Adult Medical Emergency Handbook - Scottish Intensive Care Society

i
4. For acute treatment use ALS guidelines
BROAD COMPLEX ARRHYTHMIAS
VENTRICULAR PREMATURE BEATS - VPBs
Ventricular premature beats occurring in the early phase of acute
myocardial infarction, are common and are not in themselves predictors
of serious ventricular arrhythmias. However, in the presence of frequent
VPBs combined with significant left ventricular impairment (ejection
fraction 120 bpm. Differentiation between VT and
SVT with a bundle branch block is aided by the diagnostic algorithm.
Diagnosis
• Where possible compare previous ECGs in sinus or previous arrhythmia.
• In a patient with previous myocardial infarction, IHD,
cardiomyopathy, age >60 years, a broad complex tachycardia is
nearly always ventricular in origin.
• Adenosine may be used in an effort to assist diagnosis.
Do not use verapamil if VT is not excluded. It can cause
haemodynamic collapse or asystole.
Management
• See algorithms
• Treatable factors should be identified e.g. persistent cardiac
failure, hypokalaemia, hypomagnesaemia.
• Pro-arrhythmic effect of anti-arrhythmic drugs or inotropic agents
may necessitate their reduction or cessation.
• Occasionally mechanical causes are responsible e.g. central lines
or pacing wires.
adult medical emergencies handbook | NHS LOTHIAN: UNIVERSITY HOSPITALS DIVISION | 2009/11
121