Investigations

• MRI ^a  

Why?

MRI can diagnose and exclude aortic dissection

Patient	Target Disorder and Reference Standard	Diagnostic Test	LR+ (95% CI)	Post-test Probability	LR- (95% CI)	Post-test Probability
suspected aortic dissection a (pre-test probability: 55%)	aortic dissection (aortography, surgery, or autopsy)	MRI	45 (6.5 to 310)	98%	0.017 (0.013 to 0.022)	2%

Note:

• MRI takes longer than echocardiography (on average 10 minutes longer) ^a
• MRI may not be practical in ventilated patients or patients requiring extensive monitoring. ^d