ABSTRACT
ObjectiveTo study the pulmonary arterial development over five years in patients underwent extracardiac total cavopulmonary connection (ETCPC).Methods43 survived patients,who had undergone ETCPC were examined with pulmonary perfusion at one month and five year following the operation.Central venous pressure (CVP) and arterial oxygenation saturation (SatO2 ％ ) were measured by right cardiac catheter,pulmonary arterial index (PAI) and pulmonary vascular resistance (PVR) were calculated.Pulmonary blood distribution were measured and calculated by 99m Tc-MAA perfusion imaging.ResultsThe PAI and PVR of the follow-up group reduced significantly ( t =2.41,P ＜ 0.05 ; t =2.08,P ＜ 0.05 ),CVP also reduced significantly ( t =2.69,P ＜ 0.05 ),but SatO2 ％ did not changed significantly.Total radionuclide counts and the ratio of rightorleft pulmonary perfusion did not change significantly.( t =0.38,P ＞ 0.05 ;t =1.12,P ＞ 0.05 ),but the ratio of the superior and inferior lobe decreased significantly( t =2.54,P ＜ 0.05 ).ConclusionThe weak pulsation and low dynamic of Fontan circulation also can promote pulmonary vascular development.However,the improvement of hemodynamic in pulmonary circulation at mid-term follow will not lead to an increased amount of pulmonary perfusion or oxygen supply,which is probably due to the massive opening of the arteriovenous shunt and increased futile circulation.
ABSTRACT
PURPOSE: Determination of pulmonary to systemic blood flow ratio (QP/QS) is important for the management of patients with left-to-right shunt. This study was performed to assess the agreement of Qp/Qs ratio using the radionuclide method and oxymetry, to investigate the factors influencing the agreement, and to know how interchangeable the results of each technique. MATERIALS AND METHODS: We compared the Qp/Qs measured by single-pass radionuclide angiocardiography and oxymetry during catheterization in 207 patients who underwent both studies. In radionuclide method, Qp/Qs was calculated from the pulmonary time-activity curves using a gamma variate fit. The correlation and Bland-Altman analysis were performed according to the levels of shunt and associated lesions. RESULTS: The mean Qp/Qs was 1.83+/10.50 by radionuclide, and 1.74+/10.51 by oxymetry. The overall correlation coefficient was 0.86(p<0.001), and Bland-Altman range of agreement encompassing 4SD was 1.05. For atrial septal defect, ventricular septal defect, patent ductus arteriosus, tricuspid and mitral insufficiency, the correlation coefficient was 0.78, 0.90, 0.84, 0.63 and 0.44, and Bland-Altman range was 1.52, 0.74, 0.96, 1.57, and 1.50, respectively. CONCLUSION: There is good agreement but wide variance between the Qp/Qs ratios by radionuclide method and oxymetry. Associated atrioventricular valvar insufficiency decreases the correlation coefficient and widens the variance. Wide overall variance suggests that Qp/Qs measurements by two techniques should not be used interchangeably.