The role of pulmonary function in patients with heart failure and preserved ejection fraction: Looking beyond chronic obstructive pulmonary disease

Abstract

Background: The prognostic value of chronic obstructive pulmonary disease (COPD) as a comorbidity in heart failure has been well documented. However, the role of pulmonary function indices in patients with heart failure and preserved ejection fraction (HFpEF) remains to be elucidated.

Methods: Subjects with HFpEF received pulmonary function tests and echocardiogram. Total lung capacity (TLC), residual volume (RV), forced expiratory flow rate between 25% and 75% of vital capacity (FEF25-75), forced expiratory volume in the 1st second (FEV1), forced vital capacity (FVC), and vital capacity (VC) were measured. Echocardiographic indices, including pulmonary artery systolic pressure (PASP), the ratio of early ventricular filling flow velocity to the septal mitral annulus tissue velocity (E/e'), and left ventricular mass (LVM), were recorded. National Death Registry was linked for the identification of mortality.

Results: A total of 1194 patients (72.4±13.2 years, 59% men) were enrolled. PASP, E/e' and LVM were associated with either obstructive (RV/TLC, FEV1 and FEF25-75) or restrictive (VC and TLC) ventilatory indices. During a mean follow-up of 23.0±12.8 months, 182 patients died. Subjects with COPD had a lower survival rate than those without COPD. While VC, FVC, RV/TLC, and FEV1 were all independently associated with all-cause mortality in patients without COPD, only FEF25-75 was predictive of outcomes in those with COPD.

Conclusions: The abnormalities of pulmonary function were related to the cardiac hemodynamics in patients with HFpEF. In addition, these ventilatory indices were independently associated with long-term mortality, especially in those without COPD.

Conflict of interest statement

The authors have declared that no competing interests exist.

Figures

Fig 1. The flow chart of the study population.

Fig 2. The distributions of the pulmonary function abnormalities.

The severity of obstructive ventilation defect was graded according to the predicted %FEV1 (mild >80%; moderate 50–80%; severe 30–50%; or very severe 80%; mild 70–80%; moderate 50–70%; severe/very severe

Fig 3. The Kaplan–Meier survival curve analysis of the study population, stratified by the presence of chronic obstructive pulmonary disease.

Fig 4. The prevalence of high left ventricular end-diastolic pressure (LVEDP) and pulmonary hypertension, according to the quartile distributions of the predicted %FEV1 (>93%, 77–93%, 60–77%, and 99%, 87–99%, 77–87%, and