Background To date, contemporary heart failure care remains patient-focused, but awareness of the partners' and families' situation is increasing. Randomized studies have mainly evaluated the short-term effects of dyadic interventions. Therefore, the aim of this study was to determine the 24-month effects of an intervention with psych-educational support in dyads of heart failure patients and their partners. Methods This study used a randomized study design and 155 patient-partner dyads were enrolled. The intervention included a nurse-led program of three sessions addressing psychoeducational support. Results The intervention did not have any effect on health, depressive symptoms or perceived control among the patient-partner dyads after 24 months. Furthermore, time to first event did not differ significantly between the intervention group and the control patients. Conclusion This study may be regarded as a first step in trying to understand dyads' need for supportive care. Individualized and more targeted interventions seem necessary to achieve a higher impact on dyad outcomes.