Abstract 18283: Left Ventricular STIFFness vs. Fibrosis Quantification by T1 MAPping in Heart Failure With Preserved Ejection Fraction - STIFFMAP-HFpEF
Introduction: Heart Failure with Preserved Ejection Fraction (HFpEF) is an increasing public health problem. To tailor successful treatment strategies it is essential to identify patients’ individual pathologies contributing to HFpEF. Cardiac magnetic resonance (CMR) derived T1-Mapping has been suggested as non-invasive tool to quantify diffuse myocardial fibrosis. Invasive tracings of pressure-volume relations represent the gold-standard for assessing load-independent mechanical diastolic properties of the left ventricle.
Hypothesis: Aim of this study was therefore to elucidate the diagnostic performance of T1-Mapping in HFpEF patients by examining the relationship between the extracellular volume fraction (ECV) and invasively measured parameters of diastolic function and to study the potential of ECV to differentiate between different pathomechanisms in HFPEF.
Methods: We performed CMR T1-Mapping in 21 patients with HFpEF and 11 patients without heart failure symptoms (further referred to as controls). Pressure volume loops were obtained with a conductance catheter during basal conditions and handgrip exercise. Transient preload reduction was used to extrapolate the diastolic stiffness constant.
Results: Patients with HFpEF showed a higher extra cellular volume fraction (p=0.001), an elevated load-independent passive LV stiffness constant - ß (p<0.001) and a longer time constant of active LV-relaxation Tau (p=0.04). ECV correlated well with ß (r =0.75, p <0.001). After multivariate analysis, ECV remained the only independent predictor of ß.
Within the HFpEF cohort, patients with ECV over median showed higher left ventricular masses (p=0.04) and a higher LV stiffness (p=0.05). ECV < median identified patients with a prolonged active LV relaxation (p=0.008) and a marked hypertensive reaction to exercise due to a pathologic arterial elastance (p=0.05).
Conclusions: Diffuse myocardial fibrosis, assessed by CMR derived T1-Mapping independently predicts invasively measured LV stiffness in HFpEF. In addition, ECV helps to non-invasively distinguish the role of impaired active relaxation and passive stiffness and refines characterization of patients, which represents a prerequisite for any successful therapy in the future.
Author Disclosures: K. Rommel: None. M. von Roeder: None. T. Stiermaier: None. K. Latuscynski: None. C. Oberueck: None. M. Sandri: None. C. Lücke: None. M. Gutberlet: None. G. Schuler: None. P. Lurz: None.
- © 2015 by American Heart Association, Inc.