Enhanced external counterpulsation (EECP) was used to treat 30 patients with refractory angina due to cardiac Syndrome X, with an initial improvement in CCS angina class (3.57 to 1.43; p<0.001) and regional ischemia in all treated patients. At a mean of 11.9 months follow-up, 87% of patients had sustained improvement in angina and were without MACE. EECP, by improving endothelial function, may be an effective and durable treatment for this often difficult to treat problem.