Abstract 14879: Heart Failure With Preserved Ejection Fraction Patients Do Not Augment Longitudinal Pumping During Exercise

Abstract

Introduction: Left ventricular (LV) pumping from longitudinal motion is highly efficient and a major contributor to stroke volume (SV). Patients with heart failure with preserved ejection fraction (HFpEF) have diminished longitudinal ventricular motion but the effect on LV pumping is unknown. This study aimed to determine the contribution of longitudinal pumping in HFpEF compared to healthy age-matched controls at rest and submaximal exercise when exercise induced SV reserve is maximal. Methods: Cardiopulmonary exercise testing with concurrent 3D echocardiography was performed in 30 subjects (HFpEF n = 20, age 69±5 years, Senior Control (CON): n = 10, age 70±4 years) at rest and during exercise at a targeted heart rate of 100 bpm (HFpEF 66±18% VO 2 Max, CON: 49±13% VO 2 Max, p = 0.014). LV volumes and mitral annular excursion (MAE), a novel metric of systolic function, were measured using multi-beat 3D acquisition at rest and during sub-maximal exercise. MAE volume (MAEV) was measured by multiplying MAE by short axis area at the base of the ventricle. Relative longitudinal pumping was calculated as the quotient of MAEV and SV (%). Results: Mitral annular excursion (MAE) at rest was lower in HFpEF (Figure) and increased significantly less during sub-maximal exercise compared to controls (CON Δ3.3mm vs HFpEF Δ1.1mm, group p = 0.002, group x exercise p = 0.011). MAEV was similar in HFpEF compared to controls at reest but did not augment in HFpEF compared to controls (CON Δ7.1 ml vs HFpEF Δ1.9 ml, group x exercise p = 0.002). Relative longitudinal pumping increased significantly with exercise in CON but remained unchanged in HFpEF (CON Δ7.9% vs HFpEF Δ-0.7%, group x exercise p = 0.043). Conclusions: Longitudinal pumping does not increase in HFpEF patients despite exercising at a higher relative metabolic demand than their healthy peers. This lack of longitudinal pumping reserve may contribute to and help identify cardiac limitations during exercise commonly seen in HFpEF patients.