Real-time cardiovascular magnetic resonance imaging for non-invasive characterisation of heart failure with preserved ejection fraction: final outcomes of the HFpEF stress trial

Abstract

Background: The diagnosis of heart failure with preserved ejection fraction (HFpEF) remains challenging. Recently, the HFpEF Stress Trial demonstrated feasibility and accuracy of non-invasive cardiovascular magnetic resonance (CMR) real-time (RT) exercise-stress atrial function imaging for early identification of HFpEF. However, no outcome data have yet been presented.

Methods: The HFpEF Stress Trial (DZHK-17) prospectively recruited 75 patients with dyspnea on exertion and echocardiographic preserved EF and signs of diastolic dysfunction (E/e' > 8). 68 patients entered the final study cohort and were characterized as HFpEF (n = 34) or non-cardiac dyspnea (n = 34) according to pulmonary capillary wedge pressure (HFpEF: PCWP rest: ≥ 15 mmHg stress: ≥ 25 mmHg). These patients were contacted by telephone and hospital charts were reviewed. The clinical endpoint was cardiovascular events (CVE).

Results: Follow-up was performed after 48 months; 1 patient was lost to follow-up. HFpEF patients were more frequently compared to non-cardiac dyspnea (15 vs. 8, p = 0.059). Hospitalised patients during follow-up had higher H2FPEF scores (5 vs. 3, p < 0.001), and impaired left atrial (LA) function at rest (p ≤ 0.002) and stress (p ≤ 0.006). Impairment of CMR-derived atrial function parameters at rest and during exercise-stress (p ≤ 0.003) was associated with increased likelihood for CVE. CMR-Feature Tracking LA Es/Ee (p = 0.016/0.017) and RT-CMR derived LA long axis strain (p = 0.003) were predictors of CVE independent of the presence of atrial fibrillation.

Conclusions: Left atrial function emerged as the strongest predictor for 4-year outcome in the HFpEF Stress Trial. A combination of rest and exercise-stress LA function quantification allows accurate diagnostic and prognostic stratification in HFpEF.

Clinicaltrials: gov: NCT03260621.

Keywords: Atrial function; Deformation; Exercise-stress; HFpEF; Real-time cardiovascular magnetic resonance; Strain.

Fig. 1

Study Flow-Chart. HFpEF heart failure with preserved ejection fraction, CAD coronary artery disease, HCM hypertrophic cardiomyopathy, PA pulmonary artery pressure, PCWP pulmonary capillary wedge pressure

Fig. 2

Feature-tracking and strain analysis. Top: On the left, left atrial (LA) end-systolic (ES) and -diastolic (ED) 2 and 4 chamber views (CV) with endocardial border tracking using cardiovascular magnetic resonance feature-tracking (CMR-FT). On the right, the corresponding strain curve of left atrial reservoir (εs), conduit (εe) and booster pump (εa) function for A a HFpEF patient without and B with cardiovascular event during follow-up. Bottom: Left atrial and ventricular (LV) long axis strain (LAS) assessment on a real-time CMR sequences shown at timespoints of ES and ED

Fig. 3

Cardiovascular events during follow-up. The graph shows the percentage of patients with cardiovascular events (CVE) in patients with A H2FPEF score ≤ 4 and ≥ 5 points, B cardiovascular magnetic resonance imaging (CMR) derived left atrial long axis strain (LA LAS) at rest above or below the median, C speckle tracking echocardiography (STE) derived left atrial reservoir strain (Es) at rest above or below the median and D CMR-feature tracking (FT) derived left atrial reservoir strain (Es) at rest above or below the median

Fig. 4

Accuracy to predict cardiovascular events. The figure displays the accuracy to predict cardiovascular events as areas under the ROC curve (AUC) for the H2FPEF score as well as cardiovascular magnetic resonance imaging (CMR) derived left atrial (LA) long axis strain (LAS), speckle tracking echocardiography (STE) derived reservoir strain (Es) and CMR-derived Es at rest