Basic calculations
Tachycardia with a pulse
Follows the AHA 2025 and ERC 2025 adult tachycardia algorithms side by side. Unstable patients get synchronised cardioversion with the energy for the rhythm. Stable patients are treated by QRS width and regularity: modified Valsalva and adenosine for regular narrow-complex tachycardia, rate control for AF, amiodarone or procainamide for presumed VT, magnesium for torsades de pointes, and no AV-nodal blockers in pre-excited AF.
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Adverse features
Caused by the tachycardia (usually HR ≥ 150 bpm)
12-lead ECG
Tachycardia with a pulse
Stable
Regular narrow-complex: SVT (AVNRT, AVRT), atrial flutter or atrial tachycardia
Drug therapy guided by the ECG
- ⚠ Give oxygen if hypoxic, get IV access and record a 12-lead ECG before treatment whenever possible.
Treatment
ESC
- Vagal manoeuvres: modified ValsalvaIERC 2025Strain against a closed glottis (blow into a 10 mL syringe) for 15 s semi-recumbent, then lie flat and raise the legs to 45° for 15 s (REVERT). Record a rhythm strip.
- Adenosine 6 mg rapid IV, then 12 mg, then 18 mgIERC 2025Record the ECG during each dose; flutter waves may be unmasked.
- If adenosine fails or is contraindicated: verapamil, diltiazem or a beta-blockerIIaERC 2025Verapamil 2.5–5 mg IV over 2 min (avoid in HFrEF), diltiazem 15–20 mg IV, or metoprolol 2.5–5 mg IV. Synchronised cardioversion if drugs fail.
AHA 2025
- Vagal manoeuvres: modified ValsalvaIAHA 2025Strain against a closed glottis (blow into a 10 mL syringe) for 15 s semi-recumbent, then lie flat and raise the legs to 45° for 15 s (REVERT). Record a rhythm strip.
- Adenosine 6 mg rapid IV push, then 12 mgIAHA 2025Large proximal vein with a 20 mL flush; record the ECG during the dose. Warn the patient about transient chest discomfort. Lower dose (3 mg) with a heart transplant, central line, dipyridamole or carbamazepine.
- If adenosine fails or is contraindicated: verapamil, diltiazem or a beta-blockerIIaAHA 2025Verapamil 2.5–5 mg IV over 2 min (avoid in HFrEF), diltiazem 15–20 mg IV, or metoprolol 2.5–5 mg IV. Synchronised cardioversion if drugs fail.
References
- American Heart Association. 2025 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Part 9: Adult advanced life support. Circulation 2025;152(suppl 2).
- European Resuscitation Council Guidelines 2025: Adult advanced life support. Resuscitation 2025.
- Brugada J, et al. 2019 ESC Guidelines for the management of patients with supraventricular tachycardia. Eur Heart J 2020;41:655-720.
- Zeppenfeld K, et al. 2022 ESC Guidelines for ventricular arrhythmias and the prevention of sudden cardiac death. Eur Heart J 2022;43:3997-4126.
- Appelboam A, et al. Postural modification to the standard Valsalva manoeuvre for emergency treatment of supraventricular tachycardias (REVERT). Lancet 2015;386:1747-1753.
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