Cardiac Contractility/Positive Inotropic medications

Question 1

• LV End Diastolic Volume (EDV)-

Answer 1

amount of blood in left ventricle at the
end of diastole
* LV EDV = Preload

Question 2

• Afterload-

Answer 2

pressure heart has to overcome to eject blood
 Afterload = Systemic blood pressure

Question 3

• LV End Systolic Volume (ESV)-

Answer 3

amount of blood in left ventricle at the end
of systole

Question 4

• Stroke Volume (SV):
• Ejection Fraction (EF):
• Cardiac Output (CO):

Answer 4

SV= EDV – ESV (mL)
EF= SV/EDV X 100% (%)
CO= HR X SV (mL/min)

Question 5

ionotrophy

Answer 5

the ability of the heart to contract

Question 6

Positive Inotropic medications
(5)

Answer 6

• Cardiac glycosides
• Digoxin- inhibits Na-K ATPase
• DOBUTamine- b1 adrenocepter agonist
• Milrinone- phosphodiesterase inhibitor
• Levosimendan- calcium sensitizer

Question 7

Positive Inotropic medications
Digoxin
* Brand name: (3)
* MOA:
* Use: (2)

Answer 7

Digitek, Lanoxicaps, Lanoxin (available IV/PO)
inhibition of Na+-K+ ATPase/ vagal tone to heart
heart failure, atrial fibrillation (rate-control)

Question 8

Positive Inotropic medications
Digoxin
ADRs (narrow therapeutic index medication):
(3)

Answer 8

• Nausea, vomiting, diarrhea
• Bradycardia/ heart block
• Visual disturbances (green-yellow halo)

Question 9

Positive Inotropic medications
Digoxin
Drug-Drug interactions:
(3)

Answer 9

• Other drugs that cause bradycardia or hypokalemia
• Increased levels with macrolide antibiotic
• Increase risk of arrhythmia with adrenergic agonists or succinylcholine

Question 10

Digoxin
— effects with – K+

Answer 10

increase
decrease

Question 11

Positive Inotropic medications
Digoxin- Dental Implications
* Monitor …
* Increased — may make dental procedures,
such as taking radiographs or impressions difficult
* After supine positioning, …
* Use — with caution (adrenergic stimulation)
* Avoid ..
* — protocol

Answer 11

vital signs
gag reflex
have patient sit upright
for at least 2 minutes before standing to avoid
orthostatic hypotension (bradycardia)
vasoconstrictors
dental light in patient’s eye/offer dark glasses
Stress reduction

Question 12

Positive Inotropic medications
DOBUTamine
* Brand name:
* MOA:
* Use: (2)

Answer 12

Dobutrex (only available IV)
b1- adrenergic receptor agonist
acute decompensated heart failure, cardiogenic shock

Question 13

Positive Inotropic medications
DOBUTamine
ADRs:
(3)
* Drug-Drug interactions: none of significance
* Dental Implications: none

Answer 13

• Increased heart rate and blood pressure
• Arrhythmias
• Chest pain

Question 14

Positive Inotropic medications
Levosimendan
* Brand name:
* MOA:
* Use:

Answer 14

Simdax (not available in the U.S.)
Sensitize troponin to Ca2+ (inotropy) and KATP channel activation
in smooth muscle (vasodilation)
acute decompensated heart failure

Question 15

Positive Inotropic medications
Levosimendan
* ADRs:
(3)
* Drug-Drug interactions: none of significance
* Dental Implications: none

Answer 15

• Arrhythmias (ectopic beats, NSVT, VT)- supposedly less than DOBUTamine
• Hypotension
• Headache

Question 16

Myocardial Oxygen Supply
Function of:
(2)

Answer 16

1. Arterial O2 content
2. Coronary blood flow

Question 17

1. Arterial O2 content

Answer 17

• decreased anemia and hypoxia

Question 18

2. Coronary blood flow

Answer 18

• decreased atherosclerosis and vasospasm

Question 19

Myocardial Oxygen Supply is a function of

Answer 19

Heart Rate
Cardiac myocytes supplied with blood during diastole
increased Heart rate = dcereased time in diastole

Question 20

Myocardial Oxygen Demand (MVO2)
MVO2Determinants
(3)

Answer 20

1. Heart rate
2. Myocardial contractility
3. Myocardial wall stress
   * Preload
   * Afterload

Question 21

Surrogate marker for MVO2

Answer 21

Double Product= HR X SBP

Question 22

SYMPATHETIC Nervous System
b1 adrenoreceptors
(5)

Answer 22

• increased force of contraction
  (positive inotropic effect)
• increased heart rate (positive
  chronotropic effect)
• increased automaticity
• Repolarization
• Reduced cardiac efficiency

Question 23

PARASYMPATHETIC Nervous System
Muscarinic (M2) receptors
(3)

Answer 23

• Cardiac slowing
• decreased automaticity
• Inhibition of AV node
  conduction

Question 24

• Organic nitrates-

Answer 24

increased myocardial O2 supply

Question 25

* Calcium channel blockers-

Answer 25

increased myocardial O2 supply and decreased O2 demand

Question 26

* b-adrenocepter antagonists-

Answer 26

decreased myocardial O2 demand

Question 27

* Ranolazine-

Answer 27

improves angina w/o changing BP or HR

Question 28

* Ivabradine-

Answer 28

not approved for angina in U.S.

Question 29

Antianginal medications Organic nitrates * Forms: (4)

Answer 29

* Organic nitrates -Nitroglycerin - Isosorbide dinitrate/mononitrate * Sodium Nitroprusside

Question 30

Antianginal medications Organic nitrates * Major side effects (5)

Answer 30

* Headache * Syncope/hypotension * Tachycardia * Tolerance * Methemoglobinemia

Question 31

Antianginal medications Organic nitrates * Contraindicated with

Answer 31

PDE-5 Inhibitors

Question 32

Antianginal medications Organic nitrates- Available products

Answer 32

* SL tablets * Spray * Intravenous * Ointment * Patch * Capsules * LA tablets * Isosorbide mononitrate (ISMN) * Isosorbide dinitrate (ISDN)

Question 33

Immediate relief

Answer 33

* SL tablets * Spray * Intravenous * Ointment

Question 34

Prevention

Answer 34

* Patch * Capsules * LA tablets * Isosorbide mononitrate (ISMN) * Isosorbide dinitrate (ISDN)

Question 35

Antianginal medications Organic nitrates Isosorbide Mononitrate * Brand name: (2) * MOA: * Use: (2)

Answer 35

Imdur, Ismo Stimulate production of intracellular cGMP Angina and heart failure

Question 36

Antianginal medications Organic nitrates Isosorbide Mononitrate ADRs: (4)

Answer 36

* Headache (common), flushing, dizziness, postural hypotension

Question 37

Antianginal medications Organic nitrates Isosorbide Mononitrate Drug-Drug interactions:

Answer 37

* Increased effects with other vasodilator type medications

Question 38

Antianginal medications Organic nitrates- Dental Implications * Monitor ... * --- protocol * After supine positioning, * Use --- with caution * --- available for acute angina attack

Answer 38

vital signs Stress reduction have patient sit upright for at least 2 minutes before standing to avoid orthostatic hypotension vasoconstrictors Sublingual nitroglycerin

Question 39

Antianginal Medications Calcium Channel Blockers MOA:

Answer 39

Block calcium from entering cell through voltage sensitive “slow” L-type channels * Slow conduction in SA and AV node (non-dihydropyridine) *  heart rate * AV block * Vasodilatation of arterioles * Decrease arterial pressure and wall tension * Decrease myocardial contractility * Increase flow through areas of fixed coronary obstruction

Question 40

Antianginal Medications Calcium channel blockers Amlodpine * Brand name: * MOA: * Use: (3)

Answer 40

Norvasc Dihydropyridine calcium channel blocker Angina, hypertension, also vasospastic angina

Question 41

Antianginal Medications Calcium channel blockers Amlodpine ADRs: (6)

Answer 41

* Edema (common), dizziness, lightheadedness, hypotension, flushing, gingival enlargement (rare- but more common than non-DHP)

Question 42

Antianginal Medications Calcium channel blockers Amlodpine Drug-Drug interactions: (2)

Answer 42

* Hypotension with sedatives, opioids, general and inhaled anesthetics * NSAIDS reduce blood pressure lowering effect

Question 43

Antianginal Medications Calcium channel blockers- Dental Implications * Monitor ... * Consider ... * --- appointments * After supine positioning, * Use (2) with caution * Place on frequent recall to monitor for ---

Answer 43

vital signs stress reduction protocol Shorter have patient sit upright for at least 2 minutes before standing to avoid orthostatic hypotension vasoconstrictors and inhaled anesthetics gingival hyperplasia

Question 44

Antianginal medications β-adrenoceptor blockers * Block sympathetic stimulation to the heart (4)

Answer 44

* Decrease heart rate * Decrease automaticity - block NE’s effects on Ca2+ channels * Slow conduction through AV node (increase refractory period)

Question 45

Antianginal medications β-adrenoceptor blockers Prevent

Answer 45

ischemia * Decrease myocardial oxygen demand * decrease HR, decrease contractility, decrease SBP

Question 46

Antianginal medications β-adrenoceptor blockers * Prefer ---acting b1 selective agents for angina

Answer 46

long

Question 47

Antianginal medications β-adrenoceptor blockers Dental implications * Monitor ... * --- protocol * --- appointments * After supine positioning, * Use (2) with caution * Use -- effective dose of local anesthetics

Answer 47

vital signs (heart rate should be low) Stress reduction Shorter have patient sit upright for at least 2 minutes before standing to avoid orthostatic hypotension vasoconstrictors and inhaled anesthetics lowest

Question 48

Antianginal Medications Ranolazine * MOA: (2)

Answer 48

* inhibits late inward sodium current (Ina) in ischemic myocardium  reduced myocardial wall tension and O2 consumption * At higher concentrations inhibits rapid delayed rectifier potassium current (Ikr)  prolonged action potential and QT interval

Question 49

Antianginal Medications Ranolazine * Brand name: * MOA: * Use:

Answer 49

Ranexa Inhibition of late inward sodium current (Ina) Angina

Question 50

Antianginal Medications Ranolazine * ADRs: (6)

Answer 50

* Bradycardia, hypotension, dizziness, QT prolongation, TdP, xerostomia

Question 51

Antianginal Medications Ranolazine * Drug-Drug interactions: (1)

Answer 51

* Many due to CYP 450 3A4 metabolism

Question 52

Antianginal Medications Ranolazine Dental implications: (2)

Answer 52

* Assess salivary flow as a factor in caries, periodontal disease, and candidiasis * Use vasoconstrictors and inhaled anesthetics with caution