Cardio Lectures

Question 1

Define hypertension

Answer 1

A chronic elevation in blood pressure, grade 1 hypertension is classified at 140-159 Systolic and 90-99 Diastolic

Question 2

What is the systolic and diastolic of grade 1 hypertension

Answer 2

Grade 1 = Systolic of 140-159 and Diastolic of 90-99

Question 3

What is the systolic and diastolic of grade 2 hypertension

Answer 3

Grade 2 = Systolic of 160-179 and Diastolic of 100-109

Question 4

What is the systolic and diastolic of grade 3 hypertension

Answer 4

Grade 3 = Systolic of >180 and Diastolic of >110

Question 5

What are some of the consequences of hypertension

Answer 5

Left Ventricular Hypertrophy, Stroke/MI, Renal failure and Retinal damage

Question 6

What is the short term mechanism of blood pressure regulation?

Answer 6

Short-term regulation of blood pressure is controlled by the sympathetic nervous system (SNS). Changes in blood pressure are detected by baroreceptors. These are located in the arch of the aorta and the carotid sinus. Increased arterial pressure stretches the wall of the blood vessel, triggering the baroreceptors.

Question 7

Explain the renin-angiotensin aldosterone system

Answer 7

1. When your blood pressure falls, your kidneys release the enzyme renin into your bloodstream.
2. Renin splits angiotensinogen, a protein your liver makes and releases, into pieces. One piece is the hormone angiotensin I.
3. Angiotensin I, which is inactive (doesn’t cause any effects), flows through your bloodstream and is split into pieces by angiotensin-converting enzyme (ACE) in your lungs and kidneys. One of those pieces is angiotensin II, an active hormone.
4. Angiotensin II causes the muscular walls of small arteries (arterioles) to constrict (narrow), which increases blood pressure. Angiotensin II also triggers your adrenal glands to release aldosterone and your pituitary gland to release antidiuretic hormone (ADH, or vasopressin).
5. Together, aldosterone and ADH cause your kidneys to retain sodium. Aldosterone also causes your kidneys to release (excrete) potassium through your urine.
   The increase in sodium in your bloodstream causes water retention.
6. This increases blood volume and blood pressure, thus completing the renin-angiotensin-aldosterone system.

Question 8

What is aldosterone, what does it bind to and what does it increase

Answer 8

Aldosterone is a steroid hormone that binds to the mineralocorticoid receptor and increases the transcription of ENaC and Na-K pumps in the tubule epithelia. This causes increases in Na+ reabsorption and K+ secretion

Question 9

Define heart failure

Answer 9

Heart failure is a chronic progressive condition. Through abnormality of cardiac structure or function and systemic changes that lead to a failure of the heart to fill and/or eject blood. This then leads to a failure to deliver oxygen at a rate that is required of the metabolizing tissues

Question 10

What are the two types of heart failure

Answer 10

Heart Failure with Preserved Ejection Fraction (HFpEF) and Heart Failure with Reduced Ejection Fraction (HFrEF)

Question 11

In HFrEF what happens to Left Ventricular volumes and Ejection Fraction

Answer 11

When HFrEF occurs, Left Ventricular Volumes increase, and the Ejection Fraction decreases

Question 12

What is Systolic Heart Failure and Diastolic Heart Failure

Answer 12

Systolic Heart Failure = HFrEF
Diastolic Heart Failure = HFpEF

Question 13

What are some of the Pharmacotherapies for heart failure

Answer 13

ACE inhibitors, ARBs, Beta Blockers, Diuretics

Question 14

What is VAD

Answer 14

VAD stands for Ventricular Assist Device

Question 15

Define heart failure, briefly explaining and contrasting HFpEF and HFrEF

Answer 15

Heart failure is a chronic progressive condition. Through abnormality of cardiac structure or function and systemic changes that lead to a failure of the heart to fill and/or eject blood. This then leads to a failure to deliver oxygen at a rate that is required of the metabolizing tissues
HFpEF = Heart failure with preserved ejection fraction is also known as diastolic heart failure, where the wall are thickened and stiff causing the heart to struggle to fill
HFrEF = heart failure reduced ejection fraction known as systolic heart failure, where the walls are thin and dilated causing the heart to struggle to pump

Question 16

Current end-stage therapies used to manage heart failure involve heart transplantation and ventricular assistance devices (VADs). Explain their major disadvantages (3 marks) and then elaborate on how cardiac stem cell research may allow cardiac regeneration as a future therapeutic option (2 marks).

Answer 16

1. The current major disadvantages of VADs are, costs, longevity, bleeding, and infections
2. Cardiac stem cells may be the future option such as the use of Neuregulin and reprogramming non-myocytes. This new research focuses on the regeneration and restoration of the function of the heart after injury.

Question 17

In an ECG what is ST segment elevation a sign of

Answer 17

an area of ischemia has developed less than an hour ago

Question 18

When is the best time to initiate hormone replacement therapy to prevent against cardiovascular disease

Answer 18

within the first 10 years

Question 19

your access to and level of healthcare and longevity is primarily related to

Answer 19

the affluence of the country you live in

Question 20

what is the measurement that is derived from tissue Doppler of the mitral annulus

Answer 20

E/A ratio

Question 21

What measures the amount of blood moving from the left atrium to the left ventricle in diastole

Answer 21

E/A ratio

Question 22

Describe the different waves of the ECG trace, link them to the changes in membrane potential of cardiac cells and the physical changes of the heart?

Answer 22

P-wave: atrial depolarisation
QRS: ventricular depolarisation
T: ventricular repolarisation

Question 23

Describe the role of cavin/caveolin/eNOS and nitric oxide in regulating cardiac stiffness

Answer 23

Cavin and caveolin proteins were reduced in old people
Cavin knockout mice have reduced caveolin activity
Cavin and caveolin proteins regulate cardiac stiffness
Caveolae (membrane mechanosensors and invaginations in membrane, when you stretch a cell, you flatten the caveolae which ejects proteins and phosphorylates caveolin 1 which inhibits NOS activity) formation and function is dependent on cavin and cavolae proteins

Question 24

Describe the history of research into the cardiovascular effects of hormone replacement therapy.
What were the initial published conclusions and how was our understanding refined over time.
What are the current recommendations?

Answer 24

Estrogen = cardioprotective
· Clinical trial prematurely ended due to ↑breast cancer risk and ↑CHD risk
· Didn’t account for the time between menopause and HRT commencement
· Findings: if HRT is started within 10 years of menopause onset = reduce risk.

Question 25

What does the T-wave of an ECG trace represent? Why is the T wave positive?

Answer 25

Ventricular repolarisation . Although repolarisation occurs in the opposite direction to depolarisation, the wave is positive. This is because the impulse is traveling from the positive to the negative end, but it is traveling away from the electrode. Therefore, two negatives make a positive.

Question 27

As the blood levels the left ventricle it moves through the a number of vessel types before it reaches the right atria? Provide the correct order of the vessels blood moves through

Answer 27

Aorta-Arteries-Arterioles-Capillaries-Venules-Veins-Vena Cava- Right Atrium

Question 28

Describe the four New York Heart Association Functional Classifications of heart failure

Answer 28

1. Asymptomatic HF: Previous MI, LV dysfunction, Asymptomatic valvular disease
2. Symptomatic HF: known structural heart disease, shortness of breath and fatigue, reduced exercise tolerance
4. Refractory End-Stage HF: