OBJECTIVE: The primary aim was to explore patients' knowledge of heart failure and their attitudes toward medical information (prognostic information in particular) and to assess different patient-related factors that might hamper the improvement of patients' knowledge. Moreover, taking the data obtained into account, we analyzed ethical aspects of information disclosure to patients with heart failure. SETTING: The study was performed at Sahlgren's University Hospital in Gothenburg, Sweden. DESIGN: The study was a qualitative analysis of semistructured interviews. PATIENTS: The sample included 40 patients with various stages of chronic heart failure. RESULTS: Many patients had only a limited understanding of their disease, but they still claimed that they were satisfied with the information they received. Some of them seemed to accept, to be indifferent to, or to be unaware of their low level of knowledge. The majority did not request prognostic information. CONCLUSION: We argue that patients with heart failure are adequately informed when they have reached the level of knowledge that enables them to be managed as effectively and securely as possible while being satisfied with the information provided. To give adequate information, health care providers should determine the patients' level of knowledge and explore why those patients who have a limited understanding do not assimilate or request information.