L19 - Heart Blocks and Heart Failure

Question 1

What are heart blocks?

Answer 1

• disruption to the conduction of electrical signal through the heart.
• Make up majority of cardiac arrhythmias.

Question 2

What are partial blocks?

Answer 2

• A delay of the electrical impulses or they move slower than usual.
• Causes innapropriate depolarisation, slowing conduction.
• Can be caused by tissue injury or stretch.

Question 3

What is a complete block?

Answer 3

• When the electrical signals stop completely.
• Abnormal Anatomy
• Extra conduction pathway

Question 4

What are the 3 types of partial block?

Answer 4

Slowed conduction, intermittent block, unidirectional block.

Question 5

Slowed Conduction (Partial)

Answer 5

• All signals conducted but conduction is slower.
• Slower through the AV node = longer PE
  interval.

Question 6

Intermittent Block (Partial)

Answer 6

• only some signals conducted.
• second degree AV block
• mobitz type I&II

Question 7

What is a mobitz type 1 block?

Answer 7

• When each cycle of the PR interval increases till eventually the AV node fails.
• Can result in a Bundle branch block.

Question 8

What is a mobitz type 2 block?

Answer 8

The PR interval is constan every nth ventricular depolarisation is missing

Question 9

Unidirectional Block (Partial)

Answer 9

• Causes inappropriate pacemaker activity.
• Can be caused by things like dead cells.
• New pacemaker can form, causing atrial &
  ventricular tachycardia, fibrillation plus
  other arrhythmias.

Question 10

Unidirectional Block (Complete)

Answer 10

• 3rd degree AV block.
• electrical severing of the atria and the
  ventricles, causing their own pacemakers
  to dominate.

Question 11

What is Wolff Parkinson White (WPW) Syndrome?

Answer 11

A heart condition that causes the heart to beat abnormally fast for periods of time.

Question 12

What is the main cause of WPW syndrome?

Answer 12

An additional accesory pathway from atria to ventricles (Bundle of Kent)

Question 13

Some characteristics of WPW syndrome?

Answer 13

• AV delay lost
• Ventricular depolarisation spread out
• Shorter interval at P to QRS
• Atrial tachychardia

Question 14

What is heart failure?

Answer 14

• A condition where the heart struggles to maintain an approprite cardiac output.
• Also assosiated with a drop in EF (ejection
  fraction).

Question 15

What are some of the causes of heart disease?

Answer 15

• Diabetes
• Hypertension
• Infections
• Cardiomyopathies
• Toxins
• Prolonged Arrytmias

Question 16

What are some symptoms of heart failure?

Answer 16

• Dyspnea
• Cough/Wheezing
• Fluid in the abdomen due to poor venous
  return
• Fatigue
• Palpitations
• Oedema of the lower extremeties