Diagnostic accuracy of clinical criteria for identifying systolic and diastolic heart failure: cross-sectional study

To determine the validity and clinical usefulness of clinical criteria in the diagnosis of systolic and diastolic heart failure. Cross-sectional diagnostic study. 216 patients admitted consecutively to the cardiology section of an academic hospital with a suspected diagnosis of heart failure in a period of 12 months. A definite diagnosis of heart failure (echocardiographic diagnostic criteria of left ventricular dysfunction) was cross-matched with the results obtained using the test under investigation (Framingham clinical diagnostic criteria for heart failure). Sensitivity, specificity, positive predictive value, negative predictive value, likelihood ratio for positive test result (LR+) and likelihood ratio for negative test result (LR-) were calculated and used to construct clinical decision-making diagrams. The Framingham clinical criteria are very sensitive (92%) and moderately specific (79%). The diagnosis of heart failure was ruled out with a good LR- (0.1) but the diagnosis was confirmed with only a low level of evidence as the LR+ was 4.3. The main difference found between systolic and diastolic heart failure is that in the case of systolic failure the disease is ruled out conclusively (0.04), whereas in the case of diastolic failure the change in probability generated is at the borderline between conclusive and moderate (0.1). The absence of the Framingham clinical criteria rules out the diagnosis of heart failure, particularly in the case of systolic heart failure. However, the presence of these criteria do not necessarily confirm the diagnosis, which may be based in echocardiography.