Heart Drugs Flashcards

1
Q

What is the mode of action of Lidocaine?

A

Inactivates Na gated channels in both nerves AND cardiac muscle

Therefore decreases conduction.

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2
Q

What are the side effects of lidocaine?

A

CNS activation / depression
Hypotension

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3
Q

How is lidocaine administered?

A

Is not orally active so has to be given by injection
Metabolised by liver
1/2 life = 90-120 mins

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4
Q

Describe the 4 phases of the cardiac cycle

A

Phase 0 – rapid depolarisation due to voltage-gated Na+ channels opening – Na+ flows into myocyte.
Phase 1 – initial repolarisation – Na+ channels close, DRKC open – K+ leaves myocyte
Phase 2 – plateau – Ca2+ channels opened (time and voltage dependent) – Ca2+ in = K+ leaving. Ca channels stay open until end of plateau phase when they start to close.
Phase 3 – rapid repolarisation – Ca2+ channels closed, DRKC open, K+ leaves – myocyte repolarises.
Phase 4 – resting potential – K+ leaves myocyte through IRKC

K+ channels – are 2 types = inward rectifier K+ channels and delayed rectifier K+ channels.
- Inward rectifier K+ channels (IRKC) = maintain resting Vm until AP. Open when Vm <-60mV. Function – to clamp the Vm at rest by letting K+ out of cell, repolarising it.
- Delayed rectifier K+ channels (DRKC) = part of AP – open when membrane depolarises and closes after time delay = is both voltage and time dependent.

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5
Q
A
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6
Q

How do β blockers affect the nodes?

A

They slow spontaneous depolarisation of cardiac tissue

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7
Q

Which drugs are considered Class I in the VW classification?

A

Class I = Fast channel blockers

Disopyramide
Lidocaine
Flecanide

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8
Q

Which drugs are considered Class II in the VW classification?

A

Class II = Β blockers

Bisoprolol
Atenolol

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9
Q

Which drugs are considered Class III in the VW classification?

A

K+ channel blockers

Amiodarone

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10
Q

Which drugs are considered Class IV in the VW classification?

A

Ca Channel Blockers

Verapamil
Diltiazem

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11
Q

How do Class 1 agents selectively inhibit tachycardias?

A

They bind strongly when the channel is open or inactive (not resting).

Therefore the more frequently the channel is open (e.g. in tachycardia) - the greater the block.

Thus they inhibit tachycardia but allow normal HR

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12
Q

What is the difference between class 1 drugs?

A
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13
Q

What is flecanide used for?

A

Paroxysmal AF
AVRT
WPW

Slows condition in accessory pathways
Stabilises atria

DONT USE FOR VENTRICULAR ARRHYTHMIAS

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14
Q

What are the SEs of flecanide?

A

Can be pro-arrhythmic - do Echo prior to starting to check for abnormalities

Increases pacing thresholds - do pacemaker check before prescribing

Dizziness
Blurred vision
(Because it acts on neurological tissue as well as heart tissue)

Do ECG before starting and changing dose

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15
Q

Is amiodarone lipo-phillic or lipo-phobic?

A

Lipiophillic - highly - concentrates in the fat in the body

Means it has a LONG half life!

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16
Q

What is the loading dose of amiodarone?

A

200mg TDS - 1 week
200 mg BD - 1 week
200mg OD

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17
Q

Which molecule does amiodarone contain?

A

Iodine

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18
Q

How does amiodarone work?

A

Blocks ion channels inc delayed rectifier K+ channels = prolonged action potential (delays Phase III depolarisation)

Stabilises atrial and ventricular myocytes
Slows AV node conduction
Blocks accessory pathways

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19
Q

What are the side effects of amiodarone?

A

Lots!
Inc blue grey skin

Initially it causes pneumonitis which can progress to fibrosis

Iodine - important in thyroid hormone - can cause hyper and hypo thyroid

Secreted in tears - can become deposited on the cornea and cause keratitis. Can cause visual problems at night

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20
Q

How often should Ps on amiodarone be monitored?

A
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21
Q

What can amiodarone be used for?

A

AF - when other medication has failed to control

Malignant ventricular arrhythmias

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22
Q

Apart from amiodarone, which other Class III agent can be used for arrhythmias?

A

Dronedarone

Not used very often - used as an alternative to amiodarone when they can’t tolerate it - much less effective than amiodarone

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23
Q

What are the following receptors in the adrenergic system responsible for?
- α 1
- α 2
- β 1
- β 2

A
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24
Q

Which drug is first line for most tachyarrhythmias?

A

β blockers

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25
What can β blockers be used for?
Tachyarrhythmias Ectopic beats VF VT SVT AF
26
How do calcium channel blockers work?
They block calcium channels = less intracellular calcium => Smooth muscle relaxation Decreased force of cardiac contraction Decreased AV node conduction
27
When are calcium channel blockers contraindicated?
Severe left ventricular dysfunction = dont want to reduce the force of contraction that you have? Their use is limited to structurally and functionally normal hearts
28
29
When are Verapamil and Diltiazem used?
Not effective for ventricular arrhythmias Only used for supraventricular arrhythmias Mainly - AF - slows ventricular rate by blocking the AVN. Also used for SVT - IV Verapamil is 2nd line (not if on β blocker or has HF). Oral V or D used to prevent SVT.
30
How does Adenosine work?
Blocks the AV node conduction via the A1 receptor Used IV to terminate SVT
31
What is adenosine used to treat?
SVTs - given rapid IV Will terminate - AVNRT, atrioventricular tachycardia Will temporarily slow & reveal - atrial tachycardia & atrial flutter Will reveal occult accessory pathways
32
What are the side effects of adenosine?
Nasty drug - slows the heart aggressively and causes marked vasodilation and poss bronchoconstriction, Ps feel like they are dying for about 20 seconds - chest tightness, breathlessness, dizziness, nausea, hypotension (from vasodilation)
33
When is adenosine contra indicated?
In asthmatic patients - because it causes bronchoconstriction
34
How does atropine work?
Is a competitive antagonist of ACh muscarinic receptors (M1 - M5) Cardiac action - blocks M2 receptors - increases SAN rate and AV conduction - increases HR. Does the opposite of adenosine
35
What is atropine used for?
Sinus bradycardia 2nd or 3rd degree HB at the AVN (i.e. narrow complex). Does not work for HB below the AVN - only works on conduction tissue at the AVN level or above. If broad complex - atropine will not work.
36
Why do Ps who have an inferior MI often become bradycardia?
Because the RCA that causes inferior infarcts supplies the SAN and AVN
37
How does isoprenaline work?
Is a non-selective β agonist - inc HR, force of contraction and vasodilator
38
What is isoprenaline used for?
2nd / 3rd degree HB below the AVN I.e. HB with broad complexes Only ever given as a bridge to a pacemaker
39
Which channel is the one responsible for cardiac auto-tonicity?
If channel (funny channel) Uses a large Na+ current inward and tiny K+ current outward
40
Which drug is used as a specific blocker of the If current - therefore acts solely on the SAN to reduce HR?
Ivabradine
41
Why can Ivabradine not be used in AF?
The SAN doesn't work in AF - therefore will have no effect
42
What is Ivabradine used for?
Inappropriate sinus tachycardia - e.g. post-covid, POTS
43
How does Digoxin work?
Inhibits Na+/K+ ATPase pump - inc Na+, inc intracellular Ca - thus increases contractility of the heart. Not known why - but slows AVN conduction as a result
44
What is digoxin used for?
AF - but often 2nd or 3rd line Due to the fact it has a narrow therapeutic window and can cause almost every arrhythmia possible
45
How can digoxin present on ECG?
With a reverse tick
46
What is the antidote to digoxin?
Digibind
47
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49
50
Do drugs help improve prognosis in arrhythmias?
No - they reduce frequency and help Sx but do not improve prognosis (Except β blockers in congenital long QT syndromes)
51
Which class of the VW classification drugs may be pro-arrhythmic?
Class I and III May prolongate QT and QRS intervals
52
53
What do we want to do when treating angina?
Reduce O2 demand Increase O2 supply
54
Can you improve the O2 supply if there is fixed stenosis?
Not without stenting or bypassing the stenosis
55
Which are the most effective anti anginal drugs?
β blockers They reduce HR and force of contraction => reduction of myocardial O2 demand
56
57
What forms of nitrate are there?
GTN Spray Slow release tablets - Isosorbide mononitrate & Isosorbide denigrate IV GTN & ISMN - for use in unstable angina
58
What are the side effects of nitrates?
Vasodilation can cause headache, hypotension, dizziness, syncope (GTN) Can also get tolerance with continuous use - need to take nitrate holidays or slow-release preparations.
59
How do Ca channel blockers work?
Dec intracellular Ca by blocking Ca channels => Dilation of arterioles Dec ionotropy Dec HR via SAN and AVN
60
Which Ca channel blocker only works by vasodilation?
Amlodipine - has no effect on the heart itself
61
Which drugs (1st and 2nd line) are used as anti platelets for chronic stable angina? Why are anti platelets used for chronic stable angina?
1st L = aspirin 2nd L = DOACs (Clopidogrel, then Prasugrel or Ticagrelor) Antiplatelets are used because patient has atherosclerotic obstructive artery disease underlying their angina. You therefore want to prevent thrombosis which might occlude an artery = anti-platelets.
62
Which anti-anginal drugs (1st and 2nd line) are used for chronic stable angina?
1st line = Bisoprolol (+ GTN prn) 2nd line = Diltiazem, Amlodipine, Isosorbine Mononitrate
63
Which anti-hypertensive drugs are first and second line for chronic stable angina?
1st line = Ramipril 2nd line = Losartan, Candesartan & Amlodipine
64
Which lipid-lowering agent is first and second line for chronic stable angina?
1st line = Atorvastatin 2nd line = Simvastatin or Rosuvastatin
65
What are the two aims when treating angina?
Want to reduce O2 demand Want to increase O2 supply
66
Which are the most effective anti anginal drugs?
β blockers - they reduce HR and ionotropy - thus reducing myocardial O2 demand
67
Why are nitrates used in the treatment of angina?
They reduce preload and afterload (by dilating veins and arterioles) - thus reducing cardiac workload
68
Which nitrates are given as - spray - slow release tablets - IV
Spray = GTN Slow release = isosorbide mononitrate IV = GTN/Isosorbide mononitrate
69
What are the side effects of nitrates?
Headache (can be severe and put Ps off using) Hypotension/dizziness Syncope (GTN)
70
Why do Ps have to have nitrate holidays? What can they use instead?
You can get tolerance with continuous use of nitrates = loss of effect Can use slow-release preparations instead
71
Why are calcium channel blockers used for angina?
They reduce afterload (by vasodilation) - amlodipine only works in this manner. They can also reduce contractility and HR = reduced demand on the heart
72
When choosing between a β blocker and Ca channel blocker for angina - what helps you choose which drug to go with?
β blocker good if Ps have HF, migraine or arrhythmias. Can cause ankle swelling. Ca channel blocker good if P has Raynaud's or hypertension, asthma, COPD, PVD or resting bradycardia.
73
When would you not use Ca channel blockers for angina?
If a P has an underlying diagnosis of HF. Calcium channel blockers, with the exception of amlodipine, should be avoided in heart failure as they can further depress cardiac function and exacerbate symptoms. Have a negative inotropic effect and may cause hemodynamic decompensation in patients with reduced ejection fraction.
74
First step for angina is to choose between β blocker and Ca channel blocker. What is the next step in Rx?
To add in the other drug - i.e. β blocker or Ca channel blocker depending on what was chosen first of all.
75
Why should you never use Diltiazem with a β blocker?
Together there is a combined propensity to block the AVN = this can cause profound bradycardia.
76
After starting a P on β blocker AND ca channel blocker, what is the next line Rx for angina?
Addition or substitution of: - Slow release nitrate (isosorbide mononitrate) - Ivabradine - Nicorandil - Ranolazine
77
Which anti-platelet drug is used for unstable angina?
Aspirin Some Drs also prescribe DOACs at this stage but not NICE guidance.
78
Which anti-anginal drug is used for unstable angina?
Bisoprolol GTN PRN
79
Which anti-coagulant drug is used for unstable angina?
Fondaparinux (or other LMWH) Fondaparinux often used because it is OD and cheap
80
Which investigations are done for unstable angina and why?
Serial ECGs - checking for ischaemia Repeat troponin - ?progressing to MI Echo - check LV function and see if there is a regional wall motion abnormality Coronary angiogram - ?whether P needs revascularisation
81
How do platelets aggregate to form a clot?
Plaque rupture exposures collagen VWF binds to this - allows platelets to adhere (uses GP1b receptor). Platelets nearby are then activated using GP2b3a receptors (binds with fibrinogen), P2Y12 receptors (needs ADP) and Tx Receptors (needs COX1)
82
Which anti-platelet drugs are used in IHD?
Aspirin DOACs
83
What is the downside of using clopidogrel?
There can be patient resistance to the drug - up to 40% of Ps dont get the full benefit. This means there is a huge variation in how Ps respond. Prasugrel and Ticagrelor are more reliable and potent that clopidogrel
84
What anti platelet Rx is given for stable IHD?
Aspirin PCI 6m of clopidogrel following PCI
85
What antiplatelet Rx is given for NSTE-ACS (i.e. unstable angina or NSTEMI)?
Aspirin - 300mg admission then long term 12m Prasugrel or Ticagrelor (sometimes Clopidogrel) However dont start 2nd agent straight away - often these Ps have something else going on - start 2nd agents when sure of the diagnosis (e.g. following coronary angiogram)
86
What anti platelet Rx is given for STEMI?
Aspirin + Praugrel or Ticagrelor at time of diagnosis LT = aspirin + 12m Prasugrel or Ticagrelor
87
When is LMWH contraindicated?
In Ps with severe renal impairment (<30 GFR) - because they are renally excreted. If severe renal impairment - the drug won't be excreted and therefore the P will be over anti-coagulated.
88
If LMWH is contraindicated due to renal impairment - what can be given instead?
Unfractionated heparin
89
Which anticoagulant is given routinely during angiography via the radial artery and during PCI?
Unfractionated heparin
90
4mm ST elevation in leads II, III and aVF would indicate what?
Inferior STEMI - Right coronary artery occlusion
91
What timeframe do you have for PCI to be undertaken?
Within 2 hours
92
Why is PCI preferred to thrombolysis?
Thrombolysis = less reliable than PCI - only open up about 50%, often only achieves partial flow, and has major bleeding risks.
93
Which two drugs are used for thrombolysis?
Alteplase Tenecteplase
94
What is the difference between secondary prevention and primary prevention in IHD?
95
If an echo shows LV anteroseptal akinesia - which coronary artery is like to have been occluded?
LAD
96
Which drugs should be given to patients post-MI?
97
Which anti-platelet drugs are given to Ps post MI? Why?
Aspirin Prasugrel or Ticagrelor Both prevent plaque and stent thrombosis
98
Which anti-hypertensive classes should be given to a P post MI? Why?
β blockers ACEI Aldosterone antagonist All help prevent HF and LV remodelling. β blockers additionally stop arrhythmias. Finally all improve prognosis.
99
What community care is given to Ps after suffering an MI?
100
101
What is the MOA of Abciximab?
Glycoprotein 2b/3a antagonist
102
What lifestyle advice should be given to Ps with IHD for primary and secondary prevention?
103
What are the commonest causes of exertional syncope?
Hypertrophic cardiomyopathy Dilated cardiomyopathy Arrhythmogenic cardiomyopathy
104
What is a cardiomyopathy?
Disease of the cardiac muscle
105
What is the difference between dilated and hypertrophic cardiomyopathy?
Dilated = LV wall is stretched and weakened Hypertrophic - LV wall is thickened
106
What causes dilated cardiomyopathy?
Ischaemic causes = IHD - 70% (e.g. chronic ischaemia due to multi vessel disease) Non-ischaemic causes = - HT (2nd commonest cause) - Congenital - ETOH - Viral - Toxins (chemo drugs) - Metabolic - hypothyroid, iron overload, thiamine deficiency - Idiopathic
107
What type of HF is caused by dilated cardiomyopathy?
HFrEF Dilated ventricle = high diastolic volume, impaired systolic function => reduced ejection fraction
108
What is the standard Rx for HFrEF?
ACEI β blocker Aldosterone antagonist SGLT2 inhibitor
109
What conditions require anti-thrombotic medication?
CAD - angina, STEMI, NSTE-ACS, post-PCI and post-CABG AF Mechanical heart valves LV aneurysm with thrombus
110
What is the MOA of aspirin?
Irreversible inhibitor of COX1 COX1 - involved in both promoting and inhibiting platelet aggregation Stimulates both Thromboxane - promotes and prostacyclin - inhibits Under normal circumstances - these two molecules cancel each out - however when you give high dose aspirin - you inhibit both But at LOW dose - you only inhibit Thromboxane & platelet aggregation - which means prostacyclin and its inhibition of platelet aggregation dominates
111
When is aspirin given?
MI ACS Angina Post PCI / Post CABG
112
What are the SE of aspirin?
Peptic ulceration - give PPI Rash Ototoxic at high dose Reyes syndrome in children - fatal brain and liver damage
113
What is the name of the syndrome that aspirin can cause in children?
Reye's syndrome
114
How does clopidogrel work?
Inhibits P2Y12 receptors - stops platelet adhesion, aggregation and activation
115
What are the SEs of clopidogrel?
Bleeding - effects can last for 7 days after cessation - can be CI for surgery Rash 40% have clopidogrel resistance - do not get full platelet inhibition
116
How do ticagrelor and prasugrel work?
Both inhibitor P2Y12 - more potent and reliably than clopidogrel
117
What are the SEs of ticagrelor and prasugrel?
Bleeding risk = more than clopidogrel. Prasugrel has the highest risk. Ticagrelor can cause breathlessness
118
Which drugs target the GP2b3a receptor?
Abciximab Tirofiban
119
What is the risk of Abciximab and Tirofiban?
They are very powerful anti-thrombotic drugs Therefore carry high bleeding risk
120
When are abciximab and tirofiban used?
Only during high risk coronary stent procedures
121
What drugs are given for CAD?
Aspirin (or clopidogrel if intolerant) DAPT given for 12m following ACS - Prasugrel or Ticagrelor DAPT given for 6m following elective PCI - Clopidogrel 2b3a only given during high risk PCI
122
When do we start DAPT?
If definitely a STEMI - start both drugs immediately Elective PCI - prior to procedure Non-STE ACS - give aspirin at diagnosis and 2nd agent after angiogram has confirmed diagnosis
123
What drug needs to be given with a mechanical heart valve?
Warfarin
124
What are usual target INR levels when on warfarin?
2-3 Can go as high as 3.5-4.5
125
What is the mode of action of warfarin?
1972 was diSCo Inhibits - 2, 7, 9 and 10, protein C and protein S
126
What things does warfarin interact with?
Alcohol Green vegetables Abx, anticonvulsants and more drugs Metabolised by CP450
127
When is warfarin used?
Mechanical heart valves Mitral stenosis w AF Intra-cardiac thrombus
128
When are DOACs preferred to warfarin/
AF Stroke prophylaxis DVT PE
129
How can warfarin be reversed?
Slowly with Vit K Rapidly with IV blood factors
130
What are the SEs of warfarin?
Teratogenic Warfarin induced skin necrosis (if you start warfarin with out heparin anticoagulation - the first thing that gets inhibited are Protein C & S - short 1/2 L. Means that without heparin the P is transiently hypercoaguable = skin necrosis)
131
Which factors does heparin inhibit
2+7 =9,10,11,12
132
Which pathway is used to monitor heparin?
APTTr (intrinsic pathway)
133
What is used to monitor warfarin?
Extrinsic pathway - INR
134
What are the side effects of heparin?
Bleeding
135
What is the antidote for heparin?
Protamine - potent vasdilator
136
When is heparin used?
CKD Dialysis ECMO / Bypass Elective PCI
137
Which are the LMWH?
Dalteparin Enoxaparin Tinzaparin
138
What are LMWHs used for?
NSTE-ACS AF In pregnancy in place of warfarin
139
When are LMWHs contra-indicated?
When there is poor renal function - they are renally cleared
140
What is the serious side effect of heparin?
HIT - Heparin Induced Thrombocytopenia More common with UFH than LMWH - caused by ABs (previous exposure) - activate platelets causing a prothrombotic state
141
What are the S&S of heparin induced thrombocytopenia?
Falling platelet count Blood clot - either growing or new Can get skin necrosis
142
When is anticoagulation recommended using CHADVASC?
1 = should be considered 2 = anticoagulation is recommended
143
How do DOACs work?
Inhibit FactorX
144
What are the DOACs?
Rivaroxaban Apixaban Edoxaban Dabigatran (but Factor 2a not Xa)
145
What is the mode of action of Dabigatran?
Thrombin inhibitor (2a)
146
When are DOACs used?
AF DVT PE
147
Why are DOACs preferred to warfarin?
More reliable Less monitoring Fewer interactions Similar bleeding risk
148
When should you consider fibrinolysis in acute thrombotic stroke?
If a P cannot (or has not) transferred to PCI within 2 hours
149
Which drugs are used for fibrinolysis?
Alteplase Tenecteplase
150
How do alteplase and tenecteplase work?
Activate plasminogen into plasmin - this breaks cross-links between fibrin molecules = breaks down clots
151
What are the SEs of alteplase and tenecteplase?
High bleeding risk - 5%
152
How can you differentiate between acute and chronic HF?
Acute = causes pulmonary oedema Chronic = peripheral oedema
153
At what BP can Ps said to be in cardiogenic shock?
<90mmHg
154
What do we want to stop in order to treat HF?
Stop RAAS Stop SS activation Give diuretics
155
How do loop diuretics work?
Block NaK2Cl transporter in LOH = loss of Na = loss of water V powerful Also cause vasodilation of pulmonary arteries
156
What are loop diuretics used for?
Peripheral oedema IV for acute pul oedema
157
Which drugs are loop diuretics?
Furosemide Bumetanide
158
What are the SEs of loop diuretics
Ototoxicity Low K Low Na, Ca & Mg Inc uric acid Dehydration Renal impairment
159
Why do you get hypokalaemia with loop diuretics?
Get Na loss in the LOH = means more Na travels to the DCT - where more Na/K is activated - causing Na reabsorption and loss of K+ = hypokalaemia
160
Which are the ACEIs?
Ramipril Lisinopril Enalapril
161
What are the SEs of ACEIs?
162
Which SEs of ACEIs are caused by excess bradykinin?
Dry cough Angioedema
163
How do AR2Bs work?
Block ATII effect - similar effect to ACEIs without the cough
164
Which drugs are AR2Bs?
Losartan Candesartan
165
How do aldosterone antagonists work?
Block upregulation of Na channels in the DCT by aldosterone = less Na reabsorbed = more water excreted = less pressure in the vessels
166
Which drugs are aldosterone antagonists?
Spironolactone Eplerenone Amiloride
167
What are aldosterone antagonists also known as?
Potassium-sparing diuretics
168
What are the side effects of spironalactone?
Impaired renal function Hyperkalaemia Gynaecomastia
169
Why does the SS nervous system get activated in HF?
Low CO = SS activation = inc ADR this increases contractility -> inc CO also - activates RAAS = vasoconstriction = inc afterload
170
Why is SS activation in HF a bad thing?
Causes cardiotoxicity from the catecholamines -> structural changes inc LV dilation and adverse remodelling -> in LV systolic dysfunction
171
What does activation of β 1 receptors cause?
inc HR inc contractility inc renin release
172
Which β blockers are used in HF?
Bisoprolol Carvedilol
173
Why are β blockers used in HF?
Slow HR = inc diastolic filling time Reduce afterload (BP) Reduce renin release by reducing RAAS activation Do not affect contractility (unlike calcium blockers)
174
What are the SEs of β blockers?
Fatigue Bradycardia Breathlessness Inc asthma Claudication, cold hands / feet, Erectile dysfunction
175
Why can β blockers not be good for diabetic Ps?
They mask the Sx of hypoglycaemia
176
Which drug works by blocking in the If current in the SAN?
Ivabradine
177
Which SGLT2 inhibitor has the strongest evidence base for CHF?
Dapagliflozin
178
What are the 4 pillars of HFrEF management?
ACEi / ARB / ARNI BB MRA (Spironalactone) SGLT2i
179
If Sx persist in HFrEF - what can ACE/ARB by replaced with?
Valsartan - if EF <35%
180
If Sx persist in HFrEF - what meds can be added?
Ivabradine Hydralazine and nitrate Digoxin (if sinus rhythm)
181
How does Valsartan work? What is the main SE?
Neprilysin inhibitor SE = angio-oedema - high incidence
182
What can cause acute HF?
MI Valve dysfunction
183
What is the most serious potential complication of acute HF?
Cardiogenic shock - as heart is unable to maintain CO Ps will be cold, clammy, thready pulse, SBP <90
184
At what pulmonary capillary pressure will pulmonary oedema occur?
>25mmHg
185
What management do we do for acute HF?
PODMAN Position - sit upright Oxygen Diuretics - IV furosemide Morphine Anti-emetic Nitrate - GTN spray, IV isosorbide mononitrate
186
What drug must you not give in acute HF?
Β blockers Decreased Cardiac Output: In acute heart failure, the heart’s pumping ability is severely impaired. Beta-blockers can further reduce cardiac output due to their negative inotropic and chronotropic effects, worsening the condition. Worsening Symptoms: By lowering the heart rate and contractility, beta-blockers can exacerbate symptoms such as shortness of breath and fatigue due to insufficient blood flow and oxygen delivery to tissues. Inadequate Perfusion: Reduced cardiac output and blood pressure can lead to inadequate perfusion of vital organs, which is especially dangerous in acute settings where the body's demand for oxygen and nutrients is high.
187
What are the steps of managing acute HF according to NICE?
Pul oedema? Give IV furosemide If not effective - start NIV ventilation If still not good - Intubate and ventilate Only give nitrates if HT, MI or MR/AR Opiates - use for severe distress
188
If Ps have cardiogenic shock and acute HF - what type of drug can be given?
Inotropes & Pressors
189
What types of NIV can be given in acute HF?
CPAP BiPAP
190
How is cardiogenic shock managed?
TREAT MAIN CAUSE IV saline (not if pul oedema!) Ionotropes - dobutamine, adrenaline Pressors - noradrenaline Intubate, ventilation, ECMO, intra-aortic ballo pump
191
What is cardiogenic shock most commonly due to?
Acute MI (STEMI more than NSTEMI - more myocardium damaged in STEMI) Acute valve dysfunction - endocarditis Arrhythmias Myocarditis Drug toxicity
192
What is ECMO?
Extra corporeal membrane oxygenation
193
What is CRT?
Cardiac resynchronisation therapy
194
When should Ps be considered for device therapy in CHF?
Ps with poor LV function - with EF <35% and BBB should be considered - especially LBBB.