A follow-up study with radionuclide imaging and angiocardiography for pulmonary perfusion after Fontan operation / 中华核医学与分子影像杂志

ABSTRACT

Objective To study the long-term effect of total right heart bypass on pulmonary perfusion after extracardiac total cavopulmonary connection (ETCPC).Methods Fifty-three patients (29males,24 females; average age (10.8±6.1) years) undergoing ETCPC from March 1990 to December 2005were retrospectively analyzed.Forty-three patients had full set of pulmonary perfusion data at 1 month and 5years postoperation.The perfusion ratios of each lung segment were calculated based on 99Tcm-MAA radionuclide imaging.The PVR and pulmonary artery index were calculated from angiocardiography measurements.All data were compared with paired t test.Results Compared with the early postoperative data,the perfusion ratio of superior/inferior segment(0.72±0.20 vs 0.75±0.01; t =2.54,P＜0.05),the PVR ((142.98±2.61) vs (146.95±2.54) dyn · s · cm-5; t=2.08,P＜0.05; 1 dyn · s · cm-5 =0.1 kPa · s · L-1) and vena cava pressure ((9.35±0.24) vs (9.95±0.23) mmHg; t=2.69,P＜0.05; 1 mmHg=0.133 kPa) decreased significantly in follow-up data; while the ratio of posterior basal segment perfusion increased significantly (0.12±0.00 vs 0.10±0.03; t=2.16,P＜0.05).The arterial oxygen saturation ((92.70±0.30)％ vs (92.86±0.29) ％ ; t =1.12,P＞0.05),the total pulmonary nuclear counts ((701.91 ± 8.26) × 103 vs (698.93 ± 12.0) ×103 ; t=0.38,P＞0.05) and the perfusion ratio of inferior vena cava to the right lung (0.61±0.06 vs 0.60±0.06 ; t =0.74,P ＞ 0.05) were similar between the two terms of follow-up.The early angiographic and radionuclide perfusion studies did not match in 5 patients.Conclusions Hypostatic redistribution of pulmonary blood flow is the characteristics in long-term follow-up of ETCPC patients.The radionuclide imaging is superior to angiocardiography in revealing functional pulmonary blood perfusion.