Heart failure with mid-range ejection fraction and with preserved ejection fraction

Heart Failure With Mid-range Ejection Fraction: A Distinctive Subtype or a Transitional Stage?

Heart failure with mid-range ejection fraction (HFmrEF) was first proposed by Lam and Solomon in 2014, and was listed as a new subtype of heart failure (HF) in 2016 European Society of Cardiology guidelines. Since then, HFmrEF has attracted an increasing amount of attention, and the number of related studies on this topic has grown rapidly. The diagnostic criteria on the basis of left ventricular ejection fraction (LVEF) are straightforward; however, LVEF is not a static parameter, and it changes dynamically during the course of HF. Thus, HFmrEF may not be an independent disease with a uniform pathophysiological process, but rather a collection of patients with different characteristics. HFmrEF is often associated with various cardiovascular and non-cardiovascular diseases. Thus, the pathophysiological mechanisms of HFmrEF are particularly complex, and its clinical phenotypes are diverse. The complexity and heterogeneity of HFmrEF may be one reason for inconsistent results between clinical studies. In fact, whether HFmrEF is a distinctive subtype or a transitional stage between HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF) is controversial. In this review, we discuss the clinical characteristics, treatment and prognosis of patients with HFmrEF, as well as the differences among HFmrEF, HFrEF, and HFpEF.

Heart Failure With Midrange Ejection Fraction-What Is It, If Anything?

The patient cohort with left ventricular ejection fractions (LVEFs) of 41%-49%, which has been defined as heart failure with midrange ejection fraction (HFmrEF), represent a significant proportion of the heart failure (HF) population. Despite the clear cutoffs established by different society guidelines, confusion remains regarding the exact significance of midrange LVEF within the HF syndrome. Patients with LVEF 41%-49% represent a heterogeneous group of patients sharing pathophysiologic mechanisms, biomarker profiles, comorbidities, and clinical characteristics with patients with preserved and reduced LVEF. In this clinical review, we discuss the underlying pathophysiologic mechanisms that culminate in the clinical syndrome of HF and contribute to the disparities observed between HFpEF, HFrEF, and HFmrEF. We highlight differences and similarities in clinical characteristics and imaging features between HFpEF and HFrEF in an effort to disentangle the heterogeneous group of patients with midrange LVEF, but ultimately we conclude that LVEF should be seen as simply one important element of a continuum throughout the HF syndrome, and that although is useful, it is an oversimplification, because HF syndrome is more of a continuum. The underlying pathophysiology, etiology, and comorbidities of patients presenting with HF is becoming ever more important as the limitations of a classification solely based on LVEF are being better recognised, and as patient-specific personalisation of care is becoming ever more important.

Range Variability in CMR Feature Tracking Multilayer Strain across Different Stages of Heart Failure

Heart failure (HF) is associated with progressive ventricular remodeling and impaired contraction that affects distinctly various regions of the myocardium. Our study applied cardiac magnetic resonance (CMR) feature tracking (FT) to assess comparatively myocardial strain at 3 distinct levels: subendocardial (Endo-), mid (Myo-) and subepicardial (Epi-) myocardium across an extended spectrum of patients with HF. 59 patients with HF, divided into 3 subgroups as follows: preserved ejection fraction (HFpEF, N = 18), HF with mid-range ejection fraction (HFmrEF, N = 21), HF with reduced ejection fraction (HFrEF, N = 20) and a group of age- gender- matched volunteers (N = 17) were included. Using CMR FT we assessed systolic longitudinal and circumferential strain and strain-rate at Endo-, Myo- and Epi- levels. Strain values were the highest in the Endo- layer and progressively lower in the Myo- and Epi- layers respectively, this gradient was present in all the patients groups analyzed but decreased progressively in HFmrEF and further on in HFrEF groups. GLS decreased with the severity of the disease in all 3 layers: Normal > HFpEF > HFmrEF > HFrEF (Endo-: −23.0 ± 3.5 > −20.0 ± 3.3 > −16.4 ± 2.2 > −11.0 ± 3.2, p < 0.001, Myo-: −20.7 ± 2.4 > −17.5.0 ± 2.6 > −14.5 ± 2.1 > −9.6 ± 2.7, p < 0.001; Epi-: −15.7 ± 1.9 > −12.2 ± 2.1 > −10.6 ± 2.3 > −7.7 ± 2.3, p < 0.001). In contrast, GCS was not different between the Normal and HFpEF (Endo-: −34.5 ± 6.2 vs −33.9 ± 5.7, p = 0.51; Myo-: −21.9 ± 3.8 vs −21.3 ± 2.2, p = 0.39, Epi-: −11.4 ± 2.0 vs −10.9 ± 2.3, p = 0.54) but was, as well, markedly lower in the systolic heart failure groups: Normal > HFmrEF > HFrEF (Endo-: −34.5 ± 6.2 > −20.0 ± 4.2 > 12.3 ± 4.2, p < 0.001; Myo-: −21.9 ± 3.8 > −13.0 ± 3.4 > −8.0 ± 2.7. p < 0.001; Epi-: −11.4 ± 2.0 > −7.9 ± 2.3 > −4.5 ± 1.9. p < 0.001). CMR feature tracking multilayer strain assessment identifies large range differences between distinct myocardial regions. Our data emphasizes the importance of sub-endocardial myocardium for cardiac contraction and thus, its predilect role in imaging detection of functional impairment. CMR feature tracking offers a convenient, readily available, platform to evaluate myocardial contraction with excellent spatial resolution, rendering further details about discrete areas of the myocardium. Using this technique across distinct groups of patients with heart failure (HF), we demonstrate that subendocardial regions of the myocardium exhibit much higher strain values than mid-myocardium or subepicardial and are more sensitive to detect contractile impairment. We also show comparatively higher values of circumferential strain compared with longitudinal and a higher sensitivity to detect contractile impairment. A newly characterized group of patients, HF with mid-range ejection fraction (EF), shows similar traits of decompensation but has relatively higher strain values as patients with HF with reduced EF.

Altered signature of apoptotic endothelial cell-derived microvesicles predicts chronic heart failure phenotypes

Aim: to evaluate the associations between signatures of apoptotic endothelial cell-derived microvesicles (MVs) with phenotypes of chronic heart failure (HF). Methods: The study cohort consisted of 388 prospectively involved subjects with HF patients with predominantly reduced left ventricular ejection fraction (HFrEF), HF with preserved ejection fraction (HFpEF) and HF with mid-range ejection fraction (HFmrEF). All biomarkers were measured at baseline. Results: The number of circulating CD31+/annexin V+ MVs in HFrEF and HFmrEF patients was similar. The number of circulating CD144+/annexin V+ MVs in HFrEF patients was significantly higher than HFmrEF and HFpEF. We determined that a combination of number of circulating CD31+/annexin V+ MVs and Gal-3 was the best predictor of HFpEF and that number of circulating CD144+/annexin V+ MVs is able to increase predictive capabilities of soluble ST2 (sST2) and Gal-3 for HFrEF. Conclusion: We found that the number of circulating CD31+/annexin V+ MVs may improve a predictive capacity for conventional HF biomarkers.