Heart Failure and Angina

Question 1

Goals of HF Management

Answer 1

1. decrease congestion with diuretics
2. modulate neurohormonal activation w/ RAAS antagonists and B-Blockers
3. improve flow, if possible with vasodilators

Question 2

Digoxin MOA

Answer 2

inhibits Na/K pumo of cell membrane –> Na levels within cells rise, inactivating a Na/Ca symporter –> Calcium levels in cell rises –> more Ca is stored in SR –> more Ca available for contractility

Question 3

Digoxin Physiologic effects

Answer 3

HR is slowed at the SA node and AV conduction is slowed (vagal response at low doses)
toxic levels may upset resting membrane potential and cause arrhythmias

Question 4

Milrinone MOA

Answer 4

parenteral inotrope. inhibits phosphodiesterase, increases cAMP which increases Ca++ influx
increases Calcium = increased contractile force

Question 5

Nitrate MOA

Answer 5

Nitrates are converted into NO in vascular smooth muscle –> NO activates guanylate cyclase which increases the conversion of GTP-cGMP –> cGMP mediates relaxation of smooth muscle

Question 6

Nitrate Uses

Answer 6

SL –> tx of acute angina

PO/transdermal –> prophylaxis in stable angina

Question 7

Nitrate physiologic effects

Answer 7

decreases LVEDP
decreases myocardial O2 demand
increases perfusion of tissue

Question 8

Nitrate Drugs

Answer 8

Nitroglycerin
Isosorbide Mononitrate
Isosorbide Dinatrate

Question 9

Ca++ channel blocker Drugs

Answer 9

verapamil
diltiazem
nifedipine (“dipines”)

Question 10

CCBs MOA

Answer 10

blocks L-type calcium channels in cardiac smooth muscle and prevents Ca++ from entering the cell
Arterioles are more sensitive than veins

Question 11

Dihydropyridines sensitivity

Answer 11

more effective on dilation of vasculature than supression of contractility and nodal conduction

Question 12

Diltiazem and Verapamil Sensitivity

Answer 12

Great effect on SA/AV nodal tissue (phase 0) and muscle (phase 2). Also have vasodilatory effects

Question 13

CCB uses

Answer 13

Angina: decreases PVR and O2 requirement of the heart. decreases arterial tone
Arrhythmia, HTN, premature labor and ICP in subarachnoid hemorrhage

Question 14

CCB adverse effects

Answer 14

Gingival hyperplasia
AV block and bradycardia (diltiazem, verapamil)
flushing/edema/dizziness (dipines)
nausea/constipation

Question 15

Ranolazine MOA

Answer 15

In ischemia, CVD, hypertrophy: late Na+ current fails to inactivate, which leads to increased Na+ intracellularly. THis reverses the Na/Ca exchange and increases intracellular Ca++. Calcium overload can lead to mechanical dysfunction and O2 demand/supply imbalance
Inhibits Na current

Question 16

Ranolazine Uses

Answer 16

Angina in addition to standard treatment
can substitute BB is they are not tolerated
Can prolong the QT interval

Question 17

Beta Blocker Drugs

Answer 17

Metoprolol and Atenolol are the most cardioselective

Question 18

Beta Blocker MOA

Answer 18

decreases HR, decreases BP, decreases contractility
these all decrease oxygen demand.
Can block reflex tachycardia seen in nitrates. Not a vasodilator so not helpful in variant angina