cvd

Question 1

stroke volume

Answer 1

o Stroke Volume is the amount of blood pumped with each heart beat
o Normal volume is 50ml to 100ml
o Determinants of stroke volume are preload, afterload, and contractility
o SV = End-Diastolic Volume – End-Systolic volume
o EDV: amount of blood in ventricles at the end of ventricular diastole
o ESV: amount of blood in the ventricles at the

Question 2

total load

Answer 2

o Total load = preload + afterload
o Contractility may be seen as the ability to overcome load
o The Frank-Starling mechanism describes how contractility is a function of volume
o

Question 3

what is starlings law (stroke volume)

Answer 3

Starling’s Law: The stroke volume of the heart increases in response to an increase in the volume of blood filling the heart

Question 4

ejection fraction
how effectively the hear works
percentages

Answer 4

Ejection Fraction
o Ejection Fraction (EF)
o EF = (SV / EDV) × 100%
o Low EF indicates heart failure or cardiomyopathy
o Normal EF: 50-70%
o High EF: indicative of hypertrophic cardio

Question 5

cardiac output

-equation
-blood
- q

Answer 5

o Cardiac Output is the amount of blood ejected by the heart measured in Liters/minute
o Q = stroke volume x heart rate

Question 6

diagnosis for heart disease ( invasive and non invasive)

Answer 6

o Non-invasive tests: ECG (Holter monitoring), Echocardiography, X-ray, magnetic resonance imaging, positron emission tomography, ultrafast computed tomography scan
o Invasive tests: blood test (heart-damage markers tests), stress test, Catheterization, electrophysiology studies, transoesophageal echocardiogram

Question 7

what is the stages of the ecg

Answer 7

o The P wave represents atrial depolarization
o The PR interval is the time from onset of atrial activation to onset of ventricular activation
o The QRS complex represents ventricular depolarization
o The S-T segment should be iso-electric, representing the ventricles before repolarization
o The T-wave represents ventricular repolarization
o The QT interval is the duration of ventricular activation and recovery

Question 8

what is holter monitoring

Answer 8

o Continuous ECG recording for 24 hours
o More likely to detect an abnormal heart rhythm compared to a short ECG
o Worn during the patient’s regular daily activities
o Correlate symptoms to any abnormal heart rhythm

Question 9

what is exercise stress test

-treadmill and bike
-ecg
- no med

Answer 9

o Use treadmill or bicycle to exercise patient and carry out ECG
o Withdraw from medication for 24-48 hours before the test

Question 10

what is echocardiogram

clue
- ultrasound
- what it can predict and identify

Answer 10

• Echocardiogram uses Doppler ultrasound to create images of the heart
• Provides detailed information on the size of the heart, including chamber size and wall thickness
• Estimates cardiac output, ejection fraction, and diastolic function
• Identifies valvular regurgitation and valvular stenosis

Question 11

what is chest x ray

Answer 11

• Provides an image of the heart, lungs, and bones of the chest
• Does not provide information on the internal structures of the heart
• Identifies the location, size, and shape of the heart, lungs, and blood vessels

Question 12

what is cardiac scintigraphy

clue
- radio labels like th….
- myocardial muscles
- cold spots

Answer 12

• Uses a radiolabelled contrast agent such as thallium201
• Contrast agent is taken up into heart muscle in proportion to localised blood flow and stays in myocardial cells during the scan
• Cold spots on the scan indicate areas of injury

Question 13

what is coronary angiography

Answer 13

• Most direct means of detecting coronary stenosis
• Radiopaque contrast material is injected into an artery and visualized radiographically to locate site of obstruction or presence of atherosclerotic plaque

Question 14

what are the different types of blood tests used to detect cvd

Answer 14

• Platelet function test
• Cardiac enzymes (troponin, myoglobin, CK-MB)
• C-Reactive Protein (CRP)
• Cholesterol/lipids
• Genetic testing for congenital heart disease and non-responders to some medicine

Question 15

what is the platelet function

Answer 15

Platelet aggregation - specialised cell fragments in blood that clump together to prevent bleeding.
•Platelets cause aggregate at sites of vascular injury, stimulated by binding to collagen.
•Platelet clumping at certain sites leads to development of plaque.
•A platelet function test can tell a physician how fast a patient’s blood clots.

Question 16

ck -
clue - damaged tissues

Answer 16

•measure blood levels of the enzyme creatine phosphokinase (CPK; also called creatine kinase (CK) and CK-MB.
•CPK is also released by other damaged tissues in the body (the brain, for example), so a CPK test must be used in conjunction with symptom evaluation and other tests (possibly including other cardiac enzyme tests) to confirm a heart attack.
•CK is an enzyme in muscle tissue throughout the body, including the heart, and CK-MB is an enzyme more specific to the heart.

Question 17

what is creating converted into

Answer 17

creatine ———-> phosphocreatine - high energy compound for muscle contraction

or

creatine ——-> creatinine - used to monitor renal function this is converted through spontaneous cyckizatiob

Question 18

troponin

clue - damaged heart muscles and renal

Answer 18

When the heart muscle is damaged, it releases myoglobin and troponin particular enzymes and proteins into the bloodstream.
•The presence of the protein troponin, which may remain high for one to two weeks.
•Good for diagnosing heart attacks after they have occurred.
•However, troponin levels may be high for non-cardiac reasons as well, most commonly renal (kidney) failure.

Question 19

c reactive protein

clue ; inflammation

Answer 19

•C-reactive Protein (CRP) is a naturally occurring protein that is released at higher levels during inflammation.
•Normal physiological role is to bind to phosphocholine – found on the surface of dead/dying cells; synthesized by the liver in response to factors released by macrophages and adipocytes
•Activates complement system
•The American Heart Association and US Centres for Disease Control and Prevention have defined risk groups as follows:
•Low Risk: less than 1.0 mg/L
•Average risk: 1.0 to 3.0 mg/L
•High risk: above 3.0 mg/L