Resection of left atrial myxoma and large atrial septal defect repair were performed in 55 patients using the da Vinci S surgical system to evaluate device safety and efficacy. Fifty-five patients underwent resection of left atrial myxomas (n=10) or secundum-type ASD (n=45) repairs with three cases of concomitant tricuspid valve repairs, using the da Vinci S surgical system. Mean age of the patients was 38+/-12.2 years (range 12-61 years). Cardiopulmonary bypass was achieved peripherally, aortic occlusion was performed with Chitwood cross-clamp, and antegrade cardioplegia was administered via anterior chest. Via four port incisions in the right chest and a 2-2.5-cm working port, all the procedures were completed with the da Vinci robot. All patients had successful resection or repairs. The mean CPB times and aortic cross-clamp times were 108.6+/-12.5 min and 45+/-11.5 min, respectively. There were no operative deaths, strokes, or device-related complications. One patient was reexplored for bleeding. There were no incisional conversions. All the patients were discharged. da Vinci S surgical system has no limitations to safe resection of left atrial myxomas and of ASD repairs, surgical results are excellent, and this technology is of reproducible value with excellent cosmetic results.