This report describes transoesophageal echocardiographic (TEE) monitoring in a one-year-old boy undergoing patent ductus arteriosus (PDA) interruption. After application of a first vascular clip, echocardiographic monitoring detected incomplete interruption of ductal flow, prompting the surgeon to add a second clip to the ductus. The procedure was performed via a new surgical technique: video-assisted thoracoscopic surgery (VATS). This innovative approach offers many advantages to patient care including reduced postoperative pain and better preservation of pulmonary function. We conclude that the use of TEE monitoring during PDA interruption via the VATS procedure may improve the surgical result, and eliminate reintervention and the complications associated with residual ductal flow.