Arrhythmias introduction Domina Petric, MD

Arrhythmias are common often benign often intermittent causing diagnostic difficulty occasionally severe causing cardiac compromise

Causes Cardiac Non cardiac caffeine smoking alcohol pneumonia drugs myocardial infarction coronary artery disease left ventricle aneurysm mitral valve disease cardiomyopathy pericarditis myocarditis abberant conduction pathways caffeine smoking alcohol pneumonia drugs metabolic imbalance phaeochromocytoma

Non cardiac causes Drugs that can cause arrhythmias are β2-agonists, digoxin, L-dopa, tricyclics, doxorubicin. Metabolic imbalance: K+, Ca2+ , Mg2+ , hypoxia, hypercapnia, metabolic acidosis and thyroid disease.

Symptoms palpitation chest pain presyncope, syncope hypotension pulmonary oedema asymptomatic

O History Past medical history and family history! Precipitating factors! Associated symptoms: chest pain, dyspnoea, collapse. Nature: fast or slow, regular or irregular. Duration! Drug history! Onset/offset!

Tests Full blood count! Urea, electrolytes and creatinine! Glucose! Calcium and magnesium ions! TSH!

Tests ECG Echocardiography Excercise ECG Cardiac catheterization 24 hours ECG monitoring Echocardiography Excercise ECG Cardiac catheterization Electrophysiological studies

Treatment overview of most common arrhythmias Part two Treatment overview of most common arrhythmias

Bradycardia If asymptomatic and rate >40 bpm, treatment is not necessary. If heart rate is less than 40 bpm or patient is symptomatic, treatment is ATROPINE 0,6-1,2 mg iv. (up to maximum 3 mg).

Isoprenaline infusion External cardiac pacing Bradycardia Temporary pacing wire Isoprenaline infusion External cardiac pacing Image source: Wikipaedia.org

Sick sinus syndrome Sinus node dysfunction can cause: bradycardia arrest sinoatrial block supraventricular tachycardia alternating with bradycardia/asystole (tachy-brady syndrome)

Sick sinus syndrome Atrial fibrillation and thromboembolism may also occur. If the patient is symptomatic, pacing may be necessary.

Sick sinus syndrome Image source: lifeinthefastlane.com

Supraventricular tachycardia Narrow complex tachycardia (rate >100 bpm, QRS width <120 ms): vagotonic manoeuvres adenosine or verapamil iv. DC (direct current) shock if patient is compromised Maintenance therapy: beta-blockers, verapamil.

Atrial fibrillation/flutter May be incidental finding. Beta-blockers for controling ventricular rate, digoxine is usefull in heart failure with AF.

Conversion of atrial fibrillation Within 48 hours from acute onset, propafenone 600 mg per os in patients without structural heart disease. Within 48 hours, amiodarone 300 mg per os in patients with structural heart disease.

Conversion of atrial fibrillation Immediate electrocardioversion: transesophageal echocardiography + 5000 IJ LMWH OR Electrocardioversion after 3 weeks of warfarin therapy.

Ekg.academy.com Atrial fibrillation Atrial flutter

Ventricular tachycardia (VT) Broad complex tachycardia (rate >100 bpm, QRS duration >120 ms) Acute management: amiodarone or lidocaine iv. Oral therapy: loading dose of amiodarone 200 mg every 8 hours for 7 days, 200 mg every 12 hours for next 7 days and maintenance therapy 200 mg a day.

Image source: Healio.com

Literature Oxford Handbook of Clinical Medicine. Longmore M. Wilkinson I. B. Baldwin A. Elizabeth W. Ninth edition. Wikipaedia.org Lifeinthefastlane.com Healio.com Ekg.academy.com