The aim of this study was to evaluate long-term changes in left ventricular (LV) mechanics after pericardiectomy in patients with constrictive pericarditis (CP) and to correlate post-operative LV mechanics with clinical status. A total of 24 patients with CP underwent serial speckle tracking echocardiography 1 wk before and 1, 6 and 12 mo after pericardiectomy. Global LV longitudinal, circumferential and radial strains, along with LV twist, were measured. Twenty-three healthy volunteers were served as control patients. Although global LV longitudinal, circumferential and radial strains obtained 6 mo after pericardiectomy increased compared with those for prepericardiectomy, they were still significantly lower than those for control patients. Further improvements occurred over time with normalization of global LV longitudinal and radial strains 12 mo after pericardiectomy, but global circumferential strain obtained 12 mo after pericardiectomy was still lower than that for control patients. LV twist remained unchanged after pericardiectomy. In addition, the improvements in global LV circumferential strain after pericardiectomy were associated with improvements in clinical symptoms (p < 0.001). These findings suggest that the global LV circumferential strain may be a promising parameter in the evaluation of the effectiveness of pericardiectomy. (C) 2016 World Federation for Ultrasound in Medicine & Biology.