Figure 1. Study timeline illustrating experimental design. (A) At week 0, heart failure and Sham surgery were made. After 4 weeks, heart failure rats were evaluated by echocardiography to determine cardiac diameters. At 8-weeks, echocardiography, arterial doppler and procedures for assessing spatial and related forms of learning and memory were performed. (B) To determine spatial acquiring learning, rats were trained for two day, then tested for five consecutive days, followed by two days of rest, and three more days of testing. The 10th day, the platform was removed. (C) Followed spatial acquiring learning and after 2 days of rest, same set of rats performed memory flexibility test for four consecutive days and the position of the platform was changed daily.