Postsystolic shortening as indicator of regional myocardial dysfunction in patients with bipolar disorder

BACKGROUND Patients with bipolar disorder (BD) have a high risk of heart failure. Postsystolic shortening has been proposed as a novel indicator of early cardiac dysfunction. In this exploratory study, postsystolic shortening and its potential association with BD characteristics, cardiometabolic risk factors, and inflammatory markers were evaluated in young adults with BD and mentally healthy individuals. METHODS This study included 77 and 72 individuals in BD and mentally healthy control groups aged ≤45 years, respectively. The participants underwent two-dimensional speckle-tracking echocardiography, with postsystolic shortening index values calculated from the strain curve by using the following equation: ((maximum strain in cardiac cycle - peak systolic strain)/maximum strain in cardiac cycle) × 100. Cardiometabolic risk factors and inflammatory markers were derived from standard examinations in the hospital. RESULTS Postsystolic shortening index values for the myocardial regions supplied by the left anterior descending artery (LAD; Cohen's d = 0.22, p = 0.057), left circumflex artery (LCX; Cohen's d = 0.34, p = 0.017), and right coronary artery (Cohen's d = 0.30, p = 0.003) were greater in patients with BD than in mentally healthy individuals of a similar age. Correlation analysis revealed that cardiometabolic risk factors and inflammatory markers in the BD group were positively correlated with higher postsystolic shortening index values for the LAD and LCX regions. CONCLUSION Postsystolic shortening is a potential indicator of regional myocardial dysfunction in patients with BD. Future replication studies should verify the current findings and investigate the mechanisms underlying the observed associations in this study.