Feasibility and Complications of the St. Jude Medical Mechanical Heart Valve- A Brief Study

Abstract

Background: The St. Jude Medical bileaflet mechanical valve was designed by Xinion (Chris) Posis and Donald Hanson who came up with the concept of a leaflet-tab rotating in a "butterfly recess" in the inner wall of the housing with the hinge mechanism located near the central axis of the housing. The bileaflet configuration provided central, evenly distributed flow patterns with small areas of flow separation, minimal flow resistance, low profile, large effective orifice area, and ease of surgical implantation. The valve leaflets and housing were made of pyrolitic carbon and the sewing cuff of double velour dacron. The valve satisfies many of the features of an ideal valve such as long-term durability, non thrombogenicity and hemodynamic efficiency. However, its clinical dependence on chronic anticoagulation persists. Methods: Between January 2003 to December 2014, 430 patients were studied who had undergone or underwent mitral valve, aortic valve or double valve (both aortic and mitral) replacement with the St. Jude Medical bileaflet valve. Results: A total of 430 cases were studied. The mean age of operation was 39.16± 9.7 years. The operative mortality rate was 5.5% overall. The average period of follow-up was 4.21± 3.2 years. Structural valve deterioration was not seen in any patient in the series. Nonstructural valve dysfunction was reported in 7 patients. Clinically significant hemolysis was not seen in any patient. Thromboembolism was reported in 22 patients. Valve thrombosis was reported in 3 patients. Major bleeding events requiring hospitalization or transfusion were reported in 17 patients. PVE was reported in 4 patients. There were 36 late deaths. 21 patients died of valve related causes, 9 from cardiac causes and 6 patients from non-cardiac causes. Overall survival rate was 90.66%. Conclusions: Even though the St. Jude Medical bileaflet mechanical valve satisfies most of the features of an excellent mechanical valve substitute, the late valve related complications (especially thromboembolism and bleeding) and mortality, although low, illustrate that our quest for a "perfect" prosthesis remains.