Persistent left superior vena cava in a man with ventricular fibrillation.

Area of Science:

• Cardiology
• Cardiac Electrophysiology
• Congenital Heart Disease

Background:

• Sudden cardiac arrest (SCA) and recurrent syncope are critical clinical events.
• Ventricular fibrillation (VF) is a primary cause of SCA.
• Congenital heart abnormalities can predispose individuals to arrhythmias.

Observation:

• A patient presented with recurrent syncope and sudden cardiac arrest.
• The patient had ventricular fibrillation unrelated to acute myocardial infarction.
• Electrophysiologic study revealed an isolated left superior vena cava (LSVC).

Findings:

• Programmed ventricular stimulation readily induced ventricular fibrillation (VF).
• VF induction occurred both off and during serial electropharmacologic testing.
• These results establish a link between LSVC and inducible VF.

Implications:

• Isolated left superior vena cava may be an independent risk factor for sudden cardiac death.
• This finding highlights the importance of considering congenital anomalies in unexplained ventricular arrhythmias.
• Further research into the arrhythmogenic mechanisms of LSVC is warranted.