Polytetrafluoroethylene graft calcification in patients with surgically repaired congenital heart disease: Evaluation using multidetector-row computed tomography

Background Noninvasive determination of calcified prosthetic polytetrafluoroethylene (PTFE) is important in improving risk stratification. The purpose of this study is to assess the feasibility of multidetector-row computed tomography (MDCT) for the evaluation of PTFE calcification in patients with surgically repaired congenital heart disease and to evaluate the development and characteristics of calcification for specific surgical procedures. Methods Seventy-six implanted PTFE grafts in 47 patients were evaluated by MDCT (Aquillion 16, Toshiba Corporation, Tokyo, Japan). Explanted PTFE grafts were evaluated histologically in 4 patients who underwent reoperation after MDCT scans. Results Calcification of prosthetic PTFE was detected in 5 of 29 cases (17%) for ventricular septal defect (VSD) patches, 26 of 32 (81%) for right ventricular outflow tract (RVOT) prosthesis, 2 of 8 (25%) for atrial septal patches of the Fontan procedure, and 7 of 7 (100%) for extracardiac conduits of total cavopulmonary connection. The CT attenuation of PTFE revealed significantly different values for VSD patches (114 +/- 61 Hounsfield units [HU]), RVOT prosthesis (243 +/- 132 HU), atrial septal patches (163 +/- 161 HU), and extracardiac conduits (230 +/- 29 HU) (P < .0001). The CT density value of VSD patches was significantly lower than those of RVOT grafts and extrocardiac conduits (P < .05). The MDCT findings were consistent with histologic analysis in the evaluation of calcification. Conclusions This study demonstrates that MDCT enables the evaluation of prosthetic PTFE graft calcification; PTFE grafts in 4 different implantation sites demonstrated distinctive features and the prevalence of calcification.