Background:
Progress in drug development and the stringent implementation of guideline-recommended pharmacotherapy contributed markedly to the improvement in prognosis of patients with heart failure and a reduced ejection fraction. However, most randomised trials included patients with symptomatic heart failure, although a sizeable proportion of patients becomes asymptomatic (NYHA I) with temporary treatment. The identification of disease mechanisms and biomarkers that predict outcome in well-defined cohorts may help in identifying new therapeutic targets.
Methods:
We designed the observational prospective “Transition from asymptomatic to symptomatic systolic chronic heart failure study (TRANSITION-CHF)”, funded by the German Cardiovascular Research Center (DZHK). We included patients with asymptomatic heart failure (NYHA I) with a current left ventricular ejection fraction (EF) ≤ 40% who had experienced maximum one episode of hospitalization for decompensated heart failure more than 2 years prior to the baseline visit. Patients were comprehensively phenotyped focusing on blood-based biomarkers, comorbidities, gender aspects, nutrition, and functional parameters including quality of life (QoL). All patients are followed annually for 5 years.
Results:
Between December 2014 and October 2023, 997patients were enrolled and analysed at 19 study centers in Germany. Their mean age was 60.1±13.7 years and 18 % were women. Further details are shown in table 1.

Conclusion:
These first results from Transition-CHF exemplify that asymptomatic patients with HFrEF have similar baseline characteristics compared to HFrEF participants studied in randomised HF trials, but show substantial differences with regard to presence of symptoms and physical performance. The ongoing follow-up will provide a better understanding of the natural course of this understudied patient population.