Comprehensive Echocardiographic and Cardiovascular Magnetic Resonance Evaluation Differentiates Between Patients with Heart Failure with Preserved Ejection Fraction, Hypertensive Patients and Healthy Controls

Objectives: The aim of this study was to investigate the utility of a comprehensive imaging protocol including echocardiography and cardiovascular magnetic resonance (CMR) in the diagnosis and differentiation of hypertensive heart disease and heart failure with preserved ejection fraction (HFpEF).

Background: Hypertension is present in up to 90% of patients with HFpEF and is a major etiological component. Despite current recommendations and diagnostic criteria for HFpEF, no non-invasive imaging technique has as yet shown the ability to identify any structural differences between patients with hypertensive heart disease and HFpEF.

Methods: We conducted a prospective cross-sectional study of 112 well-characterised patients (62 with HFpEF, 22 with hypertension and 28 healthy controls). All patients underwent cardiopulmonary exercise and biomarker testing and an imaging protocol including echocardiography with speckle tracking analysis and CMR including T1 mapping pre- and post-contrast.

Results: Echocardiographic global longitudinal strain (GLS) and extracellular volume (ECV) measured by CMR were the only variables able to independently stratify between the three groups of patients. ECV was the best technique for differentiation between hypertensive heart disease and HFpEF (ECV AUC 0.88; GLS AUC 0.78, p<0.001 forboth). Using ECV, an optimal cut-off of 31.2% gave 100% sensitivity and 75% specificity. ECV was significantly higher and GLS was significantly reduced in subjects with reduced exercise capacity (lower peak VO2 and higher VE/VCO2) (p<0.001 for both ECV and GLS).

Conclusions: Both GLS and ECV are able to independently discriminate between hypertensive heart disease and HFpEF and identify patients with prognostically significant functional limitation. ECV is the best diagnostic discriminatory marker of HFpEF and could be used as a surrogate end-point for therapeutic studies.