CT chest with contrast is the recommended modality, but repeat testing may be needed for eventual diagnosis 
Endoscopy may be considered, but may be associated an increased risk of clinical deterioration
Transthoracic and transesophageal echocardiography have not been found to be highly sensitive
Atrio-esophageal fistula
Sepsis
Subglottic stenosis
Stroke/TIA
Tracheomalacia
GI bleed
Esophageal injury
Acute coronary syndromes 