Ischaemic heart disease

Question 1

What is ischemia?

Answer 1

Ischemia: is a restriction in blood supply to tissues, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive)

Question 2

What are risk factors for ischemia?

Answer 2

• Hyperlipidemia
• Diabetes
• Obesity
• Smoking
• Genetics

Question 3

What are the consequences of ischaemic heart disease?

Answer 3

• Stable angina: coronary artery (surrounds heart) narrowing. Occurs when there is a high 02 demand (exertion only), and the pain is relieved with rest.
• Unstable angina: serve coronary artery narrowing with chest pain that isn’t relived with rest. Occurs at any time
• These can eventually lead to myocardial infraction and death

Question 4

Describe the cardiac conductiive system

Answer 4

• Thesinoatrial (SA) nodeis a collection of specialised cells (pacemaker cells), and is located in the upper wall of the right atrium, at the junction where the superior vena cava enters
  
  • When this generates an impulse, it results in atrial contraction
  • After the electrical impulses spread across the atria, they converge at theatrioventricular node. The wave of excitation then passes from the atrioventricular node into the atrioventricular bundle
  • Theatrioventricular bundle(bundle of His)transmits the electrical impulse from the AV node to the Purkinje fibres of the ventricles

Question 5

Describe cardiac markers used to diagnose myocardial infarction

Answer 5

• Cardiac markersare biomarkersmeasured to evaluate heart function

Creatine Kinases
• Is a protein that helps with muscle cell function. CK-MB is associated with heart muscle damage
• Elevation period: 12- 48 hrs

Troponin:
• Are a group of proteins that regulate muscular contraction of the heart by binding to myofilaments.
• Elevation period: 10-14 days