Angina

Question 1

Pathogenesis of angina is?

Answer 1

The increase in myocardial oxygen demand distal to an atheromatous plaque. In stable angina the atheroma decreases lumen size impeding blood flow.

Question 2

How does an atheroma lead to an MI?

Answer 2

The surface of the atheroma becomes ulcerated causing intense platelet aggregation, a thrombus forms and completely occludes a coronary artery.

Question 3

How does an atheroma form?

Answer 3

Irritants such as high LDL, toxins from smoking, high BP causes endothelial dysfunction. LDL moves into the tunica intima. Macrophages envelop LDL and form foam cells. Fibrous cap made up of smooth muscle cells and they add calcium deposits to intima and cap. Blood vessels become crunchy and narrower.

Question 4

What risk factors are modifiable?

Answer 4

Diabetes (good glycemic control), hypertension, smoking, cholesterol levels.

Question 5

Non-modifiable risk factors

Answer 5

Age, first degree relative with ischeamic heart disease less than 60 and being male

Question 6

What investigations would you do?

Answer 6

12 lead ECG, exercise tolerance test, myocardial perfusion scintigraphy, echocardiogram

Question 7

What would you see on a 12 lead ECG?

Answer 7

Often normal but T wave inversion and ST depression can be seen during an attack

Question 8

What would you see on the ECG during an exercise tolerance test?

Answer 8

ST depression

Question 9

How sensitive is the exercise tolerance test?

Answer 9

80%

Question 10

What test might you use in patients with resistant angina, unstable angina, NSTEMI, strongly positive exercise test, ventricular arrythmias?

Answer 10

Coronary angiography

Question 11

What blood tests can you do?

Answer 11

FBC, U+E, creatinine, fasting glucose and lipids. TFTs. Creatinine kinase and troponin are only raised if MI occurs

Question 12

Why do FBCs matter?

Answer 12

Need to exclude anaemia as a cause for chest pain and SOB

Question 13

Why are TFTs done?

Answer 13

As thyroxicosis increases the work of the heart whilst hypothyroidism increases cholesterol levels

Question 14

Why are urea and electrolytes done?

Answer 14

To assess renal function

Question 15

Why is fasting glucose done?

Answer 15

To check for diabetes Normal: 3.9 to 5.5 mmols/l (70 to 100 mg/dl)
Prediabetes or Impaired Glucose Tolerance: 5.6 to 7.0 mmol/l (101 to 126 mg/dl)
Diagnosis of diabetes: more than 7.0 mmol/l (126 mg/dl)

Question 16

Why are fasting lipids done?

Answer 16

To check the cholesterol to HDL ratio

Question 17

What are the types of angina?

Answer 17

Stable, unstable, nocturnal and variant

Question 18

What is the non-pharmacological management?

Answer 18

Risk factor modification

Question 19

What is advised as management of an attack?

Answer 19

Rest
Take GTN
Take a second dose of GTN after 5 minutes if the pain has not eased.
Take a third dose of GTN after a further 5 minutes if the pain has still not eased.
Call 999 for an ambulance if the pain has not eased after another 5 minutes (ie 15 minutes after onset of pain), or earlier if the pain is intensifying or the person is unwell.

Question 20

First line drug treatment?

Answer 20

Beta-blocker or CCB (non-dihydropyradines)

Question 21

If not adequately controlled add what as a second drug?

Answer 21

Ivabradine (funny channel inhibitor reducing HR), Nicorandil (vasodilator to stop vasospasm by inhibiting Rho kinase) or Ranolazine (inhibits by reducing Na entry into Myocytes reducing Ca levels therefore less contractility)

Question 22

When might angioplasty be done?

Answer 22

Those at high risk of MI and subsequent heart failure

Question 23

What is the definition of myocardial ischeamia?

Answer 23

Inadequate oxygen delivery to the heart myocardium