejection fraction, advanced age.

Question 14

What are some of the complications that can occur during a MI?(5)

Answer 14

Emboli
Arrhythmias
Ventricular septal rupture
New-onset mitral regurgitation
Left ventricular aneurysm

Question 15

Why do serum troponin levels increase during an MI?

Answer 15

Fibrous cap of the atherosclerotic plaque ruptures.
Exposing highly thrombotic materials.
Platelets and coagulation factors are activated producing cascade clotting.
Necrosis will then start, which leads to increased troponin levels.

Question 16

What are the proteins of the troponin complex, which ones are cardiac specific and which one are not and state their functions.

Answer 16

Troponin I (cardiac specific):- Inhibits the binding of actin and myosin.
Troponin T (cardiac specific):-Binds the troponin complex to tropomyosin.
Troponin C( non-specific ):- binds to calcium and prevent the inhibitory activity of troponin I.

Question 17

What needs to be tested on suspected MI?

Answer 17

Troponin

Question 18

What is used to detect the troponin levels?

Answer 18

High-sensitivity troponin assays

Question 19

Injury mechanisms of MI, explain

Answer 19

Vaso-occlusive disease:- Rise and fall levels of troponin, atherosclerotic plaque rupture.
Non-occlusive disease:- stable troponin levels, caused by strenuous exercise, drugs, sepsis, myocarditis.

Question 20

Sensitive and specific biomarkers of cardiac injury

Answer 20

Troponin I and T

Question 21

What should you do if the patient has:
1. First Tn=negative, second Tn=negative.
2. First Tn=negative, second Tn level increased but not >/=99th percentile URL or small increase in Tn(<20% initial value).
3. First Tn level=negative, second Tn>/= 99th percentile URL or more than 50% increase in Tn level.
4. First Tn level >/= 99th percentile URL + high index of suspicion.
5. Chronic stable elevations of Tn in patients without acute events-chronic heart disease.

Answer 21

1. If high suspicions, test again in 3-6 hrs. If low suspicions but patient is still ill consider cardio referral and further investigation.
2. Consider other causes of cardiac injury.
3. Rule in MI, manage accordingly.
4. Rule in AMI, reperfusion if STEMI, manage accordingly if NSTEMI.
5. Remember the rise-fall pattern of Tn concentrations in AMI.

Question 22

What is cardiac failure?

Answer 22

A disorder in which the cardiac output is unable to meet the body’s metabolism requirements.

Question 23

What are the symptoms of cardiac failure?

Answer 23

Dyspnoea
Orthopnoea
Lower limb edema
Fatigue

Question 24

What are some of the causes of cardiac failure?(5)

Answer 24

Acute MI
Myocarditis
Congenital heart disease
Atherosclerotic heart disease
Hypertensive heart disease

Question 25

What is NB for clinical diagnosis of cardiac failure?

Answer 25

-Take clinical history and do physical examination.