Heart and cardiovascular system Flashcards
What is the pulmonary circulation?
Carries blood to and from the lungs to exchange carbon dioxide for oxygen
What is the systemic circulation?
Carries blood to the rest of the body
Is blood transported/returned via arteries or veins?
Transported via arteries and returned via veins
What is the microcirculation?
Where things enter and leave the cardiovascular system- water oxygen, co2, nutrients and waste products
Where do arteries carry blood away from?
The heart
Where do arterioles carry blood to?
Capillaries
What is the cardiac cycle?
The sequence of depolarisation and repolarisation of cardiac muscle giving rise to an electrical cycle of activity in the atria and ventricles
What is the primary cause of coronary artery disease?
Atherosclerosis
What are the non modifiable risk factors for atherosclerosis?
Age, gender, family history, ethnicity (50% more likely for south asians)
What are the modifiable risk factors for atherosclerosis?
Dyslipidaemia, diet, alcohol hypertension, T2D, smoking, inactivity, medications and recreational drug use
What is atherosclerosis?
Formed by atheroma- fatty plaque formed on the inside of blood vessels, artery walls can become narrowed, less blood is delivered
What is cholesterol?
A lipid molecule, synthesised by animal cells, essential for life as allows cells to survive without a cell wall and helps synthesis of vitamin D, steroid hormones and formation of bile acids
Where is cholesterol mostly synthesised?
The liver
What is ‘good’ cholesterol?
HDL- transfers fats away from cells towards the liver
What do statins do?
Lower hepatic synthesis of cholesterol, more clearance of LDL which means better ratio between HDL and LDL
What are the potential side effects of statins?
Hepatoxicity
What are the other options of treating atherosclerosis?
-Ezetimibe- lower absorption of cholesterol
-Bile acid sequestrants- use up more cholesterol from making more bile acids
-Nicotinic acid- lipase inhibitor
-fibrates- higher lipolysis
-surgical treatment
What are some of the consequences of atherosclerosis?
Stroke, heart failure, MI (heart attack), angina, hypertension, aneurism, peripheral vascular disease
What is a CT angiogram?
A type of medical test that combines a CT scan with an injection of a special dye to produce pictures of blood vessels and tissues in a part of your body. Can map all coronary blood vessels.
What could you see on a CT angiogram?
All blood vessels- blockages, tissue density, good to use before surgery
What is a cardiac MRI good for?
Can see if a part of the muscle is contracting properly, can find areas that are white- MI
What is haemolytic anaemia?
High blood pressure causing blood vessels to become turbulent. Causes lower red blood cells.
How do you treat hypertension?
-increasing excretion of sodium and water by diuretics
-reducing production of angiotension II by ACE inhibitor
-slowing heart rate, force of contraction and TPR- beta blockers
What is angina?
Chest strangle feeling due to coronary artery disease
What is unstable vs stable angina?
-Stable- only at exercise or movement
-unstable- while at rest
When might you see silent angina?
Diabetic patients
What is the pharmaceutical management of angina?
-Nitrates eg GTN spray
-Beta blockers
-Calcium channel blockers
-Anti-platelet drugs
What is the surgical management of atherosclerosis/angina?
-Coronary artery bypass grafting
-Percutaneous coronary intervention- stent using balloon in radial artery that holds artery open
What are the signs of heart failure?
Swollen ankles, peripheral cyanosis, SOB
