Coronary artery perforation secondary to percutaneous coronary intervention (PCI) is a rare, but a potentially life-threatening complication. There is a misconception that cardiac tamponade rarely occurs in patients with prior coronary artery bypass grafting (CABG). We first describe a giant right ventricular intramural hematoma following PCI via a saphenous vein graft to treat a distal stenosis of the right coronary artery, and its successful treatment with redo cardiac surgery. Complex elective PCIs on patients after CABG should be performed in specialized centers with a well-established heart team that has the expertise to treat any of the potential complications.