Cardiology Flashcards
What are the 3 main components of blood, what do they contain, and what percent of blood does each make up?
- Plasma = top layer
contains proteins, water and nutrients
Makes up 55% of blood - Buffy coat = middle layer
Contains white blood cells and platelets
Makes up 1% of blood - Erythrocytes = bottom layer
Contains red blood cells
Makes up 45% of blood
What is the epicardium?
What is the pericardium?
Epicardium = muscly protective layer of the heart, needs its own blood supply
Pericardium = contains fluid to lubricate the heart (see diagram of heart in jotter)
What is the superior and the inferior vena cava, and where are they located (include if they carry oxygenated or deoxygenated blood)?
Both bring deoxygenated blood from the body to the left side of the heart (to the right atrium - remember opposite of what you think)
Superior = brings blood from the upper parts of the body to the heart
Inferior = brings blood from the lower body
Where is the Pulmonary artery, Aorta, and pulmonary vein located? (include if they carry oxygenated or deoxygenated blood)
- Pulmonary artery = Artery carrying deoxygenated blood from the right ventricle to lungs (from LHS)
- Aorta = Artery carrying oxygenated blood from the left ventricle to the rest of the body (from RHS)
- Pulmonary vein = Vein carrying oxygenated blood from the lungs to the left atrium (to RHS)
Where are the tricuspid and bicuspid valves located?
Where is the septum and pericardium located?
Tricuspid = valve between right atrium and ventricle (LHS)
Bicuspid = valve between left atrium and ventricle (RHS)
Septum = muscly part of heart (middle, in between the 2 ventricles, see diagram)
Pericardium = loops around the periphery of the heart (around the edge)
What is the pathway for electrical impulses received by the heart (general pathway)? (3) (include where each receiver is located in the heart)
- Impulses received at the SAN, located at top of right atrium
- Impulses passed on from SAN to AVN, which is found at the lower right atrium
- Impulse then travels down a bundle of His, located at the septum (middle) of the heart
- The impulses then travel through the purkinje fibres, which flow up the sides of both the ventricles, causing the heart to contract and beat
What 2 systems does the autonomic nervous system include, and what do they do?
What part of the brain controls the autonomic nervous system?
Sympathetic nervous system = Fight or flight
Parasympathetic = Rest and digest
Medulla
What is the pathway of parasympathetic nervous systems from the brain to heart, including what neurotransmitter is transported?
What is the pathway of sympathetic nervous systems from the brain to heart, including what neurotransmitter is transported?
From medulla, down the vagus nerve to the SAN and AVN nodes in the right atrium in the heart. Transports acetylcholine.
From medulla, down the thoracic spinal chord in the spine, then travels down the sympathetic ganglia nerves to the SAN + AVN nodes as well as the purkinje fibres. Transports noradrenaline (noradrenaline can also come from the kidneys as well)
See diagram in jotter
What are the 5 waves of the ECG and what do they mean + what do they mean in terms of heart contraction/relaxation? (in order, in alphabetical order)
- P wave = Atrial depolarisation - valves between the atria and ventricles contract (open) to allow blood to flow from the atria into the ventricles (signal passed from SAN to AVN) (Atrial contraction)
- Q wave = Depolarisation of the septum - electrical signal passed down bundle of His, depolarising the septum from left to right
- R wave = Ventricular depolarisation - electrical stimulus is being passed through the main portion of the thick ventricular walls
- S wave = depolarisation of the purkinje fibres
QRS wave represents the ventricles contracting - T wave = ventricle repolarisation - ventricles relaxing
What is sinus Arrhythmia?
What is sinus Bradycardia?
What is sinus Tachycardia?
Arrhythmia = irregular heartbeats
Bradycardia = decreased heart rate (less ECG peaks)
Tachycardia = increased heart rate (more ECG peaks)
What are baroreceptors and chemoreceptors? (basic of what they do)
Baroreceptors = detect changes in blood pressure
Chemoreceptors = detects chemical level changes
Both control homeostasis of these things
What is the heart rate pulse and how exactly is it generated?
Where is the throbbing sensation felt? (2 artery names and locations)
Rhythmic expansion and contraction of arteries as blood is ejected from the heart during each heartbeat
Generated by a blood surge in the left ventricle
Felt in the radial artery in the wrist or the carotid artery in the neck
What is systolic and diastolic blood pressure?
Systolic = pressure when ventricles are pumping blood out of the heart (contracting)
Pressure is highest on arteries during this time
Diastolic = pressure on arteries between heartbeats, when heart is resting and filling up with blood
Pressure is lowest on arteries during this time
What is the normal range for resting heart rate?
What is the normal blood pressure?
60-100bpm
120/80 mmHg or less
What is VO2 and what is VO2 max?
What are the units of VO2 max, and what is the normal resting oxygen consumption (VO2)?
What is VO2 max a useful indicator for?
VO2 = how well oxygen can be delivered to tissues during exercise
VO2 max = maximum rate of oxygen your body can use during exercise
Units = ml/kg/min
Resting oxygen consumption = 9ml/100g/min
VO2 max is a useful indicator of cardiovascular fitness and aerobic endurance
What are the 3 main CVDs and what are the modifiable (6) and non-modifiable (4) risk factors of them?
What do most treatments focus on in general for CVDs? (3)
Coronary artery disease, hypertension, and arrhythmias
Modifiable = high blood pressure/cholesterol, smoking, diabetes, physical activity, diet
Non-modifiable = Age, gender, family history, and genetics
Treatments focus on relieving cardiac workload by removing blood clots, decreasing heart rate + blood pressure, and opening up blood vessels
What are the treatments 4 main treatments for coronary artery disease and what do they all do? (not lifestyle modifications)
- Medications like antiplatelet agents to prevent blood clots (aspirin)
- Beta-blockers to decrease heart heart rate and blood pressure
- Revascularisation to open narrowed or blocked arteries
- Coronary artery bypass grafting to create new blood flow routes around blocked arteries
What are the treatments 5 main treatments for hypertension and what do they all do? (not lifestyle modifications)
- Diuretics to reduce fluid volume and reduce blood pressure
- ACE inhibitors, beta-blockers, calcium channel blockers, and antihypertension drugs to relax blood vessels and reduce blood pressure
What are the treatments 5 main treatments for Arrhythmias and what do they all do? (not lifestyle modifications)
- Medications
- Pacemakers + implantable cardiovascular defibrillators = implantable devices
- Medical procedures - cardioversion + ablation therapy
What is the definition of hypertension? (incl. values)
What does exercise do to blood pressure in the short term and long term?
How is blood pressure different in men and women?
Sustained high blood pressure:
Systolic > 140mmHg
Diastolic > 90mmHg
Increases blood pressure temporarily
Lowers resting blood pressure (and heart rate)
Women have lower blood pressure until they reach menopause, and then it’s around the same for men and women
What 3 diseases is hypertension a risk factor for? (just names)
- CVDs
- Kidney disease
- cerebrovascular diseases = conditions that affect blood flow to the brain (e.g. strokes)
What is the equation for blood pressure, including units of each part?
Blood pressure = CO x TPR
Where CO = Cardiac output (volume of blood pumped out by each ventricle per min) - l/min
TPR = Total Peripheral Resistance (diameter of arteries) - mmHg/ (l/min)
CO = Stroke volume x Heart Rate
SV = Volume of blood pumped out by each ventricle every heart beat - l
HR = bpm
How do the kidneys regulate blood pressure and how is this related to salt concentration?
What is rapid blood pressure controlled by?
What is long-term blood pressure controlled by?
What is blood volume and salt/water balance a risk factor for?
Kidneys control how much water and salt we pee out, which controls the level of how much water and salt are in the body. This controls how much blood is in the body (Blood volume) which control blood pressure.
Short-term = heart rate and TPR
Long-term = blood volume (by the kidneys)
Hypertension risk factors
Which 2 hormones in the kidneys control salt/water concentration and where is each found within the kidney?
Roughly how much of the body is made of water?
- Aldosterone = secreted by the adrenal gland, controls salt concentration
- Vasopressin = controls volume of water (just secreted by general kidneys)
50% of the human body is made of water
