Providing the fetus with calcium.

internal mammary grafts, and prosthetic tube grafts. The results with all these are either dismal or unknown. One other option is the use of the free internal mammary artery. This method extends the range of the grafts and gives results with an enhanced long term patency similar to those with pedicled internal mammary artery grafts,'3 but it imposes a technically awkward requirement for a proximal aortic anastomosis and still may not provide enough conduit for all of the vessels requiring grafting. Surgeons are looking for further possible second arterial conduits, and current interest has centred on the right gastroepiploic artery being left as a pedicled graft fed from the gastroduodenal artery.17-l9 It should be possible to use double internal mammary artery grafts to the left anterior descending and circumflex systems supplemented by the right gastroepiploic artery to the inferior surface and so to achieve total arterial revascularisation.20 What about those grafts that have failed? Balloon angio-plasty or revisional surgery are possible options. Balloon angioplasty may be effective in opening up stenoses in internal mammary artery and saphenous vein grafts, although any instrumentation in old saphenous vein grafts carries a risk of distal emboli from atheromatous or thrombotic debris. The long term outcome after graft dilatation is unknown, but in internal mammary artery and saphenous vein grafts in two consecutive series of patients ten years after operation. 5 Bulkley BH, Hutchins GM. Accelerated "atherosclerosis." A morphologic study of 97 saphenous vein coronary artery bypass grafts. A platelet inhibitor drug trial in coronary artery bypass operations: benefit of perioperative dipyridatmole and aspirin therapy on early vein graft patency. Improved aortocoronary bypass patency by low-dose aspirin 100 mg daily): effects on platelet aggregation and thromboxane formation. Lancet 1984;i: 1261-4. reoperation is associated with 90% survival at five years and 75% at 10 years.2' In the early 1980s the concept of "complete revascularisa-tion" was popular; it was based on the belief that grafts should be made to all vessels with stenoses tighter than 50%. We are now more realistic, taking account of the uncertain progression of underlying coronary artery disease. Given the likelihood that (for the near future, at least) saphenous vein grafts will continue in common usage, coronary surgery should be seen as a palliative rather than a curative procedure. While increased use of the internal mammary artery is indicated, particularly to the left anterior descending coronary artery, restriction of grafting to coronary …