Chapter 2 – Cardiovascular System
ARRHYTHMIAS Amiodarone (Cordarone X)
Dose: 200mg TDS for 1 week then 200mg BD for
Anti-Arrhythmics
1 week then 200mg OD
Class 1A Disopyramide MHRA/CHM (2015): risk of severe bradycardia
Class 1B Lidocaine and heart block when antivirals (sofosbuvir,
Class 1C Flecainide, Propafenone daclatasvir) are used with AD
Class 3 Amiodarone, Dronedarone
SEs: arrhythmias, pancreatitis, SCARs,
Disopyramide (Rythmodan) photosensitivity, altered taste
M: hyperglycaemia, hypotension, ventricular Corneal microdeposits – reversible on
tachycardia and fibrillation, torsades de pointes, withdrawal of Tx. If vision is impaired or optic
serum potassium neuritis/neuropathy occurs, discontinue to
prevent blindness
Lidocaine
Thyroid function – AD contains iodine.
Methaemoglobinaemia – can be treated with Hypothyroidism can be treated with
methylthioninium chloride replacement therapy without stopping AD
Flecainide Hepatotoxicity – discontinue if severe liver
function abnormalities occur
Dose adjustment – reduce dose by ½ when
using with amiodarone Pulmonary toxicity – report any new or
progressive shortness of breath or cough
Adenosine
Monitoring:
Indication: rapid reversion to sinus rhythm 1. TFTs – before Tx then every 6 months.
SEs: discontinue if chest pain or hypotension T4 (thyroxine) may be high in the absence
occurs, flushing, throat discomfort, AV block of hyperthyroidism, hence measure T3 (tri-
iodothyronine), T4 and TSH (thyroid-
Bradycardia – discontinue stimulating hormone).
Respiratory failure – discontinue Raised T3 and T4 with a low or undetectable
TSH = thyrotoxicosis
Dronedarone (Multaq) 2. LFTs – before Tx then every 6 months
3. Serum K+
Liver injury – discontinue Tx if 2 consecutive
4. Chest x-ray
alanine aminotransferase conc. exceed 3 times
upper limit of normal With antivirals – monitor closely. Pts at high
risk of bradycardia should be monitored
Heart failure – discontinue if heart failure or left
continuously for 48 hours after starting Tx.
ventricular systolic dysfunction develops
Advice:
Pulmonary toxicity – discontinue if dyspnoea or
1. Use a wide-spectrum sunscreen to protect
dry cough develops
against both long-wave UV and visible light
M: heart failure, ECG, serum creatinine, LFTs 2. With antivirals – report ASAP any SOB, light-
headedness, palpitations, fainting, unusual
Advice: report signs of heart failure and hepatic
tiredness or chest pain
disorders
, Chapter 2 – Cardiovascular System
Anti-Arrhythmics BLEEDING DISORDERS
Sotalol (Beta-Cardone, Sotacor) Anti-Fibrinolytics
Safety information – may prolong the QT
Tranexamic acid (Cyklokapron)
interval. Avoid hypokalaemia in Pts.
Indications: menorrhagia, local fibrinolysis,
X: long QT syndrome
epistaxis, hereditary angioedema
SEs: chest pain, sexual dysfunction, torsades de
X: H/O convulsions, thromboembolic disease
pointes (increased risk in females)
!: irregular menstrual bleeding (establish cause
M: correct hypokalaemia, hypomagnesaemia
before initiating therapy), haematuria, oral
Cardiac Glycosides contraceptives (risk of thrombosis)
SEs: diarrhoea (reduce dose)
Digoxin (Lanoxin)
Colour vision changes – discontinue
Indications: rapid digitalisation for AV or flutter,
heart failure (for Pts in sinus rhythm) Menorrhagia – exclude structural or histological
causes or fibroids
Dose adjustments – reduce dose by ½ with
concurrent use of amiodarone or quinine Coagulation Proteins
Dose conversion – reduce dose if digoxin has
Dried Prothrombin Complex
been given in the preceding 2 weeks. When
switching from IV to oral route, increase dose Indications: haemorrhage and major bleeding
by 20-33% to maintain serum concentration in warfarin Pts following phytomenadione
X: constrictive pericarditis, hypertrophic X: angina, H/O heparin-induced
cardiomyopathy, heart block, 2nd block AV thrombocytopenia, recent MI
block, supraventricular arrhythmias, ventricular
tachycardia or fibrillation Plasma Products
! (risk of toxicity): hypercalcaemia, Fresh Frozen Plasma
hypokalaemia, hypomagnesaemia, hypoxia,
recent MI, severe respiratory disease, sick sinus Indications: replacement of coagulation factors
syndrome, thyroid disease and major bleeding in warfarin Pts following
phytomenadione
SEs: arrhythmias, cardiac conduction disorder,
diarrhoea, eosinophilia, vision disorders, !: severe protein S deficiency
depression, dizziness
Calcium Channel Blockers
Monitoring:
1. Plasma-digoxin concentration – take blood Nimodipine (Nimotop)
6 hours post dose Indications: subarachnoid haemorrhage
2. Serum electrolytes
3. Renal function X: unstable angina, within 1 month of MI