Out-of-Proportion Pulmonary Hypertension and Heart Failure with Preserved Ejection Fraction

BACKGROUND: A subset of patients with heart failure with preserved ejection fraction (HFpEF) will have a marked increase in pulmonary artery pressure (PAP). OBJECTIVE: To evaluate the clinical and hemodynamic characteristics of these patients in comparison to patients with idiopathic pulmonary arterial hypertension (IPAH). METHODS: We reviewed the clinical and hemodynamic data of patients with HFpEF with out-of-proportion pulmonary hypertension (HFpEF-PH) and compared it to the corresponding data of age-matched patients with IPAH. RESULTS: Twenty consecutive patients with HFpEF-PH and 20 patients with IPAH were included in the study. The mean age (±SD) was 71.3 ± 7.8 and 70.2 ± 6.7 years, respectively. The majority of the HFpEF-PH patients were postmenopausal females with at least two features of the metabolic syndrome and atrial fibrillation. Although HFpEF-PH patients fulfilled the criteria for out-of-proportion PH, with transpulmonary gradient (TPG) >12 mm Hg, the difference between the diastolic PAP and the pulmonary capillary wedge pressure (PCWP) was significantly lower compared to IPAH (6.3 ± 6.2 vs. 27.5 ± 4.8, p < 0.00001). CONCLUSIONS: Our results suggest that a diagnosis of HFpEF-PH should be suspected when severe PH occurs in an elderly postmenopausal female with one or more features of the metabolic syndrome and atrial fibrillation. Interestingly, these patients had significantly lower differences between diastolic PAP and PCWP, suggesting that the increase in TPG is mainly caused by an elevated systolic PAP, possibly as a result of increased pulmonary vascular stiffness, and not pulmonary vascular remodeling.