AIMS: The REDUCE-LAP II trial demonstrated adverse outcomes after interatrial shunt device (IASD) placement in heart failure with preserved ejection fraction (HFpEF) attributed to latent pulmonary vascular disease (PVD). We hypothesized that exercise-stress cardiovascular magnetic resonance (CMR) imaging could provide non-invasive characterisation of cardiac and pulmonary physiology for improved patient selection.
METHODS AND RESULTS: The HFpEF-Stress Trial prospectively enrolled 75 patients with exertional dyspnoea and diastolic dysfunction. Patients underwent rest and exercise-stress right heart catheterisation (RHC), echocardiography and CMR imaging. Pulmonary artery and capillary wedge pressures, cardiac index (CI) and vascular resistance (PVR) were calculated. Latent PVD was defined as increased PVR≥1.74 Wood-Units during exercise-stress. CMR assessed long axis strains (LAS) and filling volumes of all cardiac chambers. Right ventricular (RV) function was further quantified by stroke and peak flow volumes. Patients with latent PVD (n = 24) showed lower RV function (rest TAPSE, p = 0.010; stress RV LAS, p < 0.001) compared to patients without (n = 43). During exercise-stress, RV stroke and peak flow volumes (p < 0.001) were reduced and led to impaired left atrial (p = 0.040) and with a strong statistical trend to impaired ventricular (LV) filling (p = 0.098). This subsequently resulted in reduced LV-CI (p < 0.001) despite preserved LV systolic function (LV LAS p ≥ 0.255). The degree of RV dysfunction during exercise-stress best predicted latent PVD (RV peak flow, AUC rest 0.73 vs. stress 0.89, p = 0.004).
CONCLUSIONS: Latent PVD is a feature of HFpEF and is associated with impaired RV functional reserve, global diastolic filling and LV-CI. This can be quantified by CMR and used to identify patients likely to benefit from IASD implantation.
Fields of Expertise
- Human- & Biotechnology