Syncope Due to Iatrogenic Cava Vein Obstruction: Rare Complication of Cardiac Implantable Electronic Device Leads.

A 77-year-old female patient with multiple pacemaker leads experienced hypotension and syncope during right heart catheterization. Imaging studies revealed a stenotic inferior vena cava with superior vena cava obstruction and well-developed retrograde collateral vessels, suggesting that balloon obstruction of the sole venous return site caused low cardiac output leading to syncope.