Am Fam Physician. 2019;99(10):online
Which patients with unexplained dyspnea are more likely to have heart failure with preserved ejection fraction (HFPEF [diastolic heart failure]) as the cause?
A simple clinical prediction rule using noninvasive data can identify patients at low, moderate, and high risk for HFPEF. Although validated in a separate group of patients, the validation group was from the same center, so prospective validation should still be performed in a separate population by another group of investigators. (Level of Evidence = 2b)
The authors identified patients who had been referred to the Mayo Clinic for unexplained dyspnea and underwent invasive testing. The reference standard was right-sided coronary catheterization, with measurement of pressures at rest and, if necessary, during exercise. Predictors were ascertained by chart review. This is ordinarily a red flag, but in this case the predictors were relatively unambiguous (e.g., body mass index, number of medications for hypertension) and the chart review was done in parallel by two investigators using clear prespecified definitions for each variable. The derivation population consisted of 414 consecutive patients, 64% of whom had HFPEF. The validation population was 100 consecutive patients at the same center, with a prevalence of HFPEF of 61%. The mean age of participants was 56 years for those with noncardiac dyspnea and 68 years for those with HFPEF; 60% were women. Logistic regression was used to identify independent predictors, and points were assigned to each predictor based on the beta-coefficient. The independent predictors were body mass index greater than 30 kg per m2 (2 points), taking two or more antihypertensive drugs (1 point), paroxysmal or persistent atrial fibrillation (3 points), Doppler echocardiogram with pulmonary artery systolic pressure greater than 35 mm Hg, 60 years or older, and Doppler echocardiogram showing an E/e ratio of more than nine. In the validation group, the observed proportion with HFPEF ranged from 0% with 0 points to more than 90% with at least 6 points. The authors suggest that the diagnosis can be provisionally ruled out for patients with 0 or 1 point, ruled in for patients with more than 5 points, and that further testing is needed for those with 2 to 5 points.
Study design: Decision rule (validation)
Funding source: Government
Setting: Outpatient (specialty)
Reference:ReddyYNCarterREObokataMRedfieldMMBorlaugBAA simple, evidence-based approach to help guide diagnosis of heart failure with preserved ejection fraction. Circulation2018;138(9):861–870.