Evidence-based On-call

Congestive heart failure

Clinical features

Ask about coronary artery disease ^a

- particularly a previous myocardial infarction ^b

Why?

Coronary artery disease makes left ventricular failure more likely

Patient	Target Disorder and Reference Standard	Diagnostic Test	LR+ (95% CI)	Post-test Probability	LR- (95% CI)	Post-test Probability
suspected heart failure ^a (pre-test probability: 6%)	LV ejection fraction < 50% (echocardiogram)	coronary heart disease	2.0 (1.5 to 2.6)	77%	0.60 (0.51 to 0.72)	51%

A previous MI increases the risk of left ventricular systolic failure

Patient	Target Disorder and Reference Standard	Diagnostic Test	LR+ (95% CI)	Post-test Probability	LR- (95% CI)	Post-test Probability
suspected heart failure ^b (pre-test probability: 17%)	left ventricular systolic failure (echocardiogram)	myocardial infarction	4.1 (2.7 to 6.2)	44%	0.48 (0.33 to 0.70)	8%