Cardiology investigations in practice

Question 1

What condition is it important to check blood pressure in both arms?

Answer 1

dissecting aneurysm

Question 2

What factors influence what investigations you choose to carry out?

Answer 2

urgency 
invasiveness 
acceptability to patients 
patient suitability 
time - waiting lists, length of time to undertake test, speed of result availability

Question 3

Define sensitivity

Answer 3

test’s ability to correctly detect patients who have disease X (true positive_

Question 4

Define specificity

Answer 4

test’s ability to correctly detect patients without disease (true negative)

Question 5

What are the indications for ECGs?

Answer 5

1) investigate conduction problems
2) diagnose cardiac conditions such as acute coronary syndrome
3) under exercise conditions in suspected myocardial ischemia
4) indicate non-cardiac abnormalities e.g. electrolyte imbalances

Question 6

What are some examples of specific types of ECG?

Answer 6

holter monitor - 24 hour tape

reveal device - implanted just under the skin in thorax to measure electrical activity of heart

Question 7

When is troponin released?

Answer 7

released from myocytes when irreversible myocardial damage occurs
highly specific to cardiac tissue
dependent on infarct size

Question 8

What are the preferred troponins in practice?

Answer 8

high sensitivity cardiac troponin T and I are preferred markers for MI - interpret results alongside clinical findings and ECG

Question 9

When do serum troponin levels increase?

Answer 9

increase within 3-12 hours from onset of chest pain - peak at 24-48 hours and return to baseline over 5-14 days

Question 10

When should troponin levels be measured?

Answer 10

measured at presentation and again approximately 10-12 hours after symptoms

Question 11

What is the best early cardiac marker of damage?

Answer 11

myoglobin but it has poor specificity

Question 12

What other conditions can cause raised troponin?

Answer 12

common

1) sepsis
2) acute PE
3) chronic kidney disease
4) congestive HF

less common

1) myocarditis
2) aortic dissection

Question 13

What is b-type natriuretic peptide (BNP)?

Answer 13

cardiac marker secreted by cardiac ventricles in response to excessive stretching
marker of pressure and volume overload
indicator of HF in practice

Question 14

What information can you get from echocardiography?

Answer 14

visualization of cardiac structures and velocity of blood flow

• chambers and valves
• also functional factors = intra-cardiac hemodynamics, LVEF,regional wall abnormalities, thrombus (endocarditis)

Question 15

What is coronary angiogram and how is it performed?

Answer 15

Establish blood flow in coronary arteries and hemodynamics

via femoral or radial artery, fluoroscopy guided

can intervene e.g. with stents

Question 16

What are the major reasons for ordering a laboratory or other test in practice?

Answer 16

diagnosis
monitoring
screening
research