Early investigation of silver-coated Silzone (TM) heart valves prosthesis in 126 patients

Background and aim of the study: Permanent silver (Silzone (TM)) coating of the sewing cuff of St. Jude Medical prosthetic heart valves may reduce the rate of prosthetic valve endocarditis (PVE). However, the incidence of par avalvular leaks and stroke in patients after implantation of Silzone-coated heart valve prostheses is largely unknown. Methods: Complications were analyzed among 126 consecutive patients (78 mal es, 48 females; mean age 64.7 years; range: 40-80 years) who received Silzo ne-coated prostheses at our institution between February 1998 and December 1999. Among patients, 94 had aortic valve replacement, 29 mitral valve repl acement, and three had aortic and mitral valve replacement. Concomitant car diac procedures (mainly coronary bypass) were performed in 47 patients (37. 3%). Results: Hospital mortality was 1.6% (2/126) and freedom from valve-related mortality 99.2 +/- 0.9%. Total follow up was 137.4 patient-years, and 98.4 % complete. Strokes or transitory ischemic attacks (TIAs) occurred in four cases (two strokes, two TIAs; stroke rate 1.5%/year; 95% CI 0.4-2.6%/year; stroke+TIA rate 3%/year; 95% CI 0.4-5.25%/year). There was no case of prost hetic valve dysfunction or PVE. Freedom from reoperation due to procedure-a ssociated complications was 97.6% (one aortic dissection, two major bleeds) . Paravalvular leak was detected in 19 cases, and graded trivial or mild in 17 cases (11 grade 0-I, six grade I), and moderate in two cases (grade III in one, grade II in one). No patient needed reoperation due to paravalvula r leak. Left ventricular (IV) function was normal in 80 cases, but was impa ired mildly in 20 cases, moderately in 16, and severely in eight. Bicycle e xercise testing in 92 patients (73%) showed median exercise performance (81 .4 +/- 23.9% of normal) after correction for age and weight. Cerebral magne tic resonance imaging was performed in 64 patients (50.8%); median MRI scor e was 2.0 +/- 1.8 according to a 12-scaled score system. Conclusion: The overall incidence of echocardiographic paravalvular leak gr aded more than trivial or mild was low (1.6%) in patients followed for a me an of 1.1 +/- 0.5 years (range: 1-27 months) after valve replacement with S ilzone-coated heart valve prostheses. No patient required reoperation due t o paravalvular leak, moreover, the stroke rate (1.5%/year) was low in these patients. The present data indicated no significant disadvantages or highe r rate of complications related to silver coating compared with other, non- silver-coated prostheses. Future investigation is needed to determine long- term outcome.