L16

Question 1

What does the P wave represent?

Answer 1

Atrial depol

Question 2

What does the QRS represent?

Answer 2

Ventricular depol

Question 3

What does the T wave represent?

Answer 3

Ventricular repol

Question 4

What does the QT interval represent?

Answer 4

Length of ventricular cycle

Question 5

How does the sympathetic NS respond to heart failure (↓CO)?

Answer 5

Sympathetic

• Vasoconstriction = ↑afterload
• Na/H2O retention = ↑BV
• LV remodeling

Question 6

Which substances naturally oppose vasoconstriction and Na retention to counter regulate maladaptive processes?

Answer 6

Natriuretic peptides

PGs

Question 7

What is the difference between short and long term adaptations/compensation for ↓CO?

Answer 7

Short = adaptive changes
Long = maladaptive

Question 8

Which vasoactive peptides are released due to heart failure?

Answer 8

RAAS
Natiuretic peptides
ADH
Endothelins

Question 9

What inflammatory mediators are released due to heart failure?

Answer 9

PGs

Question 10

What type of HF are RAS inhibitors and BB really beneficial for?

Answer 10

HR w/ ↓EF

Question 11

What are the 3 triggers that ↑renin release during HF?

Answer 11

↓Pre-glomerular BP
↓NaCl @ macula densa
↑NE from sympa at B1 receptors

Question 12

What is ACE2? Same as ACE?

Answer 12

ACE = Angiotensin converting enzyme, AGT1 –> AGT2
ACE2 = counters adverse cardiac effects of excess AGT2
- Vasodilation
- Antiproliferative

Question 13

3 ACE inhibitors

Answer 13

Captopril
Enalapril
Linospril

Question 14

2 angiotensin receptor blockers

Answer 14

Losartan

Valsartan

Question 15

Renin inhibitor

Answer 15

Aliskiren

Question 16

How does AGT 2 change TPR when binding AT1 receptors? Net response?

Answer 16

↑vasoconstriction
↑Sympa
Net = rapid ↑BP

Question 17

How does AGT2 change renal fxn when binding AT1 receptors? Net response?

Answer 17

↑Na reabsorption
- Directly
- Indirectly via ↑aldosterone
Net = slow ↑BP (volume expansion)

Question 18

How does AGT2 change CV structure when binding AGT1 receptors? Net response?

Answer 18

↑proto-oncogenes
↑GF
↑Afterload 
↑Wall tension
Net = LV hypertrophy/remodeling

Question 19

What explains part of ↓BP of ACE inhibitors?

Answer 19

↑Bradykinin & PGs

Turning off ACE also turns off the enzymes that inactivates bradykinin

Question 20

Bradykinin fxn

Answer 20

Vasodilator

↑PG synthesis

Question 21

Adverse effects of ↑bradykinin/PGs due to ACE inhibitors

Answer 21

Dry cough

Angioedema

Question 22

Captopril

• Excretion
• Dosing

Answer 22

Renal excretion - impt for pts w/ HF

Low doses to avoid SEs

Question 23

Captopril SE (usually seen at high doses)

Answer 23

Disrupt taste
Skin rashes
Nephropathy
Neutropenia

Question 24

Enalapril & fosinopril

- Excretion

Answer 24

Both = longer t1/2 than captopril 
Enalapril = renal excretion
Fosinopril = renal and bile excretion

Question 25

Changes in plasma levels due to ACE inhibitors - Renin - AGT1 - AGT2 - Aldosterone

Answer 25

↓AGT2 & aldosterone - Both downstream of ACE action ↑renin --> ↑AGT1 b/c no - FB - Doesn't matter b/c ↑AGT1 can't be converted

Question 26

Aldosterone fxn

Answer 26

↑Na & H2O reabsorption in collecting duct | K wasting

Question 27

2 mineralcorticoid receptor antagonists

Answer 27

X aldosterone binding Spironolactone Eplerenone

Question 28

Effects of binding AT2 receptors (not AT1)

Answer 28

``` Counter reg to AT1: Vasodilation Antiprolif Differentiation Plaque rupture ```

Question 29

When do you see AT2 receptors ↑regulated?

Answer 29

Failing heart! | Natural counter reg against AGT1

Question 30

Which drug is AT1 selective?

Answer 30

Angiotensin receptor blockers | Big deal b/c the AGT2 produced by feedback acts selectively on AT2 receptors = beneficial!

Question 31

Which drug changes AT1 & AT2 receptor activity?

Answer 31

ACE inhibitors | ↓total AGT2 so can't work on either receptor

Question 32

Plasma levels of these on ARBs - Renin - AGT1 - AGT2 - Aldosterone

Answer 32

↓Aldosterone | ↑renin, AGT 1 & 2

Question 33

``` Plasma level on renin inhibitors of Renin AGT1 AGT2 Aldosterone ```

Answer 33

↓all

Question 34

What is one of the biggest shared benefits of ACE, renin inhibitors, and ARBs?

Answer 34

INHIBIT vascular hyperplasia Regress existing LVH!!! Preserve renal fxn

Question 35

Shared adverse effects of ACE inhib, renin inhib, ARBs?

Answer 35

Hyperkalemia --> arrhythmia Renal failure if you have renal artery stenosis Teratogenic - don't give to women of childbearing age

Question 36

What change is significant to pts with renal artery stenosis?

Answer 36

Any ↓AGT2 | That is what is constricting the efferent arteriole of the glomerulus to maintain GFR

Question 37

What is measure to determine natriuretic peptide levels?

Answer 37

Cleavage product in plasma that has longer t1/2 = BNP ↑BNP = ↑HF level

Question 38

Effects of natiuretic peptide - Renal - Vasc - Cardiac - SNS

Answer 38

Renal: ↓Na resorption Vasc: vasodilation Cardiac: ↑rate relaxation, antiproliferative SNS: ↓SNS & renin release