Cardiac Magnetic Resonance Imaging in Heart Failure With Preserved Ejection Fraction.

Heart failure with preserved ejection fraction (HFpEF) is a complex syndrome characterized by left ventricular diastolic dysfunction, elevated filling pressures, and normal ejection fraction (left ventricular ejection fraction ≥50%) in the absence of an underlying disease process. Its prevalence is increasing, driven by an aging population and rising comorbidities including obesity, diabetes, and hypertension. Given the benefit of emerging HFpEF therapies, such as glucagon-like peptide-1 inhibitors, early and accurate diagnosis is critical to improve outcomes. The diagnosis of HFpEF, however, can be challenging to make, and clinical practice relies heavily on echocardiographic evidence of diastolic dysfunction. There is a need for additional noninvasive diagnostic strategies to facilitate earlier HFpEF diagnosis to improve clinical outcomes. Emerging evidence suggests that cardiac magnetic resonance (CMR) imaging may have clinical value in enhancing HFpEF diagnosis and prognosis. Moreover, CMR tissue characterization by parametric mapping sequences (T1/T2 mapping and extracellular volume quantification) makes CMR a powerful tool for evaluating HFpEF mimickers, specific diseases that cause the clinical syndrome of heart failure in the setting of normal ejection fraction, which may confound HFpEF diagnosis. Finally, novel imaging sequences, such as magnetic resonance spectroscopy, diffusion tensor imaging, and elastography, are being developed to characterize metabolism and hemodynamics in vivo and may provide insight into HFpEF pathophysiology. The diagnostic and prognostic values of CMR-derived indices of diastolic dysfunction and the use of CMR to distinguish between HFpEF and its mimickers, as well as the use of novel CMR sequences in HFpEF, are reviewed herein.