In the middle of this century, coronary heart disease (CHD) is the most common cause of death in the United States. Chinese health service survey showed that about 1000,0000 ~ 320,000 people were suffering from CHD in the mainland of China in 2008. The high mortality and morbidity of CHD will aggravate the psychological burden of patients, such as depression. Depression is the most psychological problem in CHD patients. The incidence of depression in Chinese population was in the range of 4%~6%, while it was as high as 14%~17% in patients with CHD. Depression not only affects the patients' illness, but also reducing their quality of life, the compliance of drugs and lifestyle. In addition, depression is a major risk factor for the mortality and morbidity of cardiovascular disease. Therefore, it's urgently needed to screen and treat the depression of patients with CHD.

At present, the treatment of depression in patients with CHD mainly includes antidepressant, cognitive behavioral therapy， psychological counseling, knowledge education, relaxation therapy and so on. However, the medicine would yield side - effect. Furthermore, the content of psychological interventions are not systematic and dynamic. Moreover, patients' depressive level varies in different periods, the traditional psychological intervention just focused on the ultimate psychological benefits, and cannot analyze some factors and staged results in the process of psycho-behavioral change. Thus, an dynamic and effective intervention to alleviate depression in patients with CHD is imperative.

The transtheoretical model (TTM) is a purposeful behavioral change model. It is a systematic study of people's behavior change based on a variety of theories. Effective outcomes with TTM also have been applied in many studies of health behavior change, especially in the field of two aspects: on the one hand, to change unhealthy behaviors such as smoking, drinking, weight control and so on. Besides, a way to involve individuals in health behavior change is motivational interviewing (MI). MI is a way that taking patients as the center approach to interpersonal communication, which helps patients discover and overcome their ambivalence, thereby triggering behavioral changes. A study showed that MI might have favorable effects on changing patients' depression and found that the effect of a single use of MI was better than that of cognitive-behavioral therapy. In summary, the TTM-based interventions and MI were used to change behavior fields. To our knowledge, few studies have been conducted to determine the effects of the TTM-based intervention and MI on depression. Therefore, this study decided to determine the effects of TTM-based intervention and MI on the management of depression in hospitalized patients with CHD.

The aim of this study was to determine the effects of TTM-based intervention and MI on patients' stages of change, processes of change, decisional balance, self-efficacy, and depression. The study's hypothesis was: (1) The patients in the intervention group would be a positive shift in stages of change, the scores of cognitive level, behavioral level, perceived benefits, self-efficacy, perceived barriers and depression after intervention compared with the control group.

The sample comprised 110 (each group: 55) patients with coronary heart disease (CHD) in the Medicine-Cardiovascular Departments of three hospitals in Changsha.

The whole trail was on the basis of the CONSORT statements and a single, blind, randomized, controlled trial. Study procedures were approved by the institutional review boards of all participating All patients were recruited by enrolling researchers for eligibility and then enrolled in the study if they were eligible and informed consent. Patients were randomly divided into two groups by using a block randomization list with a block size of 4 at 1:1.

A research assistant put the generated random number into opaque consecutively numbered envelopes and sealed the envelopes, and then handed it to enrolling researchers. When the eligible patients were recruited in the study, the enrolling researchers numbered the patients, opening the same numbers sealed envelopes. The enrolling researchers were blind about the design of this study.

The patients in the intervention group received conventional care, TTM-based intervention and MI; Interventions were provided by trained nurses. First, The leader of this research contacted the hospital, getting the consent of the relevant departments and ward heads of the hospital to screen research objects before the beginning of the study, telling patients the purpose, significance, methods of the research, times to fill out the questionnaire, and the possible risks and benefits of the study.

The MI was implemented 2 times, 20 minutes each time, the trained nurses interviewed each patient face-to-face in the unit. Data were collected at 2 time points: the patient was on admission (T, obtain the baseline information) and the patient was 2- days before discharged (T0, obtain the information after intervention), according to the assessment of their current stage of change and depression delivered by filling the Stages of Change Subscale and Hamilton Rating Scale. TTM - based intervention was given 3 times in the form of a small course, 20 minutes each time according to the changing stage.

No interventions were performed for the control group participants during the study. However, these patients received conventional care ( nursing procedure, education about diet, exercise and so on).

Data were collected by a research assistant who was blind to the study design and allocation of participants. At baseline, sociodemographic and clinical characteristics were collected from medical records and personal interviews.

Criteria: Inclusion Criteria:

• Be diagnosed as coronary heart disease (typical clinical angina manifestations, electrocardiogram changes, and coronary angiography) confirmed by the World Health Organization / International Cardiology in October 1997 and cardiac function is graded from I to III;
• Must be volunteered to participate in the study;
• Must be conscious with clear communication ability.

Exclusion Criteria:

• Had cerebrovascular accident, malignant tumor, malignant hypertension(systolic pressure >180 and/or diastolic pressure >100 mmHg);
• Had a psychiatric history or serious cognitive conscious obstacles;
• Had been participated in other similar research subjects;
• No mobile phone or home phone is available for contacts.

The process of data collection cost a lot of human and material resources,some of the data was privacy information of participants, and so on.Considering this, it is improper to share these data.

The leader of this study entered the cardiovascular medical ward and screened potential eligible patients according to medical records in each hospital. Leaders informed the purpose, significance, methods, sessions of the study to patients. Patients were randomly divided into two groups by using a block randomization list with a block size of 4 at 1:1. A research assistant put the generated random number into opaque consecutively numbered envelopes and sealed the envelopes, and then handed it to enrolling researchers. When enrolling a new participant, the enrolling investigators opened the sealed envelope after participant's name was written on next available envelopes. A sequentially numbered and opaque, sealed envelope system was used by a non-investigator. Additionally, all data collection was conducted by another research assistant who was blind to the study design and allocation of participants.