Methods
We retrospectively reviewed 130 adult patients (age ≥ 18 years) who underwent pericardiectomy with a prior history of mediastinal irradiation, from June 2002 to June 2019 at the Mayo Clinic in Rochester, Minnesota. Both primary and re-operative procedures were included. The study was approved by the Institutional Review Board at Mayo Clinic, Rochester, Minnesota (Date 2/8/2019, IRB no - 19-000542). Individual patient consent requirement was waived as the study was deemed a minimal-risk retrospective study; 2 patients without research authorization were excluded. Patient characteristics were obtained from the prospectively collected database based on definitions set forth by the Society of Thoracic Surgeons (STS) Adult Cardiac Database with additional review of patient records for supplementing missing information.14
Patients who underwent pericardiectomy for an indication other than a pre-operative diagnosis of constriction (N=28) were excluded, leaving 100 patients for study inclusion. Our surgical approach and operative techniques for pericardiectomy have been previously reported.7, 10, 15-17 A radical resection was defined as removal of anterior, inferior (diaphragmatic) and lateral pericardium posterior to the phrenic nerves. Any pericardial resection that did not meet the criteria for radical resection was defined as subtotal resection. Operative mortality was defined as any death, regardless of cause, occurring within 30 days after surgery, or during the same hospitalization as the index surgery, regardless of time.