The waffle procedure is performed in patients with marked thickening and calcification of the epicardium and no substantial improvement in hemodynamic parameters after pericardiectomy. We retrospectively investigated the efficacy of the waffle procedure in 6 of 11 patients who underwent pericardiectomy. These 6 patients showed no improvement in central venous pressure, pulmonary arterial pressure, pulmonary capillary wedge pressure, or cardiac index after pericardiectomy. After the waffle procedure, all hemodynamic parameters improved, and there were no significant differences compared to those of the 5 patients who did not require the waffle procedure, despite higher pulmonary capillary wedge pressure and lower cardiac index values preoperatively in the waffle group. The waffle procedure was considered effective in patients with persistent epicardial constriction.