THE CLINICAL-SIGNIFICANCE OF PERFORMING PREOPERATIVE ANGIOGRAPHY OF THE INTERNAL THORACIC ARTERY IN CORONARY-ARTERY BYPASS-SURGERY

This study was designed to clarify the clinical significance of and in dications for performing preoperative internal thoracic artery (ITA) a ngiography in patients undergoing coronary artery bypass surgery. A to tal of 300 possible candidates for coronary artyery bypass grafting (C ABG) underwent ITA angiography during diagnostic catheterization. Semi -selective angiography of bilateral ITAs were performed by injecting c ontrast medium manually with a 5-F right Judkins coronary catheter The posteroanterior view of the arteriograms was recorded on a 35-mm cine film or a cut-film. Unusual angiographic findings of the ITAs were ob served in nine patients (3%). These findings included: an atrophic ITA in three patients with ipsilateral subclavian artery occlusions; enla rged ITAs giving collaterals to the lower extremities in one patient w ith extensive aortoiliac occlusive disease; occluded ITAs in one patie nt with Takayasu's arteritis and two patients with a history of CABG; and a small but nonsclerotic ITA in one patient, Atherosclerotic occlu sive ITAs mere found in only one patient. Thus, we concluded that rout ine preoperative angiography of the ITA is not necessary because it is rarely affected by atherosclerosis. However, it should be performed f or any of the following reasons: a cervical or supraclavicular bruit; an upper extremity blood pressure difference of greater than 20 mmHg; an extensive aortoiliac occlusion; and certain disorders such as Takay asu's arteritis or Kawasaki disease, or a history of open heart surger y.