Abstract Background There are diversities of pathophysiology and co-morbidities in patients with chronic heart failure (HF), irrespective of left ventricular ejection fraction (LVEF). Therefore, the identification of subgroups with different outcomes and treatment response patterns may help to tailor strategies to each individual HF patient. Purpose We sought to identify phenogroups of patients with different prognosis and response to medical therapies in patients with chronic HF. Methods A total of 1565 patients with a broad spectrum of LVEF in a prospective multicentre registry of patients with chronic HF were enrolled between January 2020 and December 2023. Latent class analysis was performed in each subgroup using 80 features including patients’ demographics, laboratory, and echocardiographic data. The optimal number of phenogroups was determined using the first minimum of the Bayesian information criterion. The primary outcome was a composite of all-cause death and hospitalisation due to worsening HF. Results The analysis subclassified patients into six phenogroups. Patients in phenogroup A (young non-ischaemic cardiomyopathy, n = 242, 15.5%) were the youngest and had lower LVEF and lowest prevalence of coronary artery disease (CAD) and other comorbidities. Phenogroup B (atrial fibrillation [AF] and small left atrium, n = 282, 18.0%) had higher proportion of AF but smaller left atrium volume. Phenogroup C (ischaemic cardiomyopathy, n = 204, 13.0%) had the highest proportion of CAD and lower LVEF. Phenogroup D (classical HF with preserved ejection fraction [HFpEF], n =308, 19.7%) had the highest age, proportion of female, LVEF and thickness of LV wall. Phenogroup E (elderly and AF , n = 235, 15.0%) had higher age, the highest proportion of AF and largest left atrium volume. Phenogroup F (biventricular failure and multiple comorbidities, n = 294, 18.8%) had the highest proportion of co-morbidities and the lowest LVEF, right ventricular systolic function and renal function. During a median follow-up period of 538 (interquartile range 286-701) days, the incidence of the primary outcome significantly differed among the phenogroups (P < 0.001, Figure 1). Regarding treatment response for renin-angiotensin system blockers and beta blockers, there were no significant associations between the use of renin-angiotensin system blockers and the risk of the primary outcome among the phenogroups whereas the use of beta-blockers was significantly associated with increased risk of the primary outcome in patients classified to phenogroup D (classical HFpEF) (hazard ratio 1.83 95% confidence interval 1.05-3.19) among the phenogroups (Figure 2). Conclusion We identified six phenogroups with distinct clinical outcomes in patients with chronic HF, and the use of beta-blockers might have unfavorable effect in the classical HFpEF phenogroup. This phenotyping provides novel risk stratification and may aid in clinical decision making.Clinical outcomes among the phenogroupsTreatment effect among the phenogroups