Author: Reddy YNV et al.
Circulation 2018 May 23
A 10-point risk score based on noninvasive characteristics might be helpful in identifying patients who need further testing.
Establishing the diagnosis of heart failure (HF) in people presenting with dyspnea can be challenging when they lack corroborative structural abnormalities like reduced left ventricular ejection fraction (LVEF) or clinically apparent volume overload. In a single-site study, researchers assessed noninvasive characteristics associated with HF; the reference standard was invasive hemodynamic exercise test results.
Study participants were 414 consecutive people with preserved LVEF and without significant underlying functional or structural cardiac abnormalities and no evidence of volume overload at rest who underwent invasive exercise testing for unexplained dyspnea. Of the participants, 267 were found to have HF (pulmonary capillary wedge pressure, ≥15 mm Hg at rest or ≥25 mm Hg during exercise). Based on a multivariable analysis including baseline clinical characteristics, laboratory testing, and imaging parameters, the investigators developed an “H2FPEF” risk score, ranging from 0 to 9 points:
Heavy (body-mass index, >30 kg/m2, 2 points),
Hypertension (≥2 medications for hypertension, 1 point);
Atrial Fibrillation (paroxysmal or persistent, 3 points);
Pulmonary hypertension (pulmonary artery systolic pressure, >35 mm Hg by echocardiography, 1 point);
Elder (age, >60, 1 point)
Elevated Filling pressure (Doppler E/e’ ratio >9, 1 point).
Each point increased HF odds by a factor of 2. The score had excellent discrimination (area under the curve, 0.841) and performed well in a validation cohort of 100 individuals.
Invasive exercise testing is rarely performed for unexplained dyspnea. Thus, the H2FPEF risk score would benefit from external validation because of the potential for referral bias in these patients. Further, natriuretic peptide levels were missing in nearly 25% of the population, which could explain absence of this measure from the risk score. Nevertheless, the risk score performed strongly and has face validity. An intermediate score might usefully indicate that an individual would benefit from additional testing to clarify the contribution of HF to unexplained dyspnea.