Applications of digital subtraction angiography in cardiovascular diagnosis.

Both intravenous and intra-arterial DSA have widespread applications in the field of cardiovascular diagnosis. The definition of carotid artery stenosis or severe peripheral vascular disease in the patient undergoing coronary artery bypass surgery might dictate the need for simultaneous carotid and coronary artery surgery or demonstrate the best route for insertion of an intra-aortic balloon. DSA also might find further application in the definition of thoracic aortic dissection, thoracic aortic trauma, and coarctation of the thoracic aorta, as well as in showing the adequacy of repair of thoracic coarctation in patients who remain hypertensive postoperatively. Left ventricular imaging using intravenous or intraventricular injections of contrast material provides an accurate method of calculating ejection fraction and an excellent picture of left ventricular wall motion. In addition, because smaller amounts of contrast material may be used for intraventricular infections, patients with renal failure or severe impairment of the left ventricle might fare better with the reduced contrast load. Multiple ventriculograms can be performed following interventions such as pacing or exercise to allow a more adequate definition of left ventricular performance. Intravenous DSA still has not achieved satisfactory visualization of the coronary arteries or coronary artery bypass grafts. However, aortic root injections of contrast material can provide adequate definition of these structures and has been recommended as a screening technique for coronary disease in patients undergoing arteriography for other vascular disease. Current work on the development of DSA techniques for the quantitation of coronary artery blood flow and myocardial perfusion is quite promising. Accurate, reproducible measurement of coronary artery blood flow, patterns of myocardial perfusion, and areas of myocardium supplied by specific coronary vessels with obstructions may soon provide physiologic information about anatomically defined coronary artery disease. A variety of congenital heart defects have been defined by intravenous DSA. Shunt lesions such as atrial septal defects, ventricular septal defects, and patent ductus arteriosus have been defined anatomically, and the severity of their shunts has been estimated by placing windows of interest over the various cardiac chambers. It is possible that certain congenital malformations might be studied adequately by intravenous DSA, eliminating the need for cardiac catheterization.(ABSTRACT TRUNCATED AT 400 WORDS)