CV-Renal

Question 1

What is the basis of Hypertension?

Answer 1

Hypertension is elevated blood pressure associated with an overall increase in resistance to blood flow through arterioles, where CO is typically normal.

Hypertension is typically caused by a combination of several (multifactorial) abnormalities causing of increased peripheral vascular resistance in essential hypertension.

• Autonomic nervous system function
• Baroreceptor reflexes
• The renin-angiotensin-aldosterone system
• Renal-Regulation

Question 2

What is the basis of Angina Pectoris?

Answer 2

Angina Pectoris (Chest) pain Results from an imbalance of oxygen supply and demand placed on myocardial tissue. This can be due to blockage or spasm of coronary arteries, resulting in pain.

Myocardial O2 demand increases with increased HR, contractility, Arterial pressure, or ventricular volume (Preload & Afterload)

These occur during physical exercise & sympathetic discharge which often precipitate angina in patients with Obstructive Coronary Artery Disease (OCAD)

Myocardial O2 Supply

Question 3

What is the basis of treating Hypertension?

What drug types are used?

Answer 3

The treatment of hypertension lies in modulating the factors influencing Blood Pressure (BP). Thus, given (COxPVR=BP), the targets of drugs are Peripheral Vascular Resistance (PVR) and/or Cardiac Output (CO).

1. Sympathomimetics: Adrenergic agents
   
   1. a-agonist
   2. a-blockers
2. Vasodilators
   
   1. CCB
3. Renin/Angiotensin Agents
   
   1. ACE-Inhibitors
   2. ARB
   3. Renin Inhibitors
4. Diuretics

Question 4

How do diuretics affect Hypertension?

What are the subtypes of diuretics used in HTN?

Answer 4

Diuretics lower blood pressure by depleting the body of sodium and thereby reducing blood volume through renal mechanisms.

Reducing the blood volume decreases the Stroke Volume (SV) of the heart, thereby decreasing Cardiac Output (CO) and subsequently decreased BP.

Types of Diuretics:

1. Thiazides
2. Loop Diuretics
3. K+ Sparing
4. Carbonic Anhydrase Inhibiting
5. Vasopressin (ADH) receptor Inhibitors
6. Osmotic Diuretics

Question 6

A blood pressure of 138/78 would fall under what category?

Answer 6

Hypertension Stage 1:

BP=Sys/Dias

Systolic: 130-139 OR Diastolic: 80-89

Question 7

A blood pressure of 115/85 would fall under what category?

Answer 7

Hypertension Stage 1:

BP=Sys/Dias

Systolic: 130-139 OR Diastolic: 80-89

Question 8

A blood pressure of 115/78 would fall under what category?

Answer 8

Normal

BP=Sys/Dias

Systolic: <120 AND Diastolic: <80

Question 9

A blood pressure of 125/75 would fall under what category?

Answer 9

Elevated:

BP=Sys/Dias

Systolic: 120-129 AND Diastolic: <80

Question 10

A blood pressure of 182/115 would fall under what category?

Answer 10

Hypertensive Crisis:

BP=Sys/Dias

Systolic: >180 AND/OR Diastolic: >120

Question 11

A blood pressure of 155/75 would fall under what category?

Answer 11

Hypertension Stage 2:

BP=Sys/Dias

Systolic: >140 AND Diastolic: >90

Question 12

How does the Sympathetic Nervous System affect the CV system?

The renal system?

Answer 12

SNS modulates CV through

1. Heart Rate (B-Adrenoceptor)
2. Contractility (B-Adrenoceptor)
3. Renin release from the Kidney (B-Adrenoceptor)
4. Peripheral vascular tone (PVR) (a-Adrenoceptor)

Question 13

What are the Drug classes & examples given to treat Hypertension?

Answer 13

Sympatholytics:

a-blocker: Doxazosin (Cardura)

a-agonist: Clonidine (Catapres)

Vasodilators:

CCB: Amlodipine (Norvasc)

Angiotensin/Renin Agents:

ACE-Inhibitor: Lisinopril (Prinivil)

ARB: Losartan (Cozaar)

Renin-inhibitor: Aliskiren (Tektuma)

Diuretics:

Thiazide: Hydrochlorothiazide (HCTZ)