Cardio facts Flashcards
Define Hypoglycaemia
an abnormally low level of glucose in your blood
Define Hypoperfusion
a reduced amount of blood flow
Define Embolus
a blood clot which has been carried in the bloodstream to lodge in a vessel and cause an embolism
Define Thrombus
A blood clot that forms inside one of your veins or arteries
What is ischeamic?
a condition in which blood flow (and thus oxygen) is restricted or reduced in a part of the body
Define hypokalemia
Abnormally low levels of potassium in the bloodstream leading to tiredness
Define postural hypotension
a significant drop in blood pressure upon standing up from a lying or sitting position
Describe the difference between hypertension and hypotension
Hypertension is elevated blood pressure levels whereas hypotension is abnormally low blood pressure levels
Hypertension can cause > stroke, heart disease
Hypotension can cause > Dizziness, fatigue
Define Hypovoleamia
A decrease in the volume of blood circulating within the body.
Describe the simple difference between stable and unstable angina
Stable angina: This is the most common form of angina and occurs during exertion or stress. The pain usually subsides with rest or medication.
Unstable angina: This is a more serious form of angina that occurs suddenly and unpredictably, often at rest or with minimal exertion. It may signal an impending heart attack and requires prompt medical attention.
Define Patent ductus arteriosus
Ablood vessel called the ductus arteriosus, which connects the pulmonary artery to the aorta, fails to close after birth. This condition leads to a abnormal flow of blood between the aorta and the pulmonary artery
Define Tamponade
Fluid buildup around the heart causes pressure and impaired pumping. Treat by draining the fluid.
Define Tension pneumothorax
Air trapped in the chest cavity, compressing the lungs and heart. Treat by releasing the trapped air.
Define Thromboembolism
Blood clot traveling through the bloodstream, blocking blood flow. Treat with blood thinners to prevent further clotting.
What is radiofrequency ablation?
Selective cauterisation of cardiac tissue to prevent tachycardia involves using a procedure called radiofrequency ablation. This procedure targets specific areas of the heart where abnormal electrical signals originate or where they travel in a loop, called a reentry circuit, which can cause tachycardia (fast heart rate). By applying heat energy through a catheter to these targeted areas, the abnormal tissue is destroyed, preventing the abnormal electrical signals from causing tachycardia.
Difference between STEMI and NSTEMI
Both are complete blockages of the coronary arteries and both require medical attention.
STEMI - Shows ST elevation
NSTEMI - shows no elevation, maybe even deviation in ST segment
Both are treated with;
1. AntiPlatetes - asprin, P2Y12 inhibitors
2. Herparin
3. Morphine
What is White Coat Syndrome
Hypertension where blood pressure is only high in a clinical setting. Difference in 20/10mmHg when home and in a clinical setting
Verapamil blocks which type of ion channel and where is it located?
Verapamil blocks calcium ion channels and is primarily located in the heart and smooth muscle cells.
Statins work by blocking which enzyme from functioning?
Statins work by blocking the enzyme HMG-CoA reductase
How to work out Left ventricular Ejection fraction ?
stroke volume/ end diastlic LV volume x 100
How to calculate stroke volume?
difference between diastolic and systolic volume (end)
How to calculate cardiac output?
stroke volume x heart rate
How to calculate pulse pressure?
systolic pressure - diastolic pressure
Factors which increase pulse pressure
- Increased stroke volume
- a less compliant aorta
How to calculate Systemic Vascular Resistance ?
mean arterial pressure / cardiac putput
Examination reveals a significant drop in blood pressure, from 130/80 mmHg in a seated position to 100/60 mmHg standing, without notable ECG changes. This leads to the suspicion of a reflex dysfunction that is critical for blood pressure regulation.
What nerve is primarily responsible for the efferent pathway of this reflex? and why ?
The vagus nerve regulates the baroreceptor reflex, correcting an acute decrease in arterial blood pressure
What does preload mean?
end-diastolic voume
What does afterload mean?
aortic pressure
State Starlings law
Increase in end-diastolic volume will produce larger stroke volume
Explain barorecptor reflexes
They are located in the aortic arch and carotid sinus
Aortic baroreceptor impulses travel via the vagus and from the carotid via the glossopharyngeal nerve
They are stimulated by arterial stretch
Explain atrial stretch receptors
Located in the atria at the junction between pulmonary veins and vena cava.
Stimulated by atrial stretch and are thus low-pressure sensors.
Increased blood volume will cause increased parasympathetic activity.
Very rapid infusion of blood will result in an increase in heart rate mediated via atrial receptors: the Bainbridge reflex
What would increase after load?
ventricular dilation
What would increase preload?
Increased venous return
What would decrease after load?
Decreased systemic vascular resistance and hypotension
What would decrease Preload?
mitral valve stenosis
Difference between sinus, supraventricular and ventricular rythm
sinus - occurs in the SA node, right atrium
Supraventricular - above ventricles
Ventricular - in the ventricles
Difference between DC cardioversion and Radiofrequency ablation
DC cardioversion resets the heart’s rhythm through electrical shock, while radiofrequency ablation disrupts abnormal electrical pathways in the heart tissue to restore normal rhythm
What happens when troponin I is phosphorylated with regards to calcium action + action potentials?
Decreases affinity of troponin C for calcium, thus accelerating relaxation
ST elevation causes what
Infraction
Prolonged PR interval causes what?
Heart block
Delta waves cause what?
WPW syndrome
T wave inversion causes what?
Hypokalaemia
ST depression causes what?
Ischaemia
What measurement is the best predictor for cardiovascular risk?
Waist circumference
Hypokalemia ECG
ST depression
Flat/ Inverted T wave
U wave
Hyperkalemia ECG
Flat P wave
Prolonged PR interval
QRS widening
Tall, Peaked T wave
Upon initial examination, a newborn infant is having difficulty breathing and expanding the chest cavity. Follow-up imaging reveals agenesis of the central tendon of the diaphragm. Which of the following embryonic structures has failed to develop normally?
Septum transverse
A 65 year old man with a past medical history of ischaemic heart disease is brought into A&E reporting severe shortness of breath. He is diagnosed with pulmonary oedema.
Damage to which region of the heart is the most likely cause of this?
Left venticle
In aortic pressure tracings, an incisura or dicrotic notch is seen at the end of systole.
What is the cause of this dicrotic notch?
Closure aortic valve
The Frank-Starling curve of the heart shows one variable being proportional to another variable under normal physiological circumstances. What are the two variables that are linked via this curve?
Stroke Volume and Preload
A patient is admitted to the Emergency Department with a weak pulse, a rapid heartbeat and pale skin. It is thought that the patient is suffering from circulatory shock. Which condition is a cause of circulatory shock due to reduced venous return?
Haemorrhage
On the Frank-Starling curve, which variables are usually placed on the X-axis and Y-axis?
End-diastolic volume on X-axis, stroke volume on Y-axis
The ejection fraction is an important measure of heart function. What is the best approximation of the ejection fraction of a human under normal physiological circumstances?
60%
What is the correct definition of systolic blood pressure?
The maximum pressure reached in the arteries when the heart contracts
What is the main determinant of diastolic blood pressure?
Total peripheral resistance
Which valves are responsible for producing the first heart sound (S1)?
Atrioventricular (AV) valves closing
Which blood vessel carries deoxygenated blood into the right atrium?
VC
Which region of the heart does the pulmonary vein drain into?
Left atrium
During the cardiac cycle, what is the cause of the first heart sound?
An increase in ventricular pressure and a decrease in atrial pressure causes the atrioventricular valve to close
What is the earliest structurally apparent lesion in atherosclerosis?
fatty steak
During which phase of the cardiac cycle does the heart receive most of its own blood supply?
Diastole
Tom was exercising on his treadmill, and his heart rate was 90 beats per minute. His left ventricle pumped 6.3L of blood in 60 seconds. Given that the central venous pressure was negligible and that his total peripheral resistance is 20 (mmHg)(min)(mL-1), what was his mean arterial pressure?
Mean Arterial Pressure (MAP) = Cardiac Output (CO) x Total Peripheral Resistance (TPR). CO is 6.3L/min and TPR is 20mmHgmin/ml. Therefore, simply multiplying the CO by the TPR gives a MAP of 126mmHg
What is taken up by macrophages to develop foam cells?
LDL
What valve has 2 cusps?
mitral
Which blood vessel carries blood from the right ventricle to the lungs?
Pulmonary artery
Any male patients who score more than 0 and any female patients who score more than 1 on the CHA2DS2-VASc score should be prescribed what?
Anticogulation
What can cause prolonged QT interval?
macrolide antibiotic - Azithromycin, clarithromycin, and erythromycin
Down syndrome’s most common cause is what mutation?
Nondisjunction mutation
