The National Registry of Supported Angioplasty was formed in 1988 to collect data on patients undergoing supported angioplasty. The Registry was expanded to include patients also undergoing standby supported angioplasty. In 3 years the Registry collected data on 801 patients undergoing supported or standby supported angioplasty. The data indicate that in patients with low ejection fractions and/or > 50% of jeopardized myocardium at risk can have an interventional procedure performed with a 6.9% risk of mortality with prophylactic or standby support, but patients with < 20% ejection fraction do better with prophylactic support. In addition, patients with LMCA stenosis and age > 70 years are at higher risk. The Registry also demonstrates good long-term results for patients who have undergone the procedure.