Dr. Zachow - 12/14

Question 1

WHat are some possible area of damage due to RAAS?

Answer 1

LVH - leads to increased wall stress and O2 demand. Will have reduced ejection fraction.
Carotid Stenosis
Kidney Damage

Question 2

What drugs can you use to manage HTN?

Answer 2

Beta Blockers
Alpha2 agonists
Alpha1 antagonists
HCTZ (diuretic)
ACE inhibitors 
Calcium channel blockers
ARB
Aldosterone antagonists

Question 3

Match the drug name with the type of drug it is:

Losartan, HCTZ, amlodipine, verapamil, atenolol, enalapril

Answer 3

Losartan - ARB (angiotensin receptor blocker)
HCTZ - diuretic (thiazides)
Amlodipine - calcium channel antagonist
Verapamil - Ca2+ antagonists
Atenolol - beta blocker
Enalapril - ACE inhibitor (impede production of angiotensin II)

Question 4

Secondary Hypertension

Answer 4

USually involved with some sort of pathological disorder that can usually be identified and potentially fixed. Often brought on due to renal disease, endocrine disease, drugs, meds, alcohol. Even after taking 3 meds the HTN will not subside. Abrupt onset.

Question 5

TPR =

Answer 5

TPR = (Pa-Pv)/Qt

Qt is total flow

Question 6

At what point is there the greatest drop in pressure?

Answer 6

Across the arterioles. This is because they are full of smooth muscle so they can expand.

Question 7

What part of flow is considered capacitance? Exchange? Resistance?

Answer 7

Resistance: aorta –> artery –> arteriole –>
Exchange: Capillary
Capacitance: Venules –> Veins –> Vena cava

Question 8

WHat two things can happen to Ensure that flow through the capillaries is constant and with a norma Pressure?

Answer 8

deltaP = Q x R

It change change pressure in the arteriole or resistance in the arteriole by changing sphincteric diameter.

Question 9

Pcap
Pif
PiCap
PiIf

Answer 9

Pcap - pressure of the blood pushing out onto the walls of the capillaries.
Pif = small amount of pressure pushing onto the wall of the capillary trying to come inside.
PiCap = oncotic pressure of the plasma in the capillary that is attracted to the albumin in the capillary, causing it to stay in the capillary.
PiIf = oncotic pressure in the interstitium that wants to bring water out of the capillary

Question 10

How is edema caused?

Answer 10

1) increased arterial pressure
2) increased capillary permeability
3) Decreased venous return
4) compromised lymphatic function

Question 11

Mechanisms of action regulating vasodilation in VSM

Answer 11

1) epinephrine (low concentration)
2) vasodilatory factors - CO2, H+, lactic acid, histamine, thrombin, and prostaglandins.
- Basically the target is cGMP an PKG. All of the previous things hit their respective receptors, which activate eNOS (epithelial nitric oxide synthase), and eventually makes PKG and cGMP. PKG inactivated type L calcium channels, which will impede inward calcium movement So that there is relaxation. PKG also activates SERCA, which sequesters calcium and causes relaxation.

Question 12

Mechanisms promoting vasoconstriction in VSM

Answer 12

PKC is the key here. Epinephrine in high concentrations, will eventually, downstream, activate PKC. Once PKC is activated it will activate type L calcium channels and cause increased calcium flow and therefore vasoconstriction. It will also inactivate SERCA through aracodonic acid and PGF2alpha so that there will be no sequestration of calcium and therefore there will be vasoconstriction.

Question 13

Explain what occurs in a sick left heart (systolic heart failure)

Answer 13

In a sick left heart the left ventricle will be unable to pump out proper amounts of blood. Because of this, the ejection fraction will increase and there will be more blood left in the left ventricle. This will cause an increase in pressure, which will cause an increase in pressure in the left atrium. This will then cause an increase in pressure in the pulmonary system and then the right ventricle will be unable to empty proper and eventually pressure will build up all the way back at the right atrium.

Question 14

Explain what occurs in right Sick heart

Answer 14

Increased right ventricular pressure will have all. Of the normal. Pathologies that we would expect in addition to hepatic portal hypertension, pulmonary HTN, and jugular vein distention. This is because this is where the IVC, SVC, and pulmonary trun.

Question 15

When is there greater blood flow to the coronary arteries, diastole or systole?

Answer 15

Diastole, there is also maximal O2 uptake here.

Question 16

How will a reduced coronary artery diameter exponentially diminish flow?

Answer 16

With reduced coronary artery diameter you will see reduced O2 delivery because there is less blood getting through. Once this happens, more ADP and AMP are made and is cleaved into adenosine. Once this happens, vasoconstriction occurs so we see even less flow.

Question 17

What does alpha2 do?

In the coronary arteries are there a lot of them?

Answer 17

It is a vasoconstricter, just like Alpha1. The reason we saw alpha2 agonists as vasodilatory earlier is because it acted on the SNS to decrease SNS tone.
There are a lot of them in the coronary arteries, which cause vasoconstriction.

Question 18

What are the 3 things that require the most oxygen in the heart in order?

Answer 18

1) ventricular wall stress 2) heart rate 3) contractility

Question 19

What are the affects of cardiac ischemia?

Answer 19

There will be an impedement of blood flow, which will cause localized anemia, decreased local O2, decreased left ventricular function, and then increased left ventricular pressure. This will cause two things to occur:

1) it will increase left atrial pressure –> increase pressure in the lungs –> cause dyspnea (increased breathing rate and force)
2) increased wall stress will cause increased O2 demand, which will rev up the SNS, which will cause HR contractility.

Question 20

What are the two reasons for cardiac ischemia

Answer 20

1) atherosclerotic plaques

2) endothelial/VSM dysfunction

Question 21

What would an EKG of cardiac ischemia look like?

Answer 21

On the side with the ischemia:

1) inverted or flattened T waves
2) Horizontal or down sloping ST depression

Question 22

Symptoms of angina

Answer 22

Exertion all onset, diffuse retrosternal pressure/tightness that resolves on rest

Question 23

Why does ischemia cause chest pain?

Answer 23

Because hypoxia will begin to occur, which produces lactate. Normally lactate is a good thing but too Mach can cause detrimental affects on the production of ATP, which will cause adenosine to be created, which will ruin the integrity of the sarcolemma causing adenosine and other compounds to be dumped out of the myocardium. These things will bind to nociceptors.

Question 24

Why will angina caus SOB, tachacrdia, and diaphoresis?

Answer 24

Hypoxia will impair left ventricle function, causing increased left ventricular pressure and then back into the cycle we keep seeing in that if affects the lungs and the cycle of increased wall stress.

Question 25

How do you treat angina medically?

Answer 25

Beta blockers, calcium channel blockers, nitroglycerine, nitrous oxide.

Question 26

Renin
Angiotensin II
Aldosterone

Answer 26

Renin - causes angiotensin II synthesis
Angiotensin II - vasoconstricter that causes aldosterone release from the adrenal cortex.
Aldosterone - Causes Na+ conservation in the kidneys, which causes us to hold on to water.

Question 27

When your heart Is failing, What energy source will the heart be using?

Answer 27

Glucose. Normal hearts use FFA.