Patients who are going to use oral anticoagulant will participate in an individual orientation, using instructional material (slides and illustrative booklet) during hospitalization period. After the discharge 2 phone calls will be done (after: a week and four weeks) focusing on the strategies to improve patient's self-efficacy to manage the oral anticoagulation. There will be a personal contact among researcher and participants when the patients return at the oral anticoagulant ambulatory, two months after the treatment start. At this time the following variables of interest will be evaluated: Health-related quality of life; adherence to treatment and patients' self-efficacy.