Thrombectomy with Disc Rotation of Medtronic Valves

Abstract

Thrombotic obstruction of prosthetic valves is a serious problem. Early diagnosis and prompt treatment are life-saving in these cases. Three patients presented with subacute and chronic symptoms of prosthetic valve thrombosis of varying duration (7 days to 2 years). All 3 had a Medtronic Hall tilting disc valve implanted in a previous operation in the aortic or mitral position. Diagnosis was established by 2-dimensional echocardiography. Under cardiopulmonary or femorofemoral bypass, thrombectomy and rotation of the disc within the valve housing were performed through a median sternotomy. All the patients had an uncomplicated postoperative course. Pressure gradients fell markedly at discharge 8 to 10 days after surgery. The patients were followed up for between 3 and 11 months, during which they showed excellent prosthetic valve function and reduced gradients. The ability to rotate the valve within the housing allows adequate thrombectomy and pannus excision. Even several years after implantation (more than 10 years in 2 cases), the valve could still be rotated readily to obtain optimum flow and low pressure gradients.

Disc Impediment in Medtronic-Hall Aortic Valve Prosthesis Followed by Successful Reoperation

“…This valve position provided the optimum blood flow and improved the valve performance. Orienting the larger orifice toward the greater curvature of the ascending aorta creates a near-physiological, or laminar, flow pattern (13). This is possible only with tilting disc prostheses as they possess 2 orifices and, hence, experience less turbulence.…”

“…The same cannot be achieved with bileaflet valves because they possess 3 orifices. Consequently, the gradients across a Medtronic-Hall valve in the optimum position will be lower compared with bileaflet valves (e.g., a St. Jude Medical valve) of the same size in any orientation (13).…”