Saddle Thrombus seen on Transthoracic Echo: A Rare Feature in Pulmonary Embolism

Abstract

The Saddle thrombus is a rare condition characterized by presence of a large thrombus
which straddles the main pulmonary arterial trunk and its bifurcation leading to acute massive
Pulmonary Embolism (PE). Its incidence among patients diagnosed with PE is approximately
2.6%.1 Saddle PE frequently results in significant hemodynamic instability and signals the potential
for imminent hemodynamic collapse. This is rarely seen on Trans-thoracic echocardiography
(TTE). We recently came across a patient who presented with breathlessness following
transatlantic air travel. His TTE (routine and 3D) revealed a saddle thrombus in the main pulmonary
arterial trunk extending into its two main branches (Figures 1 and 2). A CT pulmonary
angiogram confirmed the same (Figure 3). He was subsequently successfully thrombolyzed and
made an uneventful recovery.