Introduction Surgical repair employing a valved homograft con- duit between the right ventricle (RV) and pulmonary artery (PA) is now considered to be a standard procedure for many complex congenital cardiac anomalies with right ventricular outflow tract obstruction (RVOTO) and/or pulmonary insuffi- ciency. Despite progress in methods for preservation of valved conduits, the progressive degeneration of Tsvetomir Loukanov Christian Sebening Wolfgang Springer Markus Khalil Herbert E. Ulmer Siegfried Hagl Matthias Karck Matthias Gorenflo Replacement of valved right ventricular to pulmonary artery conduits: an observational study with focus on right ventricular geometry Received: 24 May 2007 Accepted: 10 September 2007 Published online: 28 November 2007 j Abstract Objective Timing of the operation for exchange of right ventricular (RV) to pulmonary artery (PA) conduits is a matter of considerable debate. We aimed to study the course of right ventricular dimension in patients undergoing conduit exchange. Patients and methods We retrospectively studied all patients who underwent implantation and or replacement of RV/PA conduits during the time period between 1990 and 2005. Clinical and echocardiographic data were recorded as obtained at follow-up visits. Results A total of 229 (144 boys and 85 girls) underwent surgery for implantation and or replacement of RV/PA conduits during the study period. Patients were assigned to three age groups including 37 infants, 125 children aged 1)10 years and 67 patients more than 10 years of age. 185 pulmonary (81%) and 44 aortic homografts (19%) were implanted. Fifty-eight of these 185 patients (25%) required exchange of conduits after a median time of 6.4 (8 months– 12 years) (median (range)). The follow-up was 7.55 (0.1–17) years. The survival of the patients after homograft change was 98%. Freedom from failure for aortic and pulmonary homografts at an interval of 10 years for all patients was 38.5% for aortic and 56.2% for pulmonary homografts (P = 0.018; Mann–Whitney). Age at conduit exchange (coefficient: )4.917; P < 0.001) and right ventricular end-diastolic dimension (RVDD) before conduit exchange (coefficient: 8.255; P < 0.001) were related to RVDD as measured by M-mode echocardiography at follow-up (‘‘best subset’’ regression analysis; R squared = 0.746). RVDD decreased in 48/ 58 patients, remained unchanged in 8/58 and increased in 2/59 patients at follow-up. An increased RVDD was positively correlated to the duration of artificial ventilation after the operation for conduit exchange (R = 0.56; P < 0.001). Conclusions Reoperation for exchange of degen- erated conduits should be performed early to prevent the development of irreversible structural myocardial changes and persistence of right ventricular dilatation. j Key words homografts – reoperation – right ventricle – dysfunction ORIGINAL PAPER Clin Res Cardiol 97:169–175 (2008) DOI 10.1007/s00392-007-0599-4 CRC 599 T. Loukanov, MD (&) C. Sebening S. Hagl M. Karck Department of Cardiothoracic Surgery University Medical Centre Im Neuenheimer Feld 110 69120 Heidelberg, Germany Tel.: +49-6221/56-6272 Fax: +49-6221/56-5585 E-Mail: tsvetomir.loukanov@med.uni- heidelberg.de W. Springer M. Khalil H.E. Ulmer M. Gorenflo Department of Pediatric Cardiology and Congenital Heart Disease University Medical Centre Im Neuenheimer Feld 110 69120 Heidelberg, Germany