Cardiovascular Disease II

There are not many Cardiovascular Diseases however they all tend to cause each other.

Describe How

If you have pre-existing valve disease your more likely to get endocarditis which can cause heart failure and arrhythmia or an MI. We rarely see one disease in isolation. They all tend to aggregate together. But usually there's at least one which is the predominant problem

List three investigations that can be done to detect Coronary Artery Disease

1. Exercise ECG

2. Myocardial Perfusion Scan

3. Angiography (CT or Invasive)

Which of the three Coronary Artery Disease investigations if most accurate

Angiography

Previously What was the standard test to investigate if a patient has Coronary Heart Disease

Exercise ECG

Currently, what is the first line investigation for people who may have Coronary Artery Disease

Angiography

What are the problems with Exercise ECGs

• 50% of women would have ECG changes upon exercise even if they do not have Coronary Artery Disease

• ECG changes can be normal in patients with Coronary Artery Disease.

Exercise ECGs are Easy & Cheap but inaccurate.

What is Coronary Angiography

Insert a Tube into the Femoral Artery of the wrist and inject some x-ray dye. When dye is injected into the coronary arteries to map vascular damage

What is Myocardial Perfusion Scan

Test done to investigate coronary artery disease.

Patient is injected with radiolabelled tracer. The tracer travels in the blood and gets absorbed by the Heart.

At rest, all of the tracer is absorbed by the heart.

When the Heart is stressed, all/none of the tracer may not be absorbed by the heart. This is evidence of impairment of blood flow to that region as the tracer is not getting there.

Coronary Artery Disease can be treated with Lifestyle Modifications.

List Lifestyle Modifications that can be implemented to reduce the risk of Coronary Artery Disease (7)

1. Stop Smoking

2. Regular Exercise

3. Eat Healthy Diet

4. Low Processed Foods

5. High in Oily Fish, Olive Oil and Nuts/Seeds

6. Loose Weight

7. Diet Low in Salt.

Medications Used to Lower Cholesterol can be taken in the Management of Coronary Artery Disease

List Medications that Lower Cholesterol

Statins

Cholesterol can also be lowered through Diet Management

What is the Effect of Antiplatelets like Aspirin on Coronary Artery Disease

Aspirin Lowers the risk of MI

To Treat Coronary Artery Disease, other systemic risk factors need to be controlled.

Give Examples:

1. Blood Pressure

2. Diabetes

3. Psychological Issues i.e. Stress and Anxiety

4. Quit Smoking!

List 4 Treatments and Managements of Coronary Artery Disease

1. Lifestyle Modification

2. Cholesterol Lowering (Statin)

3. Antiplatelet Therapy (Aspirin)

4. Address Systemic Risk Factors i.e. Blood Pressure, Diabetes etc.

Coronary Artery Disease that causes Angina needs to be treated differently

What is the treatment in this case.

Coronary Artery Disease management alongside

Drugs to reduce Anginal Attacks i.e. GTN, Beta Blockers, Calcium Channel Blockers

Other Drugs such as: Nicorandil, Ivabradine, Ranolazine.

If Medications do not work consider Stenting or Coronary Artery Bypass Grafting

What is Nicorandil

A Potassium Channel Opener

What is Ivabradine

Inhibits pacemaker current in SA node to reduce Heart Rate.

What investigations are done to diagnose a Myocardial Infarction (2)

1. ECG

2. Serum Troponin Measurement

What type of MI is it if the ECG shows ST elevation

ST Elevation MI

What type of MI is it if the ECG is normal or shows other changes such as ST Depression, T Wave Inversion?

Non-ST Elevation MI (NSTEMI) or could just be Trapped Wind.

Describe the Serum Troponin Levels in STEMI and NSTEMI

In both STEMI and NSTEMI the serum Troponin levels will be raised. Although this may take time.

Why may Serum Troponin Levels raise during an MI

Anything that damages your heart will raise your troponin levels i.e. Car Accident, MI or Operation on the Heart.

If Serum Troponin levels increase and the patient complains of Chest Pain it is likely to be an MI

When are Serum Troponin Levels measured

Measure Serum Troponin Levels when the Patient Arrives in A&E and then 6 Hours after the onset of Chest Pain.

What triggers Blood Clot Formation in an Artery

The Artherosclerotic Plaque has ruptured causing Blood to Clot.

What is the Management of STEMI and NSTEMI

1. Immediate Dual Antiplatelet Therapy (Asprin + 1 of 3 (Ticagrelor, Prasugrel or Clopidogrel)

2. Anticoagulation for 24-72 hours (Heparin or Fondapariux)

3. Angiogram (Immediately for STEMI, within 72 hours for NSTEMI unless complications)

Early Priority Treatment of STEMI and NSTEMI is the treatment of the Thrombosis.

How is the Thrombosis treated

Immediate DAPT (Dual Antiplatelet Therapy)

Aspirin plus one of the following 3, Ticagrelor, Prasugrel and Clopidogrel.

Pain Relief may also be prescribed.

Why are Nitrates not prescribed during an STEMI or NSTEMI

Nitrates are useful for Anginal Attacks but have no effect on MI and do not improve the symptoms

When should Oxygen be prescribed during an NSTEMI or STEMI

Oxygen should only be given if the patient is Hypoxic

Both STEMI and NSTEMI should have Angiography as part of their treatment. However the time in which they have this differs between the two conditions.

Explain How.

Angiograms are done Immediately in STEMI whereas in NSTEMI they are done within 72 hours or soon if there are complications.

For how long are Anticoagulants prescribed after an NSTEMI or STEMI

Anticoagulation for 24 to 72 hours.

Heparin, Fondapariux (indirect inhibition of Factor Xa)

What is the Secondary Prevention in the Management of STEMI and NSTEMI

Dual Antiplatelet therapy for 1 year followed by Aspirin Alone

Statins

Betablockers for 1 year

ACE inhibitors

Cardiac Rehabilitation including Exercise, Education, Diet and Smoking Cessation.

How is Heart Failure Investigated

Transthoracic Echocardiography

• This is a non-invasive ultrasound test.

Serum Tests for B-Type Natriuretic Peptide (BNP) can be done. BNP is usually elevated in Heart Failure. However Heart Failure is not the only cause of elevated BNP but usually is the main cause.

Patients may also have an MRI scan

What is the Treatment of Heart Failure

• ACE inhibitors, Betablockers (Main 2 Key Drugs)

• Aldosterone Antanogists (Spironolactone or Eplerenone)

• Diuretics

• Ivabradine

Management of Complications i.e. Arrhythmia

Some Patients may benefit from Cardiac Resynchronisation Therapy.

List common ACE inhibitor Drugs

Ramipril Enalapril

List common Beta Blocker Drugs

Bisoprolol Metoprolol

How is Valvular Disease Diagnosed

Transthoracic Echocardiography

Although Transoesophageal Echocardiography gives better images particularly of the mitral valve but is not pleasant for the patient.

What are potential complications of Transoesophageal Echocardiography

Perforation of the Oesophagus

What is the treatment of Symptomatic Valvular Disease

Valve Surgery done by Cardiothoracic Surgeon

Valve Replacement with metallic prosthesis or biological prosthesis.

Metallic Valves need require lifelong medication unlike Biological Valves.

What medication are patients with metallic valves prescribed lifelong and why

Warfarin

Metallic Valves are seen more foreign so Red Blood Cells will get stuck on them therefore you require blood thinners to reduce the risk of clots around the valve.

What is the Treatment of Aortic Stenosis

Transcatheter Aortic Valve Implantation or Surgery.

How are Arrhythmias diagnosed

ECG at the time of Symptoms

What investigations can be done to find causes of Arrhythmias.

FIND THE CAUSES OF ARRHYTHMIAS

1. Echocardiogram for Heart Failure and Valve Disease

2. Angiogram for Coronary Artery Disease

3. Family Screening and Testing to see Genetic Conditions

What is the 12-Lead ECG used for?

Records the ECG in 12 different Angles to detect Arrhythmias

Where are the 12 Lead ECG Placed

1. Limb Leads (I, II and III)

2. Chest Leads (V1 - V6)

What does the P Wave Represent

Atrial Depolarisation

What does the QRS Complex Represent

Ventricular Depolarisation

What does the T Wave Represent

Ventricular Repolarisation

What does the ST Segment Represent

ventricular contraction and ejection

What does the PR segment represent?

depolarization of the AV node and its delay and depolarization of the Bundle of His and the Bundle Branches.

What does the QT interval represent?

ventricular depolarization and repolarization

A patient has an ECG taken. On their ECG the QRS complexes are very close together. What does this represent

A Faster Heart Rate

Generally what is the treatment for any Arrhythmia

Defibrillation

A patient has an ECG taken. You find the the QRS complexes are very wide apart. What does this mean

Slower Heart Rate

List 6 Types of Tachycardia

1. Atrial Fibrillation

2. Atrial Flutter

3. Supraventricular Tachycardia (SVT)

4. Ventricular Tachycardia

5. Ventricular Fibrillation

6. Ectopic Beats

What is the Treatment for Atrial Fibrillation and Atrial Flutter

1. Reduce the Heart Rate using Betablockers, Digoxin or Calcium Channel Blockers

2. Anticoagulate with Warfarin or DOACs if High Stroke Risk (Calculated by CHADS2-VASc score, any score above 1 given Anticoagulants)

How can you calculate if the patient has a high stroke risk

Calculate using the CHADS2-VASc score

Has the patient got Congestive Heart Failure, Have they got Hypotension, Are they over 65, are they Diabetic, have they had previous stoke, have they had previous vascular problem like Heart Attack, are they female (Females are higher risk of stroke)

Any Yes to these questions give a score of 1.

Then only is this patient given Anticoagulants.

What is the treatment for Supraventricular Tachycardia (SVT)

1. Attacks can be terminated by Vagal Manoeuvres

2. IV Adenosine

3. DC Cardioversion (Electric Shock)

4. Anti-Arrhythmic Drugs i.e. Beta Blockers or Flecainide to prevent further attacks from happening

What medications are patients who experience SVT prescribed to prevent further attacks occurring (3)

1. Beta Blockers

2. Flecainide

3. Amiodarone

What is the Treatment for Ventricular Fibrillation and Ventricular Tachycardia

1. Immediate DC Cardioversion (Electric Shock)

2. Prescription of Anti-Arrhythmic Drugs (Beta Blockers, Amiodarone)

3. Implantable Cardioverter Defibrillator under Skin with Lifelong Anti-Arrhythmic Drugs.

List Commonly used Anti-Arrhythmic Drugs

1. Beta Blockers

2. Amiodarone

3. Flecainide

How are Ectopic Beats Treated

1. Reassurance

2. Sometimes Betablockers.

Generally Never Require Treatment.

What is the treatment for Brady arrhythmia

Pacemaker Insertion

What does Dual Chamber Pacemakers treat

Treats Bradycardia

What do Implantable Cardioverters/Defibrillators treat

Tachycardias such as Ventricular Fibrillation and Ventricular Tachycardia

Can also Pace Bradycardias

What does Cardiac Resynchronisation Therapy (CRT) treat

Heart Failure

Can Also Pace Bradycardia (CRT-P) P for Pacing.

CRT-D (d for defib)

When should you refer Stable Angina

Stable Angina is not a reason to defer treatment, but increasing pain or pain at rest may well be. If the angina is frequent then Refer before you treat them as a Dentist.

When should you refer Stable Heart Failure

If the patient is breathless on exertion but can lie flat at night and is on medication, then DO NOT refer.

Increasing breathlessness or oedema may be.

Do not proceed treatment as a dentist as treatment may be worsening

A Patient has just had a recent MI. He/She comes to your dental practice. Are you able to treat them?

All Dental Appointments should be deferred until 3-6 months post an MI, longer is possible

Note the patient will be on DAPT for a year, followed by aspirin and have increased bleeding risk for at least a year or lifetime.

When should you refer patients with Tachycardia

Refer them until its properly assessed or treated.

If the patient is awaiting stents or bypass or valve surgery and are STABLE, can you as a dentist treat them?

Proceed with Treatment only if the patient is not getting worsening symptoms.

Why are Dentists often asked to improve patients Oral Hygiene and Dentition before Valves are replaced

To reduce the risk of getting Infective Endocarditis of the replacement valves.