The acorn cardiac support device (ACSD) is a device designed to treat heart failure by containing the heart to prevent further dilation. Six patients with symptomatic heart failure due to ischemic cardiomyopathy were treated surgically with ACSD. All patients simultaneously underwent coronary artery bypass grafting. Ventricular reconstruction was also performed in 5 of the 6 patients. We followed up the patients for 12 months postoperatively, monitoring the left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD), mitral regurgitation, and NYHA classification. Both the LVEDD and LVESD were significantly improved one month postoperatively (from 63.2 to 50.6 mm, p=0.004, and from 51.6 to 39.5 mm, p=0.025, respectively). These dimensions did not change significantly over the next 11 months. NYHA functional class improved significantly from a mean of 3 to 1.4 at 12 months (p=0.012). Mitral regurgitation improved from a mean of 2.7 preoperatively to 1.4 at 12 months and the average LVEF also improved from 27% preoperatively to 35.9% at 12 months after surgery. However these latter two results were not statistically significant. There were no late deaths and no readmissions for heart failure. Repeat coronary angiography at 6 months revealed patent grafts in all patients. The mid-term results of ACSD for patients with symptomatic heart failure suggest that ventricular containment may be useful for preventing further cardiac dilation in patients with ischemic cardiomyopathy. Randomized, long-term studies are needed to assess the efficacy and possible role of ASCD in the future management of heart failure.