7 Heart and blood vessels- atheroma

Question 1

Heart and blood vessels- atheroma

Aims

Answer 1

Revise basic cardiac anatomy
Define the term ‘atheroma’
How do atheromatous lesions develop
Possible complications and clinical manifestations of atheroma especially ischaemic heart disease  
Main risk factors involved
Prevention and modification of risks

Question 2

Diseases

Answer 2

Numerous diseases of the heart and blood vessels

Concentrate today on the most common- atheroma and ischaemic heart disease

Some other conditions will be covered in the second lecture

Question 3

Definitions

Answer 3

Atheroma:
“build-up of fatty material on the inside wall of an artery”

Atherosclerosis:
“the progressive narrowing and hardening within an artery potentially resulting in a complete blockage”

Question 4

Epidemiology- atheroma

Answer 4

Contributes to almost half of all deaths in Western countries

Affects arteries- slowly progressive

Lower abdominal aorta, coronary arteries, popliteal arteries, internal carotid arteries and vessels of circle of Willis

Question 5

Pathogenesis

Answer 5

Initiated by chronic injury to the endothelium (response to injury hypothesis) resulting in chronic inflammation

Causes of injury
Hyperlipidaemia, disturbed flow, smoking, hypertension

Progresses as white cells, fat and blood constituents infiltrate injury

Question 6

Clinical manifestation

Answer 6

Can occur in any artery:

Coronary artery- heart attacks/angina(ischaemic heart disease

Aorta- aneurysm due to weakening of the wall

Carotid- narrowing causing strokes

Peripheral vascular disease

Question 7

Complications

Answer 7

Atherosclerotic plaques develop slowly over decades but may acutely cause symptoms due to:
Aneurysm and Rupture
Thrombosis
Haematoma formation
Embolisation
Development of critical stenosis

Question 8

Clinical Manifestation Case 1- Stroke

Answer 8

A 65 year old gentleman with a history of hypertension presents with sudden onset dysphasia, left arm and leg weakness.
He had a similar episode 2 weeks ago, but it only lasted 1 minute.

Question 9

Clinical Manifestation Case 2

Answer 9

A 70 year old gentleman who has smoked for most of his life has attended clinic.

Over the last year he has had severe pain in both his legs when walking for more than 10m, and has had a number of infected ulcers in his feet and lower legs requiring antibiotics.

Question 10

Clinical Manifestation Case 3

Answer 10

50 year old gentleman with type 2 diabetes presents with 30 minute history of ‘central, crushing chest pain’.  
The ECG showed marked ST elevation affecting V1 to V4.  
The gentleman was taken to the cath lab for a revascularisation procedure (primary percutaneous coronary intervention(PCI)).  
MYOCARDIAL INFARCT (Heart Attack)

Question 11

Other presentations

Answer 11

Bowel ischaemia

Renal artery stenosis

Emboli

Question 12

Treatment

Answer 12

Revascularization

Secondary prevention

Question 13

Epidemiology- Ischaemic Heart Disease

Answer 13

Largest single cause of death in the UK
Mortality has fallen considerably over the last few years, interventions more sophisticated
≈ 60 deaths per 100,000 each year
One MI increases risk of developing heart failure and stroke 3-6 fold

Question 14

Aetiology

Answer 14

Imbalance 
between supply (perfusion) and demand of the heart for oxygenated blood

Important:
Not only ↓ oxygen but also ↓ nutrient substrates and inadequate removal of metabolites

Question 15

Causes

Answer 15

Decrease in flow of oxygenated blood

• ateroma
• embolism
• spasm

Increase in demand for oxygen

• Thyrotoxicosis
• Myocardial hypertrophy eg hypertension

> 90% are caused by atherosclerotic obstruction of coronary arteries, coronary artery disease

Question 16

Risk Factors

Answer 16

Fixed

• positive family history
• male sex
• age
• Genetic factors like ACE gene deletion

Potential to be reversible

• Hyperlipidaemia
• cigarette smoking
• Hypertension
• Diabetes
• Lack of exercise
• Obesity
• heavy alcohol consumption

Question 17

Coronary arteries

Answer 17

Plaques can occur anywhere within these arteries

Specific areas relating to coronary artery distribution will be affected

Question 18

Signs & Symptoms

Answer 18

CHEST PAIN, often central, crushing, radiating to left arm or into jaw **
SHORTNESS OF BREATH
PALPITATIONS
SYNCOPE
Nauseous, sweating, pale
** May not get chest pain in elderly or diabetics

Question 19

Clinical presentation and diagnosis

Answer 19

Stable angina
Unstable angina
NSTEMI
STEMI
Sudden death

Question 20

Investigations

Answer 20

Observations: BP, pulse, oxygen saturations, respiratory rate
Bloods (including cardiac enzymes)
Chest X-ray
				*** ECG***
Exercise tolerance test

Question 21

Complications of myocardial infarctions

Answer 21

Cardiac arrest - Ventricular wall rupture
Arrythmias - Deep vein thrombosis
Pericarditis - Pulmonary embolus
Valvular defects

Question 22

Treatment

Answer 22

Immediate & common to all ACS and angina:
Oxygen
Pain relief
Aspirin
ANGINA: Lifestyle, Nitrates (dilates vasculature), B-blockers
ACS: thrombolytic therapy, PTCA, CABG, drugs

Question 23

Hyperlipidaemia

Answer 23

LDL cholesterol – ‘bad cholesterol’, the form of cholesterol that is delivered to peripheral tissues
HDL cholesterol – ‘good cholesterol’, mobilizes cholesterol from the tissues and transports it to the liver to be excreted in bile.

Reduce cholesterol and saturated fats in diet.
Role of statins

Question 24

How to prevent/ modify atheroma?

Answer 24

Stop smoking
Control hypertension
Weight reduction
Increase exercise
Moderation of alcohol 
↑HDL/ ↓ LDL

Question 25

Summary

Answer 25

Meaning of the terms atheroma and atherosclerosis
Pathogenesis and stages of atheroma.
Potential complications of atheroma and introduced how these might present.
Risk factors for atheroma and what can be done in order to reduce these.
Ischaemic heart disease