Constrictive pericarditis is a rare complication of cardiac surgery. Among 7851 patients who underwent cardiac surgery at Nantes University Hospital, postoperative constrictive pericarditis was diagnosed in 5 patients: 0.63%. All patients were men aged 49 to 77 years (mean 62.5) Four patients underwent coronary artery bypass graft surgery and one patient required mitral and aortic valve replacement. The mean time to onset of symptoms after the first operation was 21 months. The main clinical symptom was right ventricular failure. In all patients, the diagnosis was established by right catheterization which showed diastolic dip-plateau. A radical pericardectomy was performed in all but one of the patients, who was treated medically. Clinical signs resolved in all five patients. The diagnosis of constriction after cardiac-surgery is not easy, as the symptoms are non-specific. A symptomatic patient believed to have myocardial failure after cardiac-surgery could therefore actually instead have occult constriction.