Introduction to Cardiovascular Disease

Cardiovascular Disease (CVD)

• CVD refers to a group of disorders of the heart and blood vessels
• 7.6 million people in the UK live with CVD
• 450 deaths occur daily in the UK due to CVD
• CVD accounts for 100,000 hospital admissions annually in the UK
• CVD is the leading cause of death globally
• The total annual healthcare cost of CVD in the UK is £9 billion

Types of CVD

• Coronary heart disease
• Cerebrovascular disease
• Peripheral vascular disease
• Deep vein thrombosis and pulmonary embolism
• Valvular heart disease
• Congenital heart disease

Risk Factors for CVD

• Lifestyle:
  • Unhealthy diet (high salt intake)
  • Physical inactivity
  • Obesity
  • Smoking
  • Alcohol
• Other:
  • Hypertension
  • High cholesterol
  • Diabetes
  • Kidney disease
  • Age
  • Gender
  • Ethnicity
  • Family history

Atherosclerosis

• The underlying cause of most CVD
• Narrowing of arteries due to the build-up of plaques (atheroma)
• Restricts the flow of oxygen-rich blood to organs
• Caused by damage to the endothelium of the artery, triggering a chronic inflammatory response

Stages of Atherosclerosis

• Endothelial injury or dysfunction
• Fatty streak - Lipids accumulate beneath the damaged endothelium
• Inflammatory response – Recruitment of white blood cells and foam cell formation
• Plaque progression – migration of smooth muscle cells, increased connective tissue, calcification, platelet adhesion and fibrous cap formation
• Plaque disruption

Risk Factors for Atherosclerosis

• Physical stress on arteries (turbulent flow at branch points)
• Smoking/air pollution (circulation of reactive oxygen radicals)
• Dyslipidaemia (High total cholesterol, high LDLs, low HDLs)
• Chronically elevated blood glucose levels

Complications of Atherosclerosis

• Thrombosis - Complete blockage (occlusion) of the artery
• Infarction - Tissue death due to impaired blood flow
• Embolus - A blood clot that travels in the bloodstream and can block an artery
• Ischaemic heart disease, Angina, Myocardial infarction (heart attack), Cerebrovascular disease (stroke), Aneurysm, Peripheral vascular disease

Ischaemic Heart Disease

• Restriction of blood supply to tissues
• Caused by atherosclerosis and hypertension
• Leads to angina pectoris and myocardial infarction
• Infarction can lead to acute circulatory failure, loss of cerebral blood supply and death
• Risk factors: age, smoking, hyperlipidaemia, diabetes, hypertension

Hyperlipidaemia

• High blood cholesterol
• May be familial (inherited)
• Associated with: age, gender, inactivity, being overweight, low dietary fiber, smoking, ethnicity, low socioeconomic status and other diseases (hypertension, diabetes and chronic kidney disease)
• Management aims to lower LDL levels and raise HDL levels through lifestyle changes
• Statins may be required

Angina Pectoris

• Chest pain caused by narrowing of the coronary arteries
• Associated with myocardial ischaemia and increased blood lactic acid
• Squeezing, crushing, gripping substernal pain (may radiate to left arm/jaw)
• Can be stable or unstable

Angina Pectoris - Management

• Relieved by rest or glyceryl trinitrate (GTN) medication
• GTN stimulates vasodilation, resolving pain within 2-3 minutes
• Other medications may be required - Aspirin, calcium channel blockers, beta blockers, ACE inhibitors, statins
• Angioplasty or surgery to place stents or perform a coronary artery bypass graft may be required

Myocardial Infarction

• Heart attack or coronary thrombosis
• Sudden injury caused by blockage of a coronary artery
• Rupture of a vulnerable atheromatous plaque
• Ischaemia (oxygen shortage) leads to necrosis (tissue death) of the myocardium

Myocardial Infarction - Clinical Presentation

• Severe, central crushing pain radiating to left arm or jaw
• May start at rest and persist
• Restlessness, facial pallor, sweating, nausea, vomiting, confusion and apprehension
• 10-20% of patients experience no pain (silent infarctions)
• Women may present with atypical symptoms
• Death can occur soon after the onset of chest pain due to ventricular fibrillation and cardiac arrest

Myocardial Infarction - Management

• Call 999 for emergency assistance
• Immediate hospital admission
• Comfortable position
• GTN spray if known angina
• Dispersible aspirin 300mg chewed (unless clear evidence of allergy)
• Oxygen if the patient is hypoxaemic
• Monitor and be prepared to start CPR/AED
• ECG, blood tests, echocardiogram
• Oxygen
• Thrombolytic therapy
• Analgesics
• Anticoagulants
• ACE inhibitors
• Sedatives
• Bed rest
• Surgery

Myocardial Infarction - Complications

• Outlook depends on the time from onset to treatment
• Acute - cardiac dysrhythmias, cardiac failure and pericarditis
• Later – angina, thromboembolism, aneurysm, cardiac rupture
• Longer term - post MI syndrome (known as Dressler’s syndrome), shoulder-hand syndrome, psychological problems and depression

Cardiac Arrest

• Abrupt loss of heart function, breathing and consciousness
• Electrical malfunction in the heart prevents oxygenated blood being pumped to the brain, lungs and other organs
• Can occur after a myocardial infarction but often has other causes

Consequences of Cardiac Arrest

• Cerebral hypoxia causes respiratory arrest and brain injury
• Survivors may experience personality changes, memory and speech impairment, involuntary movements, and incontinence

Management of Cardiac Arrest

• The longer the arrest lasts, the less likely a healthy life can be restored
• Chain of survival:
  • CPR to provide circulatory support
  • AED if shockable rhythm present (ventricular fibrillation or pulseless ventricular tachycardia)

Maintaining Knowledge for Dental Emergency Management

• Ongoing professional development, including CPD courses
• Continued exposure to emergency situations via simulations and clinical practice
• Membership of professional organizations that provide resources and training
• Maintaining up-to-date knowledge of relevant clinical guidelines
• Staying informed about current research and advancements in emergency medicine