Yarali Duosti - Faculty of Clinical Psychology, Sari Branch, Islamic Azad University, Sari, Iran.
Marzieh Mohammadi Pashaki - Faculty of Clinical Psychology, Sari Branch, Islamic Azad University, Sari, Iran.
Bahram Mirzaian - Faculty of Clinical Psychology, Sari Branch, Islamic Azad University, Sari, Iran.

Background: The cardiac function of patients with acute myocardial infarction plays a vital role in disease prognosis. The risk of ischemic heart disease and death in people with type D personality is 4 times more than those with lower levels of negative affect and social inhibition. In this regard, lifestyle is the objective and quantifiable dimension of human personality. Objectives: The research aimed to model the cardiac function based on type D personality with the mediating role of health-promoting lifestyle in patients with acute myocardial infarction. Materials and Methods: The present research has employed a correlational method based on structural equation modeling, especially the regression equation. The statistical population of this research included all patients with acute myocardial infarction (ST-segment elevation MI) under primary percutaneous coronary intervention referred to Mazandaran Cardiac Center in Sari City, Iran, from 2017 to 2018. A total of 220 patie nts were selected through the Muller regression equation modeling formula, considering the ratio of the sample size to the free parameter, by the purposive sampling method. They responded to the D personality questionnaire and the health-promoting lifestyle questionnaire. Results: Type D personality variable can directly predict the cardiac function of patients with acute myocardial infarction. This variable also predicts the cardiac function of these patients through the mediation of a health-promoting lifestyle. Conclusion: Type D personality has a direct and indirect effect on the heart disease and prognosis of patients with myocardial infarction (because of the mediating role of health-promoting lifestyle), and screening for this personality type is necessary.

Type D personality, Lifestyle, Cardiac function, Acute myocardial infarction