Heart valve surgery. Special tools being used to carry out keyhole heart surgery to replace a defective heart valve. The hole in the patient's chest (between two ribs) is held open by soft- tissue retractors to allow access to the heart. A set of metal retractors, not normally used in keyhole surgery, are also being used because this patient has an unusually deep chest. A hand- operated clamp (centre left) stabilizes the area being operated upon. Fibre-optic camera equipment (lower left) enters through another hole for an internal view. Keyhole heart surgery is less traumatic than open heart surgery (where the rib cage is opened).