This study is investigating whether a series of psychological exercises, called positive psychology, provides benefit to patients who have been hospitalized for heart disease (an 'acute coronary syndrome' or heart failure).

In this study, subjects are randomly assigned to complete 8 positive psychology exercises over 8 weeks, or to complete different exercises in control groups.

We hypothesize that patients who are assigned to the positive psychology tasks will be able to complete the exercises at a high rate, will feel that the exercises were easy to perform, and will have greater improvements of optimism, anxiety, mood, and health-related quality of life than subjects in the control conditions.

Inclusion Criteria:

• Hospitalization at Massachusetts General Hospital for an acute coronary syndrome or congestive heart failure
• Able to read/write in English
• Have working home or cellular phone

Exclusion Criteria:

• Cognitive disorder
• Medical condition likely to lead to death within 6 months
• Illness leading to inabilty to consent or complete study exercises
• Current or prior participation in positive psychology interventions