Cardiovascular overview Flashcards
What are the components of the conductive system in the heart?
The sinus node –> Atrioventricular node –> Bundle of HIS –> Bundle Branches –> Purkinje fibres
What do the peaks and troughs of an ECG represent?
P - Depolarisation of both atria
Q - Excitation of the interventricular septum (beginning of ventricular depolarisation)
R - Spreading of excitation of right and left ventricular myocardium
S - Completion of ventricular depolarisation (Excitation of basal areas of the interventricular septum)
T - Rapid late repolarisation of ventricular myocardium
What are the 4 main causes of cardiovascular pathophysiology?
Electrical, Mechanical, Valve, and blood vessel dysfunction
What does high blood pressure do to blood vessels?
The increased shearing forces that high blood pressure puts on blood vessels damages the endothelium of blood vessels
What are 3 examples of electrical dysfunction?
Atrial fibrillation, Arrhythmia, Cardiac arrest
What are 4 examples of mechanical dysfunction?
Hypertension, Myocardial infarction, Cardiomyopathy, Heart failure
What are 3 examples of valve dysfunction?
Rheumatic fever, aortic stenosis, mitral regurgitation
What are 3 examples of blood vessel dysfunction?
Coronary artery disease, peripheral vascular disease, deep vein thrombosis
What are some risk factors for cardiovascular disease?
Diabetes
Smoking
Ageing
- decreased coronary artery blood
flow
- increased rigidity and thickening of valves
- Reduced number of myocytes
- Reduced amount of pacemaking and conduction tissues
Obesity
Sex
Dyslipidaemia
What is atrial fibrillation?
What causes it?
A common sustained arrhythmia, with incidence increasing with age
Can be caused by:
- Hypertension
- Valvular stenosis
- Ischemic heart disease
- Endocrine problems
- Infection
- Injury
What are some common symptoms of atrial fibrillation?
Fluttering, racing palpations
Shortness of breath
- Reduction of cardiac output
- Lightheadedness
What is considered new/paroxysmal atrial fibrillation?
Atrial fibrillation with symptom onset less than 48h old
Can new/paroxysmal atrial fibrillation be reverted to normal sinus rhythm?
Yes, with:
- DC cardioversion
- Restoration of optimal homeostasis (Oxygenation, perfusion, fluid and electrolyte balance)
- Antiarrhythmic medications
What is long-standing atrial fibrillation?
Atrial fibrillation which has existed for greater than 48h
Is shocking long-standing atrial fibrillation to revert it to normal sinus rhythm usually indicated?
No
