Silzone coating and paravalvular leak: an independent, randomized study.
OBJECTIVE
The study aim was to address independently, in a randomized patient cohort, the impact of Silzone coating on the prevalence and impact of paravalvular leak in patients undergoing mechanical valve replacement.


METHODS
Randomized implantation of the uncoated St. Jude Medical Masters, and the Silzone-coated prosthesis was performed in 95 patients, excluding those with suspected or diagnosed infective endocarditis. The company did not support the study; this cohort is not contained in the AVERT trial. Following recall of the Silzone-coated valves, all patients in this cohort were invited to undergo control transthoracic echocardiography and plasma LDH determination.


RESULTS
Silzone-coated valves were implanted in 46 patients (57 valves; 34 aortic, 20 mitral, three tricuspid), and uncoated valves in 49 patients (55 valves; 38 aortic, 16 mitral, one tricuspid). One patient with an uncoated mitral valve died from left ventricular dissection. In total, 73 patients returned for specifically planned echocardiography (mean interval 478+/-78 days). Sixteen patients underwent echocardiography on another occasion (mean interval 113+/-202 days). Six hospital survivors did not undergo any postoperative echocardiography. In total, 51 Silzone-coated valves (31 aortic, 18 mitral, two tricuspid), and 53 uncoated valves (37 aortic, 15 mitral, one tricuspid) were evaluated. No patients were reoperated for intrinsic or extrinsic valve dysfunction. No major paravalvular leaks were seen. Five of 51 Silzone-coated valves showed minimal (grade <1+; four aortic, one mitral) paravalvular leak when specifically sought; two showed minimal (grade <1+; one aortic, one mitral), and one slight (grade 1+; one mitral) paravalvular leak in the uncoated group (p = 0.55). The LDH level was 654+/-163 U/I in the Silzone group, and 598+/-124 U/l in the control group (p = 0.10).


CONCLUSIONS
No differences were detected in the incidence of paravalvular leak between Silzone-coated and uncoated mechanical St. Jude Medical valves. The incidence of major paravalvular leaks appears to be lower in the present cohort than was reported in the AVERT trial.
Herijgers
P
P
Department of Cardiac Surgery, UZ Gasthuisberg, Katholieke Universiteit Leuven, Belgium.
Herregods
M C
MC
Vandeplas
A
A
Meyns
B
B
Flameng
W
W
D000368:Aged; D015331:Cohort Studies; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D006349:Heart Valve Diseases / Q000097:blood / Q000000981:diagnostic imaging / Q000601:surgery*; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011475:Prosthesis Failure; D012834:Silver; D013997:Time Factors
D012834:Silver; D007770:L-Lactate Dehydrogenase