Covers acute and long-term treatment of supraventricular arrhythmias, starting with vagal manoeuvres, adenosine and other IV agents for regular narrow-QRS tachycardia, then a table of long-term options by arrhythmia type. It also addresses pre-excited AF, atrial flutter, and an AF-CARE approach to atrial fibrillation with its stroke risk score, anticoagulant dosing table, bleeding risk scheme and rate and rhythm control drugs. A short section ends on supraventricular bradyarrhythmias.
Topic 30 of 139 in the MU Sofia syllabus for Internal Diseases and Therapy (Medicine, Years 4 and 5). The free AceMed note covers it in 6 sections, about 1,105 words (10 min of reading), with 14 flashcards.
In this note
Reminders
Acute treatment of a regular narrow-QRS tachycardia
Long-term treatment by arrhythmia
Atrial flutter
Atrial fibrillation: the AF-CARE approach (ESC 2024)
Supraventricular bradyarrhythmias (in short)
Reminders
Goals: end the attack, prevent recurrences, control the ventricular rate, and in atrial fibrillation (AF) and flutter prevent stroke. Always look for and treat a cause (thyrotoxicosis, hypokalaemia, infection, hypoxia, drugs).
Guidelines: European Society of Cardiology (ESC) 2019 supraventricular tachycardia (SVT); ESC 2024 AF.
Acute treatment of a regular narrow-QRS tachycardia
Vagal manoeuvres first, with electrocardiogram (ECG) monitoring: modified Valsalva — strain against a closed glottis (about 40 mmHg) for 15 s half-sitting, then lie flat with the legs raised; carotid sinus massage 5–10 s on one side (not with a carotid bruit or previous stroke or transient ischaemic attack); cold water on the face.
Adenosine 6 mg rapid intravenous (IV) bolus into a large antecubital vein with a 20 mL saline flush; if no effect 12 mg, then up to 18 mg. Half-life < 10 s; record a rhythm strip — it ends AVNRT and AVRT and unmasks flutter or atrial tachycardia.
Use 3 mg via a central line, after heart transplant, or with dipyridamole; theophylline and caffeine blunt the effect.
Side effects: flushing, chest tightness, dyspnoea, a sense of doom, brief asystole, may trigger AF. Avoid in severe asthma, sick sinus syndrome and high-grade AV block without a pacemaker.
If adenosine fails or is contraindicated: verapamil 5–10 mg IV over 2 min (0.075–0.15 mg/kg) or diltiazem 0.25 mg/kg IV over 2 min; or a beta-blocker — metoprolol 2.5–5 mg IV, repeated to 15 mg, or esmolol 0.5 mg/kg then 0.05–0.3 mg/kg/min.
Still not terminated → synchronised DC cardioversion.
Never give verapamil or diltiazem in a broad-QRS tachycardia, heart failure with reduced ejection fraction or pre-excitation — risk of collapse. Treat an unclear broad-complex tachycardia as ventricular tachycardia.
Continue reading free
The whole note, all 6 sections, is free with an AceMed account, with its 14 flashcards. Premium adds flashcard recall, highlights and Ask AI.
