Nuclear magnetic resonance and cardiovascular surgery

Nuclear magnetic resonance appears to add an entirely new dimension to present-day diagnostic modalities. Because of its ability to distinguish stationary tissue from blood, clinically available noninvasive proton imaging may produce anatomic detail as accurate as angiography for the evaluation of myocardial function and anatomy. Although specific atherosclerotic lesions may not be discernible, the patency of native vessels, as well as saphenous vein bypass grafts, should be easily discernible and NMR may become the procedure of choice for evaluation of patients who have had myocardial revascularization or percutaneous coronary dilatation. Similarly, NMR lends itself perfectly to diagnosis of peripheral vascular lesions, again with the added safety of a noninvasive procedure. Certainly one of the most fascinating capabilities of NMR is its ability to evaluate muscle bioenergetics, that is, to assay tissue oxygen supply and demand noninvasively. Although magnets capable of imaging phosphocreatine or adenosine triphosphate content are expensive, experimental, and in the early stages of development, it is through just such efforts that medicine truly may be able to understand and advance its treatment of congenital and ischemic heart disease.