Heart failure patients with improved ejection fraction: Insights from the MECKI score database
Authors: Agostoni Piergiuseppe , Pluchinotta Francesca Romana , Salvioni Elisabetta , Mapelli Massimo , Galotta Arianna , Bonomi Alice , Magrì Damiano , Perna Enrico , Paolillo Stefania , Corrà Ugo , Raimondo Rosa , Lagioia Rocco , Badagliacca Roberto , Perrone Filardi Pasquale , Apostolo Anna , Senni Michele , Iorio Annamaria , Correale Michele , Campodonico Jeness , Palermo Pietro , Cicoira Mariantonietta , Metra Marco , Guazzi Marco , Limongelli Giuseppe , Contini Mauro , Pezzuto Beatrice , Sinagra Gianfranco , Parati Gianfranco , Cattadori Gaia , Carriere Cosimo , Cittar Marco , Matassini Maria Vittoria , Salzano Andrea , Cittadini Antonio , Masè Marco , Bandera Francesco , Bussotti Maurizio , Mattavelli Irene , Re Federica , Vignati Carlo , Lombardi Carlo , Scardovi Angela B. , Sciomer Susanna , Passantino Andrea , Emdin Michele , Di Lenarda Andrea , Passino Claudio , Santolamazza Caterina , Moscucci Federica , Zaffalon Denise , Piepoli Massimo ,   on behalf of the MECKI Score Research Group
Published: September 2023

Aims

Improvement of left ventricular ejection fraction is a major goal of heart failure (HF) treatment. However, data on clinical characteristics, exercise performance and prognosis in HF patients who improved ejection fraction (HFimpEF) are scarce. The study aimed to determine whether HFimpEF patients have a distinct clinical phenotype, biology and prognosis than HF patients with persistently reduced ejection fraction (pHFrEF).

Methods and results

A total of 7948 patients enrolled in the Metabolic Exercise Cardiac Kidney Indexes (MECKI) score database were evaluated (median follow‐up of 1490 days). We analysed clinical, laboratory, electrocardiographic, echocardiographic, exercise, and survival data from HFimpEF (n = 1504) and pHFrEF (n = 6017) patients. The primary endpoint of the study was the composite of cardiovascular death, left ventricular assist device implantation, and urgent heart transplantation. HFimpEF patients had lower HF severity: left ventricular ejection fraction 44.0 [41.0–47.0] versus 29.7 [24.1–34.5]%, B‐type natriuretic peptide 122 [65–296] versus 373 [152–888] pg/ml, haemoglobin 13.5 [12.2–14.6] versus 13.7 [12.5–14.7] g/dl, renal function by the Modification of Diet in Renal Disease equation 72.0 [56.7–89.3] versus 70.4 [54.5–85.3] ml/min, peak oxygen uptake 62.2 [50.7–74.1] versus 52.6 [41.8–64.3]% predicted, minute ventilation‐to‐carbon dioxide output slope 30.0 [26.9–34.4] versus 32.1 [28.0–38.0] in HFimpEF and pHFrEF, respectively (p < 0.001 for all). Cardiovascular mortality rates were 26.6 and 46.9 per 1000 person‐years for HFimpEF and pHFrEF, respectively (p < 0.001). Kaplan–Meier analysis showed that HFimpEF had better a long‐term prognosis compared with pHFrEF patients. After adjustment for variables differentiating HFimpEF from pHFrEF, except echocardiographic parameters, the Kaplan–Meier curves showed the same prognosis.

Conclusions

Heart failure with improved ejection fraction represents a peculiar group of HF patients whose clinical, laboratory, electrocardiographic, echocardiographic, and exercise characteristics parallel the recovery of systolic function. Nonetheless, these patients remain at risk for adverse outcome.