Study group intervention: 7 sessions of transtheoretical model-based interview (2 in the first month, a total of 7 times, once a month), a structured disease education through transtheoretical model-based telehealth practices, and 6-month follow-up.

• After the participants are included in the study, a health education structured according to the Transtheoretical model will be given to the patients in the study group through tele-health applications.
• The patients in the intervention group will be trained through tele-health practices for at least 25-30 minutes on a transtheoretical basis, every 2 weeks in the first month and once a month in the following months. Tele-health applications include phone monitoring, SMS notification and application applications.
• In the 6-month follow-up, there will be 2 follow-ups as pre-test (1st month) and post-test (6th month).
• Behavioral: 7 sessions of behavior change training based on the transtoerytic model

• No notification will be made to the relatives of the patients in the control group. Control group patients will be called for routine control in line with their usual plans. After a total of 6 months from the beginning, the self-care and treatment compliance levels of the patients in the control group will be examined.
• There will be 2 follow-ups as pre-test (1st month) and post-test (6th month).

The Transtheoretical Model is a conscious behavior modification model that focuses on individual decision making and planning processes. It is the only model that examines behavior change as a dynamic process rather than an outcome, and considers behavioral strategies that include the individual's cognitive and behavioral processes in this process.

In the model, it is stated that behavior change is a process and develops gradually. It is reported that the change in the behavior of individuals consists of six stages: 1) not thinking, 2) thinking, 3) preparation, 4) taking action, 5) maintaining and 6) terminating. This model consists of four main constructs called change stages (time-related dimension), change processes/behavior modification methods (independent variable dimension), self-efficacy (levels of change) and decision-making balance (perceptions of harm and benefit of change).

The scale includes recognizing symptoms such as edema and weight gain, dyspnea, and fatigue associated with heart failure; It consists of 12 questions to measure self-care behaviors such as applying to a doctor and nurse for these symptoms, regular use of drugs, use of fluid and salt, treatment such as diet and exercise regimen and self-care behaviors such as weight monitoring and edema monitoring.

The total test score is obtained by summing the scores obtained from the scale items evaluating drug compliance. Scores from the scale range from 5 to 25. An increase in the obtained scores indicates compatibility, and a decrease in scores indicates inconsistency.