Transvenous Electrical Cardioversion
What means TVEC?
Transvenous Electrical Cardioversion (TVEC) is a specialised cardiac procedure designed to restore normal sinus rhythm by delivering a controlled electrical impulse directly within the heart via intravascular catheters.
TVEC is considered one of the most effective and predictable treatments for atrial fibrillation in horses, with reported success rates exceeding 90%
Atrial Fibrillation in Horses
Atrial fibrillation (AF) is a cardiac rhythm disorder characterised by a loss of coordinated atrial contraction. In horses, it commonly leads to poor performance, reduced exercise tolerance and abnormal heart rhythm during work, while signs at rest may remain subtle.
Diagnosis is based on electrocardiography (ECG) and completed by cardiac imaging, including echocardiography.
Why do we Treat Atrial Fibrillation?
In performance horses, atrial fibrillation limits cardiac efficiency and athletic capacity and may pose safety concerns during intense exercise. Restoring normal sinus rhythm is therefore the primary therapeutic objective.
How works this procedure ?
A complete cardiac evaluation is performed prior to the procedure
Under general anaesthesia, cardioversion catheters are introduced via the jugular vein and positioned close to the atria
A synchronised electrical shock is delivered under ECG guidance to restore normal rhythm
The horse is carefully monitored during recovery and in the following period
Because the electrical energy is delivered directly inside the heart, lower energy levels are required compared to external cardioversion.
Advantages and Prognosis
High success rate in restoring sinus rhythm
Avoids the use of anti-arrhythmic drugs and their potential side effects
Allows most horses to return to athletic activity following appropriate recovery and follow-up
Long-term outcome is generally favourable, although recurrence may occur depending on individual cardiac factors.
