A novel method of evaluating the critical Fontan candidates with markedly developed V-V shunts by balloon occlusion of the IVC

  • Dr Shoji Suzuki, Department of Surgery, University of Yamanashi, Japan
  • Dr Shigeaki Kaga, Department of Surgery, University of Yamanashi, Japan
  • Dr Minako Hoshiai, Department of Pediatrics, University of Yamanashi, Japan
  • Dr Toshie Kadono, Department of Pediatrics, University of Yamanashi, Japan
  • Dr Kohsuke Kise, Department of Pediatrics, University of Yamanashi, Japan
  • Dr Yoshihiro Honda, Department of Surgery, University of Yamanashi, Japan
  • Dr Kisho Shimura, Department of Surgery, University of Yamanashi, Japan
  • Prof Masahiko Matsumoto, Department of Surgery, University of Yamanashi, Japan

    • Background: The markedly developed V-V shunts via venous plexus after bidirectional Glenn operation (BDG) is a hurdle in preoperative assessment for a definitive Fontan operation, because it leads to underestimation of the pulmonary arterial pressure (PAP) due to the stealing flow. Moreover, it may occasionally cause a progressive desaturation which can not be treated by coil embolization. Method: Two HLHS patients, 32 and 34 months old, weighing 11.5 and 10.2 kg respectively, were evaluated. They had undergone staged Norwood operations, and developed critical desaturation after BDG due to huge V-V shunts between the upper and the lower body, probably related to the small central PA behind the reconstructed neo-aorta. The IVC was occluded by a 15 mm balloon, and hemodynamics was observed for more than 5 minutes. Subsequently, an IVC venography was done. Results: The arterial saturation significantly jumped up, by 6-12 %. The IVC pressure had increased by 4-5 mmHg, whereas the systemic blood pressure remained unchanged. Interestingly, the mean PAP declined by 2-3 mmHg during the occlusion. The venography showed a reversed upstream of the shunt flow. We performed fenestrated TCPC based on these data, and got satisfactory results. Comments and Conclusions: A decrease in the PAP suggests the effect of the declined atrial pressure or the presence of an unknown PA flow-mediated reaction. The IVC occlusion test should be contemplated to assess the possibility of Fontan circulation in critical candidates.