Syunei Kyo

Improved Survival in Patients with Continuous-Flow Ventricular Assist Device for Bridge to Heart Transplantation

BACKGROUND Contemporary continuous-flow ventricular assist devices (CFVADs) have greatly improved patient survival for indications of bridge to transplantation (BTT) and destination therapy. In Japan, CFVAD is limited for BTT use. The waiting period for heart transplantation (HT) is long owing to donor shortage. We examined the results of CFVAD for BTT indication. METHODS Eighty-nine VAD treatments were performed among subjects whose preimplantation condition was profile 1 (n = 49) or profile 2 or 3 (n = 40). The device was the paracorporeal pulsatile Nipro VAD (n = 67) or CFVAD (n = 22). All CFVAD patients were profile 2 or 3. RESULTS The median assist period was 529 days (Nipro VAD, 530; CFVAD, 528). Twenty-six patients were on the device for >2 years. Actuarial survival was 81.6%, 69.5%, and 61.1% at 1, 3, and 5 years. Survival in profile 1 was significantly worse than in profile 2 or 3. Survival of CFVAD patients was superior to that of paracorporeal VAD. Six-month mortality rate of 20% in cases before 2009 (n = 60) was dramatically improved to 3% among those after 2010 (n = 29). All patients with CFVAD were alive and discharged home. 26 patients were transplanted, 7 had been weaned from VAD and 27 were on a device. The rate of events requiring hospital admission was 0.98 per patient-year in CFVAD patients. CONCLUSIONS Contemporary CFVADs have enabled advanced heart failure patients to await HT safely with an improved quality of life. The advent of CFVAD has also shifted their preimplantation condition to a less sick status. CFVADs were the safest, most reliable circulatory support devices for long-term waiting periods for the BTT indications.

Safe and minially invasive palpaiton device for detection of lung tumor during thoracoscopic Surgery

Though palpation is useful method to detect pulmonary nodules with open thoracotomy, it is very difficult in case of thoracoscopic surgery. We have developed a palpation device to this end. A pressure sensitive conductive rubber is used to measure hardness of tissue. The diameter of sensor units is small enough to pass thorough a trocar. The pressure-output property of the sensor unit was evaluated at laboratory. We could detect the tumor model in lung from in vivo experiments. Safety mechanism that limits the pressure applied by the palpation device was proposed. We are plan to apply the palpation device to endoscopic based navigation system.

Direct minimally invasive intraoperative electrophysiological mapping of the heart

Abstract Introduction: Cardiac electrophysiology aims to describe and treat the electrical activity of the heart. Although an epicardial approach is valuable in many surgical treatments such as coronary artery bypass grafting, maze ablation, and cell transplantation, very few techniques suited for minimally invasive surgery are available for measurement of epicardial electrophysiology. Material and methods: We developed a novel endoscopically-deployable expanding electrode array that can be applied for minimally invasive surgery. Our device consists of a flexible electrode array attached to arms which open and close the electrode sheet. Furthermore, we also developed a computer program to overlay an epicardial electrophysiological map on an endoscopic image. We performed both laboratory and in vivo experiments to examine the feasibility in clinical situations. Results: Evaluation experiments demonstrated that our novel mapping process that assumes spherical deformation of the electrode array enables us to overlay each electrode position with an accuracy of < 1 mm. Results of animal experiments using large animals (one dog and two pigs) demonstrated that our system enables construction of epicardial electrophysiological maps. Conclusion: A novel endoscopically deployable expanding electrode array was developed. Evaluation experiments demonstrated that our device can be manipulated in simulated minimally invasive surgery, and enables construction of epicardial electrophysiological maps.