Evaluation of p53 Polymorphism in Patients with Pannus-Derived Prosthetic Dysfunction

BACKGROUND AND AIM OF THE STUDY: Prosthetic valve dysfunction (PVD) due to pannus formation is considered to occur due to a bioreaction to prosthetic material. The p53 gene plays a critical role in apoptosis and cell proliferation. p53 Arg72Pro polymorphism has been found to be associated with coronary stent restenosis, but has not yet been studied in prosthetic heart valve dysfunction. The study aim was to evaluate the association between pannus-derived PVD and p53 G72C(Arg72Pro) polymorphism.

METHODS: This single-center, prospective study included 25 patients (20 females, five males; mean age 45.6 +/- 12.5 years; group 1) who underwent redo valve surgery due to PVD, and 49 age- and gender-matched control patients (44 females, five males; mean age 47.3 +/- 12.2 years; group 2) with normofunctional prostheses. The prostheses were examined using transthoracic and transesophageal echocardiography. Analyses of p53 G72C(Arg72Pro) polymorphism were performed using Roche LightCyler 2.0 Real-time polymerase chain reaction.

RESULTS: The most common location of replaced valves was the mitral position in both groups (88% and 89.8%, respectively). In group 1, normal alleles (GG) were observed in 12 patients (48%), while one patient (4%) showed a homozygous mutation (GC) and 12 patients (48%) showed a heterozygous mutation (CC). In group 2, 21 patients (42.9%) had normal alleles (GG), while four (8.2%) had a homozygous mutation (CC) and 24 (48.9%) had a heterozygous mutation (GC). No significant difference was observed between the groups with regards to p53 Arg72Pro polymorphism (p = 0.769).

CONCLUSION: In patients with prosthetic valves, the underlying mechanism behind pannus formation is unrelated to p53 Arg72Pro polymorphism.