BACKGROUND Patients requiring congenital and structural heart interventions often require large-sized sheath insertion into femoral veins and arteries. Clinical outcome data on the use of suture-mediated devices for femoral venous access site closure are limited. OBJECTIVE To assess the efficacy and safety of the Perclose™ (Abbott Vascular Devices, CA) suture-mediated device using the preclosure technique, in achieving haemostasis at femoral venous access site following large sheath insertion (≥8 Fr). DESIGN AND SETTING Two hundred and forty-three consecutive patients underwent 310 access site closures with the Perclose™ device using the preclosure technique. There were 151 (62%) women, mean age 43 (±16) years. 234/243 (96%) received heparin. Mean venous access site sheath diameter was 11.5 (±3) Fr. RESULTS Immediate haemostasis (<2 min) was achieved in 304/310 (98%) sites. No patients had major complications. Short-term follow-up at 3 months revealed no evidence of haematoma or fistula formation or clinical evidence of vessel occlusion. On medium-term clinical follow-up (mean follow-up of 14 ± 12 and median of 12.4 months), no complications were seen at the venous access sites. CONCLUSION Preclosure of large-size femoral venous access sheath sites using the suture-mediated Perclose™ device is efficacious in achieving rapid haemostasis in the presence of anticoagulation in the venous site. On 1-year follow-up, there was no clinical evidence of vascular complications in the venous access sites.