Background: Constrictive pericarditis is a debilitating disease and reversible constriction is a well-described phenomenon. However, factors which predict reversibility remain unknown. No study has shown factors that might predict reversibility and thus preclude these patients from pericardiectomy which has its own host of debilitating sequelae. In this study we sought to look into factors which predict constriction reversibility in CP patients. Method: We evaluated 48 consecutive patients who developed CP following the first attack of pericarditis in year 2011. All patients were treated with NSAIDs, colchicine and steroids as first treatment. Demographics, etiology, laboratory, echocardiograpic and outcome data were collected retrospectively using electronic medical record offline echocardiograms films. Results: 27 patients had reversibly constriction with medical therapy only and 19 patients underwent pericardiectomy who were identified as irreversible. Those who had surgery had normal inflammatory marker (ERS, 11.8±7 vs. 40±25, CRP 2.5±2 vs. 6.9±3.1, p=0.001), more septal bounce (17 vs. 7, p=0.001), and more dilated inferior vena cava (2.69±0.4 vs. 2.12±0.35, p=0.001) and less inspiratory collapse (3 vs. 20, p=0.001). Furthermore, patient who had surgery had thicker pericardium on echo confirmed with cardiac MRI (0.74 vs. 0.45 vs. 0.41±0.5, p=0.28). Using tissue doppler, septal and lateral E/e' were higher among those who had reversible disease (11.36±4.8 vs. 7.25±1.9 p=0.001 and 9.8±3.9 vs. 5.9±2.4, p=0.001), respectively. On multivariate analysis, septal bounce correlated with need for surgery (p<0.05). High ESR and high E/e' lateral correlated with resolution (p<0.05). Conclusion: In CP, pericardiectomy can be the ultimate treatment in advanced cases. In few cases CP can be reversible and respond to medical therapy only. In this study we identified septal bounce, increased pericardial thickness, and normal inflammatory markers as predictors for pericardiectomy, which represent less inflammation and more fibrosis as pathology of pericardial constriction. On the other hand, higher inflammatory markers, and mitral valve annular velocity, as predictors for reversibility and potential to response to medical therapy. Knowing features that describe reversible disease will be helpful in pursuing aggressive medical management for those who will benefit and avoiding unnecessary surgery.