Intra-study and inter-technique validation of cardiovascular magnetic resonance imaging derived left atrial ejection fraction as a prognostic biomarker in heart failure with preserved ejection fraction

Abstract

The aim of this study was to assess the agreements of both biplane and short-axis Simpson's (SAX) methods for left atrial ejection fraction (LAEF) calculation utilising cardiovascular magnetic resonance imaging (CMR) in heart failure with preserved ejection fraction (HFpEF) and evaluate their relation to clinical outcomes. One hundred and thirty six subjects (HFpEF n = 97, controls n = 39) underwent CMR, six-minute walk tests and blood sampling in our prospective, observational, single-centre study. Overall, LAEF (%) was lower in HFpEF patients compared to controls (SAX 34 ± 13 vs 47 ± 8, biplane 34 ± 16 vs 51 ± 11; p < 0.0001 for both). Atrial fibrillation (AF) was present in 24% of HFpEF and was associated with higher LA volumes and lower LAEF compared to sinus rhythm (p < 0.0001) with both methods. Biplane LAEF correlated strongly with SAX measurements (overall Pearson's r = 0.851, sinus rhythm r = 0.651, AF r = 0.882; p < 0.0001). Biplane LAEF did not differ significantly compared to SAX LAEF (overall 34 ± 16 vs 34 ± 13%; p = 0.307) except in AF subjects in whom biplane LAEF was lower (mean difference 2 ± 4%, p = 0.013). There were 44 composite events (25 deaths, 19 HF hospitalizations) in HFpEF during median follow-up of 1429 days. LAEF below the median was associated with increased risk of composite endpoints (Log-Rank biplane p < 0.0001; SAX p = 0.009). In multivariable Cox proportional hazards regression analysis, both biplane LAEF (hazard ratio [HR] 0.604; 95% confidence interval [CI] (0.406-0.900); p = 0.013) and SAX LAEF (HR 0.636; CI 0.441-0.918; p = 0.016) remained independent predictors along with indexed extracellular volume. CMR LAEF, derived from either the short-axis or biplane method is lower in HFpEF compared to healthy controls and remains a strong marker of prognosis.

Multi-modality assessment and role of left atrial function as an imaging biomarker in cardiovascular disease

“…LA volume indexed to body surface area forms an integral part of LV diastolic function assessment [7] and is an essential component for the diagnostic criteria for heart failure with preserve ejection fraction (HFpEF), previously referred to as diastolic heart failure [8][9][10]. LA function has also attracted considerable attention as a cardiovascular imaging biomarker due to its prognostic importance [11][12][13][14] and because functional abnormalities often precede adverse LA structural remodelling and overt clinical disease [9, [15][16][17][18][19].…”

Prevalence of right ventricular dysfunction and prognostic significance in heart failure with preserved ejection fraction

“…The CMR protocol used has been reported previously [ 11 , 14 , 15 ]. All scans were performed on a 3 T scanner (Siemens Skyra, Erlangen, Germany) with an 18-channel cardiac coil.…”

Microvascular Dysfunction in Heart Failure with Preserved Ejection Fraction: Pathophysiology, Assessment, Prevalence and Prognosis

“…right ventricular dysfunction, LA dysfunction, focal and diffuse myocardial fibrosis) known to influence prognosis. [9][10][11]60 CMR also permits quantitative perfusion assessment with greater spatial resolution than that of PET. In a study of 19 patients with symptomatic HFpEF (LVEF threshold >45%) and in whom LV hypertrophy was absent and CAD excluded by CT coronary angiography, MVD (defined as MPR <2.5) was present in the most (13/19).…”