cardiac right to left shunt

Introduction

See congenital heart disease

Etiology

• patent foramen ovale (38%)
• pulmonary arteriovenous malformation (28%)
• 5% with both
• Eisenmenger's syndrome
• No association of shunting with migraine

Epidemiology

• 71% of healthy volunteers have some right-to-left shunting
• shunt size mostly 'small to moderate'

Laboratory

• complete blood count: erythrocytosis
• pulse oximetry or arterial blood gas: hypoxia

Diagnostic procedures

• echocardiogram:
  • identified by saline contrast echocardiogram (bubble study)

Management

• consider air filters on intravenous lines in hospitalized patients to prevent paradoxical air embolism

More general terms

• cardiac shunt